24652 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

1The definition of ‘‘frame or receiver’’ in section 

479.11 differs slightly from the definition in section 

478.11 in that it omits an Oxford comma between 

‘‘bolt or breechblock’’ and ‘‘firing mechanism.’’ 

DEPARTMENT OF JUSTICE 

Bureau of Alcohol, Tobacco, Firearms, 

and Explosives 

27 CFR Parts 447, 478, and 479 

[Docket No. 2021R–05F; AG Order No. 

5374–2022] 

RIN 1140–AA54 

Definition of ‘‘Frame or Receiver’’ and 

Identification of Firearms 

AGENCY: Bureau of Alcohol, Tobacco, 

Firearms, and Explosives; Department of 

Justice. 

ACTION: Final rule. 

SUMMARY: The Department of Justice 

(‘‘Department’’) is amending Bureau of 

Alcohol, Tobacco, Firearms, and 

Explosives (‘‘ATF’’) regulations to 

remove and replace the regulatory 

definitions of ‘‘firearm frame or 

receiver’’ and ‘‘frame or receiver’’ 

because the current regulations fail to 

capture the full meaning of those terms. 

The Department is also amending ATF’s 

definitions of ‘‘firearm’’ and ‘‘gunsmith’’ 

to clarify the meaning of those terms, 

and to provide definitions of terms such 

as ‘‘complete weapon,’’ ‘‘complete 

muffler or silencer device,’’ ‘‘multipiece frame or receiver,’’ ‘‘privately 

made firearm,’’ and ‘‘readily’’ for 

purposes of clarity given advancements 

in firearms technology. Further, the 

Department is amending ATF’s 

regulations on marking and 

recordkeeping that are necessary to 

implement these new or amended 

definitions. 

DATES: This rule is effective August 24, 

2022. 

FOR FURTHER INFORMATION CONTACT: 

Vivian Chu, Office of Regulatory Affairs, 

Enforcement Programs and Services, 

Bureau of Alcohol, Tobacco, Firearms, 

and Explosives, U.S. Department of 

Justice, 99 New York Ave. NE, 

Washington, DC 20226; telephone: (202) 

648–7070. 

SUPPLEMENTARY INFORMATION: 

I. Executive Summary 

A. Summary of the Regulatory Action 

B. Summary of Costs and Benefits 

II. Background 

A. ATF’s Application of the Definitions to 

Split Frames and Receivers 

B. Privately Made Firearms 

C. Advanced Notice of Proposed 

Rulemaking on Identification Markings 

Placed on Firearm Silencers and Firearm 

Mufflers 

III. Notice of Proposed Rulemaking 

A. Definition of ‘‘Firearm’’ 

B. Definition of ‘‘Frame or Receiver’’ 

C. Definition of ‘‘Readily’’ 

D. Definitions of ‘‘Complete Weapon’’ and 

‘‘Complete Muffler or Silencer Device’’ 

E. Definition of ‘‘Privately Made Firearm’’ 

F. Definition of ‘‘Importer’s or 

Manufacturer’s Serial Number’’ 

G. Definition of ‘‘Gunsmith’’ 

H. Marking Requirements for Firearms 

I. Recordkeeping 

J. Record Retention 

IV. Analysis of Comments and Department 

Responses for the Proposed Rule 

A. Issues Raised in Support of the Rule 

B. Issues Raised in Opposition to the Rule 

V. Final Rule 

A. Definition of ‘‘Firearm’’ 

B. Definition of ‘‘Frame or Receiver’’ 

C. Definition of ‘‘Readily’’ 

D. Definitions of ‘‘Complete Weapon’’ and 

‘‘Complete Muffler or Silencer Device’’ 

E. Definition of ‘‘Privately Made Firearm’’ 

F. Definition of ‘‘Importer’s or 

Manufacturer’s Serial Number’’ 

G. Definition of ‘‘Gunsmith’’ 

H. Marking Requirements for Firearms 

I. Recordkeeping 

J. Record Retention 

K. Effect on Prior ATF Rulings and 

Procedures 

L. Severability 

VI. Statutory and Executive Order Review 

A. Executive Orders 12866 and 13563 

B. Executive Order 13132 

C. Executive Order 12988 

D. Regulatory Flexibility Act 

E. Small Business Regulatory Enforcement 

Fairness Act of 1996 

F. Congressional Review Act 

G. Unfunded Mandates Reform Act of 1995 

H. Paperwork Reduction Act of 1995 

I. Executive Summary 

A. Summary of the Regulatory Action 

There are no statutory definitions for 

the terms ‘‘frame’’ or ‘‘receiver’’ in the 

Gun Control Act of 1968 (‘‘GCA’’) or the 

National Firearms Act of 1934 (‘‘NFA’’). 

To implement these statutes, the terms 

‘‘firearm frame or receiver’’ and ‘‘frame 

or receiver’’ were defined in regulations 

to mean ‘‘[t]hat part of a firearm which 

provides housing for the hammer, bolt 

or breechblock, and firing mechanism, 

and which is usually threaded at its 

forward portion to receive the barrel.’’ 

27 CFR 478.11 (implementing GCA, 

Title I); 27 CFR 479.11 1 (implementing 

GCA, Title II). These definitions were 

meant to provide direction as to which 

portion of a weapon is the frame or 

receiver for purposes of licensing, 

serialization, and recordkeeping, 

thereby ensuring that a component 

necessary for the functioning of the 

weapon could be traced if later involved 

in a crime. 

However, a restrictive application of 

these definitions would not describe the 

frame or receiver of most firearms 

currently in circulation in the United 

States. Most modern weapon designs, 

including semiautomatic rifles and 

pistols with detachable magazines, have 

a split or multi-piece receiver where the 

relevant fire control components are 

housed by more than one part of the 

weapon (e.g., the upper receiver and 

lower receiver of an AR–15 rifle), or 

incorporate a striker to fire the weapon, 

rather than a hammer. 

In the past few years, some courts 

have treated the regulatory definition of 

‘‘firearm frame or receiver’’ as inflexible 

when applied to the lower portion of the 

AR–15-type rifle, one of the most 

popular firearms in the United States. If 

broadly followed, that result could 

mean that as many as 90 percent of all 

firearms (i.e., with split frames or 

receivers, or striker-fired) in the United 

States would not have any frame or 

receiver subject to regulation. 

Furthermore, technological advances 

have also made it easier for companies 

to sell firearm parts kits, standalone 

frame or receiver parts, and easy-tocomplete frames or receivers to 

unlicensed persons, without 

maintaining any records or conducting 

a background check. These parts kits, 

standalone frame or receiver parts, or 

partially complete frames or receivers 

enable individuals to make firearms 

quickly and easily. Such privately made 

firearms (‘‘PMFs’’), when made for 

personal use, are not required by the 

GCA to have a serial number placed on 

the frame or receiver, making it difficult 

for law enforcement to determine 

where, by whom, or when they were 

manufactured, and to whom they were 

sold or otherwise transferred. Because of 

the difficulty with tracing illegally sold 

or distributed PMFs, those firearms are 

also commonly referred to as ‘‘ghost 

guns.’’ 

For these many reasons, ATF is 

promulgating a rule that would bring 

clarity to the definition of ‘‘frame or 

receiver’’ by providing an updated, 

more comprehensive definition. On May 

21, 2021, the Department published a 

Notice of Proposed Rulemaking 

(‘‘NPRM’’) in the Federal Register, 86 

FR 27720, proposing to redefine the 

term ‘‘frame or receiver’’ as that which 

provides housing or a structure to hold 

or integrate one or more fire control 

components. In light of the comments 

received, this final rule revises the 

proposed definition of ‘‘frame or 

receiver’’ so that a ‘‘frame’’ is applicable 

to a handgun, and variants thereof, and 

a ‘‘receiver’’ is applicable to a rifle, 

shotgun, or projectile weapon other than 

a handgun, and variants thereof. 

Moreover, ‘‘frame or receiver’’ will be 

defined to describe only a single part 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24653 

2ATF occasionally issues serial numbers for 

placement on firearms in which the serial numbers 

were not originally placed, see 26 U.S.C. 5842(b), 

or were accidentally removed, damaged, or worn 

due to routine use or other innocent reason. 

that provides housing or a structure for 

one specific, primary fire control 

component of weapons that expel a 

projectile, or one specific, primary 

internal sound reduction component of 

firearm mufflers or silencers. The final 

rule also defines the meaning of 

‘‘variants’’ and ‘‘variants thereof.’’ The 

final rule provides detailed examples 

along with pictures identifying the 

frame or receiver of a variety of common 

models under the updated definition. 

The final rule also exempts from the 

new definitions and marking 

requirements existing split frame or 

receiver designs in which a part was 

previously classified by ATF as the 

firearm ‘‘frame or receiver’’ and 

provides examples and pictures of select 

exempted frames or receivers, such as 

AR–15/M–16 variant firearms. The only 

exception to ‘‘grandfathering’’ will be 

for partially complete, disassembled, or 

nonfunctional frames or receivers, 

including weapon or frame or receiver 

parts kits, that ATF did not classify as 

firearm ‘‘frames or receivers’’ as defined 

prior to this rule. 

The final rule also specifies, with 

more clarity and examples than the 

NPRM, how these terms apply to multipiece frames or receivers (i.e., those that 

may be disassembled into multiple 

modular subparts), to firearm mufflers 

and silencers, to partially complete, 

disassembled, or nonfunctional frames 

or receivers, including frame or receiver 

parts kits, and to frames or receivers that 

are destroyed. The final rule also 

provides detailed examples of when 

such items are considered readily 

completed, assembled, restored, or 

otherwise ‘‘converted’’ to function as a 

frame or receiver. At the same time, the 

final rule makes clear that articles that 

have not yet reached a stage of 

manufacture where they are clearly 

identifiable as an unfinished component 

of a frame or receiver (e.g., unformed 

blocks of metal, liquid polymers, or 

other raw materials) are not frames or 

receivers. 

Consistent with the GCA, and to 

ensure proper licensing, marking, 

recordkeeping, and background checks 

with respect to certain weapon parts 

kits, the final rule adopts the proposed 

clarification of the term ‘‘firearm’’ to 

include weapon (e.g., pistol, revolver, 

rifle, or shotgun) parts kits that are 

designed to or may readily be 

completed, assembled, restored, or 

otherwise converted to expel a projectile 

by the action of an explosive. This rule 

also finalizes, with minor changes, the 

proposed definition of ‘‘privately made 

firearm.’’ It amends the regulations to 

require that all firearms privately 

manufactured or ‘‘made’’ by 

nonlicensees without identifying 

markings that are taken into inventory 

by licensees be identified (or marked) 

and recorded so that they may be traced 

by law enforcement through their 

records if they are later involved in 

crime. As with the NPRM, the final rule 

does not mandate unlicensed persons to 

mark their own PMFs for personal use, 

or when they occasionally acquire them 

for a personal collection or sell or 

transfer them from a personal collection 

to unlicensed in-State residents 

consistent with Federal, State, and local 

law. 

In addition, the rule finalizes the 

proposed amendments to the term 

‘‘gunsmith’’ to include persons who 

engage in the business of identifying 

firearms for nonlicensees, thus ensuring 

greater access to professional marking 

services for PMFs. The final rule 

clarifies the gunsmithing rules proposed 

in the NPRM by stating the following: 

(1) Licensed firearms dealers (in 

addition to licensed manufacturers and 

importers) may conduct same-day 

adjustments or repairs of all firearms, 

including PMFs, without taking them 

into inventory, provided they are 

returned to the person from whom they 

were received; (2) nonlicensees may 

mark PMFs for a licensee under the 

licensee’s direct supervision; and (3) 

licensees may adopt an existing unique 

identification number previously placed 

on a PMF by a nonlicensee under 

certain conditions. 

In response to comments, the final 

rule permits licensed manufacturers to 

adopt the serial number and other 

identifying markings previously placed 

on a firearm without a variance from 

ATF, provided the firearm has not been 

sold, shipped, or otherwise disposed of 

to a person who is not a licensed 

manufacturer, superseding ATF Ruling 

2009–5. The rule permits licensed 

manufacturers to perform gunsmithing 

services on existing, marked firearms 

without marking or obtaining a marking 

variance, superseding ATF Ruling 

2010–10. It also finalizes, with some 

modifications, the proposed definition 

of the term ‘‘importer’s or 

manufacturer’s serial number’’ to help 

ensure that the serial number and 

associated identifying markings 

required to be placed on a firearm, 

including those placed on a PMF or an 

ATF-issued serial number,2 are 

considered the ‘‘importer’s or 

manufacturer’s serial number’’ protected 

by 18 U.S.C. 922(k), which prohibits 

possession or receipt of a firearm that 

has had the importer’s or manufacturer’s 

serial number removed, obliterated, or 

altered. 

The final rule adopts, with minor 

clarifying changes, the proposed 

clarifications to the marking and 

recordkeeping requirements for 

licensees. First, the rule finalizes the 

definitions for ‘‘complete weapon’’ and 

‘‘complete muffler or silencer device,’’ 

and adds a new definition for ‘‘multipiece frame or receiver’’ under the new 

definition of ‘‘frame or receiver.’’ The 

rule also specifies a reasonable time 

period in which a complete weapon or 

a complete muffler or silencer device, or 

the frame or receiver of a weapon or 

device (including a modular subpart of 

a multi-piece frame or receiver), must be 

marked with a serial number and other 

identifying information and recorded. 

Second, the rule finalizes the proposed 

updates to the information required to 

be marked on the frame or receiver, 

clarifies the meaning of the marking 

terms ‘‘identify,’’ ‘‘legibly,’’ and 

‘‘conspicuously,’’ and authorizes 

firearms licensees to adopt identifying 

markings in the manufacturing process. 

Third, the rule finalizes the proposal to 

require all licensees to consolidate their 

records of manufacture, acquisition, and 

disposition of firearms, and to eliminate 

duplicate recordkeeping entries. Fourth, 

with respect to parts defined as firearm 

mufflers or silencers, which are difficult 

to mark and record, this rule finalizes 

with minor clarifying changes the 

proposed amendments that allow for 

them to be transferred between licensees 

qualified under the NFA for purposes of 

further manufacture or repair of 

complete devices without immediately 

marking and registering them in the 

National Firearms Registration and 

Transfer Record (‘‘NFRTR’’). Fifth, the 

rule finalizes with minor clarifying 

changes the proposed amendments that 

set forth the process by which persons 

may voluntarily seek a determination 

from ATF on whether an item or kit 

they wish to manufacture or possess is 

a firearm or armor piercing ammunition 

subject to marking, recordkeeping, and 

other applicable Federal laws and 

regulations. These amendments to the 

regulations will help ensure that 

firearms can be traced efficiently and 

effectively by law enforcement through 

the records of licensees, and help 

prevent the acquisition of easy-tocomplete firearms by prohibited persons 

and terrorists. 

Lastly, the rule finalizes with minor 

changes the proposed requirement that 

all licensees retain their records until 

the business or licensed activity is 

discontinued, either on paper or in an 


jspears on DSK121TN23PROD with RULES2
24654 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

3NFA provisions still refer to the ‘‘Secretary of 

the Treasury.’’ See generally 26 U.S.C. ch. 53. 

However, the Homeland Security Act of 2002, 

Public Law 107–296, 116 Stat. 2135, transferred the 

functions of ATF from the Department of the 

Treasury to the Department of Justice, under the 

general authority of the Attorney General. 26 U.S.C. 

7801(a)(2); 28 U.S.C. 599A(c)(1). Thus, for ease of 

reference, this final rule refers to the Attorney 

General throughout. 

4See also footnote 82, infra, for specific grants of 

rulemaking authority. 

5The Omnibus Crime Control and Safe Streets 

Act of 1968 repealed the FFA and was then 

incorporated into and expanded by the GCA. Public 

Law 90–351, secs. 906–07, 82 Stat. 197, 234–35 

(1968); Public Law 90–618, 82 Stat. 1213 (1968). 

6Additionally, a firearm frame or receiver that is 

not a component part of a complete weapon at the 

time it is sold, shipped, or disposed of must be 

identified in the manner prescribed with a serial 

number and all of the other required markings. 27 

CFR 478.92(a)(2), 479.102(e); ATF Rul. 2012–1. 

7See Webster’s Third New International 

Dictionary 902, 1894 (1971) (a ‘‘frame’’ is ‘‘the basic 

unit of a handgun which serves as a mounting for 

the barrel and operating parts of the arm’’; 

‘‘receiver’’ means ‘‘the metal frame in which the 

action of a firearm is fitted and to which the breech 

end of the barrel is attached’’); John Olson, Olson’s 

Encyclopedia of Small Arms 72 (1985) (the term 

‘‘frame’’ means ‘‘the basic structure and principal 

component of a firearm’’); Steindler’s New Firearms 

Dictionary, p. 209 (1985) (‘‘receiver’’ means ‘‘that 

part of a rifle or shotgun . . . that houses the bolt, 

firing pin, mainspring, trigger group, and magazine 

or ammunition feed system. The barrel is threaded 

into the somewhat enlarged forward part of the 

receiver, called the receiver ring. At the rear of the 

receiver, the butt or stock is fastened. In 

semiautomatic pistols, the frame or housing is 

sometimes referred to as the receiver’’). 

8See 33 FR 18558 (Dec. 14, 1968) (formerly 26 

CFR 178.11). 

9See 36 FR 14257 (Aug. 3, 1971) (formerly 26 

CFR 179.11). 

electronic format approved by the 

Director of ATF (‘‘Director’’), at the 

business or collection premises readily 

accessible for inspection. This includes 

authorization of licensees to store their 

‘‘closed out’’ paper records and forms 

older than 20 years at a separate 

warehouse, which would be considered 

part of the business or collection 

premises for this purpose and subject to 

inspection. These provisions will 

enhance public safety by ensuring that 

acquisition and disposition records of 

all active licensees are not destroyed 

after 20 years and will remain available 

to law enforcement for tracing purposes. 

B. Summary of Costs and Benefits 

The final rule clarifies which firearms 

are subject to regulation under the GCA 

and NFA and associated licensing, 

marking, and recordkeeping 

requirements. The rule requires persons 

who engage in the business of dealing 

in weapon and frame or receiver parts 

kits defined as firearms to be licensed, 

mark the frames or receivers within 

such kits with serial numbers and other 

marks of identification, and maintain 

records of their acquisition and 

disposition. The provisions of these 

statutes and implementing regulations 

are designed to increase public safety 

by, among other things, preventing 

prohibited persons from acquiring 

firearms and allowing law enforcement 

to trace firearms involved in crime. 

To minimize disruption and cost to 

the licensed firearms industry as much 

as possible, and in keeping with the 

public safety goals of the rule, this rule 

grandfathers existing complete frame or 

receiver designs previously determined 

by the Director to be the firearm ‘‘frame 

or receiver’’ of a given weapon. It does 

not grandfather partially complete, 

disassembled, or nonfunctional frames 

or receivers, including weapon or frame 

or receiver parts kits, that ATF did not 

classify as firearm ‘‘frames or receivers’’ 

as previously defined. ATF estimates 

that the 7 percent annualized cost of 

this rule is $14.3 million. 

II. Background 

The Attorney General is responsible 

for enforcing the Gun Control Act of 

1968, as amended, and the National 

Firearms Act of 1934, as amended.3 This 

responsibility includes the authority to 

promulgate regulations necessary to 

enforce the provisions of the GCA and 

NFA. See 18 U.S.C. 926(a); 26 U.S.C. 

7801(a)(2)(A), 7805(a).4 Congress and 

the Attorney General have delegated the 

responsibility for administering and 

enforcing the GCA and NFA to the 

Director of ATF, subject to the direction 

of the Attorney General and the Deputy 

Attorney General. See 26 U.S.C. 

7801(a)(2); 28 U.S.C. 599A(b)(1), (c)(1); 

28 CFR 0.130(a)(1)–(2); T.D. Order No. 

221(2)(a), (d), 37 FR 11696–97 (June 10, 

1972). Accordingly, the Department and 

ATF have promulgated regulations to 

implement the GCA and NFA. See 27 

CFR parts 478, 479. 

On May 21, 2021, the Department 

published in the Federal Register a 

Notice of Proposed Rulemaking 

(‘‘NPRM’’) entitled ‘‘Definition of 

‘Frame or Receiver’ and Identification of 

Firearms,’’ 86 FR 27720, proposing 

changes to various regulations in 27 

CFR parts 447, 478, and 479. The 

comment period for the proposed rule 

concluded on August 19, 2021, and ATF 

received 290,031 comments. 

The NPRM provided a comprehensive 

explanation of the passage of the 

Federal Firearms Act of 1938 (‘‘FFA’’), 

Public Law 75–785, 52 Stat. 1250, its 

repeal, and the subsequent legislative 

history and context leading to 

Congress’s passage of the GCA in 1968, 

as well as the promulgation of the 

definitions for ‘‘frame or receiver’’ that 

ATF and the firearms industry have 

relied on for more than 50 years.5 86 FR 

at 27720–21. The GCA at 18 U.S.C. 

921(a)(3) defines the term ‘‘firearm’’ to 

include not only a weapon that will, is 

designed to, or may readily be converted 

to expel a projectile, but also the 

‘‘frame’’ or ‘‘receiver’’ of any such 

weapon. 18 U.S.C. 921(a)(3)(A), (B). 

Because frames or receivers are 

included in the definition of ‘‘firearm,’’ 

any person who engages in the business 

of manufacturing, importing, or dealing 

in frames or receivers must obtain a 

license from ATF. 18 U.S.C. 

922(a)(1)(A), 923(a). Each licensed 

manufacturer or importer must ‘‘identify 

by means of a serial number engraved or 

cast on the receiver or frame of the 

weapon, in such manner as the Attorney 

General shall by regulations prescribe, 

each firearm imported or manufactured 

by such importer or manufacturer.’’ 6 18 

U.S.C. 923(i); see 27 CFR 478.92, 

479.102. Licensed manufacturers and 

importers must also maintain 

permanent records of production or 

importation, as well as their receipt, 

sale, or other disposition of firearms, 

including frames or receivers. 18 U.S.C. 

923(g)(1)(A); 27 CFR 478.122, 478.123. 

The GCA does not define the terms 

‘‘frame’’ or ‘‘receiver’’ to implement the 

statute, but frames or receivers are the 

primary structural components of a 

firearm to which fire control 

components are attached.7 After the 

GCA was enacted, the terms ‘‘firearm 

frame or receiver’’ and ‘‘frame or 

receiver’’ were defined as ‘‘that part of 

a firearm which provides housing for 

the hammer, bolt or breechblock, and 

firing mechanism, and which is usually 

threaded at its forward portion to 

receive the barrel.’’ 27 CFR 478.11 

(implementing GCA, Title I); 8 27 CFR 

479.11 (implementing GCA, Title II).9

The intent in promulgating these 

definitions was to inform the public and 

industry as to which portion of a firearm 

was the frame or receiver for purposes 

of licensing, serialization, and 

recordkeeping, thus ensuring that a 

necessary component of the weapon 

could be traced if later involved in a 

crime. 

The NPRM discussed that at the time 

the regulatory definitions were 

promulgated, single-framed firearms 

such as revolvers and break-open 

shotguns were far more prevalent for 

civilian (i.e., not military or law 

enforcement) use in the United States 

than split receiver weapons, such as 

semiautomatic rifles and pistols with 

detachable magazines. Single-framed 

firearms incorporate the hammer, bolt or 

breechblock, and firing mechanism 

within the same housing. 86 FR at 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24655 

10United States v. Rowold, 429 F. Supp. 3d 469 

(N.D. Ohio 2019), Testimony of ATF Firearms 

Enforcement Officer Daniel Hoffman at Doc. No. 60, 

Hrg. Tr., Page ID 557 (approximately 10 percent of 

currently manufactured firearms in the United 

States include at least three components in the 

frame or receiver definition), and Defense Expert 

Daniel O’Kelly at Doc. No. 60, Hrg. Tr., Page ID 482 

(‘‘90 some percent of [semiautomatic pistols] do not 

have a part which has more than one of these four 

elements in it and, therefore, don’t qualify, 

according to the definition in the CFR.’’). 

11ATF Internal Revenue Service Memorandum 

#21208 (Mar. 1, 1971) (lower portion of the M–16 

is the frame or receiver because it comes closest to 

meeting the definition of frame or receiver in 26 

CFR 178.11 (now 27 CFR 478.11), and is the 

receiver of a machinegun as defined in the NFA); 

ATF Memorandum #22334 (Jan. 24, 1977) (upper 

half of the FN–FAL rifle is the frame or receiver 

because it was designed to accept the components 

that allow fully automatic fire). The ability to accept 

machinegun parts is considered because both the 

GCA and the NFA regulate machinegun receivers as 

‘‘machineguns.’’ See 18 U.S.C. 921(a)(23); 26 U.S.C. 

5845(b) (‘‘The term [‘‘machinegun’’] shall also 

include the frame or receiver of any such weapon 

[which shoots is designed to shoot, or can be 

readily restored to shoot, automatically more than 

one shot, without manual reloading, by a single 

function of the trigger].’’). 

12Regulations implementing the relevant statutes 

spell the term ‘‘machine gun’’ rather than 

‘‘machinegun.’’ E.g., 27 CFR 478.11, 479.11. For 

convenience, this rule uses ‘‘machinegun,’’ except 

when quoting a source to the contrary. 

13See footnote 11, supra. 

14See footnote 10, supra. 

15The United States military services have 

adopted variants of the Sig Sauer P320 as their 

official sidearm, and are in the process of 

purchasing up to 500,000 of these striker-fired 

pistols. Matthew Cox & Hope Hodge Seck, Army 

Picks Sig Sauer’s P320 Handgun to Replace M9 

Service Pistol, Military.com (Jan. 19, 2017), 

available at https://www.military.com/daily-news/ 

2017/01/19/army-picks-sig-sauer-replace-m9- 

service-pistol.html (last visited Mar. 22, 2022); Jared 

Keller, Every U.S. military branch is about to get its 

hands on the Army’s new sidearm of choice, 

Taskandpurpose.com (Nov. 18, 2020), available at 

https://taskandpurpose.com/military-tech/modularhandgun-system-fielding (last visited Mar. 22, 2022) 

(Sig Sauer delivered its 200,000th P320-variant 

pistol to the military despite the obstacles posed by 

the novel coronavirus). 

16See Jake Bleiberg & Stefanie Dazio, Design of 

AR–15 could derail charges tied to popular rifle, 

APnews.com (Jan. 13, 2020), available at https://

apnews.com/article/ 

396bbedbf4963a28bda99e7793ee6366 (last visited 

Mar. 22, 2022); Dan Morse & Jasmine Hilton, 

Magruder [High School] student bought ‘ghost gun’ 

components online before wounding classmate, 

Wash. Post (Jan. 24, 2022), available at https://

www.washingtonpost.com/dc-md-va/2022/01/24/ 

magruder-shooting-teen-jailed (last visited Mar. 22, 

2022). 

27721. Over time, split receiver firearms 

became popular for civilian use, such as 

the AR–15 semiautomatic rifle (upper 

receiver and lower receiver), Glock 

semiautomatic pistol (upper slide 

assembly and lower grip module), and 

Sig Sauer P320 pistol (M17/18 as 

adopted by the U.S. military) (upper 

slide assembly, chassis, and lower grip 

module). And more firearm 

manufacturers began incorporating a 

striker-fired mechanism, rather than a 

‘‘hammer,’’ in the firing design, such as 

in the Glock pistol. Id. 

A. ATF’s Application of the Definitions 

to Split Frames and Receivers 

The NPRM explained that ATF’s 

regulatory definitions of ‘‘frame or 

receiver’’ do not expressly capture these 

types of firearms (i.e., split frames or 

receivers) that now constitute the 

majority of firearms in the United 

States.10 However, ATF’s position has 

long been that the weapon ‘‘should be 

examined with a view toward 

determining if [either] the upper or 

lower half of the receiver more nearly 

fits the legal definition of ‘receiver,’ ’’ 

and more specifically, for machineguns, 

whether the upper or lower portion has 

the ability to accept machinegun 

parts.11 12 The NPRM listed the variety 

of factors ATF has considered when 

making determinations for firearm 

classifications under the GCA and NFA 

regarding which part of a firearm is the 

frame or receiver, given that neither a 

split nor a multi-piece receiver has a 

portion of its design that falls within the 

precise wording of the existing 

regulatory definition. 86 FR at 27721. 

Indeed, the current definitions were 

never intended, or understood, to be 

exhaustive. The Department discussed 

in the NPRM the existing law and 

congressional intent recognizing that the 

definition of ‘‘frame or receiver’’ need 

not be limited to a strict application of 

the regulation. Id. at 27721–22. At the 

time the current definitions were 

adopted, there were numerous models 

of firearms that did not contain a part 

that fully met the regulatory definition 

of ‘‘frame or receiver,’’ such as the Colt 

1911, FN–FAL, and the AR–15/M–16, 

all of which were originally 

manufactured almost exclusively for 

military use. ATF has long applied the 

factors stated in the NPRM when 

determining which component of those 

weapons qualifies as the frame or 

receiver.13

While ATF for decades has classified 

the lower receiver of the AR–15 rifle as 

a ‘‘frame or receiver,’’ some courts 

recently have treated the regulatory 

definition as inflexible when applied to 

the lower portion of the AR–15-type 

rifle, which is the semiautomatic 

version of the M–16-type machinegun 

originally designed for the U.S. military. 

That was because those courts have read 

the regulatory definition to mean that 

the lower portion of the AR–15 is not a 

‘‘frame or receiver,’’ as it provides 

housing only for the hammer and firing 

mechanism, not the bolt or breechblock. 

See United States v. Rowold, 429 F. 

Supp. 3d 469, 475–76 (N.D. Ohio 2019). 

(‘‘The language of the regulatory 

definition in § 478.11 lends itself to only 

one interpretation: Namely, that under 

the GCA, the receiver of a firearm must 

be a single unit that holds three, not two 

components: (1) The hammer, (2) the 

bolt or breechblock, and (3) the firing 

mechanism.’’); see also United States v. 

Roh, 8:14–cr–00167–JVS, Minute Order 

p. 6 (C.D. Cal. July 27, 2020); United 

States v. Jimenez, 191 F. Supp. 3d 1038, 

1041 (N.D. Cal. 2016). 

The NPRM explained that, if broadly 

followed, these courts’ interpretation of 

ATF’s regulations could mean that as 

many as 90 percent of all firearms now 

in the United States would not have any 

frame or receiver subject to regulation 

under the current definitions.14 Those 

firearms would include numerous 

widely available models, such as Glocktype and Sig Sauer P320 15 pistols, that 

do not utilize a hammer—a named 

component in the existing regulatory 

definition—in the firing sequence. Such 

a narrow interpretation of what 

constitutes a frame or receiver would 

allow persons to avoid obtaining a 

license to engage in the business of 

manufacturing or importing upper or 

lower frames or receivers, which would 

further allow those persons to avoid the 

GCA’s marking, recordkeeping, and 

background check requirements 

pertaining to upper or lower frames or 

receivers. See 86 FR at 27722. In turn, 

prohibited persons may more easily and 

without a background check acquire 

upper and lower receivers that can 

quickly be assembled into 

semiautomatic weapons.16 Moreover, 

law enforcement’s ability to trace 

semiautomatic firearms later used in 

crime would be severely impeded if no 

portion of split or multi-piece frames or 

receivers were subject to any existing 

regulations as described. This result 

would undermine the intent of Congress 

in requiring the frame or receiver of 

every firearm to be identified, see 18 

U.S.C. 923(i), and regulated as a firearm, 

see 18 U.S.C. 921(a)(3)(B). 

B. Privately Made Firearms 

The NPRM explained that 

technological advances have also made 

it easier for companies to sell firearm 

parts kits, standalone frame or receiver 

parts, or partially complete frames or 

receivers to unlicensed persons, posing 

significant challenges to the regulation 

of frames and receivers and enabling 

prohibited individuals to easily make 

firearms at home, especially if aided by 

personally owned equipment or 3D 

printers. These privately made firearms, 

commonly referred to as ‘‘ghost guns,’’ 

are not required by the GCA to have a 


jspears on DSK121TN23PROD with RULES2
24656 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

17 86 FR at 27722 n.17. See also Erik von Ancken, 

Untraceable ‘Ghost Guns’ sold across Central 

Florida, WKMG–TV Orlando (Nov. 15, 2016), 

available at https://www.clickorlando.com/gettingresults/2016/11/15/untraceable-ghost-guns-soldacross-central-florida (last visited Mar. 22, 2022); 

Nicholas J. Simons, Ghost Guns: A Haunting New 

Reality, Rockefeller Institute of Justice (2021), 

available at https://rockinst.org/wp-content/ 

uploads/2021/04/210413-Ghost-Guns-web.pdf (last 

visited Mar. 22, 2022); Travis Taniguchi et al., The 

Proliferation of Ghost Guns: Regulation Gaps and 

Challenges for Law Enforcement, National Police 

Foundation (2021), available at https://

www.policefoundation.org/wp-content/uploads/ 

2021/08/NPF_The-Proliferation-of-Ghost-Guns_

Final_2021.pdf (last visited Mar. 22, 2022); Shanzeh 

Ahmad & Jeremy Gorner, ‘We’re seeing an 

explosion:’ Sheriff Tom Dart, state Sen. Jacqueline 

Collins take aim at ghost guns, propose legislation 

to ban the untraceable weapons, Chi. Trib. (Oct. 14, 

2021), available at https://

www.chicagotribune.com/news/breaking/ct-cookcounty-sheriff-dart-ghost-gun-legislation-20211014- 

whvwjv5aangmtaje27gpllqtvu-story.html (last 

visited Mar. 22, 2022); Brian X. McCrone, ‘3 Pipes 

Turned into a Shotgun’: Nearly 1-in-10 Guns Seized 

in Philly Are Homemade, NBC10 Philadelphia (Oct. 

7, 2021), available at https://

www.nbcphiladelphia.com/news/local/three-metalpipes-turned-into-a-shotgun-nearly-1-in-10-gunsseized-in-philly-are-homemade/2983066 (last 

visited Mar. 22, 2022); Kevin Rector, LAPD declares 

‘ghost guns’ an ‘epidemic,’ citing 400% increase in 

seizures, L.A. Times (Oct. 15, 2021), available at 

https://www.latimes.com/california/story/2021-10- 

15/lapd-says-ghost-guns-an-epidemic-with-seizuresup-400-since-2017 (last visited Mar. 22, 2022); 

Glenn Thrush, ‘Ghost Guns’: Firearm Kits Bought 

Online Fuel Epidemic of Violence, N.Y. Times (Nov. 

14, 2021), available at https://www.nytimes.com/ 

2021/11/14/us/ghost-guns-homemadefirearms.html (last visited Mar. 22. 2022). 

18Source: ATF Office of Strategic Intelligence and 

Information. These numbers (as of January 21, 2022) 

are likely far lower than the actual number of PMFs 

recovered from crime scenes because some law 

enforcement departments incorrectly trace some 

PMFs as commercially manufactured firearms, or 

may not see a need to use their resources to attempt 

to trace firearms with no serial numbers or other 

identifiable markings. The term ‘‘suspected PMF’’ is 

used because of the difficulty of getting law 

enforcement officials to uniformly enter PMF trace 

information into ATF’s electronic tracing system 

(‘‘eTrace’’), resulting in reporting inconsistencies of 

PMFs involved in crime. For example, often PMFs 

resemble commercially manufactured firearms, or 

incorporate parts from commercially manufactured 

firearms bearing that manufacturer’s name, so some 

firearms suspected of being PMFs were entered into 

eTrace using a commercial manufacturer’s name 

rather than as one privately made by individuals. 

The term ‘‘potential crime scenes’’ is used because 

ATF does not know if the firearm being traced by 

the law enforcement agency was found at a crime 

scene as opposed to one recovered by law 

enforcement that had been stolen or otherwise not 

from the scene of a crime. This is because the 

recovery location or correlated crime is not always 

communicated by the agency to ATF in the tracing 

process. 

19The total number of suspected PMFs is greater 

than the 23,906 originally queried and reported as 

of March 4, 2021, in the NPRM, 86 FR at 27722– 

23, due, not only to the addition of CY 2021 data, 

but also to traces being updated with more 

specificity regarding the firearm description since 

that date, and the inclusion of all suspected PMFs 

recovered within this time frame regardless of when 

the trace was entered. 

serial number placed on the frame or 

receiver when made for personal use. 

When PMFs are relinquished by their 

owners, enter commerce, and are later 

recovered and submitted for tracing, the 

absence of markings on PMFs makes it 

extremely difficult for law enforcement 

to determine where, by whom, or when 

they were manufactured, and to whom 

they were sold or otherwise disposed. 

The NPRM discussed the substantial 

increase in the number of PMFs 

recovered from crime scenes throughout 

the country in recent years.17 From 

January 1, 2016, through December 31, 

2021, there were approximately 45,240 

suspected PMFs reported to ATF as 

having been recovered by law 

enforcement from potential crime 

scenes, including 692 homicides or 

attempted homicides (not including 

suicides), and which ATF attempted to 

trace. Broken down by calendar year, 

the total annual numbers of suspected 

PMFs recovered show significant 

proliferation over the past six years: 

2016: 1,758; 2017: 2,552; 2018: 3,960; 

2019: 7,517; 2020: 10,109; 2021: 

19,344.18 19

Numerous criminal cases have been 

brought by the Department to counter 

the illegal trafficking of unserialized 

privately completed and assembled 

weapons, the possession of such 


jspears on DSK121TN23PROD with RULES2ER26AP22.000</GPH>
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24657 

20 86 FR 27723 n.19. See also Dark Web Gun 

Trafficker from Nevada County Pleads Guilty to 

Unlawful Dealing in Firearms, DOJ/OPA (June 22, 

2018), available at https://www.justice.gov/usaoedca/pr/dark-web-gun-trafficker-nevada-countypleads-guilty-unlawful-dealing-firearms; Burlington 

Man Pleads Guilty to Ammunition Charge, DOJ/ 

OPA (Dec. 12, 2018), available at https://

www.justice.gov/usao-ma/pr/burlington-manpleads-guilty-ammunition-charge; Burlington Man 

Sentenced For Ammunition Charge, DOJ/OPA (Mar. 

19, 2019), available at https://www.justice.gov/ 

usao-ma/pr/burlington-man-sentencedammunition-charge; Indiana Residents Indicted on 

Terrorism and Firearms Charges, DOJ/OPA (July 11, 

2019), available at https://www.justice.gov/opa/pr/ 

indiana-residents-indicted-terrorism-and-firearmscharges; Las Vegas Man Charged For Illegally 

Engaging In The Business Of Manufacturing 

Machine Guns Without A License, DOJ/OPA (Sept. 

4, 2019), available at https://www.justice.gov/usaonv/pr/las-vegas-man-charged-illegally-engagingbusiness-manufacturing-machine-guns-without; 

Two Stockton Residents Sentenced for Firearms 

Offenses, DOJ/OPA (Nov. 21, 2019), available at 

https://www.justice.gov/usao-edca/pr/two-stocktonresidents-sentenced-firearms-offenses; Denver Gang 

Member Sentenced To Over 15 Years In Federal 

Prison For Making And Selling Dozens Of High 

Powered Guns, Including Machine Guns And 

Silencers, DOJ/OPA (Nov. 22, 2019), available at 

https://www.justice.gov/usao-co/pr/denver-gangmember-sentenced-over-15-years-federal-prisonmaking-and-selling-dozens-high; Cedar Rapids Man 

Pleads Guilty to Drug Trafficking and Possessing 

Machineguns and a Pipe Bomb, DOJ/OPA (Jan. 21, 

2020), available at https://www.justice.gov/usaondia/pr/cedar-rapids-man-pleads-guilty-drugtrafficking-and-possessing-machineguns-and-pipe; 

Indictment Charges 15 Members of a Los Angeles 

Drug Trafficking Ring that Distributed Heroin, 

Methamphetamine and Cocaine, DOJ/OPA (Feb. 12, 

2020), available at https://www.justice.gov/usaocdca/pr/indictment-charges-15-members-losangeles-drug-trafficking-ring-distributed-heroin; 

Two Queens Men Charged After Buying Three 

Illegally Defaced Firearms and Two Assault Rifles, 

DOJ/OPA (May 13, 2020), available at https://

www.justice.gov/usao-edny/pr/two-queens-mencharged-after-buying-three-illegally-defacedfirearms-and-two-assault; Second Defendant 

Charged with Murder in New Indictment in Case of 

Man Found Dead in Pacific Ocean after Being Shot 

on a Boat, DOJ/OPA (June 25, 2020), available at 

https://www.justice.gov/usao-cdca/pr/seconddefendant-charged-murder-new-indictment-caseman-found-dead-pacific-ocean-after; Fishers 

residents indicted on terrorism and firearms 

charges, DOJ/OPA (July 12, 2019), available at 

https://www.justice.gov/usao-sdin/pr/fishersresidents-indicted-terrorism-and-firearms-charges; 

Outlaws Motorcycle Club Regional President Pleads 

Guilty to Firearms Charges, DOJ/OPA (July 15, 

2020), available at https://www.justice.gov/usaoma/pr/outlaws-motorcycle-club-regional-presidentpleads-guilty-firearms-charges; Sun Valley Man 

Indicted on Federal Narcotics Charges and 

Weapons Offenses, including Possession of Ghost 

Gun and Grenade Launcher, DOJ/OPA (July 23, 

2020), available at https://www.justice.gov/usaocdca/pr/sun-valley-man-indicted-federal-narcoticscharges-and-weapons-offenses-including; Seven 

Defendants Arrested and Charged in Conspiracy to 

Possess and Carry Firearms in Furtherance of Drug 

Trafficking, DOJ/OPA (Sept. 3, 2020), available at 

https://www.justice.gov/usao-dc/pr/sevendefendants-arrested-and-charged-conspiracypossess-and-carry-firearms-furtherance; Takedown 

Completes Arrests of 15 Alleged Drug Traffickers in 

Syracuse Area, DOJ/OPA (Sept. 17, 2020), available 

at https://www.justice.gov/usao-ndny/pr/takedowncompletes-arrests-15-alleged-drug-traffickerssyracuse-area; Three Members of Gardena Street 

Gang Charged in Federal Racketeering Case 

Alleging Murder of Man Outside His Home, DOJ/ 

OPA (Dec. 2, 2020), available at https://

www.justice.gov/usao-cdca/pr/three-membersgardena-street-gang-charged-federal-racketeeringcase-alleging-murder-man; Syracuse Man Pleads 

Guilty to Brokering Illegal Gun Sales, DOJ/OPA 

(Dec. 9, 2020), available at https://www.justice.gov/ 

usao-ndny/pr/syracuse-man-pleads-guiltybrokering-illegal-gun-sales; Gang Member 

Sentenced to More Than 7 Years in Prison for Gun 

and Drug Offenses, DOJ/OPA (Feb. 17, 2021), 

available at https://www.justice.gov/usao-ct/pr/ 

gang-member-sentenced-more-7-years-prison-gunand-drug-offenses; Man Sentenced for Attempting 

to Board International Flight with a Loaded 

Firearm, DOJ/OPA (Mar. 12, 2021), available at 

https://www.justice.gov/usao-sdca/pr/mansentenced-attempting-board-international-flightloaded-firearm; Vacaville Man Sentenced to over 4 

Years in Prison for Unlawfully Possessing 

Ammunition as a Felon, DOJ/OPA (May 4, 2021), 

available at https://www.justice.gov/usao-edca/pr/ 

vacaville-man-sentenced-over-4-years-prisonunlawfully-possessing-ammunition-felon; Big Island 

man arrested on methamphetamine and firearm 

charges, DOJ/OPA (May 18, 2021), available at 

https://www.justice.gov/usao-hi/pr/big-island-manarrested-methamphetamine-and-firearm-charges; 

Fresno Gang Member Faces Federal Firearms 

Charge, DOJ/OPA (June 3, 2021), available at 

https://www.justice.gov/usao-edca/pr/fresno-gangmember-faces-federal-firearms-charge; Temple Hills 

Man Sentenced To Three And A Half Years In 

Federal Prison For Trafficking Of Ghost Guns, DOJ/ 

OPA (June 4, 2021), available at https://

www.justice.gov/usao-md/pr/temple-hills-mansentenced-three-and-half-years-federal-prisontrafficking-ghost-guns; Septuagenarian charged 

with manufacturing ‘‘ghost guns’’, DOJ/OPA (June 

15, 2021), available at https://www.justice.gov/ 

usao-sdtx/pr/septuagenarian-chargedmanufacturing-ghost-guns; Convicted Gun 

Trafficker Pleads Guilty to Firearms Charges, DOJ/ 

OPA (June 22, 2021), available at https://

www.justice.gov/usao-ndny/pr/convicted-guntrafficker-pleads-guilty-firearms-charges; Barnstable 

Man Charged with Firearm Trafficking, DOJ/OPA 

(June 22, 2021), available at https://

www.justice.gov/usao-ma/pr/barnstable-mancharged-firearm-trafficking; Laplace Man Pleads 

Guilty to Being Felon in Possession of Ammunition, 

DOJ/OPA (June 25, 2021), available at https://

www.justice.gov/usao-edla/pr/laplace-man-pleadsguilty-being-felon-possession-ammunition; Felon 

Pleads Guilty to Possession of Ghost Guns and 

Conspiracy to Commit Wire Fraud, DOJ/OPA (June 

28, 2021), available at https://www.justice.gov/ 

usao-md/pr/felon-pleads-guilty-possession-ghostguns-and-conspiracy-commit-wire-fraud; Syracuse 

Man Sentenced to Seven Years in Federal Prison for 

Brokering Illegal Gun Sales, DOJ/OPA (July 8, 

2021), available at https://www.justice.gov/usaondny/pr/syracuse-man-sentenced-seven-yearsfederal-prison-brokering-illegal-gun-sales; Federal 

Drug and Gun Charges Brought Against Fresno Man 

Accused of Dealing Fentanyl, DOJ/OPA (July 15, 

2021), available at https://www.justice.gov/usaoedca/pr/federal-drug-and-gun-charges-broughtagainst-fresno-man-accused-dealing-fentanyl; 

Vineland Boys Gang Member Sentenced to 31 Years 

in Federal Prison for Racketeering Conspiracy, 

Attempted Murder of Rival Gangsters, DOJ/OPA 

(July 22, 2021), available at https://www.justice.gov/ 

usao-cdca/pr/vineland-boys-gang-membersentenced-31-years-federal-prison-racketeeringconspiracy; Hartford Man Charged with Illegally 

Possessing Firearm and Ammunition, DOJ/OPA 

(July 23, 2021), available at https://www.justice.gov/ 

usao-ct/pr/hartford-man-charged-illegallypossessing-firearm-and-ammunition; Philadelphia 

Man Arrested on Murder-For-Hire Charges; 

Attempted Homicide in Southwest Philadelphia 

Thwarted, DOJ/OPA (July 26, 2021), available at 

https://www.justice.gov/usao-edpa/pr/philadelphiaman-arrested-murder-hire-charges-attemptedhomicide-southwest-philadelphia; Rensselaer 

County Felon Sentenced to 30 Months on Firearms 

Convictions, DOJ/OPA (Aug. 10, 2021), available at 

https://www.justice.gov/usao-ndny/pr/rensselaercounty-felon-sentenced-30-months-firearmsconvictions; Three East Bay Men Charged With 

Conspiracy To Traffic Firearms, DOJ/OPA (Aug. 16, 

2021), available at https://www.justice.gov/usaondca/pr/three-east-bay-men-charged-conspiracytraffic-firearms; Raleigh Felon Sentenced After 

Pulling a Firearm on Officers During a Drug 

Investigation, DOJ/OPA (Aug. 17, 2021), available 

at https://www.justice.gov/usao-ednc/pr/raleighfelon-sentenced-after-pulling-firearm-officersduring-drug-investigation; Buffalo Man Arrested, 

Charged With Manufacturing Ghost Guns, DOJ/OPA 

(Aug. 20, 2021), available at https://

www.justice.gov/usao-wdny/pr/buffalo-manarrested-charged-manufacturing-ghost-guns; 

Montgomery County Man Sentenced to 30 Months 

for Unlawfully Selling ‘‘Ghost Guns’’, DOJ/OPA 

(Sept. 2, 2021), available at https://www.justice.gov/ 

usao-ndny/pr/montgomery-county-man-sentenced30-months-unlawfully-selling-ghost-guns; Three 

South Lake Tahoe Residents Charged with Drug 

Trafficking and Texas Man Charged with 

Trafficking Firearms, DOJ/OPA (Aug. 23, 2021), 

available at https://www.justice.gov/usao-edca/pr/ 

three-south-lake-tahoe-residents-charged-drugtrafficking-and-texas-man-charged; New Mexico 

Man Who Sold ‘Ghost Guns’ Indicted, DOJ/OPA 

(Sept. 8, 2021), available at https://www.justice.gov/ 

usao-ndtx/pr/new-mexico-man-who-sold-ghostguns-indicted; Fresno Men Indicted for Being 

Previously Convicted of Violent Crimes in 

Possession of Firearm and Ammunition, DOJ/OPA 

(Sept. 16, 2021), available at https://

www.justice.gov/usao-edca/pr/fresno-men-indictedbeing-previously-convicted-violent-crimespossession-firearm-and; Connecticut Man 

Sentenced for Firearm Trafficking, DOJ/OPA (Sept. 

16, 2021), available at https://www.justice.gov/ 

usao-ma/pr/connecticut-man-sentenced-firearmtrafficking; Two Defendants Indicted For Oahu 

Game Room Robbery, Drug Trafficking, and ‘‘Ghost 

Gun’’ Possession, DOJ/OPA (Sept. 17, 2021), 

available at https://www.justice.gov/usao-hi/pr/twodefendants-indicted-oahu-game-room-robbery-drugtrafficking-and-ghost-gun-possession; D.C. Felon 

Sentenced to 30 Months In Federal Prison For 

Illegal Possession Of A .40 Caliber ‘‘Ghost Gun’’ 

Firearm And 10 Rounds Of Ammunition, DOJ/OPA 

(Sept. 24, 2021), available at https://

www.justice.gov/usao-md/pr/dc-felon-sentenced30-months-federal-prison-illegal-possession-40- 

caliber-ghost-gun; Convicted Felon Sentenced for 

Narcotics Trafficking and Manufacturing ‘‘Ghost 

Guns’’, DOJ/OPA (Sept. 24, 2021), available at 

https://www.justice.gov/usao-edva/pr/convictedfelon-sentenced-narcotics-trafficking-andmanufacturing-ghost-guns; Two District Men 

Indicted on Federal Charges Involving Illegal 

Possession and Sale of Firearms, DOJ/OPA (Sept. 

29, 2021), available at https://www.justice.gov/ 

usao-dc/pr/two-district-men-indicted-federalcharges-involving-illegal-possession-and-salefirearms; Bronx Man Who Possessed Five ‘‘Ghost 

Guns’’ Charged With Possessing A Firearm And 

Ammunition, DOJ/OPA (Oct. 5, 2021), available at 

https://www.justice.gov/usao-sdny/pr/bronx-manwho-possessed-five-ghost-guns-charged-possessingfirearm-and-ammunition; Fresno Felon Indicted for 

Possession of Ammunition, DOJ/OPA (Oct. 7, 2021), 

available at https://www.justice.gov/usao-edca/pr/ 

fresno-felon-indicted-possession-ammunition; 

District Man Sentenced to 101⁄2 Years in Prison for 

Armed Robbery and Earlier Shooting, DOJ/OPA 

(Oct. 13, 2021), available at https://

www.justice.gov/usao-dc/pr/district-mansentenced-10-years-prison-armed-robbery-andContinued 

weapons by prohibited persons, and 

other related Federal crimes.20


jspears on DSK121TN23PROD with RULES2
24658 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

earlier-shooting; Brooklyn Felon Sentenced to 48 

Months’ Imprisonment for Possessing Arsenal of 

Weapons Including ‘‘Ghost Guns’’, DOJ/OPA (Oct. 

12, 2021), available at https://www.justice.gov/ 

usao-edny/pr/brooklyn-felon-sentenced-48-monthsimprisonment-possessing-arsenal-weaponsincluding; Syracuse Man Pleads Guilty to 

Unlawfully Possessing and Selling Firearms and 

Ammunition, DOJ/OPA (Oct. 15, 2021), available at 

https://www.justice.gov/usao-ndny/pr/syracuseman-pleads-guilty-unlawfully-possessing-andselling-firearms-and-ammunition; Two Men 

Indicted for Firearms Trafficking, DOJ/OPA (Oct. 

28, 2021), available at https://www.justice.gov/ 

usao-edca/pr/two-men-indicted-firearmstrafficking; Tattoo Shop Owner Sentenced to Prison 

for Possessing Unlicensed Firearms at his Business, 

DOJ/OPA (Oct. 28, 2021), available at https://

www.justice.gov/usao-wdpa/pr/tattoo-shop-ownersentenced-prison-possessing-unlicensed-firearmshis-business; Mexican National Charged with 

Possessing Firearms, Methamphetamine in Checked 

Luggage at MSP Airport, DOJ/OPA (Nov. 2, 2021), 

available at https://www.justice.gov/usao-mn/pr/ 

mexican-national-charged-possessing-firearmsmethamphetamine-checked-luggage-msp-airport; 

Lawrence Man Arrested on Firearms and Narcotics 

Charges, DOJ/OPA (Nov. 4, 2021), available at 

https://www.justice.gov/usao-ma/pr/lawrence-manarrested-firearms-and-narcotics-charges; Colchester 

Man Sentenced to 34 Months in Federal Prison for 

Illegally Possessing Machinegun, DOJ/OPA (Nov. 

12, 2021), available at https://www.justice.gov/ 

usao-ct/pr/colchester-man-sentenced-34-monthsfederal-prison-illegally-possessing-machinegun; 

Ocean County Man Charged with Illegally 

Possessing Loaded Semi-Automatic Rifle, DOJ/OPA 

(Nov. 16, 2021), available at https://

www.justice.gov/usao-nj/pr/ocean-county-mancharged-illegally-possessing-loaded-semiautomatic-rifle; New Haven Gang Member Charged 

with Federal Firearm and Narcotics Offenses, DOJ/ 

OPA (Nov. 17, 2021), available at https://

www.justice.gov/usao-ct/pr/new-haven-gangmember-charged-federal-firearm-and-narcoticsoffenses; Edmund H. Mahony, Gang task force 

accuses two East Hartford men of using 3D printers 

to manufacture and sell hard-to-track ‘ghost guns,’ 

Hartford Courant (Jan. 7, 2022), available at https:// 

www.courant.com/news/connecticut/hc-newsghost-gun-arrests-20220107-20220107- 

hqa4ggdygvfxdemh7kihaocqxy-story.html (last 

visited Mar. 22, 2022). 

21 Firearms using 3D-printed components seized 

in Sweden, Armament Research Services (May 19, 

2017), available at https://armamentresearch.com/ 

3d-printed-firearms-seized-in-sweden (last visited 

Mar. 22, 2022); Lizzie Dearden, Use of 3D printed 

guns in German synagogue shooting must act as 

warning to security services, experts say, 

independent.co.uk (Oct. 11, 2019), available at 

https://www.independent.co.uk/news/world/ 

europe/3d-gun-print-germany-synagogue-shootingstephan-balliet-neo-nazi-a9152746.html (last 

visited Mar. 22, 2022); G. Hays, Multiple 3D-printed 

Firearms Seized in Sydney, Australia, Armament 

Research Services (Aug. 11, 2020), available at 

https://armamentresearch.com/multiple-3dprinted-firearms-seized-in-sydney-australia (last 

visited Mar. 22, 2022); Glock ghost guns up for 

grabs on the dark web, Australian National 

University (Mar. 23, 2021), available at https://

www.anu.edu.au/news/all-news/glock-ghost-gunsup-for-grabs-on-the-dark-web (last visited Mar. 22, 

2022); Spain dismantles workshop making 3Dprinted weapons, BBC (Apr. 19, 2021), available at 

https://www.bbc.com/news/world-europe-56798743 

(last visited Mar. 22, 2022); Liam Reilly & Alaa 

Elassar, A Rhode Island man was arrested for 

allegedly selling ‘ghost guns’ and trafficking 

firearms to the Dominican Republic, CNN (Jan. 9, 

2022), available at https://www.cnn.com/2022/01/ 

09/us/rhode-island-ghost-guns-dominican-republic/ 

index.html (last visited Mar. 22, 2022). 

22H.R. Rep. No. 116–88, at 2 (2019). The House 

Report cited a January 11, 2019 Joint Intelligence 

Bulletin issued by DHS, FBI, and NCTC concluding 

that ‘‘these rapidly evolving technologies pose an 

ongoing, metastasizing challenge to law 

enforcement in understanding, tracking, and tracing 

ghost guns,’’ and an April 22, 2019 DHS 

intelligence assessment that ‘‘repeated the warning 

that ghost guns pose an urgent and evolving threat 

to the homeland, particularly in the hands of 

ideologically motivated lone wolf actors.’’ Id. 

23Paul Ingram, CBP: 3–D-printed full-auto rifle 

seized at Lukeville crossing, tucsonsentinel.com 

(Feb. 8, 2016), available at http://

www.tucsonsentinel.com/local/report/020816_3d_

printed_gun/cbp-3-d-printed-full-auto-rifle-seizedlukeville-crossing (last visited Mar. 22, 2022); Dark 

Web Gun Trafficker from Nevada County Pleads 

Guilty to Unlawful Dealing in Firearms, DOJ/OPA 

(June 22, 2018), available at https://

www.justice.gov/usao-edca/pr/dark-web-guntrafficker-nevada-county-pleads-guilty-unlawfuldealing-firearms; Mahita Gajanan, The TSA Has 

Found 3D-Printed Guns at Airport Checkpoints 4 

Times Since 2016, Time (Aug. 2, 2018), available 

at https://time.com/5356179/3d-printed-guns-tsa 

(last visited Mar. 22, 2022); Grass Valley Man 

Sentenced to 5 Years in Prison for Unlawfully 

Manufacturing Ghost Guns and Selling Them on 

Dark Web, DOJ/OPA (Sept. 21, 2018), available at 

https://www.justice.gov/usao-edca/pr/grass-valleyman-sentenced-5-years-prison-unlawfullymanufacturing-ghost-guns-and; Indiana Residents 

Indicted on Terrorism and Firearms Charges, DOJ/ 

OPA (July 11, 2019), available at https://

www.justice.gov/opa/pr/indiana-residents-indictedterrorism-and-firearms-charges; Fishers residents 

indicted on terrorism and firearms charges, DOJ/ 

OPA (July 12, 2019), available at https://

www.justice.gov/usao-sdin/pr/fishers-residentsindicted-terrorism-and-firearms-charges; Brandi 

Vincent, TSA Confiscated 3D-Printed Guns at 

Raleigh-Durham International Airport, nextgov.com 

(Mar. 4, 2020), available at https://

www.nextgov.com/emerging-tech/2020/03/tsaconfiscated-3d-printed-guns-raleigh-durhaminternational-airport/163533 (last visited Mar. 22, 

2022); Man Sentenced for Attempting to Board 

International Flight with a Loaded Firearm, DOJ/ 

OPA (Mar. 12, 2021), available at https://

www.justice.gov/usao-sdca/pr/man-sentencedattempting-board-international-flight-loadedfirearm; Lizzie Dearden, Police issue warning over 

terrorist use of 3D-printed guns as UK neo-Nazi 

jailed, MSN News (June 14, 2021), available at 

https://www.msn.com/en-gb/news/uknews/policeissue-warning-over-terrorist-use-of-3d-printed-gunsas-uk-neo-nazi-jailed/ar-AAL2G36 (last visited Mar. 

22. 2022); Davide Sher, Oceanian media report 

seizures of 3D printed guns, submachine guns, 3D 

Printing Media Network (June 22, 2021), https://

www.3dprintingmedia.network/oceanian-mediareport-seizures-of-3d-printed-guns-submachineguns (last visited Mar. 22, 2022); Dr. Yannick 

Veilleux-Lepage, CTRL, HATE, PRINT: Terrorists 

and the appeal of 3D-printed weapons, 

International Centre for Counter-Terrorism (July 13, 

2021), available at https://icct.nl/publication/ctrlhate-print-terrorists-and-the-appeal-of-3d-printedweapons (last visited Mar. 22, 2022); Chuck Goudie 

et al., Al Qaeda launches 1st public campaign in 

4 years to encourage lone wolf terrorist attacks, 

ABC7 Chicago (July 29, 2021), available at https:// 

abc7chicago.com/al-qaeda-terrorism-terroristattack-inspire-magazine/10918191 (last visited Mar. 

22, 2022); Huder Abbasi, What’s behind far-right 

trend of using 3D tech to make guns?, 

Aljazeera.com (July 31, 2021), available at https:// 

www.aljazeera.com/news/2021/7/31/what-behindfar-right-trend-using-3d-tech-make-guns (last 

visited Mar. 22, 2022); Fergus Hunter, Alleged rightwing extremist charged over blueprint to 3D-print 

a gun, The Sydney Morning Herald (Sept. 13, 2021), 

available at https://www.smh.com.au/national/ 

nsw/alleged-right-wing-extremist-arrested-overblueprint-to-3d-print-a-gun-20210913-p58r80.html 

(last visited Mar. 22, 2022); Mexican National 

Charged with Possessing Firearms, 

Methamphetamine in Checked Luggage at MSP 

Airport, DOJ/OPA (Nov. 2, 2021), available at 

https://www.justice.gov/usao-mn/pr/mexicannational-charged-possessing-firearmsmethamphetamine-checked-luggage-msp-airport. 

24See Cal. Penal Code. sec. 29180 (prohibiting 

ownership of firearms that do not bear a serial 

number or other mark of identification provided by 

the State); Conn. Gen. Stat. sec. 29–36a(a) 

(prohibiting manufacture of firearms without 

permanently affixing serial numbers issued by the 

State); Del. Code Ann. tit. 11 secs. 1459A, 1462 

(prohibiting possession of an unfinished frame or 

receiver with no serial number and untraceable 

firearms); DC Code sec. 7–2504.08(a) (prohibiting 

licensees from selling firearms without serial 

numbers); Haw. Rev. Stat. sec. 134–10.2 

(prohibiting unlicensed persons from producing, 

purchasing, or possessing 3D-printed or parts kit 

firearms without a serial number); Mass. Gen. Laws 

Ch. 269 sec. 11E (prohibiting manufacture or 

delivery of unserialized firearms to licensed dealer); 

N.J. Stat. Ann. sec. 2C:39–3(n) (prohibiting 

possession of firearms manufactured or assembled 

without serial number); N.Y. Penal Law secs. 

265.50, 265.55 (prohibiting manufacture/possession 

of undetectable firearms); R.I. Gen. Laws sec. 11– 

47–8(e) (prohibiting possession of ‘‘a ghost gun or 

an undetectable firearm or any firearm produced by 

a 3D printing process’’); Va. Code. Ann. sec. 18.2– 

308.5 (prohibiting possession of undetectable 

firearms); Wash. Rev. Code sec. 9.41.190 

(prohibiting the manufacture with intent to sell of 

undetectable and untraceable firearms); see also Bill 

to ban ghost guns passes in Maryland House, heads 

to Gov. Hogan’s desk, wjla.com (Mar. 29, 2022), 

available at https://wjla.com/news/local/ghostguns-ban-bill-passes-maryland-house-marylandgovernor-larry-hogan-signs-gun-control (last visited 

Apr. 3, 2022); Zenon Evans, Philadelphia Becomes 

First City To Ban 3D-Printed Gun Manufacturing, 

Reason.com (Nov. 22, 2013), available at https://

reason.com/2013/11/22/philadelphia-becomes-firstcity-to-ban-3 (last visited Mar. 22, 2022); Council 

unanimously approves Ghost Guns Bill, restricting 

the sale [or] transfer of ghost guns to minors, 

Montgomerycountymd.gov (Apr. 6, 2021), available 

at https://www2.montgomerycountymd.gov/ 

mcgportalapps/Press_Detail.aspx?Item_

ID=34040&Dept=1 (last visited Mar. 22, 2022); Chris 

Gros, Mayor Gloria signs ban on ghost guns in San 

Diego, CBS8 (Sept. 23, 2021), available at https:// 

www.cbs8.com/article/news/local/mayor-gloriasigns-ban-on-ghost-guns-in-san-diego/509- 

The problem of untraceable firearms 

being acquired and used by violent 

criminals and terrorists is international 

in scope.21 The NPRM highlighted 

Congress’s concern, based on 

intelligence reports from the 

Department of Homeland Security 

(‘‘DHS’’), the Federal Bureau of 

Investigation (‘‘FBI’’), and the National 

Counterterrorism Center (‘‘NCTC’’), that 

untraceable firearms pose a challenge to 

law enforcement’s ability to investigate 

crimes and that ‘‘wide availability of 

ghost guns and the emergence of 

functional 3D-printed guns are a 

homeland security threat.’’ 22 Numerous 

criminal investigations and studies have 

also demonstrated these concerns,23

while several States and municipalities 

have banned or severely restricted 

unserialized or 3D-printed firearms.24


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24659 

ddd5f49d-29dc-42a6-8f2c-41f17381718f (last visited 

Mar. 22, 2022); Julia Wick, L.A. City Council votes 

to ban ‘ghost guns’, Police1.com (Dec. 1, 2021), 

available at https://www.police1.com/gunlegislation-law-enforcement/articles/la-city-councilvotes-to-ban-ghost-guns-8Rre0xK860ryrYud (last 

visited Mar. 22, 2022); Hannah Metzger, Denver 

outlaws owning, manufacturing ‘ghost guns’ in city, 

denvergazette.com (Jan. 3, 2022), available at 

https://denvergazette.com/news/government/ 

denver-outlaws-owning-manufacturing-ghost-gunsin-city/article_88799392-6d04-11ec-9da0- 

134e7e7be5f2.html (last visited Mar. 22, 2022); 

Jakob Rodgers, Oakland joins growing list of 

California cities to ban ghost guns, 

mercurynews.com (Jan. 18, 2022), available at 

https://www.mercurynews.com/2022/01/18/ 

oakland-joins-growing-list-of-california-cities-toban-ghost-guns (last visited Mar. 22, 2022). 

25See Public Law 90–351, sec. 901(a), 82 Stat. 

212, 225–26 (1968); 18 U.S.C. 922(b)(2) (prohibiting 

licensees from selling or delivering any firearm to 

any person in a State where the purchase or 

possession by such person of such firearm would 

be in violation of any State law or published 

ordinance applicable at the place of sale, delivery, 

or other disposition); 18 U.S.C. 922(t)(2), (4) (NICS 

background check denied if receipt of firearm by 

transferee would violate State law); 18 U.S.C. 

923(d)(1)(F) (requiring license applicants to certify 

compliance with the requirements of State and local 

law applicable to the conduct of business). 

26Fact Sheet, eTrace: Internet-Based Firearms 

Tracing and Analysis, ATF (Sept. 2021), available 

at https://www.atf.gov/resource-center/fact-sheet/ 

fact-sheet-etrace-internet-based-firearms-tracingand-analysis. 

27Licensees must respond to ATF trace requests 

within 24 hours. 18 U.S.C. 923(g)(7); see also J&G 

Sales Ltd. v. Truscott, 473 F.3d 1043, 1045–46 (9th 

Cir. 2007) (describing the tracing process). 

28See 18 U.S.C. 923(c); 27 CFR 478.125a(a)(4) 

(licensed manufacturers, importers, and dealers 

must record in a bound volume a complete 

description of firearms disposed of from their 

personal collections); 18 U.S.C. 923(g)(1)(A), (D); 27 

CFR 478.125(e), (f) (licensed dealer and collector 

disposition records must contain a complete 

description of the firearm); 132 Cong. Rec. 15229 

(1986) (Statement of Rep. Hughes) (‘‘In order for the 

law enforcement Firearm Tracing Program to 

operate, some minimal level of recordkeeping is 

required [for sales from dealers’ personal 

collections]. Otherwise, we will not have tracing 

capability. This provision simply requires that a 

bound volume be maintained by the dealer of the 

sales of firearms which would include a complete 

description of the firearm, including its 

manufacturer, model number, and its serial number 

and the verified name, address, and date of birth of 

the purchaser. This is only a minimal 

inconvenience for the dealer, yet obtaining and 

recording this information is critical to avoid 

serious damage to the Firearm Tracing Program.’’). 

29Source: ATF Office of Strategic Intelligence and 

Information. These numbers (as of January 21, 2022) 

include traces for both U.S. and international law 

enforcement agencies. 

30 27 CFR 478.125(e). 

31 18 U.S.C. 923(g)(1)(A); 27 CFR 478.124. 

32 18 U.S.C. 923(g)(6); 27 CFR 478.39a(b). 

33 18 U.S.C. 923(g)(3)(A); 27 CFR 478.126a. 

Pursuant to 18 U.S.C. 923(g)(5)(A), licensed dealers 

along the Southwest U.S. border are also required 

by demand letter to report to ATF multiple sales of 

certain rifles during five consecutive business days 

to the same person on ATF Form 3310.12, including 

the rifle’s serial number, manufacturer, importer, 

model, and caliber. Also under that statute, licensed 

dealers with 25 or more trace requests with a ‘‘timeto-crime’’ of three years or less must report to ATF 

the acquisition date, model, caliber or gauge, and 

the serial number of a secondhand firearm 

transferred by the dealer. 

34 In United States v. Biswell, 406 U.S. 311, 315– 

16 (1972), the Supreme Court explained that ‘‘close 

scrutiny of [firearms] traffic is undeniably of central 

importance to federal efforts to prevent violent 

crime and to assist the States in regulating the 

firearms traffic within their borders. Large interests 

are at stake, and inspection is a crucial part of the 

regulatory scheme, since it assures that weapons are 

distributed through regular channels and in a 

traceable manner and makes possible the 

prevention of sales to undesirable customers and 

Continued 

Courts have recognized that the 

information licensees are required to 

record and maintain under the GCA 

‘‘enable[s] federal authorities both to 

enforce the law’s verification measures 

and to trace firearms used in crimes.’’ 

Abramski v. United States, 573 U.S. 

169, 173 (2014) (citing H.R. Rep. No. 

1577, 90th Cong., 2d Sess., 14 (1968)). 

At least one court has also concluded 

that ATF has a statutory duty pursuant 

to the GCA to trace firearms to keep 

them out of the hands of criminals and 

other prohibited persons. Blaustein & 

Reich, Inc. v. Buckles, 220 F. Supp. 2d 

535, 537 (E.D. Va. 2002). This duty 

includes assisting State and local law 

enforcement in their efforts to control 

the traffic of firearms within their 

borders.25 Indeed, as of January 2022, 

there are approximately 8,674 law 

enforcement agencies, including 49 

agencies from 46 foreign countries, that 

use eTrace, a web-based application 

administered by ATF that allows 

authorized law enforcement agencies to 

submit and conduct comprehensive 

traces of recovered crime guns and 

develop long-term strategies on how 

best to reduce firearms-related crime, 

firearms trafficking, and violence in 

their communities.26

As discussed in the NPRM, tracing is 

an integral tool for Federal, State, local, 

and international law enforcement 

agencies to utilize in their criminal 

investigations, and the proliferation of 

untraceable firearms severely 

undermines this process. 86 FR at 

27724–25. The NPRM described the 

overall process that ATF engages in 

when tracing firearms submitted by law 

enforcement. Id. at 27724. The 

Department stressed how ATF relies on 

the recordkeeping required to be 

maintained by licensees in order to 

locate the first unlicensed person who 

acquired the recovered firearm from a 

licensed dealer.27 This information can 

help find the perpetrator or provide 

valuable leads that help to solve the 

crime. Thus, for a successful trace to be 

conducted, an accurate firearm 

description is necessary and required to 

be recorded by a person licensed to 

engage in the business of 

manufacturing, importing, or dealing in 

firearms, or by a licensed collector of 

curio or relic firearms, regardless of 

whether it is a business or personal 

firearm of the licensee.28

Because PMFs lack serial numbers 

and other markings from a licensed 

manufacturer, ATF has found it 

extremely difficult to successfully 

complete traces of PMFs. Out of the 

approximately 45,240 submitted traces 

of suspected PMFs mentioned above, 

ATF could only successfully complete 

approximately 445 of those attempted 

traces to an individual unlicensed 

purchaser.29 Successful traces of PMFs 

have been completed in these rare 

instances primarily because licensees 

who acquired PMFs sometimes recorded 

a serial number that had been 

voluntarily engraved by the 

manufacturer on a commercially 

produced handgun slide, barrel, or 

another firearm part, which are not 

required by the GCA to be marked. 

In the NPRM, the Department noted 

that, with the rapid emergence of PMFs 

in recent years, licensees have sought 

clarity from ATF on how PMFs may be 

accepted and recorded. 86 FR at 27724– 

25. Licensees engaged in the business of 

dealing in firearms are subject to various 

recording and reporting requirements, 

including completion of a Firearms 

Acquisition and Disposition Record 

(‘‘A&D Record’’) to record their firearms 

inventory,30 a Firearms Transaction 

Record, ATF Form 4473 (‘‘Form 4473’’), 

for disposition of a firearm to an 

unlicensed person,31 a Federal Firearms 

Licensee Theft/Loss Report, ATF Form 

3310.11, upon discovery of the theft or 

loss of firearms,32 and a Report of 

Multiple Sale or Other Disposition of 

Pistols and Revolvers, ATF Form 

3310.4, to document sales or other 

dispositions of multiple pistols or 

revolvers within five consecutive 

business days to the same person.33

These forms require licensees to record 

the manufacturer and importer (if any), 

model (if designated), serial number, 

type, and caliber or gauge of the firearm. 

As applied to PMFs, licensees 

acquiring them might only record a 

‘‘type’’ of firearm (e.g., pistol, revolver, 

rifle, or shotgun) in their A&D records 

and on Forms 4473. With such limited 

information, it will become increasingly 

difficult, if not impossible, for licensees 

and ATF (during inspections) to match 

accurately and reliably the PMFs in the 

firearms inventory with those recorded 

in required A&D records, or to 

determine whether the PMFs recorded 

as disposed on Forms 4473 are those 

recorded as disposed in the A&D 

records.34 Likewise, licensees and ATF 


jspears on DSK121TN23PROD with RULES2
24660 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

the detection of the origin of particular firearms’’ 

(citation omitted). 35Most states require pawnbrokers to record or 

report any serial number and other identifying 

markings on pawned merchandise so that police 

can determine their origin. See Ala. Code sec. 5– 

19A–3(1); Alaska Stat. sec. 08.76.180(a)(4); Ariz. 

Rev. Stat. sec. 44–1625(C)(5); Colo. Rev. Stat. sec. 

29–11.9–103(1); Conn. Gen. Stat. sec. 21–41(c); Del. 

Code Ann. tit. 24, sec. 2302(a)(1)(b); D.C. Code sec. 

47–2884.11(d); Fla. Stat. sec. 538.04(1)(b)(3), (9); Ga. 

Code sec. 44–12–132(4); Haw. Rev. Stat. sec. 445– 

134.11(c)(10); 205 Ill. Comp. Stat. 510/5(a); Ind. 

Code sec. 28–7–5–19(a)(4); Ky. Rev. Stat. Ann. Sec. 

226.040(1)(d)(7); La. Stat. Ann. sec. 37:1782(16)(a); 

Mass. Gen. Laws ch. 140 sec. 79; Mich. Comp. Laws 

sec. 446.205(5)(1), (4); Minn. Stat. sec. 

325J.04(Sub.1)(1); Miss. Code Ann. sec. 75–67– 

305(1)(a)(iii), (ix); Mo. Rev. Stat. sec. 

367.040(4)(6)(b); Neb. Rev. Stat. sec. 69–204(3); 

N.M. Stat. Ann. sec. 56–12–9(A)(3); N.C. Gen. Stat. 

sec. 66–391(b)(1); Ohio Rev. Code Ann. sec. 

4727.07; Okla. Stat. tit. 59 sec. 1509(D)(h); S.C. 

Code Ann. sec. 40–39–80(B)(1)(l)(iii), (ix); Tenn. 

Code Ann. sec. 45–6–209(b)(1)(C), (H); Tex. Fin. 

Code Ann. sec. 371.157(4); Utah Code Ann. sec. 13– 

32a–104(1)(h)(i)(A); Va. Code Ann. sec. 54.1– 

4009(A)(1); Wash. Rev. Code sec. 19.60.020(1)(e); 

W. Va. Code sec. 47–26–2(b)(1); Wis. Stat. sec. 

134.71(8)(c)(2). 

36See United States v. Marzzarella, 614 F.3d 85, 

100 (3d Cir. 2010) (‘‘The direct tracing of the chain 

of custody of firearms involved in crimes is one 

useful means by which serial numbers assist law 

enforcement. But serial number tracing also 

provides agencies with vital criminology statistics— 

including a detailed picture of the geographical 

source areas for firearms trafficking and ‘‘time-tocrime’’ statistics which measure the time between 

a firearm’s initial retail sale and its recovery in a 

crime—as well as allowing for the identification of 

individual dealers involved in the trafficking of 

firearms and the matching of ballistics data with 

recovered firearms’’ (footnotes omitted).); Following 

the Gun: Enforcing Federal Laws Against Firearms 

Traffickers, ATF at 1, 26 (2000) (serial number 

obliteration is a clear indicator of firearms 

trafficking to, among other criminals, armed 

narcotics traffickers). 

37See, e.g., Abramski v. United States, 573 U.S. 

169, 192 (2014); Marshall v. Virginia, 822 SE2d 389, 

392–93 (Va. Ct. App. 2019); Shirley v. Glass, 297 

Kan. 888 (2013); Pennsylvania v. Baxter, 956 A.2d 

465, 472 (Pa. Super. Ct. 2008). 

38See, e.g., United States v. Powell, 467 F. Supp. 

3d 360, 368, 374 (E.D. Va. 2020) (indictment 

charging false statements on ATF Form 4473 in 

connection with the purchase of specific handguns 

listed by date of purchase, make, caliber, model, 

serial number, and name of FFL); United States v. 

McCurdy, 634 F. Supp. 2d 118, 121–22, 126 (D. Me. 

2009) (denial of a motion for a new trial discussing 

whether the firearm sold as documented on the 

ATF Form 4473 and the firearm introduced at trial 

were the same). 

39The lack of firearm description information in 

theft/loss reports makes it difficult for ATF to 

match recovered firearms with those reported as 

lost or stolen, thereby hindering ATF’s efforts to 

enforce the numerous provisions of the GCA that 

prohibit thefts. See 18 U.S.C. 922(i) (transporting or 

shipping stolen firearms in interstate or foreign 

commerce); 18 U.S.C. 922(j) (receiving, possessing, 

concealing, storing, bartering, selling, disposing, or 

pledging or accepting as security for a loan any 

stolen firearm which has moved in interstate or 

foreign commerce); 18 U.S.C. 922(u) (stealing a 

firearm that has been shipped or transported in 

interstate or foreign commerce from the person or 

premises of an FFL); 18 U.S.C. 924(l) (stealing a 

firearm which is moving in or has moved in 

interstate commerce); 18 U.S.C. 924(m) (stealing a 

firearm from a licensee). 

40A firearm ‘‘muffler or silencer’’ is defined to 

include ‘‘any combination of parts’’ designed and 

intended for the use in assembling or fabricating a 

firearm silencer or muffler and ‘‘any part intended 

only for use in such assembly or fabrication.’’ 18 

U.S.C. 921(a)(24); 26 U.S.C. 5845(a)(7); 27 CFR 

478.11, 479.11. This rule defines the term 

‘‘complete muffler or silencer device’’ not to exempt 

individual silencer parts from the definition of 

firearm ‘‘muffler or silencer’’ subject to the 

requirements of the NFA, but to advise industry 

members when those individual silencer parts must 

be marked and registered in the NFRTR when they 

are used in assembling, fabricating, or repairing a 

muffler or silencer device. 

41See 27 CFR 479.101(b), 478.92(a)(4)(iii), 

479.102(f)(1). 

will have difficulty accurately 

determining which PMFs were stolen or 

lost from inventory. It will also be 

difficult for police to locate stolen PMFs 

in the business inventories of 

pawnbrokers, for example,35 or to return 

any recovered stolen or lost PMFs to 

their rightful owners. 

Assuming a PMF can be successfully 

traced to a Federal firearms licensee 

(‘‘FFL’’) or that a correct Form 4473 can 

be located, the NPRM explained that the 

ATF Form 4473 is the primary evidence 

used to prosecute straw purchasers who 

buy firearms from FFLs typically on 

behalf of prohibited persons, such as 

felons or illegal firearms traffickers, and 

other persons who could use the 

firearms to commit violent crimes.36

The form is typically the key evidence 

that the straw purchaser who bought the 

firearm (and who can pass a background 

check) made a false statement to the FFL 

concerning the identity of the actual 

purchaser when acquiring that firearm, 

in violation of 18 U.S.C. 922(a)(6) and 

924(a)(1)(A), or State law.37 But as 

unmarked and difficult-to-trace PMFs 

are transacted throughout the 

commercial marketplace, law 

enforcement will have difficulties 

prosecuting straw purchasers for making 

false statements because it will be 

harder to prove that the firearms 

acquired under false pretenses on a 

Form 4473 were the ones found in the 

hands of the true purchaser.38 Likewise, 

the absence of identifying firearm 

information on multiple sales forms and 

theft/loss reports makes it more difficult 

for ATF to identify firearms traffickers 

and thieves.39

C. Advanced Notice of Proposed 

Rulemaking on Identification Markings 

Placed on Firearm Silencers and 

Firearm Mufflers 

The NPRM noted that on May 4, 2016, 

the Department published an advance 

notice of proposed rulemaking 

(‘‘ANPRM’’) in the Federal Register. 86 

FR 27728 n.50 (citing 81 FR 26764). The 

ANPRM was issued in response to a 

petition filed on behalf of the National 

Firearms Act Trade and Collectors 

Association (‘‘NFATCA’’), a trade group 

representing the firearms and import 

community. The petitioner requested 

that the relevant regulations be 

amended to require that a silencer be 

marked on the outer tube as opposed to 

other locations, such as an end cap that 

might be damaged when a projectile 

passes through it, unless a variance is 

granted by the Director on a case-bycase basis for good cause. ATF found 

that the petitioner raised valid concerns. 

Under the GCA, licensed 

manufacturers and importers must 

identify the frame or receiver of each 

firearm, including a firearm muffler or 

silencer, with a serial number in 

accordance with regulations. 18 U.S.C. 

921(a)(3)(C), 923(i). The NFA requires 

firearm manufacturers, importers, and 

makers to identify each firearm, 

including a firearm muffler or silencer, 

with a serial number and such other 

identification as may be prescribed by 

regulations. 26 U.S.C. 5842(a), 

5845(a)(7). Because the NFA defines 

each individual part of a firearm muffler 

or silencer as a ‘‘firearm’’ 40 that must be 

registered in the NFRTR, the regulations 

currently assume that every part defined 

as a silencer must be marked in order 

to be registered, and expressly require 

that each part be marked whenever sold, 

shipped, or otherwise disposed of even 

though it may have been installed by a 

qualified licensee within a complete 

muffler or silencer device.41

The ANPRM explained that, along 

with industry members, ATF considers 

the term ‘‘outer tube’’ to mean the 

largest external part of a silencer and is 

that portion of a silencer that 

encapsulates all components of the 

silencing unit, and which contains and 

controls the expansion of the escaping 

gases. 81 FR at 26765. ATF explained 

that placing all required markings on 

the outer tube of a completed firearm 

silencer or firearm muffler is the 

accepted industry standard. In addition, 

ATF discussed that requiring 

identification markings to be placed on 

a single part provides consistency of 

markings throughout the industry and 

eliminates the need to re-mark a device 

in the event an end cap bearing the 

markings is damaged and requires 

replacement. ATF believed that a more 

specific marking requirement for firearm 

silencers, such as the outer tube, would 

lead to greater uniformity, improve 

public safety, and decrease firearms 

crimes, including firearms trafficking. 

See id. 

The ANPRM was used to solicit 

comments to determine if an 

amendment to the regulations that 

would require placement of 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24661 

42Numerous courts have held that weapons 

designed to expel a projectile by the action of an 

explosive are ‘‘firearms’’ under 18 U.S.C. 

921(a)(3)(A) even if they cannot expel a projectile 

in their present form or configuration. See, e.g., 

United States v. Hardin, 889 F.3d 945, 946–47, 949 

(8th Cir. 2018) (pistol with broken trigger and 

numerous missing internal parts was a weapon 

designed to expel a projectile by the action of an 

explosive); United States v. Dotson, 712 F.3d 369, 

370–71 (7th Cir. 2013) (saying, in ruling that a 

pistol with corroded, missing, and broken 

components was a ‘‘firearm,’’ that ‘‘[a]n airplane is 

designed to fly; a defect in manufacture or 

maintenance that prevents it from flying does not 

alter its design’’); United States v. Davis, 668 F.3d 

576, 577 (8th Cir. 2012) (holding that a pistol with 

no trigger was a ‘‘firearm’’ within the meaning of 

section 2K2.1(a)(3)(A)(i) of the Sentencing 

Guidelines and applying ‘‘the same reasoning [that 

courts have applied in section 921(a)(3) cases] to 

Guidelines provisions that incorporate the 

§ 921(a)(3) definition’’); United States v. Counce, 

445 F.3d 1016, 1018 (8th Cir. 2006) (handgun with 

missing safety); United States v. Rivera, 415 F.3d 

284, 285–87 (2d Cir. 2005) (pistol with a broken 

firing pin and flattened firing-pin channel); United 

States v. Morales, 280 F. Supp. 2d 262, 272–73 

(S.D.N.Y. 2003) (partially disassembled Tec-9 pistol 

was designed to expel a projectile); United States 

v. Adams, 137 F.3d 1298, 1300 & n.2 (11th Cir. 

1998) (potentially inoperable shotgun); United 

States. v. Brown, 117 F.3d 353 (7th Cir. 1997) 

(holding that a gun with no firing pin was a 

‘‘firearm’’ within the meaning of section 

2B3.1(b)(2)(C) of the Sentencing Guidelines, and 

discussing analogous cases interpreting section 

921(a)(3)(A)); United States v. Reed, 114 F.3d 1053 

(10th Cir. 1997) (shotgun with broken breech bolt); 

United States v. Hunter, 101 F.3d 82 (9th Cir. 1996) 

(holding that the sentence enhancement for use of 

a semiautomatic weapon in section 924(c) applied 

to a pistol with broken firing pin); United States v. 

Yannott, 42 F.3d 999, 1005–07 (6th Cir. 1994) 

(shotgun with broken firing pin); United States v. 

Ruiz, 986 F.2d 905, 910 (5th Cir. 1993) (revolver 

with hammer filed down); United States v. York, 

830 F.2d 885, 891 (8th Cir. 1987) (revolver with no 

firing pin and cylinder did not line up with barrel); 

United States v. Thomas, No. 17–194 (RDM), 2019 

WL 4095569, at *4 (D.D.C. Aug. 29, 2019) (in ruling 

that a revolver missing its hammer, hammer screw, 

trigger, cylinder stop, hand, ejector rod housing, 

base pin, screw, nut, spring, loading gate detent and 

spring and miscellaneous screws was a ‘‘firearm,’’ 

the court said: ‘‘[t]he Titanic was, after all, 

‘designed’ to be unsinkable’’). But see Dotson, 712 

F.3d at 371 (a Beretta pistol redesigned to be a 

cigarette lighter); Rivera, 415 F.3d at 286–87 (‘‘[A] 

gun with a barrel filled with lead, maybe for use 

as a theatrical prop, might perhaps no longer be 

deemed ‘designed to’ or ‘readily be converted’ to 

fire a bullet.’’); United States v. Wada, 323 F. Supp. 

2d 1079 (D. Or. 2004) (firearms redesigned as 

ornaments that ‘‘would take a great deal of time, 

expertise, equipment, and materials to attempt to 

reactivate’’ were no longer designed to expel a 

projectile by the action of an explosive, and could 

not readily be converted to do so). 

43See, e.g., United States v. Mullins, 446 F.3d 

750, 756 (8th Cir. 2006) (starter gun that can be 

modified in less than one hour by a person without 

any specialized knowledge to fire may be 

considered ‘‘readily convertible’’ under the GCA); 

United States v. 16,179 Molso Italian .22 Caliber 

Winlee Derringer Convertible Starter Guns, 443 F.2d 

463 (2d Cir. 1971) (starter guns converted in no 

more than 12 minutes to fire live ammunition were 

readily convertible under the GCA); United States 

v. Morales, 280 F. Supp. 2d 262, 272–73 (S.D.N.Y. 

2003) (partially disassembled Tec-9 pistol that 

could be assembled within a short period of time 

could readily be converted to expel a projectile). Cf. 

United States v. Dodson, 519 F. App’x 344, 352– 

53 (6th Cir. 2013) (gun that was restored with 90 

minutes of work, using widely available parts and 

equipment and common welding techniques, fit 

comfortably within the readily restorable standard 

of 26 U.S.C. 5845(b)); United States v. TRW Rifle 

7.62×51mm Caliber, One Model 14 Serial 593006, 

Continued 

identification markings on the outer 

tube of firearm silencers and mufflers 

was warranted. In response to the 

ANPRM, ATF received 48 comments. A 

few commenters supported issuance of 

a proposed rule because they believed it 

would not violate any constitutional 

rights under the Second Amendment, 

would enhance public safety for the 

reasons ATF stated, and would reduce 

confusion within the industry without 

being a financial burden because it is 

already a standard practice with many 

manufacturers. The majority of 

commenters expressed opposition and 

did not want ATF to proceed with any 

further rulemaking. Specific reasons for 

their objection to a proposed rule 

included a belief that: (1) ATF lacks 

legal authority to specify where 

markings on silencers must be located 

and that such a rule would violate the 

Second Amendment; (2) the initial 

NFATCA petition is outdated; (3) there 

is no data to support that a new rule 

would enhance public safety or reduce 

firearms trafficking; (4) a new regulation 

is unnecessary as the industry is already 

complying; (5) it is not feasible to 

comply with marking on the outer tube 

of the silencer with specific designs; (6) 

the proposed idea hinders technological 

advances and future designs; (7) it 

would create confusion and definitional 

problems because the definition of outer 

tube is outdated; and (8) the industry 

and public would incur financial 

burdens. 

Other commenters offered suggestions 

about outer tube replacement options 

especially because silencer tubes wear 

out over time. They suggested that a rule 

would be reasonable if ATF authorizes 

manufacturers to repair or replace 

damaged silencer tubes and engrave the 

new tube with the original serial 

number. Commenters also suggested 

alternative locations for silencer 

markings such as on end caps. They 

believed that markings should be placed 

on the major portion of the silencer, 

which could be the end cap or any 

section of the tube. They stressed that 

the outer tube is thin and there is a 

greater risk of burning through the metal 

when engraving and that end caps have 

greater thickness to work with when 

engraving. 

Based on further review and the 

comments received in response to the 

ANPRM, ATF incorporated a proposed 

definition of ‘‘frame or receiver’’ as it 

applies to firearm mufflers and silencers 

in the NPRM to clarify when and how 

silencer parts are to be marked and 

registered. 86 FR 27720. 

III. Notice of Proposed Rulemaking 

On May 21, 2021, the Department 

published in the Federal Register an 

NPRM entitled ‘‘Definition of ‘Frame or 

Receiver’ and Identification of 

Firearms,’’ 86 FR 27720, proposing 

changes to various regulations in 27 

CFR parts 447, 478, and 479. Overall, 

the NPRM proposed amending ATF’s 

regulations to clarify the definition of 

‘‘firearm’’ and to provide a more 

comprehensive definition of ‘‘frame or 

receiver’’ so that these terms more 

accurately reflect how most modern-day 

firearms are produced and function, and 

so that the courts, the firearms industry, 

and the public at large would no longer 

misinterpret the term to mean that most 

firearms in circulation have no parts 

identifiable as a frame or receiver. The 

NPRM also proposed new terms and 

definitions to account for technological 

developments and modern terminology 

in the firearms industry, as well as 

proposed amendments to the marking 

and recordkeeping requirements that 

would be necessary to implement these 

definitions. 

A. Definition of ‘‘Firearm’’ 

In the NPRM, the Department 

proposed adding a sentence at the end 

of the definition of ‘‘firearm’’ in 27 CFR 

478.11 to reflect existing case law, 

providing that ‘‘[t]he term shall include 

a weapon parts kit that is designed to or 

may readily be assembled, completed, 

converted, or restored to expel a 

projectile by the action of an explosive.’’ 

However, the proposed amendment was 

not intended to affect the classification 

of a weapon, including a weapon parts 

kit, in which the frame or receiver (as 

defined in the proposed rule) of such 

weapon is properly destroyed. See 86 

FR at 27726, 27729–30. Therefore, 

another sentence was proposed to be 

added at the end of the definition of 

‘‘firearm’’ to provide that ‘‘[t]he term 

shall not include a weapon, including a 

weapon parts kit, in which each part 

defined as a frame or receiver of such 

weapon is destroyed.’’ Id. at 27726. 

The Department explained in the 

NPRM that ‘‘firearm’’ as defined under 

the GCA, 18 U.S.C. 921(a)(3) and 27 CFR 

478.11, includes inoperable weapons 

even though they will not expel a 

projectile by the action of an explosive 

at the time of sale or distribution if they 

are ‘‘designed to’’ 42 or ‘‘may readily be 

converted’’ 43 to expel a projectile by the 


jspears on DSK121TN23PROD with RULES2
24662 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

447 F.3d 686, 692 (9th Cir. 2006) (a two-hour 

restoration process using ordinary tools, including 

a stick weld, is within the ordinary meaning of 

‘‘readily restored’’); United States v. One TRW, 

Model M14, 7.62 Caliber Rifle, 441 F.3d 416, 422– 

24 (6th Cir. 2006) (‘‘[T]he Defendant weapon here 

had all of the necessary parts for restoration and 

would take no more than six hours to restore.’’); 

United States v. Woods, 560 F.2d 660, 664 (5th Cir. 

1977) (holding that a weapon was a shotgun within 

the meaning of 26 U.S.C. 5845(d) and stating ‘‘[t]he 

fact that the weapon was in two pieces when found 

is immaterial considering that only a minimum of 

effort was required to make it operable.’’); United 

States v. Smith, 477 F.2d 399, 400–01 (8th Cir. 

1973) (machinegun that would take around an 

eight-hour working day in a properly equipped 

machine shop was readily restored to shoot); United 

States v. Catanzaro, 368 F. Supp. 450, 453 (D. 

Conn. 1973) (a sawed-off shotgun was ‘‘readily 

restorable to fire’’ where it could be reassembled in 

one hour and the necessary missing parts could be 

obtained at a Smith & Wesson plant). But see United 

States v. Seven Miscellaneous Firearms, 503 F. 

Supp. 565, 574–75 (D.D.C. 1980) (weapons could 

not be ‘‘readily restored to fire’’ when restoration 

required master gunsmith in a gun shop and 

$65,000 worth of equipment and tools). 

44See, e.g., United States v. Wick, 697 F. App’x 

507, 508 (9th Cir. 2017) (complete UZI parts kits 

‘‘could ‘readily be converted to expel a projectile by 

the action of an explosive,’ meeting the statute’s 

definition of firearm under § 921(a)(3)(A)’’ because 

the ‘‘kits contained all of the necessary components 

to assemble a fully functioning firearm with relative 

ease’’); United States v. Stewart, 451 F.3d 1071, 

1072–73, 1073 n.2 (9th Cir. 2006) (upholding 

district court’s finding that .50 caliber rifle kits with 

incomplete receivers were ‘‘firearms’’ under section 

921(a)(3)(A) because they could easily be converted 

to expel a projectile); United States v. 

Theodoropoulos, 866 F.2d 587, 595 n.3 (3d Cir. 

1989), overruled in part on other grounds by United 

States v. Price, 76 F.3d 526, 528 (3d Cir. 1996) 

(disassembled machine pistol that that could easily 

be made operable was a firearm under section 

921(a)(3)(A)); United States v. Morales, 280 F. Supp. 

2d 262, 272–73 (S.D.N.Y. 2003) (partially 

disassembled Tec-9 pistol that could be assembled 

within short period of time could readily be 

converted to expel a projectile was a firearm under 

section 921(a)(3)(A)); United States v. Randolph, 

No. 02 CR. 850–01 (RWS), 2003 WL 1461610, at *2 

(S.D.N.Y. Mar. 20, 2003) (gun consisting of 

‘‘disassembled parts with no ammunition, no 

magazine, and a broken firing pin, making it 

incapable of being fired without replacement or 

repair’’ was a ‘‘firearm’’ under section 921(a)(3)(A) 

because it could be readily converted to expel a 

projectile and included the frame or receiver of 

such a weapon); cf. United States v. Annis, 446 F.3d 

852, 857 (8th Cir. 2006) (partially disassembled rifle 

that could easily be made operational was a firearm 

under sentencing guidelines); United States v. 

Ryles, 988 F.2d 13, 16 (5th Cir. 1993) (same with 

disassembled shotgun that could have been readily 

converted to an operable firearm); Enamorado v. 

United States, No. C16–3029–MWB, 2017 WL 

2588428, at *6 (N.D. Iowa June 14, 2017) (same with 

disassembled .45 caliber handgun that could easily 

be reassembled). 

45The prefatory paragraph to the definitional 

sections in the GCA and NFA regulations explain 

that ‘‘[t]he terms ‘includes’ and ‘including’ do not 

exclude other things not enumerated which are in 

the same general class or are otherwise within the 

scope thereof.’’ 27 CFR 478.11, 479.11. 

action of an explosive. Weapon parts 

kits, or aggregations of weapon parts, 

some of which contain all of the 

components necessary to complete a 

functional weapon within a short period 

of time, have been increasingly sold to 

individuals either directly from 

manufacturers of the kits or retailers, 

without background checks or 

recordkeeping. 86 FR at 27726. Some of 

these firearm kits include jigs, 

templates, and tools that allow the 

purchaser to complete the weapon fairly 

or reasonably efficiently, quickly, and 

easily to a functional state. Such 

weapon parts kits or aggregations of 

weapon parts that are designed to or 

may readily be converted to expel a 

projectile by the action of an explosive 

are also ‘‘firearms’’ under 18 U.S.C. 

921(a)(3)(A).44 This proposed addition 

makes explicit that manufacturers and 

sellers of such kits or aggregations of 

weapon parts are subject to the same 

regulatory requirements applicable to 

the manufacture or sale of fully 

completed and assembled firearms. See 

86 FR at 27726. 

B. Definition of ‘‘Frame or Receiver’’ 

The Department proposed to revise 

the definition of ‘‘frame or receiver’’ 

with a multi-part definition. First 

proposed was a general definition of 

‘‘frame or receiver’’ with nonexclusive 

examples that illustrated the definition. 

This was followed by four proposed 

supplements, described below, that 

further explained the meaning of the 

term ‘‘frame or receiver’’ for certain 

firearm designs and configurations. 

Although the proposed definition was 

intended to more broadly define the 

term ‘‘frame or receiver’’ than the 

current definition, it was not intended 

to alter any prior determinations by ATF 

regarding which specific part of a given 

weapon it considered the frame or 

receiver. The NPRM also proposed to 

codify in the regulations the factors ATF 

considers when classifying the frame or 

receiver of a firearm. 

1. General Definition of ‘‘Frame or 

Receiver’’ 

As a threshold matter, the NPRM 

proposed that the new definition, with 

a partial exception for an internal frame 

or chassis, make clear that each frame or 

receiver be visible to the exterior when 

the complete weapon is assembled so 

that licensees and law enforcement can 

quickly and easily identify the 

markings. Next, the NPRM proposed 

defining the term ‘‘frame or receiver’’ 

more broadly as a part that provides 

housing or a structure designed to hold 

or integrate any fire control component, 

which would have included, at a 

minimum, any housing or holding 

structure for a hammer, bolt, bolt 

carrier, breechblock, cylinder, trigger 

mechanism, firing pin, striker, or slide 

rails. However, the proposed definition 

would not have been limited to those 

particular fire control components 45

and was proposed to be general enough 

to encompass changes in technology 

and parts terminology. For further 

clarity, four nonexclusive examples 

with illustrations of common singleframed firearms were provided. See 86 

FR at 27727, 27742. Finally, the 

proposed definition stated that persons 

who may acquire or possess a part now 

defined as a frame or receiver that is 

identified with a serial number must 

presume, absent an official 

determination by ATF or other reliable 

evidence to the contrary, that the part is 

a firearm frame or receiver without 

further guidance. 

2. Definition of ‘‘Firearm Muffler or 

Silencer Frame or Receiver’’ 

The first proposed supplement to 

define the term ‘‘frame or receiver’’ as 

it applies to a ‘‘firearm muffler or 

silencer frame or receiver’’ and to add 

a new term ‘‘complete muffler or 

silencer device’’ is further discussed in 

Section III.D of this preamble. The 

NPRM proposed that in the case of a 

firearm muffler or firearm silencer, the 

frame or receiver is a part of the firearm 

that is visible from the exterior of a 

completed device and provides a 

housing or a structure designed to hold 

or integrate one or more essential 

internal components of the device. 

As described in Section II.C of this 

preamble, the GCA’s marking 

requirement and the GCA/NFA’s 

definition of firearm ‘‘muffler or 

silencer’’ (sometimes referred to as a 

‘‘sound suppressor’’) and its marking 

requirements have caused confusion 

and concern among many silencer 

manufacturers over the years. The 

NPRM explained that some silencer 

parts defined as ‘‘silencers,’’ such as 

baffles, are difficult for manufacturers to 

mark and listed examples of the ATF 

forms that manufacturers would have 

difficulty filing and processing in a 

timely manner. 86 FR at 27728. The 

Department also explained that it makes 

little sense to mark all silencer parts for 

tracing purposes when the outer tube or 

housing of the complete device is 

marked and registered. Id. at 27727–28. 

For these reasons, the new definitions 

were proposed to clarify for 

manufacturers and makers of complete 

muffler or silencer devices that they 

need only mark the one part of the 

device defined as the frame or receiver 

under the proposed rule. However, 

individual muffler or silencer parts were 

proposed to be marked if they are 

disposed of separately from a complete 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24663 

46This rule is consistent with ATF enforcement 

policy. See footnote 58, infra. 

47The term ‘‘80% receiver’’ is a term used by 

some industry members, the public, and the media 

to describe a frame or receiver that has not yet 

reached a stage of manufacture to be classified as 

a ‘‘frame or receiver’’ under Federal law. However, 

that term is neither found in Federal law nor 

accepted by ATF. 

48See 86 FR at 27729 n.55; see also Gene 

Johnson, Felon on supervision accused of having 

‘ghost gun’ arsenal, Associated Press (Feb. 28, 

2020), available at https://apnews.com/article/ 

cc61d48e83a2c8113cdb1e1ed6fe6006 (last visited 

Mar. 23, 2022); Sarah Cassi, Lehigh Valley felon was 

using 3D printer to make ‘ghost guns’ at home, Pa. 

attorney general says,LehighValleyLive.com (June 

29, 2021), available at https://www.lehigh

valleylive.com/northampton-county/2021/06/ 

lehigh-valley-felon-was-using-3d-printer-to-makeghost-guns-at-home-pa-attorney-general-says.html 

(last visited Mar. 23, 2022); Deputy recovers ‘ghost 

gun’ from convicted felon during traffic stop, 

Fontana Herald News (Aug. 10, 2021), available at 

https://www.fontanaheraldnews.com/news/inland_

empire_news/deputy-recovers-ghost-gun-fromconvicted-felon-during-traffic-stop/article_3cfe0fd0- 

f4a3-11eb-bd31-03979dc83307.html (last visited 

Mar. 23, 2022); Parolee Arrested With AR–15 Ghost 

Gun, Fake Law Enforcement Badge, NBC Palm 

Springs (Aug. 13, 2021), available at https://

nbcpalmsprings.com/2021/08/13/parolee-arrestedwith-ar-15-ghost-gun-fake-law-enforcement-badge 

(last visited Mar. 23, 2022); Georgetown Arrest of a 

Felon Leads to Recovery of Ghost Gun, Seattle 

Police Department (Nov. 8, 2021), available at 

https://spdblotter.seattle.gov/2021/11/08/ 

georgetown-arrest-of-a-felon-leads-to-recovery-ofghost-gun (last visited Mar. 23, 2022). 

49As used in this rule, the term ‘‘primordial’’ 

refers to an item, such as an unmachined block of 

metal, liquid polymer, or other raw material that is 

in its original natural form or at an early stage of 

development without substantial processing. See 

Primordial, Oxford English Dictionary, available at 

https://www.oed.com/view/Entry/151373?redirected

From=primordial#eid (last visited Mar. 23, 2022) 

(‘‘that [which] constitutes the origin or starting 

point from which something else is derived or 

developed’’). 

50See 86 FR at 27729, 27746. 

device unless transferred by 

manufacturers qualified under the NFA 

to other qualified licensees for the 

manufacture or repair of complete 

devices.46

3. Definition of ‘‘Split or Modular Frame 

or Receiver’’ 

The second proposed supplement to 

the general definition sought to capture 

the majority of firearms that now use a 

split design as discussed above. It 

sought to clarify that even though a 

firearm, including a silencer, may have 

more than one part that falls within the 

definition of ‘‘frame or receiver,’’ ATF 

may classify a specific part or parts to 

be the ‘‘frame or receiver’’ of a particular 

weapon. It then set forth the various 

factors ATF would consider in making 

this determination with no single factor 

controlling. See 86 FR at 27728–29, 

27743. It also proposed the clarification 

that ‘‘[f]rames or receivers of different 

weapons that are combined to create a 

similar weapon each retain their 

respective classifications as frames or 

receivers provided they retain their 

original design and configuration.’’ Id. 

at 27734. 

To ensure that the proposed 

definition of ‘‘split or modular frame or 

receiver’’ did not affect existing ATF 

classifications that specified a single 

component as the frame or receiver, the 

definition included a nonexclusive list 

of common weapons with a split or 

modular frame or receiver configuration 

for which ATF previously determined a 

specific part to be the frame or receiver. 

See id. at 27729, 27743–46. The NPRM 

explained that a manufacturer or 

importer of one of these firearm designs, 

as they would exist as of the final rule’s 

date of publication, could refer to this 

list to know which part is the frame or 

receiver, thereby allowing the 

manufacturer or importer to mark a 

single part without seeking a 

determination from ATF. However, if 

there was to be a present or future split 

or modular design for a firearm that was 

not comparable to an existing 

classification, then the proposed 

definition of ‘‘frame or receiver’’ would 

advise, absent a variance or 

classification from ATF, that more than 

one part is the frame or receiver subject 

to marking and other requirements. 

4. Definition of ‘‘Partially Complete, 

Disassembled, or Inoperable Frame or 

Receiver’’ 

The third supplement proposed to 

define ‘‘frame or receiver’’ as including 

frames or receivers that are partially 

complete, disassembled, or inoperable, 

or a frame or receiver that has reached 

a stage in manufacture where it may 

readily be completed, assembled, 

converted, or restored to a functional 

state. The NPRM stated that, to 

determine this status, ‘‘the Director may 

consider any available instructions, 

guides, templates, jigs, equipment, tools, 

or marketing materials.’’ 86 FR at 27729, 

27746. ‘‘Partially complete,’’ for 

purposes of this definition, was 

proposed to mean a forging, casting, 

printing, extrusion, machined body, or 

similar article at a stage in manufacture 

where it is clearly identifiable as an 

unfinished component part of a weapon. 

The NPRM explained that this 

supplemental definition aimed to 

address when an object becomes a frame 

or receiver such that it is a regulated 

article. The NPRM stated that partially 

complete or unassembled frames or 

receivers, commonly called ‘‘80% 

receivers,’’ 47 are often sold in kits 

where the frame or receiver can readily 

be completed or assembled to a 

functional state. See id. at 27729 n.54. 

The Department stated that the 

supplemental definition is necessary for 

clarity because companies are not 

running background checks or 

maintaining transaction records when 

they manufacture and sell these kits. 

Accordingly, prohibited persons have 

easily obtained them 48 and, when 

recovered, they are nearly impossible to 

trace. The proposed definition also 

sought to make clear that unformed 

blocks of metal, and other similar 

articles only in a primordial state 49

would not—without more processing— 

be considered a ‘‘partially complete’’ 

frame or receiver that is captured under 

the definition of ‘‘frame or receiver.’’ 

5. Definition of ‘‘Destroyed Frame or 

Receiver’’ 

The fourth supplement proposed to 

exclude from the definition of ‘‘frame or 

receiver’’ any frame or receiver that has 

been destroyed. This proposed 

definition described a destroyed frame 

or receiver as one permanently altered 

not to provide housing or a structure 

that may hold or integrate any fire 

control or essential internal component, 

and that may not readily be assembled, 

completed, converted, or restored to a 

functional state. The proposed 

definition set forth nonexclusive 

acceptable methods of destruction, 

which had been provided by ATF in its 

past guidance.50

C. Definition of ‘‘Readily’’ 

The Department proposed to add the 

term ‘‘readily’’ to 27 CFR 478.11 and 

479.11 and define it as ‘‘a process that 

is fairly or reasonably efficient, quick, 

and easy, but not necessarily the most 

efficient, speedy, or easy process.’’ 86 

FR at 27730, 27747, 27751. It further 

listed factors relevant in applying this 

proposed definition, such as time, ease, 

expertise, equipment, availability, 

expense, scope, and feasibility, with 

brief examples describing these factors. 

Id. The proposed definitions and factors 

are based on case law interpreting ‘‘may 

readily be converted to expel a 

projectile’’ in 18 U.S.C. 921(a)(3)(A) and 

‘‘can be readily restored to shoot’’ in 26 

U.S.C. 5845(b)–(d). See id. at 27730 & 

n.58. The NPRM explained that defining 

the term ‘‘readily’’ was necessary to 

determine when a weapon, including a 

weapon parts kit, a partially complete or 

damaged frame or receiver, or an 

aggregation of weapon parts becomes a 

‘‘firearm’’ regulated under the GCA and 

NFA. 


jspears on DSK121TN23PROD with RULES2
24664 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

51The Federal Firearms Act of 1938 (repealed), 

the predecessor to the GCA, made it unlawful for 

a person to receive in interstate or foreign 

commerce a firearm that had the manufacturer’s 

serial number removed, obliterated, or altered. 15 

U.S.C. 902(i) (1940). Regulations promulgated to 

implement this law required each firearm 

manufactured after July 1, 1958, to be identified 

with the name of the manufacturer or importer, a 

serial number, caliber, and model. However, there 

was an exception from the serial number and model 

requirements for any shotgun or .22 caliber rifle 

unless that firearm was also subject to the NFA. 26 

CFR 177.50 (1959) (rescinded). 

52The term ‘‘gunsmith’’ is not used in the GCA; 

however, the Firearm Owners’ Protection Act, 

Public Law 99–308 (1986), amended the GCA to 

define ‘‘engaged in the business’’ as applied to 

dealers to clarify when gunsmiths must have a 

license. See 18 U.S.C. 921(a)(11)(B), (a)(21)(D); 132 

Cong. Rec. 9603–04 (1986) (statement of Sen. 

McClure). 

53This rule would supersede ATF Ruling 2010– 

10, which allows gunsmiths under specified 

conditions to engage in certain manufacturing 

activities for licensed manufacturers. This change 

was proposed to eliminate a significant source of 

confusion among regulated industry members and 

the public as to who needs a license to manufacture 

firearms. See Broughman v. Carver, 624 F.3d 670 

(4th Cir. 2010) (distinguishing dealer-gunsmiths 

from manufacturers). 

D. Definitions of ‘‘Complete Weapon’’ 

and ‘‘Complete Muffler or Silencer 

Device’’ 

The Department proposed to add the 

terms ‘‘complete weapon’’ and 

‘‘complete muffler or silencer device’’ to 

27 CFR 478.11 and 479.11. The 

proposed definition of a ‘‘complete 

weapon’’ was a firearm, whether or not 

assembled or operable, containing all 

component parts necessary to function 

as designed but not a firearm muffler or 

silencer device. 86 FR at 27730. The 

proposed definition of a ‘‘complete 

muffler or silencer device’’ was a 

firearm muffler or firearm silencer, 

whether or not assembled or operable, 

containing all of the component parts 

necessary to function as designed. Id. 

These terms were proposed to explain 

when a frame or receiver of a firearm, 

including a firearm muffler or silencer, 

as the case may be, must be marked for 

identification. 

E. Definition of ‘‘Privately Made 

Firearm’’ 

The NPRM proposed adding the term 

‘‘privately made firearm’’ to 27 CFR 

478.11 and to define it as a firearm, 

including a frame or receiver, assembled 

by a person other than a licensed 

manufacturer, and not containing a 

serial number or other identifying 

marking placed by a licensed 

manufacturer at the time the firearm 

was produced. See 86 FR at 27730. The 

term would not include a firearm 

identified and registered in the NFRTR 

pursuant to 26 U.S.C., chapter 53, or any 

firearm made before October 22, 1968 

(unless remanufactured after that 

date).51

F. Definition of ‘‘Importer’s or 

Manufacturer’s Serial Number’’ 

The Department proposed to add the 

term ‘‘importer’s or manufacturer’s 

serial number’’ in 27 CFR 478.11 and to 

define it as the identification number, 

licensee name, licensee city or State, or 

license number placed by a licensee on 

a firearm frame or receiver or on a PMF. 

The NPRM explained that a serial 

number incorporating the abbreviated 

FFL number (also known in industry as 

the ‘‘RDS key’’) placed by a licensee on 

a PMF under the proposed rule met the 

definition of the ‘‘importer’s or 

manufacturer’s serial number.’’ The 

Department also explained that the 

proposed definition would help ensure 

that the serial numbers and other 

markings necessary to ensure tracing are 

considered the ‘‘importer’s or 

manufacturer’s serial number’’ protected 

by 18 U.S.C. 922(k) and numerous State 

laws, which prohibit possession of 

firearms with serial numbers that have 

been removed, obliterated, or altered. 

See 86 FR at 27730 n.62. 

G. Definition of ‘‘Gunsmith’’ 52

The Department proposed to amend 

the definition of ‘‘engaged in the 

business’’ as it applies to a ‘‘gunsmith’’ 

in 27 CFR 478.11 to clarify that 

businesses may be licensed as dealergunsmiths rather than as manufacturers 

if they routinely repair or customize 

existing firearms, make or fit special 

barrels, stocks, or trigger mechanisms, 

or mark firearms as a service performed 

on firearms not for sale or distribution 

by a licensee.53 The proposed 

amendment was also for the purpose of 

providing greater access to professional 

marking services so that persons who 

engage in the business of identifying 

firearms for nonlicensees may become 

licensed as dealer-gunsmiths solely to 

provide professional PMF marking 

services. 

H. Marking Requirements for Firearms 

1. Information Required to be Marked 

on the ‘‘Frame or Receiver’’ 

To properly implement the new 

definitions, the Department proposed to 

amend 27 CFR 478.92(a) and 479.102 to 

explain how and when markings must 

be applied on each part defined as a 

frame or receiver, particularly since 

there could have been more than one 

part of a complete weapon, or complete 

muffler or silencer device, which is the 

frame or receiver (i.e., when ATF has 

not identified specific part(s) as the 

frame or receiver). Under the NPRM, 

each frame or receiver of a new firearm 

design or configuration manufactured or 

imported after the publication of the 

final rule was proposed to be marked 

with a serial number, and either: (a) The 

manufacturer’s or importer’s name (or 

recognized abbreviation), and city and 

State (or recognized abbreviation) where 

the manufacturer or importer maintains 

their place of business, or in the case of 

a maker of an NFA firearm, where the 

firearm was made; or (b) the 

manufacturer’s or importer’s name (or 

recognized abbreviation), and the serial 

number beginning with the licensee’s 

abbreviated FFL number as a prefix, 

which is the first three and last five 

digits, followed by a hyphen, and then 

followed by a number (which may 

incorporate letters and a hyphen) as a 

suffix, e.g., ‘‘12345678-[number].’’ The 

serial number (with or without the FFL 

prefix) identified on each part of a 

weapon defined as a frame or receiver 

was proposed to be the same number, 

but could not duplicate any serial 

number(s) placed by the licensee on any 

other firearm. 

The NPRM proposed that licensed 

manufacturers and importers could 

continue to identify the additional 

information on firearms (other than 

PMFs) of the same design and 

configuration as they existed before the 

effective date of the final rule under the 

prior content rules, and any rules 

necessary to ensure such identification 

would have remained effective for that 

purpose. This proposed provision was 

intended to make the transition easier 

and reduce production costs incurred by 

licensees. 

Except for silencer parts transferred 

by manufacturers to other qualified 

manufacturers and dealers for 

completion or repair of devices, no 

change was proposed to the existing 

requirement that each part defined as a 

machinegun or silencer that is disposed 

of separately and not part of a complete 

weapon or device be marked with all 

required information, because 

individual machinegun conversion and 

silencer parts are ‘‘firearms’’ under the 

NFA that must be registered in the 

NFRTR. 26 U.S.C. 5841(a)(1), 5845(a), 

(b). However, for frames and receivers, 

and individual machinegun conversion 

or silencer parts defined as ‘‘firearms’’ 

that are disposed of separately, the 

proposed rule allowed the model 

designation and caliber or gauge to be 

omitted if it is unknown at the time the 

part is identified. See 86 FR at 27731. 

2. Size and Depth of Markings 

The Department did not propose 

changes to the existing requirements for 

size and depth of markings in 27 CFR 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24665 

54Under this rule, licensed collectors would only 

need to mark PMFs they receive that are defined as 

‘‘curios or relics.’’ See 27 CFR 478.11 (definitions 

of ‘‘firearm’’ and ‘‘curios or relics’’). 55Handguns that are 3D-printed are also subject 

to the registration and taxation requirements of the 

NFA if they have a smooth bore and are capable of 

being concealed on the person, thereby falling 

within the definition of ‘‘any other weapon’’ under 

the NFA. See 26 U.S.C. 5845(e). 56Under Federal law, for example, certain firearm 

transactions must be conducted through FFLs. See 

18 U.S.C. 922(a)(5) (prohibiting any person other 

than a licensee, subject to certain limited 

exceptions, from selling or delivering a firearm to 

an unlicensed out-of-state resident). 

478.92(a)(1) and 479.102(a), but for sake 

of clarity, proposed to consolidate them 

into a standalone paragraph. 

3. Period of Time To Identify Firearms 

The Department proposed to identify 

the point at which manufacturers would 

be required to place markings on 

firearms. The NPRM proposed that 

complete weapons or complete muffler 

or silencer devices, as defined in the 

rule, would be allowed to be marked up 

to seven days from completion of the 

active manufacturing process for the 

weapon or device, or prior to 

disposition, whichever is sooner. Except 

for silencer parts produced by qualified 

manufacturers for transfer to other 

licensees to complete or repair silencer 

devices, parts defined as a frame or 

receiver, machinegun, or firearm muffler 

or firearm silencer that are not 

component parts of a complete weapon 

or device when disposed of would be 

allowed to be marked up to seven days 

following the date of completion of the 

active manufacturing process for the 

part, or prior to disposition, whichever 

is sooner. Adding this proposed 

language would codify ATF Ruling 

2012–1, which explained that, whether 

the end product is to become a complete 

weapon or device, or a frame or receiver 

to be disposed of separately, it is 

reasonable for a licensed manufacturer 

to have seven days following the date of 

completion of the entire manufacturing 

process in which to mark a firearm 

manufactured and record its identifying 

information in the manufacturer’s 

permanent records. 

4. Marking of ‘‘Privately Made 

Firearms’’ 

The Department proposed to amend 

27 CFR 478.92 to require FFLs to mark, 

or supervise the marking of, the same 

serial number on each part of the 

weapon defined as frame or receiver (as 

defined in the rule) of a PMF that the 

licensee acquired, but not duplicate any 

serial number(s) placed on any other 

firearm. The marking would begin with 

the FFL’s abbreviated license number 

(first three and last five digits) as a 

prefix, followed by a hyphen, and then 

followed by a number as a suffix (e.g., 

‘‘12345678-[number]’’). Unless 

previously identified by another 

licensee, PMFs acquired by licensees on 

or after the effective date of the rule 

were proposed to be marked in this 

manner within seven days of receipt or 

other acquisition (including from a 

personal collection), or before the date 

of disposition (including to a personal 

collection), whichever is sooner.54 For 

PMFs acquired by licensees before the 

effective date of the rule, the proposed 

rule would require licensees to mark or 

cause them to be marked by another 

licensee either within 60 days from the 

effective date of a final rule, or before 

the date of final disposition (including 

to a personal collection), whichever is 

sooner.55

Consistent with the language and 

purpose of the GCA, the NPRM 

explained that this proposed provision 

was necessary to allow ATF to trace all 

firearms acquired and disposed of by 

licensees, prevent illicit firearms 

trafficking, and provide procedures for 

FFLs and the public to follow with 

respect to PMF transactions with the 

licensed community. The proposed rule 

further noted that this provision was 

crucial in light of advances in 

technology that allow unlicensed, 

including prohibited, persons easily and 

repeatedly to produce firearms at home 

from parts ordered online, or by using 

3D printers or personally owned or 

leased equipment. Such privately made 

firearms have made and will continue to 

make their way to the primary market in 

firearms through the licensed 

community.56

At the same time, nothing in the 

proposed rule restricted persons who 

are not otherwise prohibited from 

possessing firearms from making their 

own firearms without markings solely 

for personal use, nor did the proposed 

rule require individuals to mark PMFs 

when they occasionally acquire them for 

a personal collection, or sell or transfer 

them from a personal collection to 

unlicensed in-State residents in 

accordance with Federal, State, and 

local law. Further, the NPRM would not 

require FFLs to accept any PMFs, or to 

mark PMFs themselves, or to provide 

services to place identification marks on 

PMFs. Licensees would be able to 

arrange for individuals who wish to 

transfer PMFs to licensees to have them 

marked by another licensee before 

accepting them, provided they are 

properly marked in accordance with the 

proposed rule. 

5. Meaning of Marking Terms 

An additional amendment to 27 CFR 

478.92 and 478.102 was proposed to 

clarify the meaning of the terms 

‘‘legible’’ and ‘‘legibly’’ to ensure that 

‘‘the identification markings use 

exclusively Roman letters (e.g., A, a, B, 

b, C, c) and Arabic numerals (e.g., 1, 2, 

3), or solely Arabic numerals, and may 

include a hyphen,’’ and that the terms 

‘‘conspicuous’’ and ‘‘conspicuously’’ are 

understood to mean that the 

identification markings are capable of 

being easily seen and unobstructed by 

other markings when the firearm is 

assembled. 86 FR at 27733. These would 

clarify the meaning of those terms as 

explained in ATF Ruling 2002–6 

(‘‘legible’’), and ATF’s final rule at 66 

FR 40599 (Aug. 3, 2001) (referencing 

U.S. Customs Service regulations on the 

definition of ‘‘conspicuous’’). 

6. Alternate Means or Period of 

Identification 

The proposed rule would not alter the 

Director’s existing ability to authorize 

other means of identification, or a 

‘‘marking variance,’’ for any part 

defined as a firearm (including a 

machinegun or a silencer), or the 

process for such a variance. 

7. Destructive Device Period of 

Identification 

The proposed rule specified a sevenday grace period in which to mark all 

completed firearms, including 

destructive devices (similar to other 

firearms), and would have allowed ATF 

to grant a variance from this period. 

There were no proposed changes to the 

marking requirements for destructive 

devices. 

8. Adoption of Identifying Markings 

The Department proposed allowing 

licensed manufacturers and importers to 

adopt an existing serial number, caliber/ 

gauge, model, or other markings already 

identified on a firearm, provided that 

they legibly and conspicuously place, or 

cause to be placed, on each part (or 

part(s)) defined as a frame or receiver, 

either the FFL’s name (or recognized 

abbreviation), and city and State (or 

recognized abbreviation) where they 

maintain their place of business; or their 

name (or recognized abbreviation) and 

their abbreviated FFL number, as 

described in Section III.H.1 of this 

preamble, followed by the existing serial 

number (including any other 

abbreviated FFL prefix) as a suffix, e.g., 

‘‘12345678-[serial number],’’ to ensure 

the traceability of the firearm. This 

language was proposed to supersede 

ATF Ruling 2013–3 as it applied to 

licensed manufacturers and importers. 


jspears on DSK121TN23PROD with RULES2
24666 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

57The definition of ‘‘transfer’’ in the NFA only 

includes ‘‘selling, assigning, pledging, leasing, 

loaning, giving away, or otherwise disposing of’’ a 

firearm. 26 U.S.C. 5845(j); see also United States v. 

Smith, 642 F.2d 1179, 1182 (9th Cir. 1981) (‘‘We 

cannot agree that Congress intended to impose a 

transfer tax and require registration whenever mere 

physical possession of a firearm is surrendered for 

a brief period.’’). 

58These changes are consistent with ATF 

enforcement policy. See NFA Handbook, ATF EPublication 5320.8, sec. 7.4.6, p.46, sec. 9.5.1, p. 60 

(revised April 2009). With regard to silencer repairs, 

in order to avoid any appearance that an unlawful 

‘‘transfer’’ has taken place, ATF recommends that 

an Application for Tax Exempt Transfer and 

Registration of Firearm, ATF Form 5, be submitted 

for approval prior to conveying the firearm for 

repair or identifying the firearm. The conveyance 

may also be accomplished by submission of a letter 

from the registrant to the qualified FFL advising the 

FFL that the registrant is shipping or delivering the 

firearm for repair/identification and describing the 

repair or identification. Return of the registered 

silencer to the registrant may likewise be 

accomplished by submission of an ATF Form 5 or 

by a letter from the FFL to the registrant that 

accompanies the silencer. 

59See FFL Newsletter, May 2012, at 5 (‘‘If a 

firearm is marked with two manufacturer’s names, 

or multiple manufacturer and importer names, FFLs 

should record each manufacturers’ and importers’ 

[sic] name in the A&D record.’’). 

60This is consistent with prior ATF guidance to 

the firearms industry. See FFL Newsletter, Sept. 

2011, at 5. 

The proposal was aimed at avoiding 

multiple markings on firearms that 

could be confusing to law enforcement 

and alleviate concerns of some 

manufacturers and importers regarding 

serial number duplication when 

firearms are remanufactured or 

imported. 

9. Firearm Muffler or Silencer Parts 

Transferred Between Qualified 

Licensees 

Licensed and qualified firearm 

muffler or silencer manufacturers 

routinely transfer small internal muffler 

or silencer components to each other to 

produce complete devices. Licensees 

qualified under the NFA routinely do 

the same when repairing existing 

devices. Because of the difficulties and 

expense of marking and registering 

small individual components used to 

commercially manufacture a complete 

muffler or silencer device with little 

public safety benefit, the NPRM 

proposed to allow qualified 

manufacturers to transfer parts defined 

as a firearm muffler or silencer to other 

qualified manufacturers without 

immediately identifying or registering 

them. Once the new device was 

completed with the part, the 

manufacturer would be required to 

identify and register the device in the 

manner and within the period specified 

in the proposed rule for a complete 

device. Likewise, the NPRM proposed to 

allow qualified manufacturers to 

transfer muffler or silencer replacement 

parts to qualified manufacturers and 

dealers to repair existing devices 

already identified and registered in the 

NFRTR. Further, the rule proposed to 

amend the definition of ‘‘transfer’’ to 

clarify that temporary conveyance of a 

lawfully possessed NFA firearm, 

including a silencer, to a qualified 

manufacturer or dealer for the sole 

purpose of repair, identification, 

evaluation, research, testing, or 

calibration, and return to the same 

lawful possessor is not a ‘‘transfer’’ 

requiring additional identification or 

registration in the NFRTR.57 The 

proposed changes were intended to 

reduce the practical and administrative 

problems of marking and registering 

silencer parts by the regulated industry, 

and to avoid a potential resource burden 

on ATF to process numerous tax-exempt 

registration applications with little 

public safety benefit.58

10. Voluntary Classification of Firearms 

and Armor Piercing Ammunition 

As described in the NPRM, for many 

years, ATF has acted on voluntary 

requests from persons, particularly 

manufacturers who are developing new 

products, by issuing determinations or 

‘‘classifications’’ on whether an item is 

a ‘‘firearm’’ or ‘‘armor piercing 

ammunition’’ as defined in the GCA or 

NFA. The Department proposed to 

clarify the existing process by which 

persons may voluntarily submit such 

requests to ATF. The NPRM proposed 

that requests be submitted in writing, or 

on an ATF form, executed under the 

penalties of perjury with a complete and 

accurate description of the item, the 

name and address of the manufacturer 

or importer thereof, and a sample of 

such item for examination along with 

any instructions, guides, templates, jigs, 

equipment, tools, or marketing materials 

that are made available to the purchaser 

or recipient of the item. Upon 

completion of the examination, ATF 

would return the sample to the person 

who made the request unless a 

determination was made that return of 

the sample would be, or place the 

person, in violation of law. The NPRM 

also proposed to codify ATF’s policy of 

not evaluating a firearm accessory or 

attachment ‘‘unless it is installed on the 

firearm(s) in the configuration for which 

it is designed and intended to be used,’’ 

and further explained that the Director’s 

determination would not be applicable 

to or authoritative with respect to any 

other sample, design, model, or 

configuration. 86 FR at 27734. 

I. Recordkeeping 

1. Acquisition and Disposition Records 

The Department proposed minor 

amendments to 27 CFR 478.122, 

478.123, 478.125, and 478.125a, 

pertaining to the acquisition and 

disposition records maintained by 

importers, manufacturers, and dealers. 

Due to the possibility that a firearm may 

have more than one frame or receiver as 

defined in the proposed rule, and the 

changes to marking regulations, the rule 

proposed to make certain words plural, 

(e.g., manufacturer(s), importer(s), and 

serial number(s)) in the recordkeeping 

regulations for the formatting of FFL 

records, as applicable. These proposed 

changes were considered necessary to 

ensure that FFLs record more than one 

manufacturer, importer, or serial 

number, if applicable, when acquiring 

or disposing of firearms with multiple 

components marked as the frame or 

receiver, or firearms that have been 

remanufactured or reimported by 

another licensee. This is consistent with 

prior ATF guidance to the firearms 

industry.59

The rule also proposed to amend 27 

CFR 478.122 and 478.123 to require 

licensed importers and manufacturers to 

consolidate their records of importation, 

manufacture, or other acquisition, and 

their sale or other disposition in a 

format containing the applicable 

columns specified in a table under the 

regulation. These changes were 

proposed to supersede ATF Rulings 

2011–1 and 2016–3. 

The NPRM proposed to make minor 

clarifying changes to the format of the 

column titles required on the A&D 

Record in § 478.125(e). The proposed 

change was to make clear that both the 

name and license number (not the 

address) of a licensee from whom 

firearms are received and to whom they 

are disposed are recorded properly in 

the A&D Record. 

The rule also proposed minor changes 

to § 478.125(f) to make clear that in the 

event the licensee records a duplicate 

entry with the same firearm and 

acquisition information, whether to 

close out an old record book or for any 

other reason, the licensee must record a 

reference to the date and location of the 

subsequent entry (e.g., date of new 

entry, book name/number, page number, 

and line number) to document the 

disposition. The NPRM explained the 

proposed change is needed to ensure 

that acquisition records are closed out 

when firearms are no longer in 

inventory 60 and would resolve 

problems that ATF has encountered 

during the inspection process and FFLs 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24667 

61ATF previously approved electronic storage of 

certain records under the conditions set forth in 

ATF Rulings 2016–1 (Requirements to Keep 

Firearms Records Electronically) and 2016–2 

(Electronic ATF Form 4473). 

62See Retention of Firearms Transaction Records, 

50 FR 26702 (June 28, 1985). 

have encountered when responding to 

trace requests. 

2. Firearms Transaction Records 

Some technical amendments were 

proposed at 27 CFR 478.124 pertaining 

to information recorded on the Form 

4473. Like changes to the recordkeeping 

regulations, the rule proposed to make 

certain words plural on the Form 4473 

to ensure that FFLs would record more 

than one manufacturer, importer, and 

serial number, if applicable. The NPRM 

also proposed to remove from paragraph 

(f) a phrase that indicates than an FFL 

must fill out the firearm description 

information only after filling out the 

information about the transferee. The 

proposed deletion would clarify ATF 

Procedure 2020–1, which sets forth an 

alternative method of complying with 

section 478.124(f) for non-over-thecounter firearm transactions, and reflect 

the current process for completing the 

Form 4473. 

3. Recordkeeping for ‘‘Privately Made 

Firearms’’ 

The Department proposed changes to 

the regulations regarding recordkeeping 

by licensees to account for any 

voluntary receipts or other acquisitions 

(including from a personal collection) of 

PMFs, and corresponding dispositions 

(including to a personal collection). If a 

PMF were received or otherwise 

acquired by a licensee or disposed of, or 

imported, the proposed rule required 

the abbreviation ‘‘PMF’’ to be recorded 

as the manufacturer in the appropriate 

column, as well as the PMF serial 

number beginning with the abbreviated 

FFL number in the serial number 

column. The rule proposed requiring 

licensees to first record the PMF as an 

acquisition in the licensee’s A&D 

records upon receipt from the private 

owner (whether or not the licensee kept 

the PMF overnight). Once marked, the 

licensee would update the acquisition 

entry with the identifying information 

and record its return as a disposition to 

the private owner. 

4. NFA Forms Update 

The Department proposed minor 

technical amendments to 27 CFR 

479.62, 479.84, 479.88, 479.90, and 

479.141, pertaining to the Application 

to Make, NFA Form 1 (‘‘Form 1’’), the 

Application to Transfer, NFA Form 4 

(‘‘Form 4’’), Tax Exempt Transfers— 

SOTs, NFA Form 3 (‘‘Form 3’’), Tax 

Exempt Transfers—Governmental 

Entities, NFA Form 5 (‘‘Form 5’’), and 

the Stolen or Lost Firearms Report, 

Form 3310.11 (‘‘Form 3310.11’’), 

respectively. The technical amendments 

were proposed to make certain words on 

the forms plural (i.e., manufacturer(s), 

importer(s), serial number(s)). 

5. Importation Forms Update 

The Department proposed minor 

technical amendments to 27 CFR 

447.42, 447.45, 478.112, 478.113, 

478.114, and 479.112, pertaining to the 

importation of firearms. Like the other 

recordkeeping changes, these technical 

amendments were proposed to ensure 

that more than one name, manufacturer, 

country, importer, or serial number, if 

applicable, would be recorded when 

completing importation forms. 

J. Record Retention 

Given advancements in electronic 

scanning and storage technology, ATF’s 

acceptance of electronic recordkeeping, 

the reduced costs of storing firearm 

transaction records, the increased 

durability and longevity of firearms, and 

the public safety benefits of ensuring 

that records of active licensees are 

available for tracing purposes, the 

Department proposed to amend 27 CFR 

478.129 to require FFLs to retain all 

records until business or licensed 

activity is discontinued, either on paper 

or in an electronic format approved by 

the Director,61 at the business or 

collection premises readily accessible 

for inspection. Also, a proposed 

amendment to 27 CFR 478.50(a) would 

allow all FFLs, including manufacturers 

and importers, to store paper records 

and forms older than 20 years at a 

separate warehouse, which would be 

considered part of the business premises 

for this purpose and subject to 

inspection. These amendments would 

reverse a 1985 rulemaking allowing 

non-manufacturer/importer FFLs to 

destroy their records after 20 years.62

IV. Analysis of Comments and 

Department Responses for the Proposed 

Rule 

In response to the NPRM, ATF 

received 290,031 comments. 

Submissions came from individuals, 

including foreign nationals, lawyers, 

government officials, and various 

interest groups. Of the comments 

reviewed, there were nearly 114,400 

comments that expressed support for 

the proposed rule. Of these, over 68,000 

were submitted by individuals as form 

letters, i.e., identical text that is often 

supplied by organizations or found 

online and recommended to be 

submitted to the agency as a comment. 

There were nearly 170,550 comments 

opposed to the rule, of which over 

88,000 comments were submitted as 

form letters. For over 1,500 comments, 

the commenters’ positions could not be 

determined. The commenters’ grounds 

for support and opposition, along with 

specific concerns and suggestions, are 

discussed below. 

A. Issues Raised in Support of the Rule 

Thousands of commenters broadly 

expressed support for the NPRM. Over 

3,000 comments simply expressed 

support, stating ‘‘stop ghost guns,’’ but 

numerous other comments focused on 

the need to regulate ‘‘ghost guns’’ and 

were supportive of the proposed change 

to treat items like weapon parts kits the 

same as other firearms because the 

commenters believed such treatment is 

necessary for public safety. These 

commenters pointed to the rise and 

proliferation of ‘‘do-it-yourself’’ (‘‘DIY’’) 

firearms used in crimes and argued that 

it is easy for extremists, violent 

criminals, and traffickers, among others, 

to skirt the law and obtain untraceable 

guns without undergoing a background 

check. They stated that the rule was 

necessary to combat the emerging threat 

that ‘‘ghost guns’’ pose to public safety. 

As discussed below, numerous other 

commenters ranging from lawmakers to 

prosecutors to religious, medical, and 

social policy-oriented organizations all 

raised various points as to why they 

were supportive of the Department’s 

proposed amendments to ATF 

regulations. Some commenters in 

support of the rule also provided 

suggestions on where they believed the 

regulatory text could be enhanced or 

further clarified. 

1. Changes are Consistent With Law 

Comments Received 

Commenters in support remarked that 

the proposed definitions are justified 

given the ease with which prohibited 

persons can intentionally circumvent 

Federal regulations to acquire 

unfinished frames or receivers that can 

be easily converted to functional 

firearms without a background check. 

Commenters agreed that ATF’s 

proposed definitions are consistent with 

Congress’s intent to regulate the core 

component of the firearm and that the 

plain meaning of ‘‘firearm’’ in the GCA 

includes any kits or nearly complete 

frames or receivers that can be readily 

converted into a firearm. One 

commenter noted the case United States 

v. Drasen, 845 F.2d 731, 736–37 (7th 

Cir. 1988), where the Seventh Circuit 

rejected the argument that a collection 


jspears on DSK121TN23PROD with RULES2
24668 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

of rifle parts cannot be a ‘‘weapon.’’ 

Other commenters agreed that ATF’s 

proposed rule would be a functional 

definition that preserves existing 

designs while defining the frame or 

receiver to include those with split or 

multi-piece frame or receiver 

configurations, and allows for flexibility 

over time to account for new 

technologies. They stated that this 

flexible approach, including 

manufacturers’ ability to submit a 

firearm to ATF and receive a 

classification on which component 

constitutes the receiver, would preserve 

the existing designations that ATF has 

made and minimize the burden on the 

gun industry. 

Similarly, others agreed that the 

definition and factors set forth for the 

term ‘‘readily’’ are consistent with case 

law interpreting the term, and that the 

proposed definition and such case law 

provides manufacturers with fair 

warning on how the factors will be 

considered. Further, some commenters 

indicated that the proposed ‘‘readily’’ 

test is consistent with ATF’s past 

approach to reviewing unfinished 

receivers. Some commenters, such as 

the Brady Group, the District Attorney 

and County Counsel for the County of 

Santa Clara, and the Attorney General 

for the State of California stated that for 

a few decades, ATF had issued 

classification letters taking the position 

that some unfinished receivers, which 

are identical to the so-called ‘‘80% 

receivers’’ on the market today, were 

‘‘firearms’’ under the GCA. They stated 

that, in that time period, ATF’s analysis 

was based on an approach that 

examined how quickly and easily an 

unfinished receiver or frame could be 

turned into a fully functional firearm— 

that is, whether it could ‘‘readily be 

converted’’ to function as the firearm it 

was specifically designed to be. The 

same commenters then asserted that, 

from around 2006 to the present, ATF 

changed its analysis and began to look 

at which machining operations still 

needed to be performed to determine 

whether a partially completed receiver 

or frame is a ‘‘firearm’’ under the GCA. 

Commenters believed that ATF’s change 

in interpretation led to an increase in 

the number of PMFs that have 

proliferated and that are being recovered 

in crime scenes. 

Department Response 

The Department acknowledges the 

commenters’ support for the proposed 

rule. The definitions in the proposed 

rule are consistent with the plain 

meaning of the term ‘‘firearm’’ in the 

GCA as it includes frames or receivers 

of weapons that are designed to or may 

readily be converted to fire, not merely 

of weapons that are in a functional state 

that will expel a projectile. The 

Department agrees with commenters 

that any new definitions must be 

general enough to account for changes 

in technology and terminology while 

preserving ATF’s past classifications to 

minimize the impact on the firearms 

industry. The Department further agrees 

that the proposed definition of the term 

‘‘readily’’ is consistent with case law 

that provides manufacturers with fair 

warning on how the factors in that 

definition are evaluated. 

The Department also agrees that ATF 

took the position in past classification 

letters that some unfinished receivers 

were firearms because of the ease with 

which they can be made functional. 

However, ATF disagrees with 

commenters who stated that ATF 

changed its position from 2006 to the 

present concerning partially complete 

frames or receivers when it determined 

that specific machining operations had 

to be performed with respect to certain 

partially complete frames or receivers. 

Rather than a new or different test, how 

quickly and easily an item could be 

made functional is largely determined 

by which machining operations still 

needed to be performed. ATF has 

maintained and continues to maintain 

that a partially complete frame or 

receiver alone is not a frame or receiver 

if it still requires performance of certain 

machining operations (e.g., milling out 

the fire control cavity of an AR–15 billet 

or blank, or indexing for that operation) 

because it may not readily be completed 

to house or hold the applicable fire 

control components. When a frame or 

receiver billet or blank is indexed or 

‘‘dimpled,’’ it indicates the location for 

drilling or milling the holes or cavities 

necessary to install the fire control 

components necessary to initiate, 

complete, or continue the firing cycle. 

However, this rule recognizes that the 

aggregation of a template or jig with a 

partially complete frame or receiver can 

serve the same purpose as indexing, 

making an item that is clearly 

identifiable as a partially complete 

frame or receiver into a functional one 

efficiently, quickly, and easily (i.e., 

‘‘readily’’). Prior to this rule, ATF did 

not examine templates, jigs, or other 

items and materials in determining 

whether partially complete frames or 

receivers were ‘‘firearms’’ under the 

GCA. For this reason, ATF issued some 

classifications concluding that certain 

partially complete frames or receivers 

were not ‘‘frames or receivers’’ as 

defined in this rule. Thus, any 

classification requests for partially 

complete, disassembled, or 

nonfunctional items or parts kits that 

were previously submitted to ATF, 

particularly those submitted without 

their associated templates, jigs, molds, 

instructions, equipment, or marketing 

materials as required by this rule, must 

be re-evaluated consistent with this rule 

to determine whether they would now 

be classified as ‘‘firearms,’’ ‘‘frames,’’ or 

‘‘receivers.’’ 

2. Enhances Public Safety 

Comments Received 

Commenters supporting the proposed 

rule argued that the proposed rule is 

needed to make communities safer 

because under-regulation has made the 

rise of so-called ghost guns the fastestgrowing public safety threat in the 

country. Some commenters emphasized 

that women who are victims of domestic 

abuse are severely affected by the rapid 

proliferation of unserialized firearms 

that can be easily acquired without a 

background check by convicted 

domestic violence offenders or those 

subject to a domestic violence 

restraining order. Healthcare and 

physicians’ organizations, which have 

called gun violence a public health 

epidemic, urged issuance of the 

proposed rule as a necessary step to 

reduce or prevent firearm-related 

injuries and death. 

Various commenters, including 

Members of Congress, State lawmakers, 

and State and local prosecutors noted 

the uptick in the involvement of ‘‘ghost 

guns’’ in crimes and provided numbers 

demonstrating the rise of unserialized 

firearms recovered or used in crimes in 

their jurisdictions. For example, a 

comment from several State Attorneys 

General asserted that the Philadelphia 

Police Department recovered 287 

unserialized guns in the first half of 

2021, whereas in 2019, the Philadelphia 

police recovered just 95 unserialized 

guns, and that unserialized guns 

represented 2.23 percent of all guns 

recovered after gun crimes. Similarly, a 

comment from the Gun Violence Task 

Force of the New York County Lawyers 

Association asserted that in 2020, law 

enforcement in New York recovered 220 

‘‘ghost guns’’ compared to 72 in 2019, 

and 38 in 2018. They stated that this 

represented a 479 percent increase over 

a three-year period. One group asserted 

that law enforcement officers across the 

country are increasingly identifying 

trafficking rings that mass produce and 

sell untraceable firearms. These 

commenters stated that it is important to 

take proactive steps now, given that 

technology continues to rapidly evolve 

and makes it likely that these weapons 

will become easier and cheaper to 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24669 

63See Public Law 90–351, sec. 901(a)(1), 82 Stat. 

225. 

manufacture privately, especially for 

criminals intending to skirt the law. 

Department Response 

The Department acknowledges that 

the rule will enhance public safety by 

helping to ensure that more firearms 

may be traced by law enforcement to 

solve crime and arrest the perpetrators. 

As discussed in Section II.B of this 

preamble, ATF has also seen an 

exponential increase in the number of 

suspected PMFs recovered and reported 

for tracing. At the same time, by 

requiring sellers to have licenses and 

conduct background checks when 

firearm parts kits are manufactured and 

sold, the rule will help prevent 

potentially dangerous persons from 

acquiring those kits and easily making 

functional weapons. 

3. Prevents Companies From Exploiting 

Loopholes 

Comments Received 

Many commenters in support of the 

proposed rule argued that it was 

necessary to regulate so-called ghost 

guns because they believe that the 

primary reason people acquire them is 

for illicit purposes and that companies 

are exploiting existing loopholes in 

Federal regulations. Other commenters 

indicated that companies making and 

advertising DIY kits intentionally target 

prohibited purchasers or other 

dangerous parties by emphasizing the 

untraceable nature of their products. 

These companies, the commenters 

pointed out, frequently use the absence 

of a serial number and the ability to 

purchase the gun without a background 

check as selling points. Accordingly, 

these commenters argued it is evident 

that PMFs are not being used purely by 

hobbyists but are instead being made 

and sold for use on the street by violent 

criminals and gun traffickers precisely 

because their acquisition falls outside 

the scope of existing Federal 

regulations. 

Some commenters made reference to 

ATF’s Ruling 2015–1 that addressed 

inquiries from the public asking 

whether FFLs, or unlicensed machine 

shops, may engage in the business of 

completing, or assisting in the 

completion of, the manufacture of 

‘‘firearm frames or receivers’’ 

(specifically from castings or blanks) for 

unlicensed individuals without 

becoming licensed as a manufacturer. 

These commenters asserted that the 

‘‘ghost gun industry’’ ensures that its 

handgun frames and semiautomatic 

receivers do not meet ATF’s 2015 

interpretation of ‘‘frame or receiver’’ 

simply by not drilling into the frame or 

receiver, shipping the mostly finished 

item to the purchaser, and providing 

detailed instructions on how to 

complete the firearm privately, often 

within minutes. This allows the 

industry to sell thousands of weapons 

with no serial numbers or background 

checks. One commenter emphasized the 

proposed multi-factor analysis for 

‘‘readily’’ provides ATF with the 

necessary flexibility to adapt to 

innovations in firearms technology and 

likely prevents these parts kits 

manufacturers from developing 

products aimed at complying with a 

narrow construction of ATF regulations 

while skirting the spirit and intent of 

the GCA. 

Department Response 

The Department acknowledges the 

commenters’ support for the proposed 

rule. This rule interprets the plain 

language of the GCA to update its 

regulations and clarify when a license is 

required, which part of a firearm must 

be marked, and what records must be 

maintained by licensees. The rule 

clarifies that the regulatory definitions 

of ‘‘firearm’’ and ‘‘frame or receiver’’ 

include weapon and frame or receiver 

kits with partially complete frames or 

receivers, which are therefore subject to 

regulatory controls under the GCA or 

NFA. Sellers of such parts kits are 

required to be licensed, and the frames 

or receivers of those firearms must be 

marked with a serial number and other 

identifying information. ATF anticipates 

that, as technology develops, this rule 

will help to ensure that persons who 

commercially produce partially 

complete frames or receivers that can 

efficiently, quickly, and easily be 

completed are licensed and conduct 

background checks when sold to 

unlicensed individuals. This will help 

prevent prohibited persons from 

acquiring such frames and receivers. 

4. Regulates ‘‘Privately Made Firearms’’ 

Like Other Firearms 

Comments Received 

Numerous commenters stated that 

PMFs should be regulated the same as 

any other firearm to ensure that 

manufacturers of weapon parts kits are 

licensed, adhere to recordkeeping 

requirements, and perform background 

checks on the purchasers of their 

products. Many commenters, including 

lawmakers from States such as 

Maryland, Massachusetts, and New 

York, stated that although some States 

that have enacted, or are working to 

pass, legislation regulating the 

possession or making of unserialized 

firearms, these laws cannot work in a 

vacuum and that there are limits to what 

any one State can do. Less restrictive 

gun laws in neighboring States, they 

argued, undermine States with tighter 

restrictions. Unserialized firearms and 

unfinished frames and receivers will 

continue to flow into their communities. 

Federal regulation, they argued, is 

therefore needed to close the loophole; 

otherwise, law enforcement and State 

efforts to prevent gun violence and 

enforce their own laws will be severely 

undermined. For example, the County 

of Santa Clara District Attorney wrote 

that the lack of adequate serialization 

and recordkeeping of PMFs has made it 

difficult for law enforcement to 

apprehend individuals involved in 

ongoing criminal activity or firearms 

traffickers who supply criminals with 

weapons. Similarly, another 

prosecutors’ organization stated that 

prosecutors rely on gun markings to 

generate leads and identify patterns, and 

the lack of serial numbers on PMFs 

undermines prosecutors’ ability to 

effectively investigate and prosecute 

gun crime. 

Lastly, some commenters stated that 

ATF should reject the inaccurate claims 

that the NPRM would make criminals 

out of law-abiding gun owners, stating 

that the rule would not reach or restrict 

private individuals legally allowed to 

possess a firearm who previously 

purchased nearly complete frames or 

receivers or ghost gun kits. These 

individuals, they argued, will be no 

more exposed to criminal liability than 

they are currently. They concluded that 

the NPRM will cut off the supply of 

ghost guns to traffickers and prohibited 

persons at its source and not burden 

law-abiding, good faith actors. 

Department Response 

The Department acknowledges 

commenters’ support for the proposed 

rule, and notes that one of the primary 

purposes of the GCA is to assist State 

and local jurisdictions to control the 

traffic of firearms within their own 

borders through the exercise of their 

police power.63 Under the rule as 

proposed and finalized, when licensees 

receive privately made or DIY firearms 

in the course of their licensed business 

or activity, they will need to mark or 

cause those firearms to be marked. This 

allows PMFs to be traceable by State 

and local law enforcement whenever 

they, like commercially produced 

firearms, are introduced into the 

regulated marketplace. At the same 

time, neither the GCA nor the proposed 

or final rule prohibits unlicensed 


jspears on DSK121TN23PROD with RULES2
24670 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

64See footnote 122, infra. 65The existence of a frame or receiver is not a 

precondition to classifying a weapon as a firearm 

under section 921(a)(3)(A), as section 921(a)(3) 

defines a ‘‘firearm’’ in the disjunctive with each 

subpart separated by the disjunctive participle ‘‘or.’’ 

See Black’s Law Dictionary 1095 (6th ed.1990) 

(defining the term ‘‘or’’ to mean ‘‘[a] disjunctive 

participle used to express an alternative or to give 

a choice of one among two or more things’’); 

Antonin Scalia & Bryan A. Garner, Reading Law: 

The Interpretation of Legal Texts sec. 12, at 116 

(2012) (‘‘Under the conjunctive/disjunctive canon, 

and combines items while or creates alternatives 

. . . . With a conjunctive list, all . . . things are 

required—while with the disjunctive list, at least 

one of the [things] is required, but any one . . . 

satisfies the requirement.’’). Thus, while the term 

‘‘firearm’’ in section 921(a)(3)(B) includes the frame 

or receiver of a weapon described in section 

921(a)(3)(A), section 921(a)(3)(A) does not require a 

weapon to have a ‘‘frame or receiver,’’ as each 

subpart qualifies, on its own, as a ‘‘firearm’’ for 

purposes of the GCA. Otherwise, section 

921(a)(3)(A) would be superfluous. 

individuals from marking (non-NFA) 

firearms they make for their personal 

use, or when they occasionally acquire 

them for a personal collection, or sell or 

transfer them from a personal collection 

to unlicensed in-State residents 

consistent with Federal, State, and local 

law. There are also no recordkeeping 

requirements imposed by the GCA or 

the proposed or final rule upon 

unlicensed persons who make their own 

firearms, but only upon licensees who 

choose to take PMFs into inventory. In 

sum, this rule does not impose any new 

requirements on law-abiding gun 

owners. 

5. Suggested Changes to the Text 

Some commenters in support of the 

rule offered several suggestions on the 

text of the final rule while others asked 

that ATF take certain information into 

consideration. Notably, the combined 

comment submitted by 22 State 

Attorneys General in support of the 

proposed definitions offered seven 

suggestions for the final rule. The 

commenters’ suggestions are addressed 

in the following paragraphs. 

a. Definition of ‘‘Firearm’’ and Weapon 

Parts Kits 

Comments Received 

Some commenters urged ATF to 

clarify the relationship between a 

weapon parts kit and a partially 

complete frame or receiver. Although 

the proposed rule includes a ‘‘weapon 

parts kit’’ within the definition of 

‘‘firearm’’ and separately defines a 

‘‘partially complete, disassembled, or 

inoperable frame or receiver,’’ the 

commenters stated that a partially 

complete frame is often sold as part of 

a weapon parts kit. Therefore, the 

commenters suggested that ATF clarify 

whether a parts kit must include a 

partially complete frame or receiver in 

order to satisfy the definition of 

‘‘firearm.’’ 

Other commenters asked ATF to 

consider how to effectively regulate the 

domestic distribution of Computer 

Aided Manufacturing (‘‘CAM’’) and 

Computer Aided Design (‘‘CAD’’) files 

and other software and technology used 

to produce firearms. They explained 

that these types of files are just like 

weapon parts kits and can be used to 

‘‘readily’’ assemble a working firearm. 

The commenters stated that the 

Department of Commerce currently 

regulates only the international 

distribution and export of CAM or CAD 

files for the production of firearms 

where such files are ‘‘ready for insertion 

into a computer numerically controlled 

machine tool, additive manufacturing 

equipment, or any other equipment that 

makes use of’’ the files ‘‘to produce the 

firearm frame or receiver or complete 

firearm.’’ 15 CFR 734.7(c). They 

suggested that there are opportunities 

for ATF to work alone or with other 

Departments, such as Commerce, to 

address the lack of regulation of the 

domestic distribution of CAM and CAD 

files and other software and technology 

used to produce firearms. 

Department Response 

The Department agrees with 

commenters that the NPRM supplement 

entitled ‘‘Partially Complete, 

Disassembled, or Inoperable Frame or 

Receiver’’ should make clear that it 

includes a ‘‘frame or receiver parts kit’’ 

with a partially complete, disassembled, 

or nonfunctional (replacing 

‘‘inoperable’’ in the final rule to 

describe the item more accurately) 64

frame or receiver. The final rule 

incorporates that addition. However, a 

weapon parts kit need not have a 

partially complete frame or receiver, as 

defined in this rule, to satisfy the 

definition of ‘‘firearm’’ under section 

921(a)(3)(A).65 For example, a weapon 

parts kit that contains pieces of a multipiece frame or receiver, as defined in 

this rule, may still meet the definition 

of ‘‘firearm’’ under section 921(a)(3)(A) 

if the kit ‘‘is designed to or may readily 

be completed, assembled, restored, or 

otherwise converted to expel a projectile 

by the action of an explosive.’’ 

Regarding computer files, this rule as 

proposed and finalized does not 

regulate the domestic distribution of 

CAM or CAD computer files. This rule 

implements the GCA, which does not 

regulate the information used to 

manufacture firearms. However, it 

would violate federal law to aid and 

abet (18 U.S.C. 2) or conspire (18 U.S.C. 

371) with others to manufacture 

firearms without a license (18 U.S.C. 

922(a)(1)), which could include 

someone providing specially designed 

computer instructions for machines, 

such as Computer Numeric Control 

(CNC) machines or 3D printers, knowing 

that the purchaser is engaged in the 

business of producing firearms for sale 

or distribution without a license. 

b. General Definition of ‘‘Frame or 

Receiver’’ 

Comments Received 

Some commenters in support of the 

proposed rule were concerned with the 

language ‘‘when the complete weapon is 

assembled’’ in the general definition of 

‘‘frame or receiver,’’ which was 

proposed to be defined, in part, as a 

‘‘part of a firearm that, when the 

complete weapon is assembled, is 

visible from the exterior and provides 

housing or a structure designed to hold 

one or more fire control components’’ 

(emphasis added). The commenters 

stated that the italicized language makes 

the definition susceptible to being read 

to say that the part of a weapon that is 

the ‘‘frame or receiver’’ only becomes so 

when the complete weapon is 

assembled. To avoid that possible 

misreading, the commenters suggested 

the sentence should indicate it is a part 

of a complete weapon that is visible 

from the exterior when the complete 

weapon is assembled and provides 

housing designed to hold or integrate 

one or more fire control components. 

Additionally, commenters also 

suggested the proposed definition of 

‘‘frame or receiver,’’ which refers to ‘‘[a] 

part of a firearm,’’ be changed to ‘‘[a] 

part of a complete weapon,’’ given that 

under both the GCA and regulatory 

definition, a ‘‘firearm’’ could mean just 

the ‘‘frame or receiver’’ of a weapon. 

Similarly, commenters suggested that 

‘‘complete weapon’’ also be used 

instead of ‘‘firearm’’ where ATF 

proposes to define ‘‘fire control 

component’’ as ‘‘a component necessary 

for the firearm to initiate, complete, or 

continue the firing sequence.’’ They 

suggested using ‘‘complete weapon’’ in 

other instances where the supplemental 

definition, like split or modular frame or 

receiver, uses the term ‘‘firearm’’ in the 

definition. 

Department Response 

The Department agrees that the phrase 

‘‘when the complete weapon is 

assembled, is visible’’ in the proposed 

definition of ‘‘frame or receiver’’ could 

be misinterpreted to mean that the 

weapon or device must be assembled for 

a part to be defined as a frame or 

receiver. For this reason, and because 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24671 

66Markings must also be clearly visible from the 

exterior because they may be needed to prove that 

a criminal defendant had knowledge that the serial 

number was obliterated or altered. See, e.g., Lewis 

v. United States, No. 3:12–0522, 2012 WL 5198090, 

at *4 (M.D. Tenn. Oct. 19, 2012) (serial number 

obliterated on the ‘‘visible exterior’’ of a revolver); 

State v. Shirley, No. 107449, 2019 WL 2156402, at 

*2 (Ct. App. Ohio May 16, 2019) (same); cf. United 

States v. Sands, 948 F.3d 709, 719 (6th Cir. 2020) 

(serial number is not altered or obliterated so long 

as it is ‘‘visible to the naked eye’’); United States 

v. St. Hilaire, 960 F.3d 61, 66 (2d Cir. 2020) (‘‘This 

‘naked eye test’ best comports with the ordinary 

meaning of ‘altered’; it is readily applied in the field 

and in the courtroom; it facilitates identification of 

a particular weapon; it makes more efficient the 

larger project of removing stolen guns from 

circulation; it operates against mutilation that 

impedes identification as well as mutilation that 

frustrates it; and it discourages the use of 

untraceable weapons without penalizing accidental 

damage or half-hearted efforts.’’). 

67An internal removable chassis system (as found 

in the Sig P250/320 and Beretta APX Striker) that 

houses all components of a traditional pistol frame, 

to include incorporating the slide rails and housing 

for both the trigger and sear/hammer, is a complete 

pistol frame without the polymer grip. 

the definition of ‘‘conspicuous’’ in the 

marking requirements makes clear that 

markings must be capable of being 

easily seen with the naked eye during 

normal handling of the firearm and 

unobstructed by other markings when 

the complete weapon or complete 

muffler or silencer device is assembled 

(i.e., visible),66 the phrase ‘‘when the 

complete weapon is assembled, is 

visible’’ has been removed from the 

definition of ‘‘frame or receiver’’ in the 

final rule because it is unnecessary. 

Regarding the suggestion to substitute 

‘‘complete weapon’’ for ‘‘firearm,’’ the 

Department does not believe that change 

is necessary because the final rule now 

makes clear the terms under ‘‘frame or 

receiver’’ will be defined in relation to 

the type of weapon, not to ‘‘firearms’’ 

generally. 

c. Supplement ‘‘Split or Modular Frame 

or Receiver’’ 

Comments Received 

Some commenters indicated that it 

appears an item may qualify under the 

supplement entitled ‘‘split or modular 

frame or receiver’’ only if the Director 

makes that determination based on 

certain factors. The commenters 

suggested that the definition would be 

enhanced if it also provided a standard 

that may be generally used to determine 

whether something is a ‘‘split or 

modular frame or receiver,’’ as well as 

additional factors that may inform how 

that standard is applied. In this way, the 

regulations would define ‘‘a split or 

modular frame or receiver’’ much as the 

proposed rule suggests defining 

‘‘readily.’’ The commenters 

recommended inserting ‘‘each of those 

parts shall be a frame or receiver 

unless’’ before ‘‘the Director may 

determine’’ and then changing ‘‘may 

determine’’ to ‘‘determines.’’ 

Commenters also suggested making 

clear that the courts and the public, in 

addition to the Director, may rely on the 

identified factors to determine whether 

something is a ‘‘partially complete, 

disassembled, or inoperable frame or 

receiver’’ for that definition. 

Department Response 

With respect to the definitional 

supplement ‘‘split or modular frame or 

receiver,’’ the Department disagrees that 

this provision as proposed was meant to 

be read as providing that a part may 

only qualify as a ‘‘split or modular 

frame or receiver’’ if the Director makes 

that determination based on the 

enumerated factors. This supplement 

was intended to inform the licensed 

industry and the public that if there is 

more than one part of a firearm falling 

within the proposed definition of 

‘‘frame or receiver’’ (i.e., more than one 

housing or structure for a fire control 

component), then ATF would use those 

factors when determining which 

specific part(s) of a split or modular 

weapon or device was the frame or 

receiver of that weapon or device. As 

with past ATF classifications, there 

would likely be only one such 

component specified in future designs. 

In light of these and numerous other 

comments seeking more clarity as to 

how the definition of ‘‘frame or 

receiver’’ applies with respect to split 

and modular firearms, the Department is 

adopting three subsets of the proposed 

definition of ‘‘frame or receiver’’—one 

that applies to handguns; one for rifles, 

shotguns, and projectile weapons other 

than handguns; and one for firearm 

mufflers and silencers. The Department 

agrees with numerous commenters that 

the proposed supplement to the 

definition entitled ‘‘split or modular 

frame or receiver’’ is difficult for 

persons to apply when the term ‘‘frame 

or receiver’’ was defined to include 

more than any housing for any fire 

control component. Because the final 

rule focuses on only a single component 

of a firearm based on the 

recommendations of commenters, there 

is no longer a need for a separate 

supplement entitled ‘‘split or modular 

frame or receiver’’ and it has not been 

adopted in the final rule. 

However, while defining the term 

‘‘frame or receiver’’ to focus on a single 

component and removing the 

supplement entitled ‘‘split or modular 

frame or receiver’’ provides clarity as to 

which part of a ‘‘split’’ frame or receiver 

(i.e., with upper and lower housings for 

the bolt, breechblock, and trigger 

mechanism) is regulated, it does not 

provide clarity with respect to multipiece frames or receivers that are 

designed to be disassembled into 

multiple modular subparts, more than 

one of which may house or provide a 

structure for the applicable fire control 

component specified in this rule (e.g., 

left and right halves of a frame or 

receiver). While these types of frames or 

receivers are relatively uncommon, ATF 

has seen an increase in multi-piece 

designs of frames or receivers. To 

address these new designs, the term 

‘‘multi-piece frame or receiver’’ has 

been added to the final rule to mean a 

frame or receiver that may be 

disassembled into multiple modular 

subparts. To avoid confusion between 

multi-piece receivers that may be 

disassembled into modular subparts, 

and modular handguns with an internal 

removable chassis like the Sig P250/320 

and Beretta APX Striker,67 the definition 

expressly excludes the internal frame of 

a pistol that is a complete removable 

chassis that provides housing for the 

energized component, unless the chassis 

itself may be disassembled. 

This rule clarifies for licensees which 

portion of a modular multi-piece frame 

or receiver they will need to identify 

with a serial number and additional 

identifying information. Pursuant to its 

authority under 18 U.S.C. 923(i) and 26 

U.S.C. 5842(a), ATF is prescribing in 

this rule the manner in which licensed 

manufacturers and importers (and 

makers of NFA firearms) must identify 

multi-piece frames or receivers, as 

follows: (1) The outermost housing or 

structure designed to house, hold, or 

contain either the primary energized 

component of a handgun, the breech 

blocking or sealing component of a 

projectile weapon other than a handgun, 

or the internal sound reduction 

component of a firearm muffler or 

firearm silencer, as the case may be, is 

the subpart of a multi-piece frame or 

receiver that must be marked with the 

identifying information; (2) if more than 

one modular subpart is similarly 

designed to house, hold, or contain such 

a primary component (e.g., left and right 

halves), each of those subparts must be 

identified with the same serial number 

and associated licensee information not 

duplicated on any other frame or 

receiver; and (3) the marked subpart(s) 

of a multi-piece frame or receiver must 

be presumed, absent an official 

determination by the Director or other 

reliable evidence to the contrary, to be 

part of the frame or receiver of a 

weapon. 

The final rule provides that, once a 

modular subpart of a multi-piece frame 


jspears on DSK121TN23PROD with RULES2
24672 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

68See 18 U.S.C. 927 (GCA does not preempt State 

or local law unless there is a direct and positive 

conflict with Federal law such that they cannot be 

reconciled or consistently stand together). 

69See generally Hayley Everett, Lehvoss Group 

Leads Innovate UK Project for Overprinting HighPerformance Polymers,3DPrintingIndustry.com 

(Aug. 25, 2021), available at https://

3dprintingindustry.com/news/lehvoss-group-leadsinnovate-uk-project-for-overprinting-highperformance-polymers-195071/ (last visited Mar. 

23, 2022) (‘‘Overprinting is a technique for 

designing multi-material parts when different 

materials are needed in various components of a 

part. Typically, a print is started and then paused 

midway whereby components can be embedded 

into the 3D print job. Then, the print process is 

resumed and allowed to 3D print over the 

components that have been embedded.’’); MMF #5: 

A Guide to Embedding Components in 3D Printed 

Parts, Markforged.com, available at https://

markforged.com/resources/blog/embeddingcomponents-in-3d-printed-parts (last visited Mar. 

23, 2022); How to Insert Internal Components with 

Markforged Composite 3D Printing, 

Hawkridgesys.com (June 9, 2020), available at 

https://hawkridgesys.com/blog/how-to-insertinternal-components-with-markforged-composite3d-printing (last visited Mar. 23, 2022). 

or receiver has been marked and then 

aggregated (assembled or unassembled) 

with the other frame or receiver 

subparts, the marked part cannot be 

removed and replaced unless: (1) The 

subpart replacement is not a firearm 

under 26 U.S.C. 5845; (2) the subpart 

replacement is identified by the 

licensed manufacturer of the original 

subpart with the same serial number 

and associated licensee information in 

the manner prescribed by the rule; and 

(3) the original subpart is destroyed 

under the firearm licensee’s control or 

direct supervision prior to such 

placement. These conditions are 

necessary because removing and 

replacing the identified component of a 

multi-piece frame or receiver would 

place the possessor in violation of 18 

U.S.C. 922(k) (and, if an NFA firearm, 

26 U.S.C. 5861(g) and (h)), which 

prohibits the possession of any firearm 

with the manufacturer’s or importer’s 

serial number removed. If a modular 

subpart of a multi-piece frame or 

receiver is sold separately, the rule 

requires that it be identified with an 

individual serial number. This is to 

ensure that the frame or receiver of the 

resulting weapon has traceable marks of 

identification. These clarifications with 

respect to the markings of a multi-piece 

frame or receiver are necessary for the 

final rule; otherwise, multi-piece frames 

or receivers could be sold or distributed 

piecemeal in individual subparts and 

replaced by the end user without any 

traceable marks of identification. 

Finally, to ensure that industry 

members and others can rely on ATF’s 

prior classifications, most prior ATF 

classifications and variants thereof, 

including those for externally powered 

weapons, have been grandfathered into 

the definition of ‘‘frame or receiver’’ 

along with examples and diagrams of 

those weapons, such as AR–15/M–16 

variant firearms. The only exception is 

for classifications that a partially 

complete, disassembled, or 

nonfunctional frame or receiver, 

including a parts kit, was not, or did not 

include, a firearm ‘‘frame or receiver’’ as 

defined prior to this rule. Any such 

classifications, to include weapon or 

frame or receiver parts kits, would need 

to be resubmitted for evaluation. 

Further, if persons remain unclear as to 

which specific portion of a weapon or 

device falls within the definition of 

‘‘frame or receiver,’’ then they may still 

voluntarily submit a request to ATF as 

otherwise provided in this rule. 

d. Definition of ‘‘Privately Made 

Firearm’’ 

Comments Received 

Some commenters suggested that ATF 

should explain that ‘‘made,’’ as used in 

the definition of ‘‘privately made 

firearm,’’ does not imply that firearms 

cannot be ‘‘manufactured’’ by private 

parties for purposes of other firearms 

laws. They stated that the proposed rule 

opted for ‘‘privately made firearm’’ 

instead of ‘‘privately manufactured 

firearms’’ to distinguish between what 

an FFL does (manufacture) and what a 

nonlicensee does (make). These 

commenters asserted that the NFA’s 

definition of ‘‘make’’ demonstrates that 

the distinction between ‘‘make’’ and 

‘‘manufacture’’ is not consistent 

throughout Federal law. Therefore, the 

commenters requested that ATF should 

clarify that its use of ‘‘made’’ in this 

regulation does not limit the meaning of 

either ‘‘made’’ or ‘‘manufacture’’ as used 

in this and other Federal laws and 

regulations. 

Department Response 

The Department agrees that the term 

‘‘made’’ in the definition of ‘‘privately 

made firearm’’ was not meant to restrict 

the use of the terms ‘‘made’’ or 

‘‘manufacture’’ with respect to the GCA 

or other firearms laws. As the preamble 

in the NPRM explained, the term 

‘‘made’’ was incorporated into that 

definition merely to distinguish those 

firearms that were manufactured by 

licensees from those manufactured by 

unlicensed persons. See 26 U.S.C. 

5845(i) (‘‘The term ‘make’, and the 

various derivatives of such word, shall 

include manufacturing (other than by 

one qualified to engage in such business 

under this chapter), putting together, 

altering, any combination of these, or 

otherwise producing a firearm.’’). This 

rule is not intended to limit the meaning 

of ‘‘made’’ or ‘‘manufacture’’ in the GCA 

or any other Federal law, or with respect 

to State or local firearms laws.68

e. Marking of ‘‘Privately Made 

Firearms’’ 

Comments Received 

Some supportive commenters 

suggested that the final rule should 

clarify that any identifying marks must 

be placed on the metal insert of an 

otherwise undetectable PMF, not on any 

polymer or other nonmetal part or 

component, to ensure the marks are not 

worn away during normal use. The 

commenters believed this is what the 

preamble suggested, although the text of 

the proposed regulations did not do so 

explicitly. 

The California Department of Justice 

stated that ATF should consider 

extending the PMF serialization 

requirement to owners as well as 

firearms licensees so as to foreclose the 

possibility that any PMFs will remain 

untraceable. This commenter stated that 

ATF could require owners of PMFs to 

register those weapons after a 

reasonable time frame, such as 60 days 

after the effective date of the regulation, 

which would ensure all PMFs are safely 

tracked by law enforcement. 

Department Response 

The Department agrees that the final 

rule should make clear that one of the 

acceptable methods of marking a PMF, 

or a commercially produced firearm, is 

to permanently embed a serialized metal 

plate into polymer or other nonmetal 

material. The final rule adds this as an 

acceptable example in addition to 

recognizing any other method approved 

by the Director. This can be 

accomplished by casting, molding, or 

another manufacturing method, such as 

3D overprinting.69

The Department, however, disagrees 

that serialization should be limited to a 

particular method. The current 

regulations and this rule already require 

that identification marks be placed in a 

manner not susceptible of being readily 

obliterated, altered, or removed. While 

the commenters raised the point that the 

serial number with the Federal firearms 

licensee’s abbreviated license number 

prefix would normally be placed on a 

metal insert to meet this requirement, 

the Department believes that other 

permanent methods and hardened 

materials for marking may be developed 

in the future as technology progresses. 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24673 

70See 26 U.S.C. 5842(a) (serial number ‘‘may not 

be readily removed, obliterated, or altered’’). 

71After passage of the Brady Handgun Violence 

Prevention Act in 1993 (see 18 U.S.C. 922(t)), the 

FBI promulgated regulations to implement the 

NICS. These regulations, see 28 CFR 25.7, prescribe 

the search criteria used by NICS and state: ‘‘[T]he 

following search descriptors will be required in all 

queries of the system for purposes of a background 

check: (1) Name; (2) Sex; (3) Race; (4) Complete 

date of birth; and (5) State of residence’’ (emphasis 

added). This information is needed to facilitate 

proper identification by providing additional 

information that helps match—or rule out a 

match—between an individual and a potentially 

prohibiting record. 

Additionally, the GCA, 18 U.S.C. 922(p), 

only requires that firearms be as 

detectable as the ‘‘Security Exemplar’’ 

that contains 3.7 ounces of material type 

17–4 PH stainless steel. This detectable 

material is likely to be metal, but it 

could be another substance. So long as 

the identification marks cannot readily 

be removed, obliterated, or altered, no 

additional marking requirement is 

necessary.70 However, if the serial 

number or other markings may readily 

be removed, obliterated, or altered when 

placed using a particular method or 

material, then the licensee cannot adopt 

that serialization process to meet the 

identification requirements. 

In response to the comment that the 

rule should extend the serialization 

requirement for PMFs to individual 

owners, unlike the NFA, the GCA does 

not impose a marking or recordkeeping 

requirement on unlicensed persons who 

are not engaged in a business or activity 

requiring a license. Nonetheless, under 

the GCA, 18 U.S.C. 927, State and local 

jurisdictions are free to enact their own 

requirements and restrictions on PMFs 

provided they do not directly and 

positively conflict with Federal law. 

f. Marking of a ‘‘Firearm Muffler or 

Silencer’’ 

Comments Received 

At least one commenter welcomed the 

change under which silencers would 

only need to be marked on the 

designated frame or receiver of a 

silencer, and that minor components of 

silencers would not need to be engraved 

or registered when transferred between 

Special Occupation Taxpayers (‘‘SOTs’’) 

for repair. This provision, the 

commenter stated approvingly, 

conforms policy to longstanding 

practice. 

Department Response 

The Department acknowledges 

commenters’ support for the proposal 

not to require firearm mufflers or 

silencer parts other than the frame or 

receiver of a silencer to be marked or 

registered when transferred between 

qualified SOTs for repair. This rule 

finalizes that proposal with minor 

clarifying changes. The Department 

notes that this change would not 

adversely impact public safety because 

the frame or receiver of the complete 

firearm muffler or silencer devices being 

repaired are registered in the NFRTR 

and recorded as a disposition whenever 

an actual device is transferred. 

g. Firearms Designed and Configured 

Before Effective Date of Rule 

Comments Received 

The group Everytown for Gun Safety 

Support Fund stated that ATF needs to 

make clear that its prior classifications 

of ‘‘nearly-complete’’ frames and 

receivers are no longer valid, as some 

sellers of these items display these 

classification letters on their websites to 

promote their products. The commenter 

said that this clarification was necessary 

to ensure these sellers do not continue 

to exploit outdated letters as legal cover 

for selling firearms illegally. 

Department Response 

The Department agrees with this 

comment. Certain prior ATF 

classifications of a ‘‘partially complete, 

disassembled, or nonfunctional frame or 

receiver’’ will not be grandfathered 

upon issuance of this final rule. In the 

past, ATF encountered situations in 

which incomplete frames or receivers 

were sent to ATF for classification 

without any of the other parts, jigs, 

templates, or materials that are sold or 

distributed with the item or kit. ATF 

then issued a classification that an 

unfinished item or kit was not a ‘‘frame 

or receiver’’ without the benefit of, or 

considering, such parts, jigs, templates, 

or information. In addition to not 

grandfathering these particular 

classifications, this rule finalizes the 

proposed process that any person 

seeking a voluntary classification must 

submit any associated templates, jigs, 

molds, equipment, or tools that are 

made available by the seller or 

distributor of the item or kit, to the 

purchaser or recipient of the item or kit, 

and any instructions, guides, or 

marketing materials if they will be made 

available by the seller or distributor 

with the item or kit. This is to ensure 

that a proper classification can be made 

under the new definitions. ATF will 

reconsider those firearm classifications, 

and any prior classifications of such 

items or parts kits would need to be 

resubmitted if a requester wants a 

voluntary determination. 

h. Recordkeeping Requirements 

Comments Received 

The City of Oakland, California, 

which expressed support for the 

proposed rule, stated that their support 

is based on the NPRM taking into 

account the racially inequitable impacts 

of gun violence and over-policing. The 

City had several suggestions for the final 

rule to better account for the potential 

racial collateral consequences of the 

proposed rule and help Black and 

Brown communities disproportionately 

harmed by gun violence to respond to 

PMFs already in their community. 

These suggestions included the 

following: (1) ATF should collect, 

retain, and study the information 

collected through the ATF Form 4473, 

which they stated should include 

demographic information; (2) ATF 

should provide clear guidance for local 

law enforcement on how to collect data 

on ‘‘ghost guns,’’ including data that can 

be disaggregated by race, and ensure 

that implementing the rule does not 

lead to over-policing of Black and 

Brown communities; (3) ATF should 

work with the Executive Office for U.S. 

Attorneys and other Department 

partners on how to ensure that Black 

and Brown persons are not 

disproportionately charged with 

firearms-related offenses in Federal 

prosecutions; (4) ATF should include an 

explicit non-discrimination clause with 

respect to enforcement of the rule; (5) 

ATF should include model programs 

and best practices for how communities 

can respond to and mitigate the harm 

posed by ghost guns and gun violence, 

like Oakland Ceasefire; and (6) ATF 

should develop guidance for 

manufacturers and sellers to inform 

them of ATF’s enforcement priorities. 

Department Response 

The Department acknowledges the 

commenter’s support for the proposed 

rule; however, ATF cannot ‘‘collect, 

retain, and study’’ information on the 

ATF Forms 4473 for the purpose of 

evaluating potential racial collateral 

consequences of this rule. First, ATF 

does not retain the ATF Forms 4473, as 

they are owned and maintained by FFLs 

while they are in business. Therefore, 

the demographic and other information 

included on those forms is located 

throughout the country in the 

individual business records of FFLs. 

Second, the demographic information 

on that form (race and ethnicity) may 

only be used for limited purposes— 

collecting information required for the 

FFL to run a National Instant Criminal 

Background Check System (‘‘NICS’’) 

background check,71 and for certain law 

enforcement purposes, such as correctly 


jspears on DSK121TN23PROD with RULES2
24674 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

72There are some limited circumstances under 

which the ATF Forms 4473 or information 

contained thereon is reported to ATF, for example, 

as part of the statutorily authorized demand letter 

program, pursuant to 18 U.S.C. 923(g)(5). Those 

circumstances are exceptions to the general rule, 

and even under those circumstances, ATF does not 

aggregate or centralize the demographic information 

contained on those forms. 

73Public Law 112–55, sec. 511, 125 Stat. 632 

(2011); 28 CFR 25.9. 

74See 18 U.S.C. 926 (‘‘No rule or regulation . . . 

may require that records required to be maintained 

under this chapter or any portion of the contents 

of such records, be recorded at or transferred to a 

facility owned, managed, or controlled by the 

United States or any State or any political 

subdivision thereof, nor any system of registration 

of firearms, firearms owners, or firearms 

transactions or dispositions be established.’’); 

Public Law 103–159, sec. 103(i), 107 Stat. 1536 

(1993) (‘‘No department, agency, officer, or 

employee of the United States may—(1) require that 

any record or portion thereof generated by the 

[NICS] system established under this section be 

recorded at or transferred to a facility owned, 

managed, or controlled by the United States or any 

State or political subdivision thereof . . . .’’). 

Additionally, since 1979, congressional 

appropriations have prohibited ATF from using any 

funds or salaries in connection with the 

consolidation or centralization of records of 

acquisition and disposition of firearms maintained 

by FFLs. See Treasury, Postal Service, and General 

Government Appropriations Act, 1980, Public Law 

96–74, 93 Stat. 560 (1979). This annual restriction 

became permanent in 2011. See Public Law 112– 

55, 125 Stat. 632 (2011). 

75As a general matter, the Department’s 

prosecutorial practices and priorities are set forth in 

the ‘‘Principles of Federal Prosecution’’ in the DOJ 

Justice Manual §§ 9–27.000, et seq. Section 9– 

27.260 (‘‘Initiating and Declining Charges— 

Impermissible Considerations’’) reads, in pertinent 

part, ‘‘In determining whether to commence or 

recommend prosecution or take other action against 

a person, the attorney for the government should 

not be influenced by . . . [t]he person’s race, 

religion, gender, ethnicity, national origin, sexual 

orientation, or political association, activities, or 

beliefs.’’ 

76See Public Law 90–351, sec. 901(a), 82 Stat. 

225–26. 

identifying the original purchaser of a 

firearm later used in a violent crime.72

Although this demographic information 

is used for background check purposes, 

it is not maintained by the NICS. The 

NICS, which is administered by the FBI, 

is required by law to destroy all 

identifying information on prospective 

purchasers within 24 hours of providing 

a response that the transfer may 

proceed.73 ATF may also inspect 

individual ATF Forms 4473 containing 

personally identifiable information held 

by FFLs, but only for limited regulatory 

or law enforcement functions— 

specifically, during inspections, and in 

the course of investigations, such as 

when tracing firearms linked to 

individual criminal investigations. 

Finally, statutory and appropriations 

restrictions prohibit ATF from 

promulgating any rule requiring the 

maintenance of a database or other 

information repository of the race or 

ethnicity of firearm purchasers or 

licensees.74 For these reasons, the 

Department cannot require the 

systematic collection of such 

demographic information for statistical, 

programmatic, or other purposes as part 

of this rule. 

Commenter’s remaining suggestions 

regarding racial equality are beyond the 

scope of this rule.75 This rule 

implements the GCA, which was 

passed, in part, to help Federal, State, 

and local law enforcement prevent 

illicit firearms trafficking within their 

respective jurisdictions.76 Specifically, 

this rule is intended, in part, to address 

the proliferation of unserialized ‘‘ghost 

guns,’’ which are increasingly being 

recovered at crime scenes, and law 

enforcement’s difficulty in tracing them 

when recovered. The rule accomplishes 

this objective by clarifying the 

serialization and recordkeeping 

requirements that preserve ATF’s ability 

to trace firearms for Federal, State, local, 

and international law enforcement 

wherever firearm violence may occur. 

B. Issues Raised in Opposition to the 

Rule 

Thousands of commenters broadly 

expressed opposition to the NPRM with 

numerous form letters submitted. Over 

7,000 commenters simply opposed 

without providing concrete reasons 

while the majority raised specified 

concerns about the proposed rule. ATF 

received comments from a variety of 

interested parties, including from FFL 

retailers and manufacturers, 

organizations, various lawmakers, 

knowledgeable gun enthusiasts, and 

persons with law enforcement 

backgrounds. As discussed below, 

numerous other commenters raised 

various concerns about the 

Department’s proposed amendments to 

ATF regulations. These reasons 

included constitutional and statutory 

authority concerns, issues with the 

clarity and effect of the proposed 

definitions and changes to 

recordkeeping and marking 

requirements, and concerns about the 

public safety goals of the Department in 

promulgating this rule. 

1. Constitutional Concerns 

a. Violates the Ex Post Facto Clause 

Comments Received 

Several hundred commenters opposed 

to the rule stated that it directly violates 

Clause 3 of Article I, Section 9, of the 

United States Constitution, which 

prohibits ‘‘ex post facto Law[s].’’ These 

commenters’ opposition comes from 

their belief that, once the proposed rule 

goes into effect, possession of items that 

are currently lawful would be no longer 

legal, and that the new prohibition 

would constitute an ex post facto law. 

Department Response 

The Department disagrees that the 

proposed rule violates the Ex Post Facto 

Clause. In Calder v. Bull, 3 U.S. (3 Dall.) 

386 (1798), the Supreme Court set out 

four types of laws that violate the Ex 

Post Facto Clause: 

1st. Every law that makes an action, done 

before the passing of the law, and which was 

innocent when done, criminal; and punishes 

such action. 2nd. Every law that aggravates 

a crime, or makes it greater than it was, when 

committed. 3rd. Every law that changes the 

punishment, and inflicts a greater 

punishment, than the law annexed to the 

crime, when committed. 4th. Every law that 

alters the legal rules of evidence, and 

receives less, or different, testimony, than the 

law required at the time of the commission 

of the offence, in order to convict the 

offender. 

Id. at 390. Citing Calder, the Supreme 

Court has explained that a ‘‘law must be 

retrospective—that is, it must apply to 

events occurring before its enactment— 

and it must disadvantage the offender 

affected by it by altering the definition 

of criminal conduct or increasing the 

punishment for the crime’’ to be 

considered as falling within the ex post 

facto prohibition. Lynce v. Mathis, 519 

U.S. 433, 441 (1997) (citation and 

internal quotation marks omitted). 

Courts have consistently recognized that 

regulating the continued or future 

possession of a firearm that is already 

possessed does not implicate the Ex 

Post Facto Clause because such a 

regulation does not criminalize past 

conduct. See, e.g., United States v. 

Pfeifer, 371 F.3d 430, 436–37 (8th Cir. 

2004); United States v. Mitchell, 209 

F.3d 319, 322 (4th Cir. 2000); United 

States v. Brady, 26 F.3d 282, 290–91 (2d 

Cir. 1994); United States v. Gillies, 851 

F.2d 492, 495–96 (1st Cir. 1988) (Breyer, 

J.); United States v. D’Angelo, 819 F.2d 

1062, 1065–66 (11th Cir. 1987); see also 

Samuels v. McCurdy, 267 U.S. 188, 193 

(1925) (rejecting Ex Post Facto Clause 

challenge to statute that prohibited the 

post-enactment possession of 

intoxicating liquor, even when the 

liquor was lawfully acquired before the 

statute’s enactment). 

Here, penalties would result only 

from the future failure to mark firearms. 

For FFLs that already have unmarked 

firearms kits, frames, or receivers, they 

have 60 days from the effective date of 

the rule to appropriately mark these 

firearms. See 27 CFR 478.92(a)(4)(vi). 

Moreover, as this rule in other respects 

simply describes the proper application 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24675 

of the terms Congress used in various 

provisions of the GCA, it does not 

impose liability independent of the 

preexisting requirements of those 

statutes. For these reasons, the 

Department disagrees with commenters’ 

assertions that the rule violates the Ex 

Post Facto Clause. 

b. Violates the First Amendment 

Comments Received 

A few commenters raised concerns 

that the proposed definitions violate the 

First Amendment. One commenter, an 

organization of artisans who create 

artistic arrangements that use ‘‘arbitrary 

components, some of which are semiprocessed firearm components such as 

barrels [and] pistol slides,’’ is concerned 

that if artisans are required to check 

with ATF on its opinion when using 

novel or arbitrary components in their 

artwork, this requirement would be a 

prior restraint on protected expression. 

The commenting organization stated 

that ATF’s definitions are so vague that 

it does not know what ATF would 

consider novel ‘‘modular’’ designs that 

might be considered a frame or receiver. 

Further, the organization claimed that 

under the nonexclusive lists in the 

proposed definition just about any 

major gun part could check more than 

one box on ATF’s ‘‘unlimited features’’ 

and be considered a frame or receiver. 

As such, the organization argued that 

the vague, open-ended definitions in the 

NPRM ‘‘would chill an artisan—one 

with a specific desire not to use any gun 

part which could be considered a 

‘firearm’ and thus require the employ of 

an FFL—from engaging in First 

Amendment protected expression.’’ 

Other commenters stated that the NPRM 

also raises First Amendment concerns 

because the Director would be able to 

determine when a component has 

become a firearm based on a company’s 

instructions and how a company 

markets the product. 

Department Response 

The Department agrees with the 

commenters who asserted that the 

proposed definition was potentially 

confusing, but disagrees with the 

commenters’ First Amendment 

objections. First, the Department 

recognizes that the definition as 

proposed would have made it more 

difficult for artisans and others to 

determine whether they would be 

acquiring a ‘‘frame or receiver’’ subject 

to regulation. For this reason, and 

because the Department agrees with 

commenters that the definition of 

‘‘firearm’’ in 18 U.S.C. 921(a)(3)(B) is 

best read to mean that a single part of 

a weapon or device is the frame or 

receiver, this rule adopts subsets of the 

proposed definition of ‘‘frame or 

receiver’’ to define ‘‘frame’’ and 

‘‘receiver’’ so that licensees and the 

public can make this determination 

without an ATF classification. The 

Department has accordingly established 

new distinct definitions for frames with 

respect to handguns; receivers with 

respect to rifles, shotguns, and projectile 

weapons other than handguns; and 

frames or receivers for firearm mufflers 

or silencers. 

The Department, however, does not 

agree with commenters that the rule 

would violate the First Amendment 

rights of artisans. The Supreme Court 

has held the First Amendment is not 

implicated by the enforcement of a 

regulation of general application not 

targeted at expressive activity. See 

Arcara v. Cloud Books, Inc., 478 U.S. 

697, 707 (1986) (upholding closure 

sanction of ‘‘an establishment used for 

prostitution’’ where respondents also 

‘‘happen to sell books’’). First 

Amendment scrutiny ‘‘has no relevance 

to a statute directed at . . . nonexpressive activity,’’ and applies ‘‘only 

where it was conduct with a significant 

expressive element that drew the legal 

remedy in the first place.’’ Id. at 706– 

707; see also Wright v. City of St. 

Petersburg, Florida, 833 F.3d 1291, 1298 

(11th Cir. 2016) (‘‘First Amendment 

scrutiny ha[d] no relevance to [a 

trespass ordinance] directed at imposing 

sanctions on nonexpressive activity.’’ 

(internal quotation marks omitted)); 

Talk of the Town v. Department of 

Finance & Business Servs ex rel. Las 

Vegas, 343 F.3d 1063, 1069 (9th Cir. 

2003) (section of Las Vegas Code barring 

consumption of alcohol in places that 

lack valid liquor license—including 

exotic dancing establishments—‘‘in no 

way can be said to regulate conduct 

containing an element of protected 

expression’’). The definitions at issue 

are not targeting expressive conduct of 

any kind but are part of a ‘‘regulation of 

general application’’ clarifying the 

definition of frame and receiver and the 

marking requirements thereof. As such, 

the Department’s position is that the 

First Amendment is not implicated by 

this rule. 

However, in an abundance of caution 

and because artwork in general is 

expressive conduct entitled to First 

Amendment protection, see Texas v. 

Johnson, 491 U.S. 397, 404 (1989), and 

assuming this regulation somehow 

affects that conduct, the definitions still 

do not target expressive conduct and 

strict scrutiny review is not appropriate 

under the First Amendment analysis set 

out in United States v. O’Brien, 391 U.S. 

367 (1968). ‘‘[W]hen ‘speech’ and 

‘nonspeech’ elements are combined in 

the same course of conduct, a 

sufficiently important governmental 

interest in regulating the nonspeech 

element can justify incidental 

limitations on First Amendment 

freedoms.’’ Id. at 376. Under an O’Brien 

analysis— 

a government regulation is sufficiently 

justified [1] if it is within the constitutional 

power of the Government; [2] if it furthers an 

important or substantial governmental 

interest; [3] if the governmental interest is 

unrelated to the suppression of free 

expression; and [4] if the incidental 

restriction on alleged First Amendment 

freedoms is no greater than is essential to the 

furtherance of that interest. 

Id. at 377. 

First, ‘‘the Government may 

constitutionally regulate the sale and 

possession of firearms.’’ Wilson v. 

Lynch, 835 F.3d 1083, 1096 (9th Cir. 

2016). Second, courts have repeatedly 

held that public safety and the 

prevention of crime are not only 

substantial, but compelling 

governmental interests. See United 

States v. Salerno, 481 U.S. 739, 750 

(1987); Mai v. United States, 952 F.3d 

1106, 1116 (9th Cir. 2020); Worman v. 

Healey, 922 F.3d 26, 39 (1st Cir. 2019); 

New York State Rifle & Pistol Ass’n v. 

Cuomo, 804 F.3d 242, 261 (2d Cir. 

2015); Kolbe v. Hogan, 849 F.3d 114, 

139 (4th Cir. 2017); Horsley v. Trame, 

808 F.3d 1126, 1132 (7th Cir. 2015). 

Third, ‘‘the Government’s efforts to 

reduce gun violence’’ are not directed at 

any expressive conduct and cannot be 

construed to be related to the 

suppression of free expression in any 

way. Wilson, 835 F.3d at 1096–97. 

Fourth, the definitions do not ban the 

private making of a firearm nor the 

unregulated possession of non-frame or 

non-receiver firearms parts. Nor do the 

definitions ban the possession of a 

frame or receiver, but only require that 

a frame or receiver be marked; therefore, 

any burden is ‘‘incidental’’ and 

‘‘minimal.’’ Id. Because the regulation 

‘‘satisfies each of the O’Brien 

conditions, it survives intermediate 

scrutiny.’’ Id. at 1097 (finding ATF’s 

Open Letter to Federal Firearms 

Licensees informing them that the 

presentment of a purported purchaser’s 

medical marijuana registry card would 

give them cause to deny the sale as 

violating 18 U.S.C. 922(d)(3) did not 

violate the First Amendment even if 

having the card was considered 

expression). Therefore, even if the 

O’Brien standard applies, the definitions 

do not violate the First Amendment. See 

Arcara, 478 U.S. at 707 (‘‘O’Brien . . . 


jspears on DSK121TN23PROD with RULES2
24676 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

77There is no historical support for the idea that 

private individuals regularly and easily 

manufactured firearms at home at the time of the 

Founding. ‘‘[F]irearms were not like apple pies, 

which a typical family could make at home . . . . 

[T]hey were items of commerce that were nearly 

impossible to produce without specialized 

equipment and skill.’’ David B. Kopel, Does the 

Second Amendment Protect Commerce?, 127 Harv 

L. Rev. Forum 230, 237 (Apr. 11, 2014). 

has no relevance [to a rule regulating] 

nonexpressive activity’’). 

c. Violates the Second Amendment 

Comments Received 

A majority of commenters opposed to 

the NPRM objected to it on grounds that 

any changes to the definitions or the 

creation of new requirements that 

undermine the Second Amendment are 

unconstitutional, stating that the right to 

build firearms dates back to the 

founding of the Republic and that 

requiring markings on PMFs is an 

unconstitutional infringement of their 

Second Amendment rights. Commenters 

stated that ATF has encouraged 

hobbyists to fabricate firearms for their 

personal use and that the new 

requirements will restrain them from 

exercising their constitutional rights. 

Others objected saying that the NPRM 

failed to include relevant Second 

Amendment analysis. One commenter 

provided its own analysis, claiming that 

since District of Columbia v. Heller, 554 

U.S. 570 (2008), a majority of gun 

control laws are examined under a 

reasonableness standard, which requires 

the regulation be a reasonable method 

for achieving the objectives of the 

regulation. Commenters claimed that 

ATF’s proposed regulations would fail 

to meet the reasonableness standard 

because the evidence the agency cites 

actually proves that unfinished lower 

receivers are not even a marginal 

contributor to America’s gun violence 

problem. Under their calculations, the 

commenters estimate that PMFs have 

been used only .837 percent of the time 

in deaths resulting from gun violence. 

Commenters concluded the proposed 

regulations are not a reasonable method 

to achieve the goal of reducing gun 

violence and therefore do not pass 

constitutional muster since the data 

does not demonstrate that regulating 

unfinished lower receivers will result in 

a statistically significant reduction of 

deaths from firearms. 

Department Response 

The Department disagrees with 

commenters that the new requirements 

are unconstitutional under the Second 

Amendment. First, the GCA and this 

rule do not prohibit individuals from 

assembling or otherwise making their 

own firearms from parts for personal 

use, such as self-defense or other lawful 

purposes. Neither the GCA nor this rule 

prohibits law-abiding citizens from 

completing, assembling, or transferring 

firearms without a license as long as 

those persons are not engaged in the 

business of manufacturing or importing 

firearms for sale or distribution, or 

dealing in firearms, or transacting curio 

or relic firearms in a manner requiring 

a license. See 18 U.S.C. 922(a)(1), 

923(a)–(b). 

Second, this final rule is consistent 

with the Supreme Court’s decision in 

District of Columbia v. Heller, 554 U.S. 

570 (2008). There are compelling 

governmental interests in requiring 

privately made firearms to be marked 

and recorded whenever they are 

accepted into the business or collection 

inventories of licensees. The Supreme 

Court recognized in Heller, 554 U.S. at 

626–27 & n.26, that ‘‘presumptively 

lawful regulatory measures’’ include 

those ‘‘imposing conditions and 

qualifications on the commercial sale of 

arms.’’ PMFs, like commercially 

produced firearms, must be able to be 

traced through the records of licensees 

when the PMFs are involved in crimes. 

PMFs cannot be traced through a 

licensee’s records without the 

manufacturers’ serial numbers placed 

on PMFs by licensees, as required by 

this rule. Cf. United States v. 

Marzzarella, 614 F.3d 85, 99 (3d Cir. 

2010) (concluding that even if strict 

scrutiny were to apply, 18 U.S.C. 922(k) 

(prohibiting possession of firearms with 

obliterated serial numbers) would be 

upheld under the Second Amendment 

because ‘‘serial number tracing serves a 

governmental interest in enabling law 

enforcement to gather vital information 

from recovered firearms,’’ and 

‘‘[b]ecause it assists law enforcement in 

this manner, we find its preservation is 

not only a substantial but a compelling 

interest’’). 

Commenters also suggested that a 

licensing requirement for the 

manufacture of firearms violates the 

Second Amendment. Preexisting law 

requires those engaged in the business 

of manufacturing, importing, or dealing 

firearms to be licensed. That 

requirement does not burden the ability 

of non-prohibited people to buy, sell, or 

possess firearms, and no court has 

opined that the Second Amendment 

protects the right to engage in the 

business of unlicensed manufacturing. 

Heller ‘‘did not touch in any way on an 

individual’s right to manufacture or 

create those arms.’’ Defense Distributed 

v. United States Dep’t of State, 121 F. 

Supp. 3d 680, 699 (W.D. Tex. 2015) 

(finding prepublication approval for 

software data files, project files, coding, 

and model for producing 3D printed 

firearms was a burden that fell ‘‘well 

short of that generally at issue in Second 

Amendment cases’’). As stated above, 

the regulation does not ban the private 

making of a firearm.77 See id. (plaintiffs 

‘‘are not prohibited from manufacturing 

their own firearms, nor are they 

prohibited from keeping and bearing 

other firearms’’). 

In rejecting a Second Amendment 

challenge to the analogous requirement 

to be licensed as a dealer in firearms, 

the Fourth Circuit found the licensing 

requirement ‘‘covers only the 

commercial sale of firearms. It affects 

only those who regularly sell firearms 

. . . . It explicitly excludes the vast 

majority of noncommercial sales.’’ 

United States v. Hosford, 843 F.3d 161, 

166 (4th Cir. 2016). The same findings 

apply to persons ‘‘regularly’’ 

manufacturing firearms. Like section 

922(a) of the GCA, the regulation 

‘‘imposes a mere condition or 

qualification. Though framed as a 

prohibition against unlicensed firearm 

[commerce], the law is in fact a 

requirement that those who engage in 

the [business] of firearms obtain a 

license.’’ Id. And this licensing 

requirement ‘‘is a crucial part of the 

federal regulatory scheme.’’ Id. at 168; 

see also United States v. Focia, 869 F.3d 

1269, 1286 (11th Cir. 2017) (prohibiting 

transfers between unlicensed 

individuals in different states ‘‘does not 

operate to completely prohibit [the 

defendant] or anyone else, for that 

matter, from selling or buying firearms;’’ 

instead, it ‘‘merely’’ imposes 

‘‘conditions and qualifications on the 

commercial sale of arms’’ (internal 

quotation marks omitted)); United 

States v. Nowka, 2012 WL 2862061, at 

*6 (N.D. Ala. May 10, 2012) 

(‘‘[Plaintiff’s] right to buy or sell a 

firearm is not abridged. It is 

regulated.’’). 

In some ways similar to the 

regulation, but in other ways more farreaching, a San Diego City ordinance 

prohibits the possession, purchase, sale, 

receipt, and transportation of nonserialized firearms and unfinished 

frames and receivers. A lawsuit was 

brought challenging the ordinance as 

imposing ‘‘a blanket prohibition’’ upon 

a Second Amendment right to ‘‘selfmanufacture all firearms in common use 

for self-defense and other lawful 

purposes.’’ Fahr v. City of San Diego, 

2021 WL 4895974, at *5 (S.D. Cal. Oct. 

20, 2021). The district court disagreed, 

finding the ordinance ‘‘neither strips 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24677 

persons of access to any serialized, 

California-compliant firearm, including 

AR–15s, nor does it prevent persons 

from assembling any class of Californiacompliant firearm using pre-serialized 

frames or receivers.’’ Id. at *6. The court 

further found that, assuming the 

ordinance regulates conduct protected 

by the Second Amendment, it ‘‘does not 

severely burden Second Amendmentprotected conduct, but merely regulates 

it.’’ Id. at *9; see also id. at *10 (because 

the ordinance ‘‘targets only nonserialized firearms and unfinished 

frames and unfinished receivers . . . 

that bypass background checks . . . and 

that are untraceable . . . this Court 

finds that the Ordinance is a reasonable 

fit for achieving the City’s objectives of 

decreasing the threat that ghost guns 

pose to the City’s stated substantial and 

important interests,’’ i.e., ‘‘[p]ublic 

safety and crime prevention’’). 

Further, where commenters believed 

that the rule would require them to 

mark their PMFs, they argued that 

imposing such marking requirements is 

unconstitutional under the Second 

Amendment because the right to build 

firearms dates back to the founding of 

the Republic. Some commenters also 

believed that requiring markings of any 

kind on firearms is unconstitutional 

under the Second Amendment. As 

stated above, in Marzzarella, the Third 

Circuit rejected as ‘‘unavailing’’ the 

premise that ‘‘unmarked firearms’’ are 

‘‘a constitutionally recognized class of 

firearms.’’ 614 F.3d at 93. The court 

found that requiring a visible serial 

number ‘‘d[oes] not bar’’ an individual 

‘‘from possessing any otherwise 

lawfully marked firearm,’’ id. at 94, and 

thus the ‘‘burden imposed by the law 

does not severely limit the possession of 

firearms,’’ id. at 97. Moreover, this 

requirement ‘‘serves a law enforcement 

interest in enabling the tracing of 

weapons via their serial numbers’’ and 

in ‘‘assist[ing] law enforcement by 

making it possible to use the serial 

number of a firearm recovered in a 

crime to trace and identify its owner 

and source.’’ Id. at 98; see also Fahr, 

2021 WL 4895974, at *10 (‘‘It is a matter 

of common sense that tracing firearms 

enhances public safety and aids crime 

solving.’’ (internal quotation marks 

omitted)); id. at *11 (‘‘firearms tracing 

has become a critical tool for modern 

firearms investigations and 

prosecutions, which the prevalence of 

ghost guns threatens to upend’’ (internal 

quotation marks omitted)). 

Although commenters argued that 

Heller established a ‘‘reasonableness’’ 

standard under which the regulation 

fails because there is low usage of PMFs 

in crimes, this final rule provides 

revised information demonstrating that 

the number of suspected PMFs 

recovered at crime scenes has been 

increasing exponentially. As a matter of 

common sense, unserialized firearms 

are inherently attractive to criminals, 

and therefore pose a risk to public 

safety. And, as noted in Section II.B of 

this preamble, there has been a 

substantial increase in the number of 

PMFs recovered from crime scenes in 

recent years. The agency does not need 

to wait until a certain number of crimes 

are committed in order to address a 

growing problem. Moreover, this rule 

serves the compelling governmental 

interest of preventing unserialized 

firearms from proliferating throughout 

the country, as recognized in 

Marzzarella decision. Finally, this rule 

is not a prohibition, but only a 

regulation that imposes a minimal 

burden on the possession of firearms. 

d. Violates the Fourth Amendment 

Right to Privacy 

Comments Received 

Several commenters claimed the 

proposed rule violates their right to 

privacy under the Fourth Amendment. 

These commenters believe that the 

proposed rule requires persons to 

disclose firearms they have privately 

made on Form 4473, or that there is de 

facto registration occurring in the 

requirement that FFLs mark the PMFs 

they acquire. Other commenters stated 

that enforcement of the proposed rule 

would lead to a violation of their 

constitutional right to privacy in regards 

to their property if the government 

knows how many weapons each 

individual owns. 

Department Response 

The commenters are not correct in 

their belief that the rule requires 

persons to disclose firearms they have 

made on Form 4473. Under the 

proposed and final rule, there are no 

recordkeeping or marking requirements 

for personal, non-NFA firearms that are 

privately made. As to the recordkeeping 

and marking requirements for the 

licensees engaged in the business of 

manufacturing or dealing in firearms, 

those records are not in the custody of 

the government, but are retained by the 

licensee until they discontinue 

business. See 18 U.S.C. 923(g)(4). 

Additionally, while the proposed rule in 

no way establishes a registry of firearms, 

it is worthwhile noting that even actual 

registration of NFA firearms has never 

been found to violate a Fourth 

Amendment right to privacy. 

The Department also does not agree 

that the proposed rule violates a 

constitutional right to privacy in regard 

to commenters’ property if the 

government knows how many weapons 

an individual possesses. ‘‘The United 

States Constitution does not expressly 

guarantee a right to privacy, but the 

Supreme Court has held that a right to 

privacy does exist within the liberty 

component of the Fourteenth 

Amendment.’’ See Padgett v. Donald, 

401 F.3d 1273, 1280 (11th Cir. 2005). 

Courts have recognized a privacy 

interest in avoiding disclosure of certain 

personal matters. See id. 

‘‘[N]ot all disclosures of private 

information will trigger constitutional 

protection.’’ Doe No. 1 v. Putnam 

County, 344 F. Supp. 3d 518, 540 

(S.D.N.Y. 2018) (finding courts have 

found a right to privacy in a ‘‘limited set 

of factual circumstances’’ involving 

one’s personal financial or medical 

information, i.e., information of a 

‘‘highly personal nature’’). ‘‘[T]he 

question is not whether individuals 

regard [particular] information about 

themselves as private, for they surely 

do, but whether the Constitution 

protects such information.’’ DM v. 

Louisa County Dep’t of Human Services, 

194 F. Supp. 3d 504, 508–09 (W.D. Va. 

2016) (finding no right to privacy of 

medical information) (internal quotation 

marks omitted). Information regarding 

firearms ownership or possession is of 

neither the medical nor financial 

variety, and no court has found this 

information to be constitutionally 

protected. See Doe 1, 344 F. Supp. 3d 

at 541 (‘‘Disclosure of one’s name, 

address, and status as a firearms license 

[holder] is not one of the ‘very limited 

circumstances’ in which a right to 

privacy exists.’’). 

e. Violates the Fifth Amendment— 

Unconstitutionally Vague 

Comments Received 

Numerous commenters objected to the 

new definitions on grounds that the 

definitions are so vague that they violate 

the Due Process Clause of the Fifth 

Amendment. Citing to Christopher v. 

SmithKline Beecham Corp, 567 U.S. 

142, 155–56 (2012), commenters stated 

that ATF must ‘‘provide regulated 

parties ‘fair warning of the conduct [the 

regulation] prohibits or requires’ ’’; 

otherwise, such ambiguity undermines 

due process and deprives market 

participants of notice about the law. 

Here, the commenters stated the 

definitions of ‘‘firearms,’’ ‘‘split or 

modular frame or receiver,’’ and 

‘‘readily’’ offer no clear guidance or 

clarity in determining the scope of the 

terms and therefore are impermissibly 

vague. Further, commenters stated that 


jspears on DSK121TN23PROD with RULES2
24678 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

78Forgings, castings, extrusions, and machined 

bodies of firearms that are clearly identifiable as 

incomplete firearm frames or receivers have been 

regulated for purposes of importation and 

exportation as ‘‘defense articles’’ since at least 1939. 

See International Traffic in Arms, Ammunition, 

etc., 22 CFR 171.6, 1939 Supp. 1318; 32 CFR 1.6, 

1939 Supp. 2326 (now 22 CFR 120.6 and 27 CFR 

447.22). They are also considered ‘‘imported parts’’ 

for purposes of the prohibition against assembling 

nonsporting semiautomatic rifles or shotguns under 

18 U.S.C. 922(r). See 27 CFR 478.39(c)(1). Under 

this rule, only forgings, castings, and machined 

bodies that are clearly identifiable as a component 

part of a weapon and that are designed to, or may 

readily be completed, assembled, restored, or 

otherwise converted to a functional state are 

regulated as ‘‘frames’’ or ‘‘receivers.’’ 

because the only way the public can get 

clarity is through the non-binding and 

non-public classification letters process, 

due process concerns are further 

compounded as entities are denied an 

opportunity to know what the law is 

and how to conform their conduct 

accordingly. 

Department Response 

In light of the many cases rejecting 

such challenges, the Department does 

not believe the term ‘‘readily’’ is vague. 

Nonetheless, to avoid any doubt, the 

final rule provides additional clarity on 

the application of ‘‘readily.’’ The rule 

now expressly excludes from the 

definitions of ‘‘frame or receiver,’’ a 

‘‘forging, casting, printing, extrusion, 

unmachined body, or similar article that 

has not yet reached a stage of 

manufacture where it is clearly 

identifiable as an unfinished component 

part of a weapon (e.g., unformed block 

of metal, liquid polymer, or other raw 

material).’’ Thus, the definition of 

‘‘readily’’ is not applied to items in a 

primordial state that are not clearly 

identifiable as unfinished weapon (i.e., 

pistol, revolver, rifle, or shotgun) frames 

or receivers. Moreover, the final rule 

explains that, when issuing a 

classification, the Director may consider 

any associated templates, jigs, molds, 

equipment, tools, instructions, guides, 

or marketing materials that are sold, 

distributed, or possessed with the item 

or kit, or otherwise made available by 

the seller or distributor of the item or 

kit, to the purchaser or recipient of the 

item or kit. The final rule further 

provides detailed examples of when an 

unfinished frame or receiver billet, 

blank, or parts kit may be considered a 

‘‘frame or receiver.’’ For example, a 

partially complete billet or blank of a 

frame or receiver is a ‘‘frame or 

receiver’’ when it is sold, distributed, or 

possessed with a compatible jig or 

template, allowing a person using 

online instructions and common hand 

tools to complete the frame or receiver 

efficiently, quickly, and easily ‘‘to 

function as a frame or receiver,’’ a term 

which is also explained in the final rule. 

These revisions make it clear that 

manufacturers will be able to continue 

to obtain unfinished billets or blanks 

from their suppliers for further 

manufacture without requiring that the 

producer be licensed, mark such items, 

or maintain records of production and 

disposition. This is because their 

suppliers are not selling, distributing, or 

otherwise making available to their 

customers any jigs, templates, or other 

items that allow them to be readily 

converted to function as a frame or 

receiver. 

The Department disagrees with 

commenters that the explanation in the 

proposed rule of how ATF would 

determine which portion of a ‘‘firearm’’ 

is a frame or receiver in a split or 

modular weapon, and what the term 

‘‘readily’’ encompasses, is 

unconstitutionally vague. To begin, the 

rule explains ATF’s understanding of 

the statutory terms at issue and 

describes how those terms apply to 

particular circumstances, thus providing 

greater clarity about the statutory terms 

involved. To the extent commenters are 

concerned that the statutory 

requirements are unclear, that is an 

objection about the statute, not the rule. 

In any event, however, the terms 

employed in the rule are not 

unconstitutionally vague. ‘‘It is a basic 

principle of due process that an 

enactment is void for vagueness if its 

prohibitions are not clearly defined.’’ 

Grayned v. City of Rockford, 408 U.S. 

104, 108 (1972). A law is impermissibly 

vague if it ‘‘fails to provide a person of 

ordinary intelligence fair notice of what 

is prohibited, or is so standardless that 

it authorizes or encourages 

discriminatory enforcement.’’ FCC v. 

Fox Television Stations, Inc., 567 U.S. 

239, 253 (2012) (internal quotation 

marks omitted). However, 

‘‘[c]ondemned to the use of words, we 

can never expect mathematical certainty 

from our language.’’ Grayned, 408 U.S. 

at 110; see also Ward v. Rock Against 

Racism, 491 U.S. 781, 794 (1989) 

(‘‘perfect clarity and precise guidance 

have never been required even of 

regulations that restrict expressive 

activity’’). 

Commenters objected to the term 

‘‘readily’’ as vague. The term ‘‘readily’’ 

is defined in the rule to explain when 

a partially complete, disassembled, or 

nonfunctional frame or receiver is 

considered a ‘‘frame or receiver’’ under 

18 U.S.C. 921(a)(3)(B); when a weapon, 

including a weapon parts kit, is 

considered a ‘‘firearm’’ under 18 U.S.C. 

921(a)(3)(A); and when such frames or 

receivers are considered ‘‘destroyed.’’ 

These terms are easily understood to 

mean that if there is a weapon parts kit 

that may readily be completed, 

assembled, restored, or otherwise 

‘‘converted’’ to a functional state (i.e., to 

expel a projectile), that parts kit is, 

itself, a ‘‘firearm.’’ Likewise, it is easy to 

understand that if there is a partially 

complete, disassembled, or 

nonfunctional frame or receiver that 

may readily be completed, assembled, 

restored, or otherwise converted to a 

functional state (i.e., to house or provide 

a structure for the applicable fire control 

component), that housing or structure 

is, itself, a ‘‘frame’’ or ‘‘receiver.’’ No 

specialized knowledge is needed to 

understand how the term ‘‘readily’’ is to 

be applied. Persons who manufacture or 

possess weapon or frame or receiver 

parts kits, aggregations of parts, partially 

complete, or nonfunctional frames or 

receivers, are clearly on notice that what 

they are manufacturing, making, selling, 

distributing, receiving, or possessing are 

items subject to regulation if they only 

require minor additional work to be 

made functional. In sum, persons who 

make, transfer, receive, or possess 

partially complete firearm frames or 

receivers are on notice that those items 

are regulated if they may readily be 

converted.78 On the other end of the 

spectrum, it is easy for persons to 

comprehend that if what was a ‘‘frame 

or receiver’’ of a weapon can no longer 

function as such, and cannot efficiently, 

quickly, or easily be converted back to 

a functional state, that item is no longer 

a ‘‘frame or receiver,’’ or ‘‘firearm,’’ 

because it has been destroyed. 

Moreover, ‘‘readily’’ has been 

repeatedly—and consistently—defined 

by case law. In New York State Rifle & 

Pistol Ass’n v. Cuomo, 804 F.3d 242 (2d 

Cir. 2015), the plaintiffs challenged a 

State statute criminalizing the 

possession of magazines that ‘‘can be 

readily restored or converted to accept’’ 

more than ten rounds of ammunition as 

vague because ‘‘whether a magazine 

‘can be readily restored or converted’ 

depends upon the knowledge, skill, and 

tools available to the particular 

restorer.’’ Id. at 266. The Second Circuit 

rejected that argument, finding that this 

‘‘statutory language dates at least to the 

1994 federal assault weapons ban’’ and 

‘‘there is no record evidence that it has 

given rise to confusion at any time in 

the past two decades.’’ Id. 

Indeed, ‘‘readily’’ dates back even 

further, appearing in the NFA’s 

definition of ‘‘machinegun,’’ where it 

has repeatedly been upheld against 

vagueness challenges. See United States 

v. Catanzaro, 368 F. Supp. 450, 453–54 

(D. Conn. 1973) (rejecting argument that 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24679 

79See also U.S. v. Wojcikiewicz, 403 F. App’x 

483, 486 (11th Cir. 2010) (same with disassembled 

rifles); United States v. Kelly, No. 05–4775, 2007 

WL 2309761, at *5 (4th Cir. Aug. 14, 2007) (the 

argument that 26 U.S.C. 5845(b) is 

unconstitutionally vague is meritless); United 

States v. Kent, 175 F.3d 870, 878 (11th Cir. 1999) 

(rejecting vagueness challenge where disassembled 

short-barreled Colt AR–15 could be readily restored 

to operate as a short-barreled rifle); United States 

v. Drasen, 845 F.2d 731, 737–38 (7th Cir. 1988) 

(rejecting vagueness challenge to the phrase 

‘‘readily restored’’ in 26 U.S.C. 5845(c) defining 

‘‘rifle’’); U.S. v. M–K Specialties Model M–14 

Machinegun, 424 F. Supp. 2d 862, 872 (N.D. W. Va. 

2006) (rejecting vagueness challenge to the phrase 

‘‘readily restored’’ in 26 U.S.C. 5845(b); cf. Phelps 

v. Budge, 188 F. App’x 616, 618 (9th Cir. 2006) 

(Nevada statute defining deadly weapon as, among 

other things, any weapon or device which was 

‘‘readily capable of causing substantial bodily harm 

or death’’ was not unconstitutionally vague); 

Coalition of New Jersey Sportsmen v. Whitman, 44 

F. Supp. 2d 666, 681 (D.N.J. 1999), aff’d, 263 F.3d 

157 (3d Cir. 2001) (New Jersey statute criminalizing 

‘‘any combination of parts from which an assault 

firearm may be readily assembled’’ was not 

unconstitutionally vague); Botosan v. Paul McNally 

Realty, 216 F.3d 827, 836–37 (9th Cir. 2000) (term 

‘‘readily achievable’’ and factors set forth in the 

Americans with Disabilities Act ‘‘can hardly be 

considered vague’’); United States v. Quiroz, 449 

F.2d 583, 585 (9th Cir. 1971) (the definition of 

‘‘firearm’’ in section 921(a)(3) was not 

unconstitutionally vague with respect to a ‘‘readily 

convertible’’ starter gun); United States v. 16,179 

Molso Italian .22 Caliber Winlee Derringer 

Convertible Starter Guns, 443 F.2d 463, 464–65 (2d 

Cir. 1971) (same). 

80Moreover, to the extent there is uncertainty 

about a particular item, upon submission, ATF will 

render a classification, a service ATF has long 

provided. See Sig Sauer, Inc. v. Brandon, 826 F.3d 

598, 599–600 (1st Cir. 2016); see also United States 

v. Zhen Zhou Wu, 711 F.3d 1, 15 (1st Cir. 2013) 

(rejecting a vagueness challenge to the regulatory 

framework of the Arms Export Control Act and 

noting there is a ‘‘determination process’’ to ‘‘allow 

private parties to obtain an official government 

answer on whether an item is covered . . . before 

they engage in potentially unlawful conduct, a 

feature that further mitigates any concern about the 

law trapping [the] unwary’’ (citation omitted)). 

phrase ‘‘which may be readily restored 

to fire’’ in the NFA ‘‘is not sufficiently 

definite to provide adequate warning as 

to the kinds of weapons included’’); 

United States v. M–K Specialties Model 

M–14 Machinegun, 424 F. Supp. 2d 862, 

872 (N.D. W. Va. 2006) (the parties 

agreed ‘‘the ordinary meaning of the 

term ‘readily restored’ should be used 

when applying section 5845(b) [of the 

NFA] . . . the statute’s terms should be 

easily understood by a person of 

ordinary intelligence’’).79 While 

Congress did not define ‘‘readily,’’ 

courts have turned to the ‘‘common 

practice of consulting dictionary 

definitions to clarify their ordinary 

meaning.’’ United States v. TRW Rifle 

7.62X51mm Caliber, One Model 14 

Serial 593006, 447 F.3d 686, 689 (9th 

Cir. 2006) (internal quotation marks 

omitted). The ‘‘plain and unambiguous 

ordinary meaning of ‘readily’ may be 

defined by a temporal component . . . 

or a component related to a manner or 

methodology’’ and ‘‘must not be 

construed as an abstract phrase, but 

rather its contours should be 

determined in . . . context.’’ Id. at 690 

(internal quotation marks omitted). 

The Department disagrees with 

commenters that the explanation in the 

proposed rule of how ATF would 

determine which portion of a ‘‘firearm’’ 

is the frame or receiver in a split or 

modular weapon was unconstitutionally 

vague. ATF has applied that criteria for 

many decades as to split or modular 

weapons. Nonetheless, because the 

Department agrees with commenters 

that the definition of ‘‘firearm’’ in 18 

U.S.C. 921(a)(3)(B) is best read to mean 

a single part of a weapon or device as 

being ‘‘the’’ frame or receiver, the 

Department provides under the 

definition of ‘‘frame or receiver’’ new 

distinct sub-definitions for frames with 

respect to handguns; receivers with 

respect to rifles, shotguns, and projectile 

weapons other than handguns; and 

frames or receivers for firearm mufflers 

and silencers. The final rule does not 

adopt the proposed supplement entitled 

‘‘Split or Modular Frame or Receiver.’’ 

The final rule also provides illustrative 

examples of ATF’s prior classifications 

that are grandfathered, and examples of 

when a partially complete, 

disassembled, or nonfunctional frame or 

receiver is considered readily 

completed, assembled, restored, or 

otherwise converted to a functional 

state. See Parker v. Levy, 417 U.S. 733, 

754 (1974) (examples provided 

‘‘considerable specificity’’ of ‘‘the 

conduct which they cover’’). With these 

clarifications in the final rule, licensees, 

and the public, can make their own 

determinations to identify the frame or 

receiver of a weapon without an ATF 

classification. 

These definitions use the terms with 

their ordinary meanings and in context, 

see TRW Rifle, 447 F.3d at 689, 690, and 

are sufficiently clear to ‘‘give the person 

of ordinary intelligence a reasonable 

opportunity to know what is 

prohibited,’’ Village of Hoffman Estates 

v. Flipside, Hoffman Estates, Inc., 455 

U.S. 489, 498 (1982) (citing Grayned, 

408 U.S. at 108–09). Absolute certainty 

is not required. See United States v. 

Hosford, 843 F.3d 161, 171 (4th Cir. 

2016) (laws ‘‘necessarily have some 

ambiguity, as no standard can be 

distilled to a purely objective, 

completely predictable standard.’’); 

Draper v. Healey, 827 F.3d 1, 4 (1st Cir. 

2016) (‘‘if due process demanded [a] 

how-to guide, swaths of the United 

States Code, to say nothing of state 

statute books, would be vulnerable’’); 

United States v. Lachman, 387 F.3d 42, 

56 (1st Cir. 2004) (‘‘The mere fact that 

a statute or regulation requires 

interpretation does not render it 

unconstitutionally vague.’’); Kolbe v. 

O’Malley, 42 F. Supp. 3d 768, 800 (D. 

Md. 2014) (A ‘‘statute is not 

impermissibly vague simply because it 

does not spell out every possible factual 

scenario with celestial precision.’’ 

(internal quotation marks omitted)).80

Commenters cite to Christopher v. 

SmithKline Beecham Corp., 567 U.S. 

142, 155–56 (2012), but that case did not 

involve constitutional vagueness claims 

at all. It instead addressed when Auer 

deference is due to an agency’s 

interpretation of its own ambiguous 

regulations. Id. Here, by contrast, ATF is 

promulgating new regulations 

implementing the NFA and GCA 

through a formal rulemaking procedure. 

And as explained above, the terms 

employed in this rule comport with 

ordinary usage and the case law 

interpreting those terms. 

f. Violates the Fifth Amendment— 

Unconstitutional Taking 

Comments Received 

Commenters opposed to the NRPM 

asserted that the regulations would 

result in an unconstitutional taking 

under the Fifth Amendment. 

Commenters claimed that the 

government is obligated to compensate 

people who lost money based on the 

agency’s misrepresentations. One 

commenter argued that an 

unconstitutional taking would occur if 

FFLs are forced to either mark PMFs 

currently in their possession in 

accordance with the proposed rule, 

destroy the PMFs, or ‘‘voluntarily’’ turn 

the PMFs over to law enforcement 

officials within 60 days of the effective 

date of the final rule. The commenter 

claimed that the ‘‘voluntary’’ surrender 

to law enforcement officials is a 

government taking of personal property. 

The commenter relied on Loretto v. 

Teleprompter Manhattan CATV Corp., 

458 U.S. 419 (1982), where the Supreme 

Court explained that, with regard to the 

factual inquiry involved in a takings 

claim under Penn Central 

Transportation Co. v. New York City, 

438 U.S. 104 (1978), a ‘‘governmental 

action’’ that results in ‘‘a permanent 

physical occupation of property’’ 

represents ‘‘a taking to the extent of the 

occupation, without regard to whether 

the action achieves an important public 

benefit or has only minimal economic 

impact on the owner.’’ 458 U.S. at 434– 


jspears on DSK121TN23PROD with RULES2
24680 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

35. The commenter claimed that absent 

specific asset forfeiture instructions 

directing Federal law enforcement 

agencies to destroy any PMFs 

‘‘voluntarily’’ turned in by FFLs, the 

proposed rule fails to set forth any 

safeguards that prevent Federal law 

enforcement agencies from repurposing 

the PMFs for their own use and 

therefore effectuates a regulatory taking 

of private property without just 

compensation. 

Department Response 

The Department disagrees that the 

regulation constitutes a taking, and 

further disagrees that it results in a 

compensable taking. In order to remain 

in compliance, FFLs are not required to 

destroy unmarked PMFs or surrender 

them to ATF. They can mark them, or 

have them marked, as required by 

regulation, which does not require any 

transfer or loss of property. However, if 

an FFL chooses to destroy a PMF, that 

is not compensable. Moreover, the 

Federal Circuit has recognized that, 

under Supreme Court precedent, there 

are certain exercises ‘‘of the police 

power that ha[ve] repeatedly been 

treated as legitimate even in the absence 

of compensation to the owners of the 

. . . property.’’ Acadia Tech., Inc. v. 

United States, 458 F.3d 1327, 1332–33 

(Fed. Cir. 2006). As the Supreme Court 

articulated the doctrine, ‘‘[a] prohibition 

simply upon the use of property for 

purposes that are declared, by valid 

legislation, to be injurious to the health, 

morals, or safety of the community, 

cannot, in any just sense, be deemed a 

taking or an appropriation of property 

for the public benefit.’’ Mugler v. 

Kansas, 123 U.S. 623, 668–69 (1887); 

see Acadia Tech., 458 F.3d at 1333. 

The Federal Circuit has applied this 

precedent in situations where Federal 

law enforcement has acted pursuant to 

seizure statutes, and criminal laws, to 

find that no compensable taking exists. 

AmeriSource Corp. v. United States, 525 

F.3d 1149, 1154 (Fed. Cir. 2008); Acadia 

Tech., 458 F.3d at 1333. In doing so, the 

court emphasized that ‘‘[p]roperty 

seized and retained pursuant to the 

police power is not taken for a ‘public 

use’ in the context of the Takings 

Clause.’’ AmeriSource, 525 F.3d at 1153. 

In these decisions, the Federal Circuit 

found no taking occurs irrespective of 

whether the government had physically 

seized the property or rendered it 

worthless. Id. at 1153–54; Acadia, 458 

F.3d at 1333. 

The Federal Circuit and the Court of 

Federal Claims have also made clear 

that these principles apply with full 

force in analyzing the impact of firearms 

regulations promulgated pursuant to the 

Federal power to regulate commerce. In 

Mitchell Arms, Inc. v. United States, 7 

F.3d 212 (Fed. Cir. 1993), the Federal 

Circuit rejected a takings claim brought 

by a firearms business whose permits to 

import semiautomatic rifles were 

revoked. Similarly, in Akins v. United 

States, 82 Fed. Cl. 619 (2008), the Court 

of Federal Claims rejected takings 

claims, including a per se takings claim, 

after ATF reconsidered its prior 

classification decisions regarding the 

Akins Accelerator. The Court explained 

that ‘‘[p]roperty seized and retained 

pursuant to the police power is not 

taken for a ‘public use’ in the context of 

the Takings Clause.’’ Id. at 622 (quoting 

AmeriSource, 525 F.3d at 1153). And, 

citing Mitchell Arms, the Akins Court 

also found that the plaintiff was fully 

aware of the ‘‘potential for federal 

regulation of his invention’’ and his 

‘‘expectation interest’’ was ‘‘not a 

property interest protected by the Fifth 

Amendment.’’ Id. at 624; see also 

Maryland Shall Issue v. Hogan, 353 F. 

Supp. 3d 400, 408–17 (D. Md. 2018) 

(rejecting takings claim arising from 

State ban on bump stocks), aff’d, 963 

F.3d 356 (4th Cir. 2020); cf. McCutchen 

v. United States, 14 F.4th 1355, 1364– 

65 (Fed. Cir. 2021) (rejecting takings 

claim on the ‘‘related’’ ground that no 

taking occurs where the government 

‘‘asserts a pre-existing limitation upon 

the [property] owner’s title’’ to require 

destruction of a banned weapon 

(internal quotation marks omitted)). 

Even under a takings analysis, the 

regulation would be analyzed under 

Penn Central, and the regulation would 

be upheld. Under Penn Central, a court 

considers: (1) The economic impact of 

the regulation on the claimant, (2) its 

interference with investment-based 

expectations, and (3) the character of the 

governmental action. 438 U.S. at 124. 

No taking exists under Penn Central. 

A restriction ‘‘directed at the protection 

of public health and safety . . . is the 

type of regulation in which the private 

interest has traditionally been most 

confined and governments are given the 

greatest leeway to act without the need 

to compensate those affected by their 

actions.’’ Rose Acre Farms, Inc. v. 

United States, 559 F.3d 1260, 1281 (Fed. 

Cir. 2009). A plaintiff’s ‘‘reasonable 

investment-backed expectations are 

greatly reduced in a highly regulated 

field,’’ Branch v. United States, 69 F.3d 

1571, 1581 (Fed. Cir. 1995), such as the 

firearms industry. And as the Supreme 

Court has made clear, ‘‘an owner of 

personal property ‘ought to be aware of 

the possibility that new regulation 

might even render his property 

economically worthless.’ ’’ See Lucas v. 

S.C. Costal Council, 505 U.S. 1003, 

1027–28 (1992). As for the economic 

impact, licensees do not have to 

abandon or destroy anything; they need 

only mark PMFs with serial numbers as 

required by the GCA if they choose to 

take those items into inventory. 

Commenters’ citation to Loretto is 

inapplicable. The Loretto decision states 

nothing about regulating the possession 

of inherently dangerous personal 

property. Instead, Loretto involved a 

challenge to a state law requiring a 

landlord to install cable television 

facilities on the landlord’s building. 458 

U.S. at 421. The Court found a per se 

physical taking based upon the physical 

invasion of the landlord’s real property. 

Id. at 426. Here, in contrast, the 

government has not required anyone to 

transfer title of anything to the 

government and has not physically 

invaded anyone’s property. Moreover, 

even the physical seizure of highly 

regulated goods pursuant to the 

government’s police power has never 

been thought to constitute a per se 

taking. See Kam-Almaz v. United States, 

682 F.3d 1364, 1372 (Fed. Cir. 2012); 

AmeriSource, 525 F.3d at 1153; Acadia 

Tech., 458 F.3d at 1332–33. 

To the extent commenters are arguing 

that a categorical regulatory taking 

under Lucas has occurred, they are 

incorrect. First, the Lucas test does not 

apply to valid exercises of the 

government’s police power in enforcing 

the criminal laws. That is the case even 

where personal property may become 

worthless as a result of the government’s 

action, which is not the case here. See 

AmeriSource, 525 F.3d at 1154; Akins, 

82 Fed. Cl. at 621–23. Lucas also does 

not apply to the regulation of personal 

property of the type involved here. The 

Supreme Court has never held that even 

a complete ban on possessing dangerous 

personal property constitutes a per se 

taking under Lucas (or any per se test). 

The Supreme Court has explained that 

the categorical takings analysis applies 

only in the ‘‘relatively rare’’ and 

‘‘extraordinary circumstance when no 

productive or economically beneficial 

use of land is permitted.’’ Lucas, 505 

U.S. at 1017–18. Although the Court has 

had reason to consider Lucas on 

multiple occasions, it has never applied 

the rule to any type of property rights 

other than real property. See 

McCutchen, 14 F.4th at 1371–72 (‘‘The 

cases in which the Supreme Court has 

applied Lucas’s total takings rule have 

involved real property, and Circuit 

Courts have not reached a clear 

consensus on how broadly to apply 

Lucas’s per se rule.’’) (Wallach, J., 

concurring in result). 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24681 

81For example, Blackhawk Manufacturing Group 

objected to the inclusion of its website address, and 

claimed it was being targeted because ‘‘ATF seeks 

to put [it] out of business.’’ This is inaccurate. If 

Blackhawk Manufacturing Group is interested in 

engaging in the business of manufacturing firearms, 

it need only apply for a license like other 

commercial firearms manufacturers. 

g. Violates the Fifth Amendment—Equal 

Protection Clause 

Comments Received 

Several commenters claimed that the 

proposed rule violates the Equal 

Protection Clause by targeting the 

products of certain law-abiding 

businesses, including by naming 

particular companies.81

Department Response 

The Department disagrees that the 

proposed rule violates the Equal 

Protection Clause. If a ‘‘classification 

‘impermissibly interferes with the 

exercise of a fundamental right or 

operates to the peculiar advantage of a 

suspect class,’ [a court will] subject the 

classification to strict scrutiny. 

Otherwise, [courts] will uphold the 

classification if it is ‘rationally related to 

a legitimate state interest.’ ’’ Mance v. 

Sessions, 896 F.3d 699, 711 (5th Cir. 

2018) (citing NRA v. ATF, 700 F.3d 185, 

211–12 (5th Cir. 2012)). There is no 

fundamental right to be engaged in the 

business of manufacturing firearms or to 

possess unserialized firearms. See 

Defense Distributed, 121 F. Supp. 3d at 

699; Marzzarella, 614 F.3d at 93. Nor are 

firearms manufacturers a suspect class. 

Rational basis review therefore applies. 

Under rational basis review, a 

classification ‘‘is accorded a strong 

presumption of validity.’’ Heller v. Doe 

by Doe, 509 U.S. 312, 319 (1993). ‘‘The 

firearm regulatory scheme . . . is 

consonant with the concept of equal 

protection embodied in the Due Process 

Clause of the Fifth Amendment if there 

is some rational basis for the statutory 

distinctions made . . . or they have 

some relevance to the purpose for which 

the classification is made.’’ Lewis v. 

United States, 445 U.S. 55, 65 (1980) 

(internal quotation marks omitted). 

There is clearly a rational basis for 

requiring those engaged in the business 

of manufacturing firearms to be licensed 

and serialize their firearms. The 

‘‘principal purpose’’ of the GCA is to 

curb crime by keeping ‘‘firearms out of 

the hands of those not legally entitled to 

possess them.’’ Huddleston v. United 

States, 415 U.S. 814, 824 (1974) 

(internal quotation marks omitted). As a 

result, ‘‘[c]ommerce in firearms is 

channeled through federally licensed 

importers, manufacturers, and dealers in 

an attempt to halt mail-order and 

interstate consumer traffic in these 

weapons.’’ Id.; see also United States v. 

Biswell, 406 U.S. 311, 315 (1972) 

(‘‘[C]lose scrutiny’’ of ‘‘interstate traffic 

in firearms’’ is ‘‘undeniably of central 

importance to federal efforts to prevent 

violent crime and to assist the States in 

regulating the firearms traffic within 

their borders.’’); id. at 315–16 (‘‘Federal 

regulation’’ of the traffic in firearms 

‘‘assures that weapons are distributed 

through regular channels and in a 

traceable manner.’’); United States v. 

Hosford, 82 F. Supp. 3d 660, 667 (D. 

Md. 2015) (prohibiting engaging in the 

business of firearms without a license 

‘‘ensures that significant commercial 

traffic in firearms will be conducted 

only by parties licensed by the federal 

government’’); id. (‘‘Nor is the licensing 

requirement onerous.’’); Marzzarella, 

614 F.3d at 100 (requiring serial 

numbers not only allows for the ‘‘tracing 

of the chain of custody of firearms 

involved in crimes,’’ but also ‘‘provides 

agencies with vital criminology 

statistics,’’ ‘‘as well as allowing for the 

identification of individual dealers 

involved in the trafficking of firearms 

and the matching of ballistics date with 

recovered firearms’’); United States v. 

Adams, 305 F.3d 30, 34 (1st Cir. 2002) 

(‘‘[A]nyone can see what Congress was 

getting at[;]’’ the serial number is the 

‘‘principal means of tracing origin and 

transfers in ownership.’’) And, as stated 

above, public safety and crime 

prevention are compelling governmental 

interests. 

2. Statutory Authority Concerns 

a. Lack of Delegated Authority To 

Promulgate the Rule 

Comments Received 

A majority of commenters opposed to 

the NPRM argued that ATF is exceeding 

its authority by promulgating the rule 

and that it is the job of Congress to 

change the laws and the job of Federal 

agencies to enforce them. Because the 

NPRM explained that the agency is 

changing its regulations in response to 

the manner in which courts have ruled 

on the AR–15-type firearm receiver, 

commenters stated that it is Congress’s 

role to amend the law if the law has 

become out of date and that this power 

cannot be usurped by a non-legislative 

governmental entity. 

Other commenters argued that ATF’s 

authority to enact regulations is 

constrained under 18 U.S.C. 926. They 

pointed to the Firearms Owners’ 

Protection Act of 1986 (‘‘FOPA’’) and its 

accompanying legislative history, when 

Congress amended section 926 by 

deleting the discretionary language that 

allowed the Secretary to ‘‘prescribe such 

rules and regulations as he deems 

reasonably necessary to carry out the 

provisions of this chapter.’’ Commenters 

stated the prior language was a broader 

standard and it was amended to the 

current language, which only allows the 

Attorney General to ‘‘prescribe only 

such rules and regulations as necessary 

to carry out the provisions of this 

chapter.’’ Further, the commenters 

stated that none of the examples 

provided in section 926(a) ‘‘indicate[s] 

any intention of Congress to delegate to 

the ATF the power to define the items 

regulated under the GCA . . . in a 

manner that expands or contracts the 

scope of the GCA. Rather, [the] 

examples reinforce Congressional [sic] 

to severely limit ATF’s authority to 

those required to carry out the 

administration of the provisions 

contained within the GCA.’’ 

Other commenters argued that ATF 

lacks the authority to act because it is 

in violation of the non-delegation 

doctrine, which asks ‘‘whether Congress 

has supplied an intelligible principle to 

guide the delegee’s use of discretion.’’ 

Gundy v. United States, 139 S. Ct. 2116, 

2123 (2019). Specifically, they argued 

that the GCA contains no intelligible 

principle to guide ATF’s rulemaking 

authority nor provides any standards for 

the Department or ATF to redefine 

statutory definitions. Instead, the 

commenters asserted, the Attorney 

General’s rulemaking authority is 

limited to 18 U.S.C. 926(a). Another 

commenter wrote that ‘‘nothing grants 

ATF or any other agency the discretion 

to modify this command’’ in the GCA 

that all firearms must bear a serial 

number although ATF has the ability to 

provide the practical details of how the 

marking is to be done. However, the 

commenter argued the proposed rule 

grants ATF far too much discretion in 

deciding which firearms it will regulate 

and would open ‘‘a floodgate of 

policymaking discretion that the GCA 

does not and cannot grant to it.’’ Many 

other commenters raised specific 

arguments that ATF’s newly proposed 

and revised definitions, as well as other 

proposed marking and recordkeeping 

requirements on FFLs, are contrary to 

the GCA. Those separate specific 

arguments are explained in further 

detail below. See Sections IV.B.2.b–f of 

this preamble. 

Department Response 

The Department disagrees that ATF 

lacks the delegated legal authority to 

promulgate rules that are necessary to 

implement the GCA and the NFA, 

including the definitions of ‘‘frame or 

receiver’’ promulgated by the 

predecessor agency to ATF. The 


jspears on DSK121TN23PROD with RULES2
24682 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

82 In this regard, the GCA and NFA include both 

general and specific delegations of rulemaking 

authority. Compare 18 U.S.C. 926(a) (‘‘The Attorney 

General may prescribe only such rules and 

regulations as are necessary to carry out the 

provisions of this chapter . . . .’’); H.R. Rep. No. 

90–1577, at 18 (June 21, 1968) (‘‘Section 926. Rules 

and regulations. This section grants rulemaking 

authority to the Secretary . . . .’’); S. Rep. No. 90– 

1501, at 39 (Sept. 6, 1968) (same), and 26 U.S.C. 

7805(a) (‘‘the [Attorney General] shall prescribe all 

needful rules and regulations for the enforcement 

of this title, including all rules and regulations as 

may be necessary by reason of any alteration of law 

in relation to internal revenue.’’), with 18 U.S.C. 

921(a)(13) (‘‘The term ‘collector’ means any person 

who acquires, holds, or disposes of firearms as 

curios or relics, as the Attorney General shall by 

regulation define . . . .’’); id. sec. 923(g)(1)(A) 

(‘‘Each licensed importer, licensed manufacturer, 

and licensed dealer shall maintain such records of 

importation, production, shipment, receipt, sale, or 

other disposition of firearms at his place of business 

for such period, and in such form, as the Attorney 

General may by regulations prescribe.’’); id. sec. 

923(g)(2) (‘‘Each licensed collector shall maintain in 

a bound volume the nature of which the Attorney 

General may by regulations prescribe, records of the 

receipt, sale, or other disposition of firearms.’’); id. 

sec. 923(i) (‘‘Licensed importers and licensed 

manufacturers shall identify by means of a serial 

number engraved or cast on the receiver or frame 

of the weapon, in such manner as the Attorney 

General shall by regulations prescribe, each firearm 

imported or manufactured by such importer or 

manufacturer.’’); 26 U.S.C. 5841(c) (‘‘Each 

manufacturer shall notify the Secretary of the 

manufacture of a firearm in such manner as may by 

regulations be prescribed . . . .’’); id. sec. 5842(a) 

(‘‘Each manufacturer and importer and anyone 

making a firearm shall identify each firearm, other 

than a destructive device, manufactured, imported, 

or made by a serial number which may not be 

readily removed, obliterated, or altered, the name 

of the manufacturer, importer, or maker, and such 

other identification as the [Attorney General] may 

by regulations prescribe.’’); and id. sec. 5843 

(‘‘Importers, manufacturers, and dealers shall keep 

such records of, and render such returns in relation 

to, the importation, manufacture, making, receipt, 

and sale, or other disposition, of firearms as the 

[Attorney General] may by regulations prescribe.’’). 

83Cf. Cargill v. Barr, 502 F. Supp. 3d 1163, 1188 

(W.D. Tex. 2020), aff’d on other grounds, 20 F.4th 

1004, 1014 (5th Cir. 2021) (‘‘The delegations of 

authority supporting the Final Rule [defining 

‘‘machinegun’’] also do not violate non-delegation 

principles because 18 U.S.C. 926(a) only permits 

the Attorney General to ‘prescribe such rules and 

regulations as are necessary to carry out the 

provisions of [the GCA]’ and 26 U.S.C. 7805 

provides similar authority for ‘all needful rules and 

regulations for the enforcement of [the NFA].’ 18 

U.S.C. 926(a); 26 U.S.C. 7805(a). Given that the 

Supreme Court has ‘over and over upheld even very 

broad delegations,’ like ones requiring an agency 

merely ‘to regulate in the ‘‘public interest,’ ’’ the 

delegations underlying the Final Rule pass the 

‘intelligible principle’ test.’’). 

Department’s and ATF’s legal authority 

includes the authority to promulgate 

regulations and rules implementing and 

interpreting the GCA and NFA, to 

specify the information and period by 

which firearms are required to be 

marked pursuant to the GCA and NFA, 

and to specify the precise period and 

form in which Federal firearm licensee 

records required by the GCA and NFA 

are maintained.82 Congress and the 

Attorney General have delegated the 

responsibility for administering and 

enforcing the GCA and NFA to the 

Director of ATF, subject to the direction 

of the Attorney General and the Deputy 

Attorney General. See 26 U.S.C. 

7801(a)(2); 28 U.S.C. 599A(b)(1), (c)(1); 

28 CFR 0.130(a)(1)–(2); T.D. Order No. 

221(2)(a), (d), 37 FR 11696–97 (June 10, 

1972). ‘‘Because § 926 authorizes the 

[Attorney General] to promulgate those 

regulations which are ‘necessary,’ it 

almost inevitably confers some measure 

of discretion to determine what 

regulations are in fact ‘necessary.’ ’’ 

Nat’l Rifle Ass’n v. Brady, 914 F.2d 475, 

479 (4th Cir. 1990). And courts have 

long recognized that regulatory agencies 

do not establish rules to last forever. 

‘‘They are neither required nor 

supposed to regulate the present and the 

future within the inflexible limits of 

yesterday.’’ Am. Trucking Ass’n v. 

Atchison, Topeka, and Santa Fe Ry. Co, 

387 U.S. 397, 416 (1967). 

As to comments asserting that the 

GCA’s various delegations of 

rulemaking authority to the Attorney 

General and ATF violate the nondelegation doctrine, the Supreme Court 

has consistently rejected similar 

arguments with respect to public safety 

statutes. See Whitman v. American 

Trucking Ass’ns, 531 U.S. 457, 474 

(2001) (‘‘[W]e have found an 

‘‘intelligible principle’’ in various 

statutes authorizing regulation in the 

‘public interest.’ ’’ (collecting cases)). 

The definitions and requirements 

established by this rule are all guided by 

the intelligible principles set forth in the 

GCA governing the manufacture, 

importation, dealing, and collecting of 

firearms, including licensing, marking, 

recordkeeping, background checks, and 

crime gun tracing.83

b. Lack of Authority To Regulate 

Multiple Parts as ‘‘Frames or Receivers’’ 

Comments Received 

A large number of commenters 

objected to the proposed definition of 

‘‘firearm frame or receiver’’ and, in 

particular, the supplemental definition 

of ‘‘split or modular frame or receiver.’’ 

Commenters stated that the statute is 

clear that a firearm has only one, 

singular frame or receiver and that 

Congress (as ATF pointed out in its 

NPRM) elected not to regulate all 

firearms parts when it repealed the FFA 

and revised the definition of ‘‘firearm’’ 

in 1968 when passing the GCA. 

According to these commenters, 

contrary to the intent of Congress, the 

NPRM’s definition of frame or receiver 

would return to regulating individual 

firearm parts by allowing several parts 

to be considered the frame or receiver. 

Several commenters stated that 

Congress knew how to distinguish 

between a whole and parts of a whole. 

For example, Congress included both 

the whole and any one of the individual 

constituent parts in the definition of a 

silencer or a muffler, which is defined 

in 18 U.S.C. 921(a)(24) as ‘‘any 

combination or parts . . . and any part 

intended for use in such assembly or 

fabrication,’’ and a ‘‘handgun’’ is 

defined in 18 U.S.C. 921(a)(29) as ‘‘any 

combination of parts . . . .’’ If Congress 

had intended multiple parts of other 

firearms to be ‘‘firearms,’’ it could have 

used similar language. Moreover, 

Congress has amended the GCA several 

times without redefining the terms at 

issue. 

At least one commenter rejected 

ATF’s reliance on the series of tax cases 

listed in the NPRM as authority for 

interpreting statutory definitions to 

avoid clear error in applying the law. 

The commenter stated that the 

Department is not interpreting clear 

error, but instead is rewriting the law. 

Some commenters also highlighted NizChavez v. Garland, 141 S. Ct. 1474 

(2021), a recent Supreme Court case that 

examined another Federal statute with a 

singular article before a defined term. In 

Niz-Chavez, the Court evaluated 

whether an immigration statute’s 

requirement to send ‘‘a notice’’ with 

certain information was met when the 

government sent multiple notices, each 

of which did not contain all of the 

information required by the statute. The 

Court applied a plain reading of the text 

and said the government must send a 

single notice. Id. at 1486. In holding that 

a singular usage controlled, the Court in 

Niz-Chavez rejected the government’s 

attempt to use the Dictionary Act as a 

way to pluralize the otherwise singular 

text of the term, stating ‘‘[t]he Dictionary 

Act does not transform every use of the 

singular ‘a’ into the plural ‘several.’ ’’ Id. 

at 1482. 

Many other commenters disagreed 

with ATF’s claim that single frames or 

receivers were more prevalent for 

civilian use over split or multi-piece 

receivers at the time of the GCA’s 

enactment and issuance of the original 

implementing regulations. One 

commenter provided copies of historical 

materials on firearms, including from 

the Department of Defense, to support 

his assertion that Members of Congress 

in 1967, many of whom had served in 

World War II, would have been 

personally familiar with ‘‘new-fangled’’ 

rifles that had an upper and a lower 

receiver. For this reason, the commenter 

asserted that it is, therefore, not possible 

for ATF to argue that Congress did not 

know there were rifles with upper and 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24683 

84The Dictionary Act recognizes that ‘‘[i]n 

determining the meaning of any Act of Congress, 

unless the context indicates otherwise, words 

importing the singular include and apply to several 

persons, parties, and things.’’ 1 U.S.C. 1; see also 

Niz-Chavez, 141 S. Ct. at 1482 (the Dictionary Act 

tells us that a statute using the singular can apply 

to multiple persons, parties, or things); Barr v. 

United States, 324 U.S. 83, 91 (1945) (citing 1 

U.S.C. 1 as authority for construing the statutory 

term ‘‘buying rate’’ to include more than one buying 

rate); Day v. Sec. of Health & Human Services, 129 

Fed. Cl. 450, 452 (2016) (‘‘The mere use of terms 

in the singular, of course, hardly provides the 

context for escaping the ambit of the Dictionary Act 

rule regarding the use of the singular.’’); 

Georgetown Univ. Hospital v. Sullivan, 934 F.2d 

1280, 1283–84 (D.D.C. 1991) (use of definite article 

‘‘the’’ with the singular word ‘‘amount’’ did not 

preclude the possibility there may be more than one 

‘‘amount’’). 

85The Department recognizes that ‘‘combinations 

of parts’’ was added to the definition of ‘‘handgun’’ 

in the GCA by section 102 of the Brady Handgun 

Violence Protection Act, Public Law 103–159 

(1993). 

86Cf. United States v. Morales, 280 F. Supp. 2d 

262, 273 (S.D.N.Y. 2003) (‘‘[T]he different parts 

represented in Exhibit J to the Becker Affirmation 

include both the ‘‘frame’’ and the ‘‘receiver’’ of a 

Tec–9 pistol, and are therefore explicitly covered 

under the language of 18 U.S.C. 921(a)(3)(B).’’). 

87See Juvenile Delinquency: Investigation of 

Juvenile Delinquency in the United States: Hearing 

before the S. Comm. on the Judiciary, 88th Cong. 

(1963) (technical memorandum of Internal Revenue 

Service) (‘‘The present definition [of ‘‘firearm’’] 

includes any ‘part’ of a weapon within the term. It 

has been found that it is impracticable, if not 

impossible, to treat all parts of a firearm as if they 

were a weapon capable of firing. This is particularly 

true with respect to recordkeeping provisions since 

small parts are not easily identified by a serial 

number. Accordingly, there are no objections to 

modifying the definition so that all parts, other than 

frames or receivers, are eliminated. It should be 

noted that this amendment to the definition of 

‘firearm’ eliminates all parts of a weapon, other 

than receivers and frames, from the provisions of 

the act.’’). 

88However, the Department disagrees with 

commenters who suggested that the AR–15 rifle was 

in common civilian (i.e., non-military or law 

enforcement) use in the United States when ATF’s 

predecessor agency originally promulgated its 

regulatory definitions of ‘‘frame or receiver’’ in 1968 

(Part 478) and 1971 (Part 479). While millions of 

AR–15s/M–16s existed at the time ATF 

promulgated the definitions, the vast majority were 

Continued 

lower receivers when re-defining 

‘‘firearm’’ to include ‘‘the frame or 

receiver’’ instead of ‘‘any part or parts 

of such weapon.’’ Other commenters 

also pointed to specific models designed 

for the military that found their way 

into common use after World War I, 

including the 1911 pistol and the 

Thompson gun. 

One commenter, who is a 

manufacturer, also cited a 1971 

Treasury Memorandum on the M16 

receiver to show that when ATF was 

part of the Department of the Treasury, 

the agency had considered split or 

multi-piece receiver firearms during the 

initial rulemaking process but felt it 

impracticable to do so. The author of the 

1971 memorandum stated the ‘‘M–16 

receiver is fabricated in two parts . . . . 

Both parts were necessary to function as 

a ‘frame or receiver . . . .’ I can see 

some difficulty in trying to make cases 

against persons possessing only the 

lower part of the receiver, but insofar as 

licensing, serial numbering, and special 

occupational tax requirements are 

concerned, I feel that [serializing the 

lower] is the only practical solution.’’ 

See CC: ATF–12,736, Subject: M16 

Receivers, Internal Revenue Service, 

Department of the Treasury (March 1, 

1971). 

Department Response 

Although the Department disagrees 

with numerous commenters who claim 

that the term ‘‘frame or receiver’’ in 18 

U.S.C. 921(a)(3)(B) must be read to mean 

that a firearm may not have more than 

one frame or receiver, the Department 

has decided to alter the proposed 

definition in this final rule in response 

to comments.84 The Department agrees 

with commenters that section 

921(a)(3)(B) must be read in context, 

and recognizes that the Supreme Court 

in Niz-Chavez instructs courts to 

exhaust all textual and structural clues 

bearing on the meaning of a statutory 

term. 141 S. Ct. at 1480. The statutory 

term in question is ‘‘the frame or 

receiver of any such weapon’’ (emphasis 

added). Unfortunately, here, there are 

contextual and structural clues that 

point in different directions. On one 

hand, ‘‘the frame or receiver of any such 

weapon’’ refers to a weapon in section 

921(a)(3)(A), and that definition uses a 

singular article when referring to more 

than one firearm design. For example, 

section 921(a)(3)(A) states that a 

‘‘firearm’’ includes ‘‘any weapon . . . 

which will or is designed to . . . expel 

a projectile by the action of an 

explosive’’ (emphasis added). By using 

the singular term ‘‘a,’’ Congress clearly 

did not mean to regulate only those 

weapons that will or are designed to 

expel only a single projectile. Almost all 

firearms are designed to expel more 

than one projectile after the first, and 

numerous firearm designs, such as 

shotguns and machineguns, will expel 

multiple projectiles at the same time. 

Moreover, as one commenter pointed 

out, one major design of a ‘‘firearm’’ 

under 18 U.S.C. 921(a)(3)(A) is a 

handgun, and the definition of 

‘‘handgun’’ in 18 U.S.C. 921(a)(29)(B) 

includes ‘‘any combination of parts from 

which a [handgun] can be 

assembled.’’ 85 Thus, it is possible that 

the term ‘‘frame,’’ for example, could be 

referring to multiple frames within a 

handgun, or both a frame and a receiver 

in a split handgun design.86

On the other hand, the marking 

requirement for manufacturers and 

importers, 18 U.S.C. 923(i), refers to 

identifying ‘‘a’’ serial number on ‘‘the’’ 

receiver or frame of the weapon. And 

the GCA similarly amended the 

definition of ‘‘machinegun’’ in the NFA 

at 26 U.S.C. 5845(b) to refer to a singular 

component when including ‘‘the’’ frame 

or receiver of any such weapon. The 

Department agrees with numerous 

commenters that the context of the 

singular terms ‘‘frame’’ and ‘‘receiver’’ 

in these provisions suggests that a 

firearm only has one frame or receiver. 

This reading is more consistent with the 

GCA’s legislative history explaining that 

Congress found it impractical to treat 

each small part of a firearm as if it were 

a weapon capable of firing.87

After carefully considering the 

numerous comments submitted on this 

issue, the Department agrees that 

reading the GCA to encompass only one 

single part of a given weapon would 

greatly reduce the possibility that a 

modified weapon might have more than 

one serial number. Having more than 

one serial number per firearm would 

make it more difficult and costly for 

licensees to mark firearms and maintain 

associated records, and for law 

enforcement to trace firearms used in 

crime. Because the NPRM contemplated 

the possibility that a given firearm 

under the proposed rule would have 

more than one frame or receiver with 

different serial numbers, the Department 

is responding to the concerns of those 

comments by focusing on three subsets 

of the proposed definition of ‘‘frame or 

receiver.’’ Specifically, the final rule 

defines that term to mean a housing or 

structure for a single fire control 

component—‘‘frame’’ for handguns and 

variants thereof; ‘‘receiver’’ for rifles, 

shotguns, and projectile weapons other 

than handguns and variants thereof; and 

‘‘frame’’ or ‘‘receiver’’ for firearm 

muffler or silencer devices. 

Finally, to ease the transition to the 

new definitions and marking 

requirements, the Department will 

grandfather existing split frame or 

receiver designs previously classified by 

ATF as the firearm ‘‘frame or receiver’’ 

prior to the issuance of this rule (except 

for certain partially complete, 

disassembled, or nonfunctional frames 

or receivers, to include weapon or frame 

or receiver parts kits). For example, the 

lower receiver of the AR–15-type rifle 

and variants thereof are expressly 

included within the new definition of 

‘‘receiver’’ and may be marked 

according to the rules that existed before 

this rule.88


jspears on DSK121TN23PROD with RULES2
24684 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

manufactured for military use. See Internal Colt 

Memorandum from B. Northrop, Feb. 2, 1973, p. 2 

(noting that there were 2,752,812 military versus 

25,774 civilian (‘‘Sporters’’) serialization of AR–15/ 

M–16 rifles then manufactured). 

89See, e.g., United States v. Annis, 446 F.3d 852, 

857 (8th Cir. 2006) (partially disassembled rifle that 

could easily be made operational was a firearm 

under section 921(a)(3)(A)); United States v. Ryles, 

988 F.2d 13, 16 (5th Cir. 1993) (disassembled 

shotgun was a firearm because it could have been 

readily converted to an operable firearm); United 

States v. Theodoropoulos, 866 F.2d 587, 595 n.3 (3d 

Cir. 1989) (machine pistol that was disassembled 

that could easily be made operable); Enamorado v. 

United States, No. C16–30290–MWB, 2017 WL 

2588428, at *6 (N.D. Iowa June 14, 2017) 

(disassembled .45 caliber handgun that could easily 

be reassembled); United States v. Morales, 280 F. 

Supp. 2d 262, 272–73 (S.D.N.Y. 2003) (partially 

disassembled Tec-9 pistol that could be assembled 

within short period of time could readily be 

converted to expel a projectile); United States v. 

Randolph, No. 02 CR. 850–01 (RWS), 2003 WL 

1461610, at *2 (S.D.N.Y. Mar. 20, 2003) (gun 

consisting of ‘‘disassembled parts with no 

ammunition, no magazine, and a broken firing pin, 

making it incapable of being fired without 

replacement or repair’’ was a ‘‘firearm’’ because it 

could be readily converted to expel a projectile and 

included the frame or receiver of any such weapon). 

90See, e.g., United States v. Wick, 697 F. App’x 

507, 508 (9th Cir. 2017) (complete Uzi parts kits 

‘‘could ‘readily be converted to expel a projectile by 

the action of an explosive,’ thus meeting the 

statute’s definition of firearm’’ because the ‘‘kits 

contained all of the necessary components to 

assemble a fully functioning firearm with relative 

ease’’); United States v. Stewart, 451 F.3d 1071, 

1073 n.2 (9th Cir. 2006) (upholding district court’s 

finding that .50 caliber rifle kits with incomplete 

receivers were ‘‘firearms’’ under section 

921(a)(3)(A) because they could easily be converted 

to expel a projectile). 

91See Bond v. U.S., 572 U.S. 844, 861 (2014) 

(citing dictionary definitions, and concluding that 

non-lethal irritant chemical was not a weapon). 92See, e.g., United States v. Wada, 323 F. Supp. 

2d 1079, 1081 (D. Or. 2004) (ornaments that ‘‘would 

take a great deal of time, expertise, equipment, and 

materials to attempt to reactivate’’ were no longer 

firearms). 93See, e.g., Lunde Arms Corp. v. Stanford, 107 F. 

Supp. 450, 452 (S.D. Cal. 1952), aff’d, 211 F.2d 464 

(9th Cir. 1954) (small muzzle loading toy cap gun 

that expelled non-lethal bird shot was not a 

‘‘weapon’’); Rev. Rul. 54–519, 1954–2 C.B. 438 

(inexpensive plastic toy gun was not a ‘‘weapon’’). 94See H.R. Rep. No. 90–1577, at 10 (June 21, 

1968) (‘‘[P]owder actuated industrial tools used for 

their intended purpose are not considered weapons 

and, therefore, are not included in this definition.’’); 

S. Rep. No. 90–1097, at 111 (April 29, 1968) (same). 

95Cf. United States v. Thompson/Center Arms, 

504 U.S. 505, 513, n.6 (1992) (finding that a rifle— 

a type of weapon—was ‘‘made’’ under the NFA 

when a pistol was packaged together with a 

disassembled rifle parts kit even in the absence of 

‘‘combination of parts’’ language); United States v. 

Hunter, 843 F. Supp. 235, 256 (E.D. Mich. 1994) (‘‘If 

Defendants believe that conversion kits are not in 

and of themselves ‘weapons’ under § 921(a)(3), they 

forget that that section clearly envisions 

machineguns as weapons.’’); United States v. 

Drasen, 845 F.2d 731, 736–37 (7th Cir. 1988) 

(rejecting argument that a collection of rifle parts 

cannot be a ‘‘weapon’’ even in the absence of 

combination of parts language); United States v. 

Grimm, 51 M.J. 254, 254 (C.A.A.F. 1999) 

(disassembled pistol with various components 

carried in different pants pockets was a ‘‘weapon’’). 

96See footnotes 42 and 43, supra. 

97See S. Rep. No. 89–1866, at 14, 73 (Oct. 19, 

1966) (‘‘Added to the term ‘firearm’ are weapons 

which ‘may be readily converted to’ a firearm. The 

purpose of this addition is to include specifically 

any starter gun designed for use with blank 

ammunition which will or which may be readily 

converted to expel a projectile or projectiles by the 

action of an explosive.’’). 

98See S. Rep. No. 88–1340, at 14 (Aug. 7, 1967). 

The completed weapons were reassembled, 

packaged as a kit with a holster and a box of fifty 

c. Lack of Authority To Regulate 

Weapon Parts Kits 

Comments Received 

Commenters opposed to the NPRM 

specifically argued that ATF did not 

have the authority to amend the 

regulatory definition of ‘‘firearm’’ to 

include weapon parts kits because it 

runs contrary to the GCA’s definition of 

firearm. Commenters stated that the 

definition of ‘‘firearm’’ cannot be read, 

and has not been read in the cases cited 

by ATF, to include a kit containing parts 

that could be used to make a weapon 

because a kit is not itself a weapon. 

They stated that section 921(a)(3)(A) is 

clear that a firearm is a ‘‘weapon that 

can be readily converted to expel . . . , 

not the parts that can readily be 

converted to expel a projectile.’’ 

Further, commenters argued that 

including weapon parts kits would 

impermissibly expand and alter the 

statutory meaning of both ‘‘converted’’ 

and ‘‘readily.’’ They stated that ATF 

cannot equate ‘‘converted’’ with the 

proposed added words ‘‘assembled,’’ 

‘‘completed,’’ or ‘‘restored,’’ and that, 

under a plain English reading, one 

would not ‘‘convert’’ these parts into a 

weapon. The GCA uses a starter gun as 

an example of an existing item that can 

be converted. Even assuming the 

definition includes ‘‘assembled,’’ the 

commenter stated that ‘‘[a] weapon parts 

kit that does not contain most of the 

necessary components, or that needs 

machining, cannot be assembled (or 

converted) ‘readily’ i.e., ‘without much 

difficulty’ or ‘with fairly quick 

efficiency.’ ’’ 

Department Response 

The Department disagrees with 

commenters and believes the language 

of section 921(a)(3)(A) should be read to 

include weapon parts kits and 

aggregations of weapon parts that: (1) 

Are actually designed to expel a 

projectile by the action of an explosive 

in their present form or configuration, 

but cannot expel a projectile due to 

damage, poor workmanship, or design 

flaw or feature regardless of whether 

they may readily be made to function; 

or (2) may or may not be designed to 

expel a projectile by the action of an 

explosive in their present form or 

configuration, but may readily be 

converted to do so. The Federal courts 

that have addressed this issue have 

uniformly held that disassembled 

aggregations of weapon parts 89 and 

weapon parts kits 90 that may readily be 

converted to expel a projectile are 

‘‘firearms’’ under 18 U.S.C. 921(a)(3)(A). 

A ‘‘weapon’’ is defined by common 

dictionaries as ‘‘[a]n instrument of 

offensive or defensive combat,’’ see 

Webster’s Third New International 

Dictionary 2589 (2002), but there is no 

requirement in either the dictionary 

definition or section 921(a)(3)(A) that 

the instrument have a minimum level of 

utility or lethality to be considered a 

‘‘weapon.’’ 91 While the aggregation of 

parts in a kit may not yet function as a 

weapon, these parts, simply in broken 

down form, can only be completed and 

assembled as instruments that expel live 

ammunition. Weapons completed from 

the parts in these kits typically 

incorporate or accept magazines that 

hold multiple rounds of lethal 

ammunition. They are not ornaments,92

toys,93 or industrial tools.94 Requiring 

some minimum level of utility, lethality, 

or actual functionality for aggregations 

of parts that are clearly identifiable as 

unassembled, unfinished, or incomplete 

pistols, revolvers, rifles, or shotguns, 

would be reading a requirement into the 

statutory definition of ‘‘firearm’’ that is 

not present. So long as the aggregation 

of parts is clearly identifiable as an 

instrument to expel live ammunition 

(including a starter gun), that is 

sufficient under section 921(a)(3)(A) to 

constitute a ‘‘weapon.’’ 95 Indeed, 

numerous courts have recognized that 

an item was a rifle, shotgun, pistol, or 

revolver—a weapon—even though it 

was unassembled or nonfunctional due 

to missing or broken components.96

The Department agrees with 

commenters that the term ‘‘weapon 

which . . . may readily be converted 

to’’ was inserted into the definition of 

‘‘firearm’’ in the GCA to include, as an 

example, starter guns designed for use 

with blank ammunition.97 However, the 

legislative history indicates that 

Congress included these guns because 

the convertibility of these starter pistols 

was found to be a matter of serious 

concern to law enforcement. One 

example of these conversions cited in 

the legislative history of the GCA was a 

‘‘do-it-yourself gunsmith’’ who made 

out-of-State bulk purchases of starter 

pistols. ‘‘[H]e would then, at his 

residence, disassemble them, and using 

an electric hand drill mounted in a drill 

press stand, bore out the plugged barrel 

and enlarge the cylinder chambers to 

accommodate .22-caliber cartridges.’’ 98


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24685 

.22-caliber cartridges, and sold to youth gang 

members. 

99The common meaning of the term ‘‘design’’ is 

‘‘to conceive and plan out in the mind’’ or ‘‘to plan 

or have in mind as a purpose.’’ See United States 

v. Gravel, 645 F.3d 549, 551 (2d Cir. 2011) (quoting 

Webster’s Third Int’l Dictionary (1993)). 

100Section 201 of Public Law 90–618 (Title II); 26 

U.S.C 5845(h); 27 CFR 478.11, 479.11 (definition of 

‘‘unserviceable firearm’’); H.R. Rep. No. 90–1577, at 

10 (June 21, 1968) (‘‘This provision makes it clear 

that so-called unserviceable firearms come within 

the definition.’’); S. Rep. No. 90–1097, at 111 (April 

29, 1968) (same). The GCA allows an unserviceable 

curio or relic firearm other than a machinegun to 

be imported. 18 U.S.C. 925(d)(2). Unserviceable 

NFA firearms may also be transferred as a curio or 

ornament without payment of the transfer tax. 26 

U.S.C. 5852(e). 

101As explained in the next section, the 

Department also disagrees that the terms 

‘‘assembled’’ and ‘‘completed’’ cannot be equated 

with ‘‘conversion’’ because that latter term means, 

in the context of manufacturing, altering raw 

materials to make them suitable for use. See 

footnote 104, infra. 

102See ATF Letter to Private Counsel #303304, at 

3–4 (Mar. 20, 2015) (internal quotation marks 

omitted); ATF Rul. 2015–1 (an AR-type lower 

receiver that has been indexed may be classified as 

a receiver even though additional machining or 

other manufacturing process takes place to remove 

material from the cavity that allows the fire control 

components to be installed). 

103See footnotes 43 and 44, supra; see also 18 

U.S.C. 921(a)(3)(A); 26 U.S.C. 5845(b). 

104See Merriam-Webster.com, available at https:// 

www.merriam-webster.com/dictionary/convert (last 

visited Mar. 24, 2022) (The term ‘‘convert’’ means 

‘‘to alter the physical or chemical nature or 

properties of especially in manufacturing.’’); 

Samsung Electronics Co., Ltd. v. Apple Inc., 137 S. 

Ct. 429, 435 (2016) (‘‘ ‘manufacture’ means ‘the 

conversion of raw materials by the hand, or by 

machinery, into articles suitable for the use of man’ 

and ‘the articles so made.’ ’’ (citing J. Stormonth, A 

Dictionary of the English Language at 589 (1885))); 

FastShip, LLC v. United States, 892 F.3d 1298, 1303 

n.7 (Fed. Cir. 2018) (same); Cyrix Corp. v. Intel 

Corp., 803 F. Supp. 1200, 1206 (E.D. Tex. 1992) 

(referring to the manufacturing process of 

converting raw materials into computer 

coprocessors); Swiss Manufacturers Ass’n, Inc. v. 

United States, 39 Cust. Ct. 227, 233 (1957) (‘‘What 

must be kept in mind is the distinction between 

manufacturing operations which advance the 

materials as materials and manufacturing 

operations which convert the materials into the 

complete articles.’’); Dean & Sherk Co., Inc. v. 

United States, 28 Cust. Ct. 186, 189 (1952) (‘‘It may 

require more than one manufacturing process to 

convert a textile material into a new textile material 

having a new name, character, or use.’’); United 

States v. J.A. Schneider & Co., 21 C.C.P.A. 352, 357 

(Cust. & Pat. App. 1934) (referring to the process of 

taking finished products of certain processes of 

manufacture as ‘‘material for subsequent 

manufacturing processes necessary to convert them 

into parts for furniture’’); Bedford Mills v. United 

States, 75 Ct. Cl. 412, 423 (1932) (referring to a 

‘‘manufacturer’’ as ‘‘one who converts raw materials 

into a finished product’’); Stoneco, Inc. v. Limbach, 

53 Ohio St. 3d 170, 173, 560 N.E. 2d 578, 580 (Ohio. 

1990) (‘‘manufacturing is the commercial use of 

engines, machinery, tools, and implements to 

convert material into a new form, quality, property, 

or combination and into a more valuable 

commodity for sale’’); State v. American Sugar 

Refining Co., 108 La. 603, 627, 32 So. 965, 974 (La. 

Continued 

The focus on starter pistols is not on 

starter pistols themselves as a weapon, 

but on their ability to be converted to a 

functional state. As such, the 

Department sees no legal distinction 

under the GCA between starter guns that 

may readily be converted to fire, and 

pistols, revolvers, rifles, or shotguns 

parts kits that may readily be converted 

to fire. All are incomplete ‘‘weapons’’ 

that may readily be converted to fire 

under the GCA. 

Determining when a weapon 

configured as a parts kit meets the 

statutory definition of ‘‘firearm’’ 

requires a case-by-case evaluation of 

each kit. Some weapon parts kits are 

‘‘firearms’’ because they are designed to 

expel a bullet, even if they cannot 

presently fire or readily be made to 

function because of damage, poor 

workmanship, or design flaw or 

feature.99 Such weapon parts kits are 

akin to ‘‘unserviceable firearms,’’ 

defined by the GCA as ‘‘a firearm which 

is incapable of discharging a shot by 

means of an explosive and incapable of 

being readily restored to a firing 

condition’’ (emphases added).100 Some 

weapon parts kits are ‘‘firearms’’ 

because they may readily be converted 

to expel a bullet, even if they cannot yet 

expel one or function without 

additional work. 

The Department disagrees with the 

comment that weapon parts kits must 

contain all component parts of the 

weapon to be ‘‘readily’’ converted to 

expel a projectile. But the Department 

agrees that the completeness of the kit 

is an important factor in determining 

whether a weapon parts kit may readily 

be converted to expel a projectile. This 

is why one of the factors in the 

definition of ‘‘readily’’ that courts have 

relied upon in determining whether a 

weapon may ‘‘readily be restored’’ to 

fire is whether additional parts are 

required, and how easily they may be 

obtained. An essential part missing from 

the kit that cannot efficiently, quickly, 

and easily be obtained would mean that 

the weapon cannot readily be 

completed, assembled, restored, or 

otherwise ‘‘converted’’ to a functional 

state.101

d. Lack of Authority To Regulate 

‘‘Partially Complete’’ Frames or 

Receivers 

Comments Received 

Commenters argued that ATF does 

not have authority to regulate ‘‘partially 

complete frames or receivers’’ because 

section 921(a)(3)(B) is clear that a 

completed frame or receiver is not a 

weapon, but only a part of such a 

weapon. Their theory is that if a frame 

or receiver were equivalent to a weapon, 

then section 921(a)(3)(B) would be read 

as ‘‘the weapon of any such weapon’’ 

rather than ‘‘the frame or receiver of any 

such weapon.’’ Further, commenters 

stated that ATF does not have authority 

to apply the phrase ‘‘may readily be 

converted’’ to define ‘‘partially complete 

. . . frame or receiver’’ since the ‘‘may 

readily be converted’’ language was 

included in prong (A) of section 

921(a)(3) (applying to weapons) but not 

prong (B), meaning that ‘‘readily’’ 

cannot be applied to ‘‘frame or receiver’’ 

to allow for the inclusion of partially 

complete frames or receivers in the 

regulatory scheme. 

Department Response 

The Department agrees with 

commenters who stated that frames or 

receivers are not ‘‘weapons.’’ They are 

the frames or receivers ‘‘of’’ the 

weapons described in 18 U.S.C. 

921(a)(3)(A), and they are regulated as 

‘‘firearms’’ with or without the 

component parts necessary to produce 

complete weapons. 18 U.S.C. 

921(a)(3)(B). But Congress did not 

define the term ‘‘frame or receiver’’ in 

18 U.S.C. 921(a)(3)(B), and the crucial 

inquiry is at what point an unregulated 

piece of metal, plastic, or other material 

becomes a ‘‘frame or receiver’’ that is a 

regulated item under Federal law. ATF 

has long held that a piece of metal, 

plastic, or other material becomes a 

frame or receiver when it has reached a 

‘‘critical stage of manufacture.’’ To make 

this determination, ATF’s position has 

been that the item has reached a 

‘‘critical stage of manufacture’’ when it 

is ‘‘brought to a stage of completeness 

that will allow it to accept the firearm 

components to which it is designed for 

[sic], using basic tools in a reasonable 

amount of time.’’ 102 Accordingly, this 

rule explains that the terms ‘‘frame’’ and 

‘‘receiver’’ include a partially complete 

frame or receiver ‘‘that is designed to, or 

may readily be completed, assembled, 

restored, or otherwise converted’’ to 

accept the parts it is intended to house 

or hold. 

The Department disagrees with 

commenters’ suggestion that the 

Department cannot use the concepts of 

‘‘readily’’ and ‘‘converted’’ in describing 

partially complete frames and receivers 

simply because those terms appear in 

section 921(a)(3)(A). In crafting the 

language of the regulation, ATF has 

properly considered concepts 

concerning when other firearms reach 

the point at which they are regulated 

under Federal law.103 This analysis is 

also appropriate because the very 

definition of ‘‘manufacturing’’ is the 

process of ‘‘converting’’ raw materials 

into finished goods suitable for use.104


jspears on DSK121TN23PROD with RULES2
24686 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

1902) (‘‘The process of manufacture converts the 

raw material . . . into the manufactured articles’’); 

see also Prod. Liab.: Design and Mfg. Defects § 14:7 

(2d ed.) (‘‘The basic function of the manufacturing 

organization is to convert raw materials into 

finished products.’’); cf. Broughman v. Carver, 624 

F.3d 670, 675 (4th Cir. 2010) (to ‘‘manufacture’’ a 

firearm means ‘‘to render the firearm ‘suitable for 

use’ ’’). 

105See S. Rep. No. 90–1501, at 46 (Sept. 6, 1968) 

(‘‘Of course, if the frame or receiver are themselves 

unserviceable as a frame or receiver then they 

would be treated as an unserviceable machinegun. 

Any machinegun frame or receiver which is readily 

restorable would be treated as serviceable.’’); United 

States v. Thomas, No. 17–194 (RDM), 2019 WL 

4095569, at *5 (D.D.C. Aug. 29, 2019) (In holding 

that a revolver missing its trigger, hammer, and 

cylinder pin was a ‘‘frame or receiver’’ under 

section 921(a)(3)(B), the Court stated that 

‘‘Thomas’s theory also twists the statutory 

definition beyond comprehension: Under his 

theory, Congress included the ‘frame or receiver’ of 

a weapon—which is, by definition, inoperable—in 

the statutory definition, but did so only for those 

frames or receivers that are part of an operable 

weapon. The Court rejects this mind-bending 

reading of the statute.’’). 

106The Polymer 80 assembly, for example, may 

be completed in under thirty minutes. See, e.g., 

Silverback Reviews, POLYMER 80 Lower 

completion/Parts kit install, YouTube (Aug. 19, 

2019), available at https://web.archive.org/web/ 

20200331211935/https://www.youtube.com/ 

watch?v=ThzFOIYZgIg (21-minute video of 

completion of a Polymer 80 lower parts kit with no 

slide) (last visited Apr. 1, 2022). Indeed, the 

internet is replete with ‘‘numerous videos that 

provide explicit instructions on how to construct 

ghost guns.’’ Letter for Susan Wojcicki, CEO, 

YouTube, from Senators Blumenthal, Menendez, 

Murphy, Booker, and Markey at 1 (Feb. 14, 2022), 

available at https://www.blumenthal.senate.gov/ 

imo/media/doc/0215.22youtubeghostguns.pdf (last 

visited Apr. 1, 2022); Joshua Eaton, Senators call on 

YouTube to crack down on ‘ghost gun’ videos, 

NBCNews.com (Feb. 15, 2022), available at https:// 

www.nbcnews.com/news/us-news/senatorsyoutube-ghost-gun-videos-rcna16387 (last visited 

Apr. 1, 2022); Joshua Eaton, YouTube banned ‘ghost 

gun’ videos. They’re still up., NBCNews.com (Dec. 

9, 2021), available at https://www.nbcnews.com/ 

news/us-news/youtube-ghost-gun-videos-rcna7605 

(last visited Apr. 1, 2022). 

107See footnote 20, supra; see also Convicted 

Felon Nabbed in Lakeside with Meth, Ghost Guns 

and Burglary Tools, timesofsandiego.com (Jan. 29, 

2022), available at https://timesofsandiego.com/ 

crime/2022/01/29/convicted-felon-nabbed-inlakeside-with-meth-ghost-guns-and-burglary-tools/ 

(last visited Mar. 24, 2022); Kym Kemp, Felon 

found with ‘ghost gun’ arrested, says HCSO, 

kymkemp.com (Nov. 29, 2021), available at https:// 

kymkemp.com/2021/11/29/felon-found-with-ghostgun-arrested-says-hcso/ (last visited Mar. 24, 2022); 

Det. Patrick Michaud, Georgetown Arrest of a Felon 

Leads to Recovery of Ghost Gun, 

spdblotter.seattle.gov (Nov. 8, 2021), available at 

https://spdblotter.seattle.gov/2021/11/08/ 

georgetown-arrest-of-a-felon-leads-to-recovery-ofghost-gun/ (last visited Mar. 24, 2022); Deputy 

recovers ’ghost gun’ from convicted felon during 

traffic stop, fontanaheraldnews.com (Aug. 10, 

2021), available at https://

www.fontanaheraldnews.com/news/inland_empire_

news/deputy-recovers-ghost-gun-from-convictedfelon-during-traffic-stop/article_3cfe0fd0-f4a3-11ebbd31-03979dc83307.html (last visited Mar. 24, 

2022); Lehigh Valley felon was using 3D printer to 

make ‘ghost guns’ at home, Pa. attorney general 

says, lehighvalleylive.com (Jun. 29, 2021), available 

at https://www.lehighvalleylive.com/northamptoncounty/2021/06/lehigh-valley-felon-was-using-3dprinter-to-make-ghost-guns-at-home-pa-attorneygeneral-says.html (last visited Mar. 24, 2022); Press 

Release, Department of Justice, U.S. Attorney’s 

Office, District of Conn., Bridgeport Felon 

Sentenced to More Than 5 Years in Federal Prison 

for Possessing Firearms (Jan. 7, 2021), https://

www.justice.gov/usao-ct/pr/bridgeport-felonsentenced-more-5-years-federal-prison-possessingfirearms; Christopher Gavin, Winthrop man had 

homemade ‘ghost’ guns and 3,000 rounds of 

ammunition, prosecutors say, Boston.com (Aug. 5, 

2020), available at https://www.boston.com/news/ 

crime/2020/08/05/winthrop-man-had-homemadeghost-guns-prosecutors-say (last visited Mar. 24, 

2022); ‘Ghost Gun’ used in shooting that killed two 

outside Snyder County restaurant, pennlive.com 

(Jul. 14, 2020), available at https://

www.pennlive.com/crime/2020/07/ghost-gun-usedin-shooting-that-killed-two-outside-snyder-countyrestaurant.html (last visited Mar. 24, 2022); The 

gunman in the Saugus High School shooting used 

a ‘ghost gun,’ sheriff says, CNN.com (Nov. 21, 

2019), available at https://www.cnn.com/2019/11/ 

21/us/saugus-shooting-ghost-gun/index.html (last 

visited Mar. 24, 2022); How the felon killed at 

Walmart got his handgun, DA says, 

LehighValleyLive.com (March 9, 2018), available at 

https://www.lehighvalleylive.com/news/2018/05/ 

how_the_felon_killed_at_walmar.html (last visited 

Mar. 24, 2022);‘Ghost guns’: Loophole allows felons 

to legally buy gun parts online, KIRO7.com (Feb. 22, 

2018), available at https://www.kiro7.com/news/ 

local/ghost-guns-federal-loophole-allows-felons-tolegally-buy-gun-parts-online-build-assaultweapons/703695149/ (last visited Mar. 24, 2022). 

108See New York v. Burger, 482 U.S. 691, 713 

(1987) (‘‘[T]he regulatory goals of the Gun Control 

Act . . . ensure[ ] that weapons [are] distributed 

through regular channels and in a traceable 

manner’’ thus making ‘‘possible the prevention of 

sales to undesirable customers and the detection of 

the origin of particular firearms.’ ’’ (quoting United 

States v. Biswell, 406 U.S. 311, 315–16 (1972))); City 

of Chicago v. U.S. Dep’t of Treasury, Bureau of 

Alcohol, Tobacco & Firearms, 423 F.3d 777, 781 

(7th Cir. 2005) (statutes should not be read in a way 

that ‘‘would thwart Congress’ intention’’). 

109However, the Undetectable Firearms Act of 

1988, see 18 U.S.C. 922(p), which amended the 

GCA, prohibits the manufacture and possession of 

While this analysis is intended to 

capture when an item becomes a frame 

or receiver that is regulated irrespective 

of the type of technology used, 

unformed blocks of metal, liquid 

polymers, and other raw materials only 

in a primordial state would not be 

considered by this rule to be a frame or 

receiver. However, when a frame or 

receiver is broken, disassembled into 

pieces, or is a forging, casting, or 

additive printing for a frame or receiver 

(i.e., a partially complete frame or 

receiver) that has reached a stage of 

manufacture where it can readily be 

completed, assembled, restored, or 

otherwise converted into a functional 

frame or receiver, that article is a ‘‘frame 

or receiver’’ under the GCA.105

In light of the widespread availability 

of unlicensed and unregulated partially 

complete or unassembled frames or 

receivers, which are often sold as part 

of easy-to-complete kits, it is necessary 

to deter prohibited persons from 

obtaining or producing firearms by 

clarifying that incomplete frames or 

receivers can be firearms within the 

meaning of the governing law.106

Otherwise, persons could easily 

circumvent the requirements of the GCA 

and NFA, including licensing, marking, 

recordkeeping, and background checks 

(and, if a machinegun, NFA registration) 

simply by producing almost-complete 

frames or receivers, or by making a few 

minor alterations to existing frames or 

receivers that could quickly be altered 

to produce either a functional weapon, 

or a functional frame or receiver of any 

such weapon. To be sure, many 

prohibited persons have easily obtained 

them.107 A contrary rule, under which 

prohibited persons can easily make or 

acquire virtually untraceable firearms 

directly from unlicensed parts 

manufacturers, would unreasonably 

thwart Congress’s evident purpose in 

the GCA and the NFA.108 These 

principles provide further reason not to 

read into the definition of ‘‘frame or 

receiver’’ terms like ‘‘finished,’’ 

‘‘operable,’’ ‘‘functional,’’ or a minimum 

percentage of completeness (e.g., 

‘‘80.1%’’). 

e. Lack of Authority To Regulate 

‘‘Privately Made Firearms’’ 

Comments Received 

Commenters also generally stated that 

Congress did not grant any statutory 

authority to ATF to regulate PMFs. They 

explained that the GCA’s central 

premise has been based on Congress’s 

authority to regulate interstate 

commerce and that Congress has gone to 

great lengths to clarify that only those 

involved in commercial manufacturing 

are subject to the GCA. A private party, 

making a firearm for their own use, has 

never been subject to regulation. The 

commenter cited section 101 of the 

GCA, which provides that ‘‘it is not the 

purpose of this title to place any undue 

or unnecessary Federal restrictions or 

burdens on law-abiding citizens with 

the respect to the acquisition, 

possession, or use of firearms,’’ and that 

the ‘‘title is not intended to discourage 

the private ownership or use of firearms 

by law-abiding citizens.’’ Commenters 

argue that because these PMFs are made 

solely for personal use, they do not 

come under the legal purview of the 

NFA or GCA as they lack any 

substantial connection to interstate 

commerce and therefore ATF is without 

statutory authority to make any rule 

pertaining to PMFs. 

Department Response 

The Department agrees that firearms 

privately made by non-prohibited 

persons solely for personal use generally 

do not come under the purview of the 

GCA.109 This rule does not restrict lawVerDate Sep<11>2014 19:58 Apr 25, 2022 Jkt 256001 PO 00000 Frm 00036 Fmt 4701 Sfmt 4700 E:\FR\FM\26APR2.SGM 26APR2

jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24687 

any firearm that is not as detectable as the ‘‘Security 

Exemplar’’ that contains 3.7 ounces of material type 

17–4 PH stainless steel. 

110See footnote 24, supra; 18 U.S.C. 927. 

111The Department also notes that 18 U.S.C. 

922(k), which prohibits possession of a firearm with 

the ‘‘importer’s or manufacturer’s serial number’’ 

removed, obliterated, or altered, does not 

necessarily refer to the serial number placed by a 

licensed importer or a licensed manufacturer. 

abiding citizens’ ability to make their 

own firearms from parts for self-defense 

or other lawful purposes. Under this 

rule, non-prohibited persons may 

continue to lawfully complete, 

assemble, and transfer unmarked 

firearms without a license as long as 

they are not engaged in the business of 

manufacturing, importing, dealing in, or 

transacting curio or relic firearms in a 

manner requiring a license. See 18 

U.S.C. 922(a)(1), 923(a), (b). Neither the 

GCA nor this implementing rule 

requires unlicensed individuals to mark 

(non-NFA) firearms they make for their 

personal use, or to transfer them to an 

FFL for marking. Such individuals who 

wish to produce, acquire, or transfer 

PMFs should, however, determine 

whether there are any applicable 

restrictions under State or local law.110

The Department disagrees with 

comments stating that ATF does not 

have the authority to regulate PMFs 

when those firearms are received and 

transferred by FFLs like other firearms 

subject to regulation under the GCA. 

The GCA provides that all firearms 

received and transferred by FFLs must 

be traceable through licensee records 

maintained for the period and in such 

form as prescribed by regulations. 18 

U.S.C. 923(g)(1)(A), (g)(2). There is no 

exception for PMFs. 

f. Lack of Authority To Require FFLs To 

Mark Serial Numbers on ‘‘Privately 

Made Firearms’’ 

Comments Received 

Several commenters stated that ATF 

lacks the statutory authority to require 

FFL dealers to engrave serial numbers 

on PMFs. Commenters argued that 

section 923(i) of the GCA only requires 

that ‘‘licensed importers and licensed 

manufacturers’’ mark firearms. They 

pointed out that while numerous 

provisions apply to importers, 

manufacturers, dealers, and collectors, 

not all do. For example, licensed 

collectors are not required to maintain 

records of importation as they are not 

listed in the statute. Accordingly, the 

commenters argued that Congress 

expressly imposed the duty to engrave 

serial numbers only on licensed 

importers and manufacturers but not on 

licensed dealers and that ATF is 

without any statutory basis to require 

any other FFLs, such as retailers, to 

mark firearms. Further, commenters 

argued that while the GCA requires a 

firearm have ‘‘a serial number engraved 

or cast on the receiver or the frame of 

the weapon,’’ this does not provide 

authority for ATF to require placement 

of multiple serial numbers or a single 

serial number on multiple parts. 

Department Response 

The Department disagrees that, under 

the GCA, licensees other than licensed 

manufacturers and importers cannot be 

required to mark firearms. The Attorney 

General and ATF have authority to 

promulgate regulations necessary to 

enforce the provisions of the GCA, and 

requiring licensees to mark PMFs is 

such a regulation. See 18 U.S.C. 926(a); 

H.R. Rep. No. 90–1577, at 18 (June 21, 

1968); S. Rep. No. 90–1501, at 39 (Sept. 

6, 1968). ‘‘Because § 926 authorizes the 

[Attorney General] to promulgate those 

regulations which are ‘necessary,’ it 

almost inevitably confers some measure 

of discretion to determine what 

regulations are in fact ‘necessary.’ ’’ 

Nat’l Rifle Ass’n v. Brady, 914 F.2d 475, 

479 (4th Cir. 1990). ‘‘[T]he regulatory 

goals of the Gun Control Act . . . 

ensure[ ] that weapons [are] distributed 

through regular channels and in a 

traceable manner,’’ thus making 

‘‘possible the prevention of sales to 

undesirable customers and the detection 

of the origin of particular firearms.’ ’’ 

New York v. Burger, 482 U.S. 691, 713 

(1987) (quoting United States v. Biswell, 

406 U.S. 311, 315–16 (1972)). ‘‘Severely 

limiting the application of the GCA’s 

‘manufacturing’ provisions would be 

inconsistent with these goals and would 

serve to ‘undermine the congressional 

policies’ underlying the Act.’’ 

Broughman v. Carver, 624 F.3d 670, 677 

(4th Cir. 2010). 

In enacting the GCA, which amended 

the NFA, Congress clearly understood 

that persons other than licensed 

manufacturers and importers may need 

to mark firearms they make or possess 

privately with a serial number and other 

identifying information. See, e.g., 26 

U.S.C. 5842(a)–(b) (requiring unlicensed 

makers and possessors to place serial 

numbers and other marks of 

identification on NFA firearms as may 

be prescribed by regulations).111 The 

GCA requires licensees to record firearm 

information for purposes of tracing. Yet 

licensees have no serial number or other 

identifying information marked on the 

frame or receiver of a privately made 

(non-NFA) firearm that they can record 

in cases where a licensed manufacturer 

does not produce the firearm or an 

importer does not import the firearm, 

unless they are able to mark such 

firearms when received into inventory. 

Under 18 U.S.C. 923(i), licensed 

importers and manufacturers are 

required to mark firearms, but it does 

not prohibit others from also doing so. 

The GCA’s silence on the specific 

manner in which licensees are to mark 

the firearms that they receive into 

inventory cannot be construed as a 

prohibition against any marking 

requirement through regulation. 

This rule is necessary to ensure the 

continuing fulfillment of the 

congressional intent to mark and allow 

for tracing of all firearms. If licensees 

accept PMFs into their inventories with 

no identifying markings, then the 

required records they maintain would 

be rendered meaningless because there 

would be almost no information—only 

the ‘‘type’’ of firearm—recorded in the 

A&D records, ATF Forms 4473, Theft/ 

Loss Reports, and Reports of Multiple 

Sales. The information in these records 

is essential to public safety in that they 

are used to trace firearms involved in a 

crime and to prevent straw purchasers 

from acquiring them. There would be 

little point inspecting the records of 

FFLs that do not contain serial numbers, 

which are critical to solving and 

preventing crime. 

In this regard, 18 U.S.C. 923(g)(1)(A) 

and (g)(2) specifically authorize ATF to 

prescribe regulations with respect to the 

records regarding importation, 

production, shipment, receipt, sale, or 

other disposition of firearms. By 

regulation, a firearm’s serial number and 

other identifying information are 

required to be entered on all Forms 

4473, A&D records, and ATF Forms 6/ 

6A import permit applications. See 27 

CFR 478.112(b)(1)(iv)(G), 

478.113(b)(1)(iv)(G), 478.114(a)(1)(v)(G), 

478.122(a)–(b), 478.123(a)–(b), 

478.124(c)(4), 478.125(e), 478.125a(a)(4). 

Licensees are also required to submit 

theft/loss reports and ATF Forms 

3310.11 (pursuant to 18 U.S.C. 

923(g)(6)), and multiple sales and 

demand letter transaction reports, ATF 

Forms 3310.4, 3310.12, and 5300.5 

(pursuant to 18 U.S.C. 923(g)(3)(A) and 

(g)(5)(A)), all of which require reporting 

of the serial number and other 

identifying information. As explained in 

this rule, these records and reports are 

largely meaningless without a unique 

identifying number and associated 

licensee information. Therefore, in order 

for licensees to comply with recording 

and reporting this information as 

required, it is incumbent on them to 

serialize—or cause to be serialized—all 

firearms that are taken into their 

inventories. 


jspears on DSK121TN23PROD with RULES2
24688 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

112See ATF Rul. 2009–1. While this ruling 

explains that gunsmiths who engage in the business 

of camouflaging or engraving firearms must be 

licensed as dealers, that ruling is superseded by this 

rule to the extent that those processes are performed 

on firearms ‘‘for purposes of sale or distribution,’’ 

requiring a license as a manufacturer. See 18 U.S.C. 

921(a)(10), (a)(21)(A), 923(a). To address concerns 

and reduce the burden on licensed gunsmiths 

required to be re-licensed as manufacturers, this 

final rule expressly authorizes licensed 

manufacturers to adopt the existing markings on 

firearms unless they have been sold or distributed 

to a person other than a licensee. Additionally, the 

final rule clarifies that licensed manufacturers and 

importers, who are permitted to act as licensed 

dealers without obtaining a separate dealer’s 

license, can conduct same-day adjustments or 

repairs on firearms without recording an acquisition 

provided the firearm is returned to the person from 

whom it was received. Further, this rule allows 

licensees who do not have engraving equipment to 

take a PMF to and directly supervise on-the-spot 

engraving of a serial number on the firearm by 

another licensee or even an unlicensed engraver so 

long as the dealer does not relinquish supervisory 

control over the firearm. 

At the time the GCA was enacted, 

almost all firearms were commercially 

produced by manufacturers (either 

within or outside the U.S.) because the 

milling equipment, materials needed, 

and designs were far too expensive for 

individuals to make firearms practically 

or reliably on their own. But today, 

firearms may be made at home from 

commercially produced parts kits by 

purchasing individual parts or using 

personally owned or leased equipment, 

including 3D printers. Also, cheaper 

materials, such as polymer plastics, 

along with blueprints and instructions, 

are now readily available over the 

internet. When Congress enacted the 

GCA, it likely did not consider that 

unmarked PMFs would enter the 

business or collection inventories of 

licensees, at least not in any significant 

number. ‘‘But whatever the reason, the 

scarcity of controls in the secondary 

market provides no reason to gut the 

robust measures Congress enacted at the 

point of sale.’’ Abramski v. United 

States, 573 U.S. 169, 187 (2014). 

Further, the rule necessarily allows 

licensed firearms dealers, including 

gunsmiths, to mark PMFs because 

licensed manufacturers and importers 

may refuse to provide these services as 

they are generally focused on their own 

production or importation of firearms. 

Without this change, the availability of 

professional marking by dealergunsmiths would be greatly limited and 

the efficacy of the rule would also be 

reduced if unlicensed individuals had 

fewer options to have their PMFs 

professionally marked. Moreover, 

allowing licensed firearms dealers, or 

licensed or unlicensed persons under 

the direct supervision of licensed 

firearms dealers, to properly mark 

firearms in a manner that ATF can trace 

directly to them reduces the tracing 

burden on manufacturers and importers, 

as well as law enforcement. It also 

provides dealers with the opportunity to 

earn additional income from repairing, 

customizing, or pawning firearms that 

are privately made—firearms that are 

highly likely to proliferate throughout 

the marketplace over time as firearms 

production technology develops. 

Licensed dealer-gunsmiths, in 

particular, are well-equipped to provide 

these services as they routinely engage 

in the business of engraving, painting, 

camouflaging, or otherwise customizing 

firearms for unlicensed individuals.112

Finally, the Department agrees with 

comments saying that the placement of 

multiple serial numbers on multiple 

frames or receivers of PMFs would be 

burdensome and costly for licensees, 

and would make it more difficult for 

law enforcement to trace firearms, 

including PMFs. For this reason, ATF is 

finalizing this rule to require placement 

of an individual serial number on a 

single frame or receiver of a given 

firearm. This does not mean, however, 

that it is impossible for a firearm to have 

more than one serial number marked on 

the frame or receiver. For example, a 

remanufacturer or importer who does 

not adopt an existing serial number as 

expressly allowed under this rule may 

re-mark the firearm with their own 

unique serial number. This has always 

been the case under current regulations. 

Additionally, multi-piece frames or 

receivers as defined in this rule may 

have the serial number marked on 

different sides of the same frame or 

receiver. The Department nonetheless 

believes these circumstances are rare. 

g. Violates the Administrative Procedure 

Act 

Comments Received 

Numerous commenters objected to the 

NPRM on grounds that it is nothing 

more than a politically motivated 

rulemaking, demonstrated by ATF’s use 

of a politicized nomenclature (i.e., 

‘‘ghost guns’’) and reports that 

rulemaking was directed by certain 

lobbying groups. They further argued 

that the entire rule is arbitrary and 

capricious under 5 U.S.C. 706(2)(A) of 

the Administrative Procedure Act 

(‘‘APA’’) because the agency relied on 

factors that Congress did not intend for 

it to consider. As an example, 

commenters stated that the definitions 

of ‘‘partially complete’’ and ‘‘split or 

modular frame or receiver’’ rely on 

balancing tests that have no weighted or 

comprehensible standard and can create 

unfair surprise. 

Moreover, commenters argued the 

rule violates the APA because the 

proposed definitions are arbitrary and 

capricious and because they fail to 

account for the reliance interests of 

those affected by the action and fail to 

explain the agency’s departure from 

prior policy. For example, commenters 

said that ATF’s proposal to change 

serial marking requirements and the 

definition of ‘‘gunsmith’’ fails to provide 

any data or explanation as to how traces 

are failing under the current system due 

to existing marking requirements or why 

the definition for ‘‘gunsmith’’ is 

suddenly changing after many years. 

Numerous commenters further argued 

that the rule, especially with respect to 

the proposed definition of ‘‘frame or 

receiver’’ to include partially completed 

frames or receivers, is arbitrary because 

the agency failed to address why it is 

deviating from its legal reasoning that it 

had made in recent past cases before 

Federal courts and on which the public 

relied. For example, commenters 

highlighted ATF’s arguments presented 

in City of Syracuse v. ATF, 1:20–cv– 

06885, 2021 WL 23326 (S.D.N.Y. Jan. 2, 

2021), and California v. ATF, 3:20–cv– 

06761 (N.D. Cal.). In ATF’s Motion to 

Dismiss in California, the agency wrote: 

‘‘The longstanding position of ATF is 

that, where a block of metal (or other 

material) that may someday be 

manufactured into a receiver bears no 

markings that delineate where the firecontrol cavity is to be formed and has 

not yet been even partially formed, that 

item is not yet a receiver and may not 

‘readily be converted to expel a 

projectile.’ ’’ Fed. Defs.’ Mot. Dismiss, at 

2, ECF No. 29 (Nov. 30, 2020). One 

commenter pointed out that, in that 

same Motion to Dismiss, ATF stated that 

its refusal to classify unfinished lower 

receivers as firearms is based on 

concurring expertise from DOJ. Id. at 

18–19 (citing Shawn J. Nelson, 

Unfinished Lower Receivers, 63 U.S. 

Attorney’s Bulletin No. 6 at 44–49 (Nov. 

2015)). Similarly, commenters stated 

that ATF was clear in City of Syracuse 

that ‘‘an unmachined frame or receiver 

is not ‘designed to’ expel a projectile 

because its purpose is not to expel a 

projectile. Rather its purpose is to be 

incorporated into something else that is 

designed to expel a projectile.’’ Mem. 

Supp. Fed. Defs.’ Mot. Summ. J., at 21, 

ECF No. 98 (Jan. 29, 2021). Another 

commenter cited Police Automatic 

Weapons Services, Inc. v. Benson, 837 

F. Supp. 1070 (D. Or. 1993), in which, 

before Congress ended the manufacture 

of machineguns for sale to ordinary 

persons, ATF had apparently refused to 

register incomplete machinegun 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24689 

receivers because they were not 

complete enough to be considered a 

receiver. Similarly, one manufacturer 

stated that the rule’s more expansive 

regulation governing frames or receivers 

would run counter to the legal reasoning 

ATF relied on in three prior 

classifications to the company dated 

February 2015, November 2015, and 

January 2017 regarding certain types of 

receiver blanks. 

Department Response 

The Department disagrees that this 

rulemaking violates the APA or is an 

arbitrary or capricious reaction to the 

proliferation of ‘‘ghost guns.’’ This rule 

cites ATF statistics and media reports 

demonstrating the steady increase in the 

number of PMFs recovered from crime 

scenes (including homicides) 

throughout the country, and the small 

number of crime gun traces to an 

individual purchaser that were 

successful in relation to numerous 

attempted traces of PMFs (generally by 

tracing a serial number engraved on a 

handgun slide, barrel, or other firearm 

part not currently defined as a frame or 

receiver, but recorded by licensees in 

the absence of other markings). The 

NPRM and this rule cite numerous 

criminal cases brought by the 

Department against unlicensed persons 

who were engaged in the business of 

manufacturing and selling PMFs 

without a license, and prohibited 

persons found in possession of such 

weapons. This rule cites reports and 

studies showing that the problem of 

untraceable firearms being acquired and 

used by violent criminals and terrorists 

is international in scope. This rule 

details how unmarked firearms 

undermine the GCA’s comprehensive 

regulatory scheme that requires 

licensing, marking, recordkeeping, and 

background checks for all firearms 

acquired and transferred by or through 

firearms licensees. This rule further 

explains how allowing persons to be 

licensed as dealer-gunsmiths will make 

professional marking services more 

available to unlicensed individuals, and 

make it possible for other licensees to 

receive and transfer PMFs should they 

choose to accept them into inventory in 

the course of their licensed activities. 

The Department carefully considered all 

commenters’ concerns in finalizing this 

rule in accordance with the APA. 

The Department does not agree with 

commenters who said that the number 

of PMFs involved in crime should be 

compared with the number of all 

firearms involved in crime. At the 

outset, there is no threshold for 

establishing when law enforcement 

agencies may take steps to reduce 

violent crime. The subset of traces for 

PMFs is obviously fewer than those of 

commercially manufactured crime guns, 

which bear serial numbers and other 

identifying markings and make up a 

much greater volume of marked 

weapons in circulation, and firearms 

with serial numbers are much more 

likely to be traced successfully by law 

enforcement than PMFs without serial 

numbers. Regardless, with better and 

cheaper technologies, unmarked 

firearms are becoming more easily and 

repeatedly made by individuals using 

personally owned or leased equipment, 

including 3D printers. It is clear from 

this data that PMFs are increasingly 

being used in crime throughout the 

United States and internationally with 

no reason to believe the trend will not 

continue. Statistics concerning crime 

gun tracing of commercially 

manufactured firearms do not lessen the 

necessity of this rule to improve public 

safety in the context of unmarked PMFs. 

The Department disagrees with 

commenters who said that ATF is 

changing its position that a solid block 

of metal (or other material) that may 

someday be manufactured into a 

receiver that bears no markings that 

delineate where the fire-control cavity is 

to be formed, and has not yet been even 

partially formed, is not a ‘‘receiver.’’ 

Machining, indexing, or lack thereof, to 

the fire-control cavity remain an 

important factor in the readily 

completed, assembled, restored or 

otherwise converted analysis. To 

buttress this point, the final rule 

expressly excludes from the definitions 

of ‘‘frame’’ and ‘‘receiver,’’ ‘‘a forging, 

casting, printing, extrusion, 

unmachined body, or similar article that 

has not yet reached a stage of 

manufacture where it is clearly 

identifiable as an unfinished component 

part of a weapon (e.g., unformed block 

of metal, liquid polymer, or other raw 

material).’’ In other words, an item in a 

primordial state, such as a solid block 

of metal, liquid polymer, raw material, 

or other item that is not clearly 

identifiable as a component part of a 

weapon, is not a ‘‘frame’’ or ‘‘receiver’’ 

under this rule. This rule as proposed 

and finalized clarifies the distinction 

between a primordial object and a 

partially complete frame or receiver 

billet or blank that may be considered 

a ‘‘frame’’ or ‘‘receiver’’ under certain 

circumstances. 

However, prior to this rule, ATF did 

not examine templates, jigs, molds, 

instructions, equipment, or marketing 

materials in determining whether 

partially complete frames or receivers 

were ‘‘firearms’’ under the GCA. For this 

reason, ATF issued some classifications 

concluding that certain partially 

complete frames or receivers were not 

‘‘frames or receivers’’ as now defined in 

this rule. This change to allow 

consideration of templates, jigs, 

instructions, etc. in classification 

determinations does not run afoul of the 

APA. See F.C.C. v. Fox, 556 U.S. 502, 

517 (2009) (Federal Communications 

Commission did not act arbitrarily when 

it changed its policy regarding fleeting 

expletives). The Supreme Court ‘‘fully 

recognize[s] that regulatory agencies do 

not establish rules of conduct to last 

forever and that an agency must be 

given ample latitude to adapt [its] rules 

and policies to the demands of changing 

circumstances.’’ Motor Vehicle 

Manufacturer’s Ass’n v. State Farm Mut. 

Auto. Ins. Co., 463 U.S. 29, 41 (1983) 

(citation and internal quotation marks 

omitted). The aggregation of a template 

or jig with a partially complete frame or 

receiver, such as those included in 

firearm parts kits, can serve the same 

purpose as indexing, making an item 

that is clearly identifiable as a partially 

complete frame or receiver into a 

functional one efficiently, quickly, and 

easily (i.e., ‘‘readily’’). Because indexing 

allows partially complete frames or 

receivers to be completed efficiently, 

quickly, and easily, such articles will 

now be considered frames or receivers 

under this rule. As stated in the NPRM 

and this final rule, changing 

circumstances—i.e., more advanced and 

accessible technology, the subsequent 

proliferation of ‘‘80% receivers,’’ and 

the resulting threat to public safety from 

unserialized firearms—necessitate this 

change. 

With regard to the comment on 

gunsmiths, the rule is necessary to 

explain who is required to be licensed 

as a gunsmith, as distinguished from a 

manufacturer. In addition to comments 

concerned with the application of the 

proposed definition, ATF has received 

numerous inquiries over the years 

asking whether persons are required to 

be licensed as dealer-gunsmiths (Type 

01) or manufacturers (Type 07). See, 

e.g., ATF Ruls. 2009–1, 2009–2, 2010– 

10, and 2015–1. The current definition 

of ‘‘engaged in the business’’ in 18 

U.S.C. 921(a)(21)(D) and ‘‘gunsmith’’ in 

27 CFR 478.11 describe a gunsmith as 

a ‘‘person who devotes time, attention, 

and labor to engaging in such activity as 

a regular course of trade or business 

with the principal objective of 

livelihood and profit’’ without 

explaining the range of commercial 

activities gunsmiths perform, or when 

those activities can be performed on 

firearms for sale or distribution without 

a manufacturer’s license. This rule, 


jspears on DSK121TN23PROD with RULES2
24690 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

113The out-of-business firearms transaction 

records are indexed by abbreviated FFL number so 

that they may be accessed when needed to complete 

a firearm trace request involving a licensee that is 

no longer in business. Out-of-business firearms 

transaction records are not searchable by an 

individual’s name or other personal identifiers. In 

2006, ATF transitioned from using microfilm 

images of records to scanning records into a digital 

storage system with images that are not searchable 

through character recognition, consistent with 

ATF’s design and use of its prior Microfilm 

Retrieval System. A 2016 GAO Audit (GAO–16– 

552) concluded that ATF’s digital system complies 

with the restrictions prohibiting consolidation or 

centralization of FFL records. See also Statutory 

Federal Gun Registry Prohibitions and ATF Record 

Retention Requirements, Congressional Research 

Service (March 4, 2022), https://

crsreports.congress.gov/product/pdf/IF/IF12057 

(last visited Apr. 3, 2022). 

114See 124 Cong. Rec. 16637 (June 7, 1978) 

(statement of Rep. Drinan) (‘‘The most frequent 

criticism of the March 21 regulations is their alleged 

establishment of a ‘national gun registration’ 

system. Is it possible to establish such a system 

under a set of regulations which prohibit the 

submission, collection, or maintenance on file of 

the identifies of owners and purchasers of firearms? 

Clearly, the answer is no. These regulations are not 

directed at gun purchasers; they are designed 

instead to aid law enforcement officers by requiring 

that firearms manufacturers and dealers keep track 

of firearms transactions. Put more simply, the 

regulations will trace guns, not gun owners. 

Individual purchasers of firearms will not have to 

register their weapons, and the Bureau will not 

establish a centralized registry of firearms 

owners.’’). 

therefore, necessarily clarifies the 

meaning of that term. 

h. Violates the Prohibitions Against 

Creation of a Gun Registry 

Comments Received 

Numerous commenters objected to the 

proposed serial marking requirements, 

claiming it is a ploy by the Government 

to subject law-abiding gun owners who 

enjoy and have the right to build their 

own firearms to a rigorous registration 

requirement. They claimed that the 

requirement that PMFs be serialized 

only leads to an illegal gun registry, 

which ATF is forbidden from creating 

under Federal law. Commenters 

similarly opined that the extended 

recordkeeping requirement is a clear 

sign that ATF intends to have a registry 

of all firearms owners going far beyond 

those who are legally required to 

register firearms under the NFA. 

Department Response 

The Department disagrees that this 

rule creates a registry of PMFs, for 

several reasons. First, neither the GCA 

nor this implementing rule requires 

unlicensed individuals to mark (nonNFA) firearms they make for their 

personal use, or when they occasionally 

acquire them for, or sell or transfer them 

from, a personal collection to 

unlicensed in-State residents consistent 

with Federal, State, and local law. There 

are also no recordkeeping requirements 

imposed by the GCA or this rule upon 

unlicensed persons who make their own 

firearms, but only upon licensees who 

choose to take PMFs into inventory. 

And, under this final rule, when FFLs 

do choose to accept PMFs into 

inventory, and no manufacturer name 

has been identified on a PMF (if 

privately made in the United States), the 

words ‘‘privately made firearm’’ (or the 

abbreviation ‘‘PMF’’) are required to be 

recorded as the name of the 

manufacturer, not the name of the actual 

private maker. 

Second, records of production, 

acquisition, and disposition of all 

firearms are required by the GCA, 18 

U.S.C. 923(g)(1)(A) and (g)(2), to be 

completed and maintained by FFLs at 

their licensed business premises for 

such period, and in such form, as the 

Attorney General may prescribe by 

regulations. In this rule, ATF is 

exercising that authority to change the 

manner and duration in which those 

records are maintained. At present, 

licensees are required to maintain their 

acquisition and disposition records for 

at least 20 years. This rule merely 

extends the 20-year retention period so 

that those records are not destroyed, and 

thus can be used for tracing purposes. 

Although ATF has the authority to 

inspect an FFL’s records under certain 

conditions, see 18 U.S.C. 923(g)(1)(B)– 

(C), the records belong to and are 

maintained by the FFLs, not the 

government. Only after an FFL 

discontinues business does the GCA, 18 

U.S.C. 923(g)(4), require FFLs to provide 

their records to ATF so that tracing of 

crime guns can continue.113 In fact, the 

provision cited by some commenters, 18 

U.S.C. 926(a), expressly provides that 

‘‘[n]othing in this section expands or 

restricts the Secretary’s authority to 

inquire into the disposition of any 

firearm in the course of a criminal 

investigation.’’ Moreover, Federal law 

has long prohibited ATF from 

consolidating or centralizing licensee 

records. Since 1979, congressional 

appropriations have prohibited ATF 

from using any funds or salaries for the 

consolidation or centralization of 

records of acquisition and disposition of 

firearms maintained by FFLs. See 

Treasury, Postal Service, and General 

Government Appropriations Act, 1980, 

Public Law 96–74, 93 Stat. 559, 560 

(1979). This annual restriction became 

permanent in 2011. See Public Law 

112–55, 125 Stat. 632 (2011). Thus, ATF 

is already restricted by law from 

creating any such registry, and this rule 

does not create one.114

i. Violates 18 U.S.C. 242 and 1918 

Comments Received 

Out of concern regarding their rights 

under the Second Amendment to the 

U.S. Constitution, several commenters 

claimed that by working on this rule, 

ATF officials are violating 18 U.S.C. 

242, which makes it a crime for a person 

acting under color of any law to 

willfully deprive a person of a right or 

privilege protected by the Constitution 

or laws of the United States. 

Commenters also claim that ATF 

officials and employees are likewise 

violating their oath of office to support 

and defend the U.S. Constitution 

(particularly the Second Amendment), 

which the commenters state is 

punishable under 18 U.S.C. 1918. 

Department Response 

The Department disagrees that any 

official involved in promulgating or 

implementing this rule violates 18 

U.S.C. 242 or 1918, or any other Federal 

law. As stated previously, this rule does 

not impact the Second Amendment 

rights of law-abiding citizens to keep 

and bear firearms for lawful personal 

use. The regulations proposed and 

finalized herein do not raise Second 

Amendment concerns because they are 

‘‘presumptively lawful regulatory 

measures’’ that ‘‘impos[e] conditions 

and qualifications on the commercial 

sale of arms.’’ Heller, 554 U.S. at 626– 

27 & n.26. 

3. Concerns With Proposed Definitions 

a. General Concerns With Proposed 

Definitions 

Comments Received 

Numerous commenters stated that no 

changes to the regulations are needed 

because the current definitions are 

adequate. They also believe that ATF’s 

private letter rulings are adequate 

communications to provide information 

to the industry and firearms owners. 

Commenters opposed to the proposed 

definitions and new terms in the NPRM 

stated that the new definitions, which 

they assert are vague, use terms and 

phrases that are even more unclear. For 

instance, commenters argued that 

although ‘‘partially complete receiver’’ 

is defined, the definition has even more 

vague, problematic terms such as 

‘‘clearly identifiable,’’ ‘‘unfinished 

component part of a weapon,’’ ‘‘critical 

stage of manufacture,’’ ‘‘sufficiently 

complete to function,’’ and ‘‘primordial 

state.’’ Similar to the due process and 

APA concerns discussed earlier, one 

major objection of commenters to the 

proposed definitions was that the 

definitions are too broad to be workable. 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24691 

A majority of these comments focused 

on the supplemental definitions of 

‘‘split or modular frame or receiver’’ and 

‘‘partially complete, disassembled, or 

inoperable frame or receiver.’’ 

Several commenters stated that the 

very problem ATF is trying to solve is 

made worse by the proposed 

regulations, as no reasonable person 

would be able to determine which 

component or components of a given 

firearm constitute a frame or receiver. 

As summed up by some commenters: 

‘‘The proposed definition creates a 

reality where a reasonable person would 

be forced to assume that every 

component of the firearm which meets 

the proposed definition of firearm frame 

or receiver is such, unless they are 

aware of a determination to the contrary 

by ATF. Therefore, consumers must 

constantly be in doubt as to whether a 

firearm in their possession has been 

properly marked in accordance with the 

law, or if they are in possession of an 

illegal item.’’ Moreover, as discussed in 

Section IV.B.13.b of this preamble, 

numerous commenters opined that the 

proposed definition of ‘‘frame or 

receiver’’ and its supplemental 

definitions, which would trigger new 

marking or recordkeeping requirements, 

would be cost prohibitive to the 

industry and to firearms owners. 

Department Response 

The Department disagrees with 

commenters who stated that the current 

definitions are adequate. The NPRM and 

this final rule explain in detail how the 

current definitions of ‘‘firearm frame or 

receiver’’ and ‘‘frame or receiver’’ in 27 

CFR 478.11 and 479.11 do not 

adequately describe the major 

component of split or modular weapons 

or muffler or silencer devices required 

to be identified and recorded by 

licensees as a ‘‘firearm.’’ The current 

definition describes a housing for three 

fire control components: Hammer, bolt 

or breechblock, and firing mechanism. 

But the vast majority of firearms in 

common use today do not have a single 

housing for all of those components, 

and numerous firearms today are not 

hammer-fired. They often have split 

frame or receiver designs, and many are 

striker-fired. As stated previously, three 

courts have already applied ATF’s 

definition of ‘‘frame or receiver’’ in a 

way that would leave most firearms 

currently in circulation in the United 

States without an identifiable frame or 

receiver. See United States v. Rowold, 

429 F. Supp. 3d 469, 475–76 (N.D. Ohio 

2019) (‘‘The language of the regulatory 

definition in § 478.11 lends itself to only 

one interpretation: Namely, that under 

the GCA, the receiver of a firearm must 

be a single unit that holds three, not two 

components: (1) The hammer, (2) the 

bolt or breechblock, and (3) the firing 

mechanism.’’); United States v. Roh, 

SACR 14–167–JVS, Minute Order p. 6 

(C.D. Cal. July 27, 2020); United States 

v. Jimenez, 191 F. Supp. 3d 1038, 1041 

(N.D. Cal. 2016). 

The proposed new terms and 

definitions are also needed to explain 

when weapon parts kits, frame or 

receiver parts kits, and multi-piece 

frames or receivers are ‘‘firearms’’ and 

thus subject to regulation, and how 

licensees can accept unmarked PMFs 

into their inventories. The rule points 

out that silencer manufacturers are 

currently uncertain when and how each 

small silencer part must be marked 

given that each part is defined as a 

‘‘silencer’’ under the law. Clarifying 

these issues in individual private letter 

rulings is not adequate to provide 

sufficient notice and guidance to the 

licensed community and public at large 

as to how firearms are defined and 

regulated. In addition, letter rulings are 

only applicable for the precise sample 

submitted to ATF, and those 

classifications may then be misapplied 

(as some have done) to other items that 

may appear similar, but have legally 

important differences. For these reasons, 

the Department has addressed these 

issues through this rulemaking to 

promulgate new definitions that apply 

to all existing firearm designs as well as 

to accommodate future changes in 

firearms technology and terminology. 

Nonetheless, the Department agrees 

with commenters that the supplement to 

the proposed definition of ‘‘frame or 

receiver’’ entitled ‘‘split or modular 

frame or receiver’’ could have been 

costly to licensees to implement, and 

that the supplement ‘‘partially 

complete, disassembled, or inoperable 

frame or receiver’’ should be revised to 

provide more clarity on how it applies 

to the definition of ‘‘frame or receiver.’’ 

In response to comments, in the final 

rule the Department has removed the 

supplement entitled ‘‘split or modular 

frame or receiver,’’ made additions to 

explain how multi-piece frames or 

receivers must be identified, and made 

clarifying changes to the supplement 

entitled ‘‘partially complete, 

disassembled, or inoperable frame or 

receiver.’’ 

Finally, although the Department 

disagrees that certain terms in this rule 

were vague, additional clarity has been 

provided to explain the meaning of 

those terms. Examples of articles that 

are ‘‘clearly identifiable as an 

unfinished component part of a 

weapon’’ are unformed blocks of metal, 

liquid polymers, and other raw 

materials. The dictionary definition of 

the term ‘‘primordial’’ was adopted and 

explained in footnote 49 of this 

preamble. The term ‘‘sufficiently 

complete to function as a frame or 

receiver’’ is no longer used in the 

regulatory text. That term was replaced 

with ‘‘to function as a frame or 

receiver,’’ which is described as ‘‘to 

house or provide a structure for the 

primary energized component of a 

handgun, breech blocking or sealing 

component of a projectile weapon other 

than a handgun, or internal sound 

reduction component of a firearm 

muffler or firearm silencer, as the case 

may be.’’ 

b. Definition of ‘‘Firearm’’ and Weapon 

Parts Kits 

Comments Received 

In addition to stating that ATF does 

not have authority to include weapon 

parts kits in the definition of ‘‘firearm,’’ 

several commenters also stated the 

definition was flawed and would serve 

no purpose. For instance, commenters 

said it is futile to regulate a weapon 

parts kit because a kit could be sold 

without a firing pin and thus would not 

be in a state where it is readily 

completable, enabling kit manufacturers 

to circumvent the definition by selling 

the kit separately from a cheap and 

readily available pin. Other commenters 

stated that if ATF’s definitions mean 

that a ‘‘weapon parts kit’’ containing all 

unregulated parts, including a so-called 

‘‘80% receiver,’’ is a ‘‘firearm,’’ this 

would raise the question of whether a 

kit with a forging in a primordial state 

is still a firearm because the pieces 

taken together could expel a projectile 

by an action of an explosive even if it 

is not readily convertible for that 

purpose. They stated that under ATF’s 

interpretation it appears to be irrelevant 

whether the part that could become the 

frame or receiver ‘‘may readily be 

converted’’ as long as it is ‘‘designed to 

expel a projectile by action of an 

explosive.’’ Separately, since the 

preamble described ‘‘weapons parts 

kits’’ as having ‘‘most or all of the 

components,’’ commenters questioned 

whether a kit that does not contain all 

of the necessary components to expel a 

projectile by the action of an explosive 

is still ‘‘designed’’ or ‘‘readily 

convertible’’ to do so. Commenters thus 

sought more clarity on what 

components must be present in a kit to 

constitute a firearm. 

Department Response 

The Department disagrees with 

commenters that including weapon 

parts kits in the definition of ‘‘firearm’’ 


jspears on DSK121TN23PROD with RULES2
24692 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

115See, e.g., United States v. Rivera, 415 F.3d 

284, 285–87 (2d Cir. 2005) (pistol with a broken 

firing pin and flattened firing-pin channel); United 

States. v. Brown, 117 F.3d 353, 356 (7th Cir. 1997) 

(gun with no firing pin); United States v. Hunter, 

101 F.3d 82, 85 (9th Cir. 1996) (pistol with broken 

firing pin); United States v. Yannott, 42 F.3d 999, 

1005 (6th Cir. 1994) (shotgun with broken firing 

pin); United States v. York, 830 F.2d 885, 891 (8th 

Cir. 1987) (revolver with no firing pin and cylinder 

did not line up with barrel); United States v. 

Randolph, No. 02 CR. 850–01 (RWS), 2003 WL 

1461610, at *2 (S.D.N.Y. Mar. 20, 2003) (gun 

consisting of ‘‘disassembled parts with no 

ammunition, no magazine, and a broken firing 

pin’’). 

serves no purpose. The GCA is clear that 

when a weapon will, is designed to, or 

may readily be converted to expel a 

projectile by the action of an explosive, 

the weapon is a ‘‘firearm’’ under 18 

U.S.C. 921(a)(3)(A). As explained above 

and in the NPRM, relevant case law 

makes clear that weapon parts kits that 

are designed to or may readily be 

assembled, completed, converted, or 

restored to expel a projectile by the 

action of an explosive qualify as a 

‘‘firearm’’ under 18 U.S.C. 921(a)(3)(A). 

See Section III.A, supra; 86 FR 27726 & 

nn.39–40. The rule thus amends the 

existing definition to explicitly note this 

application of the term ‘‘firearm’’ to 

include such weapon parts kits. The 

rule also relies on existing case law to 

provide a definition of the term 

‘‘readily’’ and to detail the factors 

relevant to making that determination 

when classifying firearms. See Section 

III.C, supra; Section IV.B.3.j, infra. As 

earlier explained, in recent years, 

manufacturers and retailers have been 

selling to individuals weapon parts kits 

with incomplete frames or receivers, 

commonly called ‘‘80% receivers,’’ 

without conducting background checks 

or maintaining records. Some of these 

parts kits contain all of the necessary 

components (finished or unfinished), 

along with jigs, templates, or other tools 

that allow an individual to complete a 

functional weapon with minimal effort, 

expertise, or equipment within a short 

period of time. 

The Department disagrees with 

commenters who said that regulating 

weapon parts kits that were missing 

certain parts, such as a firing pin, would 

be futile. A weapon missing a firing pin 

is still a ‘‘firearm’’ under section 

921(a)(3)(A) because it is designed to 

expel a projectile.115 The fact that the 

same exact pistol without a firing pin 

has been disassembled into a parts kit 

does not alter the weapon’s design. 

Moreover, one of the considerations in 

determining whether a weapon, 

including a weapon parts kit, may 

‘‘readily’’ be converted to expel a 

projectile is whether additional parts are 

required, and how efficiently, quickly, 

and easily they can be obtained and 

assembled. 

The Department agrees that certain 

essential parts could be removed from 

the kit, potentially making it difficult to 

determine whether such a kit or 

aggregation of parts may readily be 

converted to fire. However, it would be 

impossible for the Department to set 

forth in the regulations a precise 

minimum percentage of completion, 

maximum time period, maximum level 

of expertise, or type or number of parts 

necessary to convert each and every 

make, model, and configuration of 

weapon parts kits now in existence, or 

that may be produced in the future. The 

Department believes that it is 

constitutionally, legally, and practically 

sufficient, and consistent with relevant 

case law, to explain in this rule that the 

conversion must be fairly or reasonably 

efficient, quick, and easy (though not 

necessarily the most efficient, speediest, 

or easiest process) after examining the 

enumerated factors. Additionally, if 

persons remain uncertain as to whether 

a particular weapon parts kit is a 

‘‘firearm,’’ they may submit a voluntary 

request to ATF for a classification in 

accordance with this rule. 

While these determinations must 

necessarily be made on a case-by-case 

basis, the Department believes that the 

term ‘‘readily’’ and the factors in this 

rule provide sufficient notice that 

certain weapon and frame or receiver 

parts kits are regulated under the GCA. 

It is not the purpose of the rule to 

provide guidance so that persons may 

structure transactions to avoid the 

requirements of the law. Persons who 

engage in the business of importing, 

manufacturing, or dealing in weapon 

and frame or receiver parts kits must be 

licensed, mark the frames or receivers 

within such kits with serial numbers 

and other marks of identification, 

conduct background checks, and 

maintain transaction records for them so 

that they can traced by law enforcement 

if involved in crime. 

c. Definition of ‘‘Frame or Receiver’’ 

Comments Received 

Despite the grandfather provision 

ATF provided in the NPRM for existing 

frames or receivers, commenters said 

there is still confusion because one 

cannot examine the definition of ‘‘frame 

or receiver’’ to determine with any 

certainty whether a specific part of a 

firearm that was previously classified as 

a single frame or receiver is redefined as 

a split or modular frame or receiver and 

whether the entire scope of the 

definition is dependent upon the 

Director. Other commenters asserted 

that the definition of ‘‘frame or receiver’’ 

is vague because ‘‘almost any housing or 

structure that is at all visible from the 

exterior [is] susceptible to a 

classification as a frame or receiver’’ or 

would make ‘‘every single part of a 

firearm a ‘fire control component’ ’’ such 

that firearms like the AR–15 may now 

include as many as ten frames or 

receivers. 

Another commenter stated that the 

open-ended nature of fire control 

components makes it difficult, if not 

impossible, to determine what 

constitutes the frame or receiver. The 

commenter explained that some 

magazine catches could be a frame or 

receiver because those components are 

visible from the exterior of a completed 

firearm and provide a structure to hold 

or integrate a component necessary for 

the firearm to initiate or continue the 

firing sequence (e.g., a magazine for use 

in a semiautomatic pistol equipped with 

a magazine disconnect). The 

commenters stated that ATF’s 

illustrations purport to indicate that 

only one part is the frame or receiver 

when in fact the depictions show 

firearms with more than one component 

that meet the definition using only the 

listed fire control components. For 

example, the commenters stated: ‘‘The 

hinged revolver example indicates that 

the ‘frame’ is the rear half of the firearm, 

even though the front half of the firearm 

obviously provides a ‘housing or 

structure’ to ‘hold or integrate’ the 

cylinder when the firearm is 

assembled.’’ Commenters also pointed 

out that ATF did not explain what it 

means by ‘‘other reliable evidence’’ 

where it stated that: ‘‘Any such part 

identified with a serial number shall be 

presumed, absent an official 

determination by the Director or other 

reliable evidence to the contrary, to be 

a frame or receiver.’’ Given that firearms 

classifications are not released to the 

public, the commenters questioned how 

anyone is to know whether a given 

firearm has or has not received an 

official determination. 

Department Response 

The Department believes that the 

grandfather provision in the proposed 

rule would have eliminated most of the 

concerns raised by commenters 

concerning the proposed definition of 

‘‘frame or receiver’’ and agrees that it 

relied heavily on ATF classifications of 

specific components as a ‘‘frame or 

receiver.’’ Nonetheless, as stated 

previously, the Department agrees with 

commenters that the definition of 

‘‘firearm’’ in 18 U.S.C. 921(a)(3)(B) is 

best read to mean a single part of a 

weapon or device as being ‘‘the’’ frame 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24693 

116See footnote 7, supra. 

117 Id. 

118Prasanta Kumar Das, Lalit Pratim Das, & Dev 

Pratim Das, Science and Engineering of Small 

Arms, Ch. 5.4 (2022). 

119SAAMI defines the term ‘‘receiver’’ as ‘‘[t]he 

basic unit of a firearm which houses the firing and 

breech mechanism and to which the barrel and 

stock are assembled. In revolvers, pistols, and 

break-open guns, it is called the Frame.’’ See 

SAAMI, Glossary of Industry Terms, available at 

https://saami.org/saami-glossary/?letter=R (last 

visited Mar. 25, 2022). 

or receiver. Accordingly, the final rule 

adopts certain subsets of the proposed 

definition firearm ‘‘frame or receiver’’ 

while providing new distinct definitions 

for ‘‘frame’’ and ‘‘receiver.’’ Whereas the 

proposed rule would have considered 

any housing or structure for any fire 

control component a frame or receiver, 

the final rule focuses these definitions 

by describing a specific housing or 

structure for one specific type of fire 

control component. This will help 

licensees and the public determine on 

their own which portion of a firearm is 

the ‘‘frame or receiver’’ without an ATF 

classification. 

In the final rule, the Department has 

established new definitions for the term 

‘‘frame’’ to apply to handguns; 

‘‘receiver’’ to apply to rifles, shotguns, 

and projectile weapons other than 

handguns; and ‘‘frame’’ or ‘‘receiver’’ to 

apply to firearm mufflers and silencers. 

More specifically, with respect to 

handguns, the Department is adopting 

in this final rule a definition of ‘‘frame’’ 

that incorporates language similar to 

that proposed by commenter Sig Sauer, 

Inc., described below. The term ‘‘frame’’ 

will be defined as: ‘‘the part of a 

handgun, or variants thereof, that 

provides housing or a structure for the 

primary energized component designed 

to hold back the hammer, striker, bolt, 

or similar component prior to initiation 

of the firing sequence (i.e., sear or 

equivalent), even if pins or other 

attachments are required to connect 

such component to the housing or 

structure.’’ This definition is consistent 

with the common understanding of the 

term ‘‘frame’’ as the ‘‘basic unit of a 

handgun’’ that holds the ‘‘operating 

parts’’ of the weapon.116 These 

operating parts necessarily include the 

sear or equivalent component that is 

energized prior to initiation of the firing 

sequence. 

However, the Department does not 

adopt the same definition with respect 

to rifles, shotguns, and projectile 

weapons other than handguns which are 

commonly understood to incorporate a 

‘‘receiver.’’ This term is generally 

understood to be the part ‘‘in which the 

action of a firearm is fitted and to which 

the breech end of the barrel is 

attached.’’ 117 Because the ‘‘action’’ of a 

firearm is commonly understood to 

mean ‘‘the physical mechanism that 

manipulates cartridges and/or seals the 

breech,’’ 118 the term ‘‘receiver’’ is 

defined in the final rule as: ‘‘the part of 

a rifle, shotgun, or projectile weapon 

other than a handgun, or variants 

thereof, that provides housing or a 

structure for the primary component 

designed to block or seal the breech 

prior to initiation of the firing sequence 

(i.e., bolt, breechblock, or equivalent), 

even if pins or other attachments are 

required to connect such component to 

the housing or structure.’’ 

For purposes of these definitions, the 

terms ‘‘variant’’ and ‘‘variants thereof’’ 

are defined as: ‘‘a weapon utilizing a 

similar frame or receiver design 

irrespective of new or different model 

designations or configurations, 

characteristics, features, components, 

accessories, or attachments. For 

example, an AK-type firearm with a 

short stock and a pistol grip is a pistol 

variant of an AK-type rifle, an AR-type 

firearm with a short stock and a pistol 

grip is a pistol variant of an AR-type 

rifle, and a revolving cylinder shotgun 

is a shotgun variant of a revolver.’’ The 

definition of frame or receiver with 

respect to a firearm muffler or silencer 

is described in Section IV.B.3.e of this 

preamble. The final rule does not adopt 

the proposed supplement entitled ‘‘Split 

or Modular Frame or Receiver.’’ 

Additionally, in response to 

comments, the Department has added a 

new ‘‘grandfather’’ supplement 

expressly defining the term ‘‘frame or 

receiver’’ to include prior ATF 

classifications of a specific component 

as the frame or receiver, and clarified 

how multi-piece frames or receivers 

with modular subparts are defined and 

must be marked. These amendments 

should greatly diminish commenters’ 

concerns regarding any lack of 

specificity or confusion regarding the 

particular models listed in the proposed 

definitions. The final rule includes a 

wide variety of examples and pictures to 

illustrate the frame or receiver of 

popular models and variants thereof, as 

well as examples of particular models 

previously classified by ATF that are 

grandfathered, such as the lower 

receiver of AR–15 variant firearms 

which houses the trigger mechanism 

and hammer, rather than the breech 

blocking or sealing component (i.e., the 

bolt). 

d. Alternative Definitions of ‘‘Frame or 

Receiver’’ 

Comments Received 

Commenters opposed to the proposed 

rule have either urged ATF to withdraw 

the rulemaking or come up with a more 

concise, less complex definition. While 

some commenters agreed that ATF’s 

current definition of ‘‘frame or receiver’’ 

is outdated, ‘‘antiquated,’’ or 

‘‘confusing,’’ several commenters from 

the industry said a new definition 

should be tailored to focus on new 

designs and should be done with 

meaningful input from stakeholders. 

A few commenters stated that there 

were numerous other ways for ATF to 

amend its definition to adapt to 

technological advances while also being 

consistent with the wider public’s 

longstanding interpretation of the term 

to mean a single component of a given 

firearm. Commenter Sig Sauer, Inc., for 

example, suggested the following 

possible alternative definitions: (1) 

‘‘Firearm frame or receiver’’ means ‘‘the 

component of the firearm which 

provides a housing for the component 

responsible for constraining the 

energized component of the firearm (i.e., 

the sear or equivalent thereof)’’; (2) 

‘‘Firearm frame or receiver’’ means ‘‘the 

component of the firearm which 

provides a housing for the component 

which the operator interacts with to 

initiate the firing sequence of the 

firearm (i.e., the triggering mechanism, 

or the equivalent thereof)’’; or (3) 

‘‘Firearm frame or receiver’’ means ‘‘the 

component of the firearm which 

incorporates or provides a housing for 

the component which interacts with the 

barrel to form the chamber of the 

firearm.’’ 

One commenter stated that ATF’s goal 

to update the definition of ‘‘frame or 

receiver’’ to accommodate split-framed 

firearms would be met simply by rewriting the existing definition to read: 

‘‘the part of a firearm that provides 

housing for the hammer, bolt or 

breechblock, firing mechanism, or at its 

forward portion receives the barrel.’’ 

Another commenter similarly suggested 

that ATF use ‘‘or’’ rather than ‘‘and’’ as 

the conjoiner in the current definition of 

‘‘firearm frame or receiver,’’ such that 

the list of the components housed by the 

frame or receiver would read ‘‘the 

hammer, bolt or breechblock, or firing 

mechanism.’’ Another commenter 

suggested that ATF adopt the definition 

of ‘‘receiver’’ that is in the Sporting 

Arms and Ammunition Manufacturers’ 

Institute’s (‘‘SAAMI’s’’) Glossary of 

Industry Terms available on that 

organization’s website.119 Another 

commenter suggested a point system 

that would assign points (e.g., the ‘‘fire 

control group’’ would be three points, 

the hammer would be one point, and 


jspears on DSK121TN23PROD with RULES2
24694 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

the striker would be one point). Under 

this suggestion, the external part that 

has the most points would be the frame 

or receiver. 

While some commenters suggested 

ATF should just accept the 

manufacturer-designated component 

identified as ‘‘firearm’’ for each model, 

another commenter, SAAMI, suggested 

that, with respect to the AR–15 Colt 

Sporter, ATF could simply amend the 

existing regulation to specify that the 

lower receiver is the ‘‘frame or receiver’’ 

of that firearm. Another commenter 

suggested that frame or receiver should 

be defined as: ‘‘that portion of the 

weapon, that holds the fire control 

group, consisting of any of the 

following, trigger, sear, safety and 

hammer if the weapon is hammer 

fired.’’ According to the commenter, this 

would consistently mean the lower 

receiver and encompass all weapons, 

i.e., the lower on an AR–15, the lower 

on a Glock, the lower on a break open 

shotgun (not including barrel), the lower 

on a revolver, and the lower on a 

semiautomatic pistol would be the 

‘‘firearm’’ regardless of the striker fire or 

hammer fire (because it holds the trigger 

or sear). This, according to the 

commenter, would also encompass the 

side plate on certain machineguns. 

To address the cases in which ATF 

has not prevailed in litigation, one 

commenter suggested a more specific fix 

that would define frame or receiver as 

the ‘‘mounting point, housing structure, 

or the significant part thereof for a 

firearm’s barrel, barrels or barrel 

assembly since all guns have at least one 

barrel.’’ Or, to address that striker-fired 

mechanisms are not fully captured 

under the current law, commenters said 

the definition could be easily amended 

to ‘‘that part of a firearm which provides 

housing for the hammer or striker, bolt 

or breechblock, and firing mechanism, 

and which is usually threaded at its 

forward portion to receive the barrel.’’ 

Department Response 

The Department agrees with 

commenters who stated that ATF’s 

current definition of ‘‘frame or receiver’’ 

is outdated and confusing, and that the 

proposed definition should be 

simplified. For this reason, ATF is 

providing a new regulatory definition of 

‘‘frame or receiver’’ to encompass 

existing and new firearm designs. The 

GCA and NFA do not define the term 

‘‘frame or receiver,’’ so only the 

regulatory definitions of that term in 27 

CFR parts 478 and 479 are being 

redefined. For the reasons previously 

discussed, the Department agrees that a 

more concise, less complex definition 

that focuses on a single part of each 

weapon is preferable, and will adopt a 

definition of ‘‘frame’’ with respect to 

handguns and ‘‘receiver’’ with respect to 

rifles, shotguns, and projectiles weapons 

other than handguns. 

The Department disagrees with 

commenters who suggested amending 

the current definitions of ‘‘frame or 

receiver’’ by replacing ‘‘and’’ with ‘‘or’’ 

as the conjoiner with respect to the 

listed components of the current 

definition. Under this alternative, any 

part of a firearm that houses either the 

hammer, or a bolt or breechblock, or a 

firing mechanism, or that receives the 

barrels would be considered frames or 

receivers. Thus, under this alternative, 

there could exist even more firearm 

parts that would constitute a ‘‘frame or 

receiver’’ than identified by the 

proposed rule. This alternative also does 

not identify a single ‘‘receiver’’ in 

numerous split receiver firearms. In an 

AR–15-type rifle, for example, the 

hammer, firing mechanism, and forward 

portion that receives the barrel are all in 

the lower receiver, but the bolt or 

breechblock is in the upper receiver. 

The same problem exists when applying 

SAAMI’s definition from its Glossary of 

Industry Terms because the firing and 

breech mechanisms are not in the same 

‘‘receiver.’’ While the lower receiver 

houses the firing mechanism and is 

attached to the stock, the upper receiver 

houses the breechblock and is attached 

to the barrel. Therefore, under SAAMI’s 

published definition, in an AR–15-type 

firearm, for example, there would still 

be more than one part that would be 

defined as a ‘‘frame or receiver’’ on this 

weapon as well as on numerous split or 

modular models of firearms in common 

use today. This alternative definition 

also does not explain how it would 

apply to firearms that do not have a 

hammer, but are fired using a striker, 

which may be located in different 

housings depending on the type of 

firearm. 

The Department also disagrees with 

the point system recommended by one 

commenter because it does not explain 

how the point values were reached, and 

why fire control components in other 

portions of the assembled weapon were 

not assigned any points. It would not 

address firearms that do not house all 

‘‘fire control group’’ components within 

a single housing, or which have a 

remote trigger outside the weapon. In 

sum, this alternative would fall short of 

addressing all technologies or designs of 

firearms that are currently available, or 

may become available in the future. It 

also does not address potential changes 

in firearms terminology. 

The Department agrees with SAAMI 

on expressing in the final rule that the 

lower receiver of the AR–15 Colt Sporter 

(and variants thereof) is the ‘‘receiver’’ 

of that weapon. The final rule also 

includes a diagram of the AR–15 

receiver. The Department will also 

grandfather all prior ATF classifications 

specifying which single component of a 

weapon is its frame or receiver. 

However, the Department will not 

grandfather ATF determinations that a 

partially complete, disassembled, or 

nonfunctional frame or receiver, 

including a parts kit, was not, or did not 

include, a firearm ‘‘frame or receiver’’ as 

defined prior to this rule, including 

those where ATF determined that the 

item or kit had not yet reached a stage 

of manufacture to be one. In any event, 

simply specifying that the lower 

receiver of the AR–15 Colt Sporter is a 

‘‘receiver’’ does not solve the problem of 

defining the term ‘‘frame or receiver’’ 

with respect to all of the firearms with 

a split or multi-piece frame or receiver, 

or those that are striker fired. The 

problem remains that a court could 

decide that the current definition of 

‘‘frame or receiver’’ does not apply to 

those firearms. Thus, the existing 

definition is not adequate with respect 

to the vast majority of firearms currently 

in the United States. 

The Department declines to accept the 

proposed alternative definition saying 

that a ‘‘frame or receiver’’ is the portion 

of a weapon ‘‘that holds the fire control 

group, consisting of any of the 

following, trigger, sear, safety and 

hammer, if the weapon is hammer 

fired.’’ First, some firearms may be 

initiated manually by hand or ‘‘slam 

fired’’ without a part that actually holds 

a trigger, sear, safety, and hammer, and 

all complete, assembled weapons must 

have a frame or receiver. Second, not all 

of these fire control components may be 

in the same portion of the weapon, and 

some fire control groups, or portions 

thereof, may be found outside the frame 

or receiver, or triggered remotely. 

Nonetheless, the final rule accepts this 

alternative insofar as the ‘‘frame’’ of a 

handgun will be defined as the part that 

provides housing for the primary 

energized component designed to hold 

back the hammer or striker, which is 

generally the ‘‘sear.’’ 

The Department also declines to 

accept the proposed alternative 

definition saying that the frame or 

receiver is the ‘‘mounting point, housing 

structure, or the significant part thereof 

for a firearm’s barrel, barrels or barrel 

assembly since all guns have at least one 

barrel.’’ This suggested definition would 

be inconsistent with what ATF and the 

firearms industry have understood to be 

the frame or receiver of numerous 

semiautomatic handguns, such as Glock 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24695 

and Sig Sauer pistols and variants 

thereof, which is the lower portion of 

the weapon housing the sear, trigger 

mechanism, and other fire control parts. 

In such handguns, the barrel is housed 

in the upper slide. This suggested 

definition would, therefore, create 

confusion for many firearm 

manufacturers. 

The new definitions in this rule are 

intended to describe the specific part of 

weapons that has traditionally been 

considered the frame or receiver for 

almost all firearms, but are general 

enough to accommodate future designs 

and changes in parts terminology. The 

few exceptions, such as the AR–15 rifle 

and Ruger Mark IV pistol, are 

grandfathered into the new definitions 

of those terms and may continue to be 

marked in the same manner as they 

have been prior to the effective date of 

this rule. 

The Department acknowledges 

comments that stated that the current 

definition does not include a housing 

for ‘‘striker’’ fired weapons. The new 

definitions, which focus on the housing 

or structure for a single fire control 

component (i.e., sear or equivalent for 

handguns, and bolt, breechblock, or 

equivalent for all other projectile 

weapons), are broad enough to cover 

both striker and hammer-fired weapons. 

e. Definition of ‘‘Firearm Muffler or 

Silencer Frame or Receiver’’ 

Comments Received 

Some commenters opposed the 

proposed definition of ‘‘complete 

muffler or silencer device,’’ stating that 

the new definition would subject 

persons who possess a complete but 

disassembled silencer to the civil and 

criminal penalties associated with 

possession of a complete silencer. They 

also objected to frames or receivers of 

silencer devices, which may not be in 

an operational state, becoming subject to 

the new ‘‘readily’’ factors test used to 

establish the scope of weapon parts kits 

and firearm frame or receiver regulation. 

One manufacturer also pointed out that 

the definition of complete silencer 

device does not appear to include a 

silencer that uses a firearm-mounted 

flash-hider or other attachment devices 

for use if the mounting device is not 

included with or attached to the 

silencer. 

Separately, while some commenters 

noted that the proposed definition of 

‘‘firearm muffler or silencer frame or 

receiver’’ is an improvement on current 

law, there remains confusion regarding 

whether ATF intends for only a singular 

part to be the frame or receiver for 

firearm silencers. They stated that ATF 

should clarify in the final rule that 

firearm silencers only need to be 

marked on a single piece that is the 

frame or receiver. Another manufacturer 

raised a similar concern that under the 

proposed definition, a non-welded 

suppressor’s end cap appears to be a 

frame or receiver requiring serialization. 

The manufacturer gave an example of 

Ruger Silent-SR and Silent SR ISB 

silencers that use a traditional baffle 

stack of non-welded individual baffles 

housed in a serialized tube. When 

installed, the end cap secures the baffles 

in place within the tube. The end cap, 

in this instance, seems to be a frame or 

receiver because it ‘‘provides housing or 

a structure . . . designed to hold or 

integrate one or more essential internal 

components of the device.’’ They stated 

that this conclusion, if accurate, would 

mean that a majority of suppressors 

utilizing a non-welded design have 

more than one frame or receiver, 

contrary to ATF’s position. 

The same manufacturer also raised 

concerns about ATF’s attempt to 

memorialize the longstanding policy 

regarding silencer parts transferred 

between qualified individuals. The 

proposed rule allowed such transfers on 

the condition that ‘‘upon receipt, [the 

parts are] actively used to manufacture 

a complete muffler or silencer device.’’ 

The manufacturer argued that this 

section does not seem to allow a 

qualified manufacturer to send 

unmarked suppressor components to 

another qualified manufacturer for 

further manufacturing activities (e.g., 

machining, coating, etc.) if the parts are 

not going to be assembled into a 

complete muffler or silencer device by 

the subcontractor manufacturer. 

Because ‘‘actively’’ is not defined, the 

commenting manufacturer stated it was 

unclear if it could transfer a large 

quantity of suppressor parts to a 

subcontractor to be consumed as needed 

by the manufacturer to make complete 

suppressors over an extended period. 

Department Response 

As stated previously, the Department 

agrees with commenters that the term 

‘‘frame or receiver’’ is best read to mean 

a singular frame or receiver that must be 

identified with a single unique serial 

number. This would include the frame 

or receiver of a complete firearm muffler 

or silencer device. The Department also 

agrees with the comment that an end 

cap of an outer tube or modular piece 

could have been considered a structural 

component within the meaning of a 

frame or receiver as proposed. End caps 

are often damaged or destroyed upon 

expulsion of projectiles, leaving the 

muffler or silencer without any 

traceable markings of identification. For 

this reason, the Department is amending 

the definition of those terms in the final 

rule as follows: ‘‘in the case of a firearm 

muffler or firearm silencer, the part of 

the firearm, such as an outer tube or 

modular piece, that provides housing or 

a structure for the primary internal 

component designed to reduce the 

sound of a projectile (i.e., baffles, 

baffling material, expansion chamber, or 

equivalent). In the case of a modular 

firearm muffler or firearm silencer 

device with more than one such part, 

the terms shall mean the principal 

housing attached to the weapon that 

expels a projectile, even if an adapter or 

other attachments are required to 

connect the part to the weapon. The 

terms shall not include a removable end 

cap of an outer tube or modular piece.’’ 

The Department also agrees with the 

commenter who stated that the 

proposed provision concerning transfers 

of firearm mufflers or silencers between 

qualified licensees could be read to 

exclude further manufacturing 

activities, such as further machining or 

applying protective coatings. For this 

reason, the Department has removed the 

term ‘‘actively,’’ and, instead, explained 

that mufflers or silencers must be 

marked by close of the next business 

day after the entire manufacturing 

process has been completed. The 

Department has also made minor 

amendments to the marking allowances 

to make clear that mufflers or silencers 

may be transferred between qualified 

manufacturers for further manufacture 

(i.e., machining, coating, etc.) without 

immediately identifying and registering 

them. Once the new device with such 

part is completed, the manufacturer of 

the device must identify and register it 

in the manner and within the period 

specified in this part for a complete 

muffler or silencer device. 

f. Definition of ‘‘Split or Modular Frame 

or Receiver’’ 

Comments Received 

With respect to ATF classifying the 

frame or receiver of a split or modular 

frame or receiver, numerous 

commenters objected to the definition 

not only on the grounds that it was too 

broad and confusing, but that to obtain 

certainty, it was largely dependent on 

ATF making classifications. They 

critiqued this process as lacking 

transparency, objectivity, and efficiency, 

as well as placing too much power in 

the hands of ATF. Numerous 

commenters said they introduce new 

models multiple times per year, and 

assuming a new determination is 

needed for each new model or 


jspears on DSK121TN23PROD with RULES2
24696 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

configuration, they have serious 

concerns that classification process 

would bury them in red tape. They 

stated the lead time, which is currently 

6–12 months or more, would be much 

longer if hundreds of manufacturers 

were submitting to determine which 

component qualifies as the receiver, and 

this would be costly and disruptive to 

their companies. Due to the current 

delays in obtaining classifications, one 

commenter suggested the proposal 

could discourage classification requests 

rather than encourage them. 

Several industry members stated that 

the firearm specific definitions under 

‘‘split or modular frame or receiver’’ are 

confusing. It is not clear if the 

definitions apply only to firearms 

produced by those manufacturers listed 

or if it applies to all firearms that follow 

the same basic design. The confusion, 

they stated, is evident in the first of 

these definitions for ‘‘Colt 1911-type, 

Beretta/Browning/FN Herstal/Heckler & 

Koch/Ruger/Sig Sauer/Smith & Wesson/ 

Taurus hammer fired semiautomatic 

pistols.’’ They questioned if the 

definition applies only to hammer-fired 

semiautomatic pistols manufactured by 

these discrete manufacturers or applies 

to all firearms that integrate an 

operating system that matches ATF’s 

provided definition for these firearms. 

Similarly, they stated ATF’s use of ‘‘- 

type’’ was unclear and asked, for 

instance, if ‘‘Sig Sauer P320-type 

semiautomatic pistols’’ is meant to 

include only P320s or exact replicas 

thereof, or if it is meant to convey a 

broader meaning of any firearm that has 

the same basic design, even if it uses 

different materials or has different gross 

dimensions (such as the Sig P365). 

Additionally, commenters stated the 

nonexclusive lists used in definitions 

for frame or receiver indicated that there 

are other firearms designs and 

configurations not listed that fall into 

the category of ‘‘-type’’ but that are 

unknown to the public. Commenters 

also questioned what ATF meant by 

‘‘comparable’’ when the NPRM 

explained that split or modular firearm 

designs that are not comparable to an 

existing classification would not be 

grandfathered in under the rule, thus 

making it possible that more than one 

part of the firearm would be the ‘‘frame 

or receiver’’ under the proposed 

definition. 

Numerous commenters noted that 

several models of firearms were missing 

from the list of examples under the 

supplemental definition of frame or 

receiver entitled ‘‘split or modular frame 

or receiver’’ and that without clearer, 

more articulate lists, it appears that 

several models would be subject to more 

marking requirements. One commenter, 

an FFL/SOT, expressed that the 

examples provided in the definitions do 

not include the most widespread and 

popular 22LR pistols such as the Ruger 

Mark I/II/III/IV, Browning Buckmark, 

S&W Model 41, and similar designs. 

They stated that millions of these have 

been sold over the past 70 years with 

the serialized firearm component 

varying between models from the 

assembly containing the barrel to the 

assembly containing the trigger 

mechanism. Without addressing these 

models, the comment said it is not clear 

where serialization should occur. 

Similarly, another commenter 

provided examples of three models—the 

512 Remington ‘‘Sportmaster’’ .22 

rimfire bolt action tubular repeater, the 

9422 Winchester .22 rimfire lever action 

repeater, and the 1911 and 1911A series 

Colt—and listed several parts of each 

firearm that the commenter believes 

would be subject to the marking 

requirements under the proposed 

definition. The FN PS90 firearm was 

another model raised as to which a 

commenter did not understand how the 

new definition would apply. The 

commenter stated that the upper of the 

FN PS90 is the serialized component 

and that the stock assembly (made 

entirely out of plastic) is a stock. Under 

the NPRM’s definition, the commenter 

stated that the stock would need to be 

serialized because it is made of two 

externally visible parts bolted together. 

Therefore, the commenter questioned 

whether each half of the stock would 

require its own serial number or if the 

parts would need to have injection 

molding done by a Type 07 licensee. 

Another commenter opined that the 

example for AK-type firearms is not 

consistent with many existing AK-type 

firearms already lawfully possessed. 

The commenter stated that while many 

of these firearms are marked on the 

identified ‘‘single receiver,’’ many of 

these types of firearms have been 

imported with the serial number only 

marked on the front trunnion. Thus, the 

commenter asked that this example be 

re-evaluated since it is unlikely ATF is 

intending to identify an unmarked part 

of thousands of firearms. Other 

commenters similarly said that ATF 

made an error when it listed the frame 

or receiver for a Beretta AR–70 type as 

the lower receiver because under 

existing precedent, the upper receiver of 

the AR–70 has been treated as the frame 

or receiver. 

Finding the nonexclusive lists of 

frame or receiver examples to be 

inadequate and likely to lead to 

confusion or resulting in thousands of 

unnamed firearm types that will, by 

default, have multiple frames or 

receivers, other commenters said ATF 

should make all known or existing 

classifications public or listed in the 

final rule. It is, they argued, the only 

way to ensure fairness. 

Department Response 

The Department agrees with 

numerous commenters that the 

supplement to the definition entitled 

‘‘split or modular frame or receiver’’ 

would have been difficult for persons to 

apply under the proposed definition of 

‘‘frame or receiver’’ that meant a 

housing for any fire control component. 

Additionally, the Department 

acknowledges commenters’ concerns 

that many models of firearms were not 

included, and that the proposed 

definition could lead persons to submit 

new classification requests rather than 

relying on the definition to identify the 

frame or receiver. 

The Department, in response to these 

comments, is finalizing a definition of 

‘‘frame or receiver’’ in a new § 478.12 

that incorporates limited subsets of the 

proposed definition while providing 

distinct definitions for ‘‘frame’’ and 

‘‘receiver.’’ The new definitions under 

‘‘frame or receiver’’ focus on only one 

housing or structural component for a 

given type of weapon. Because the final 

rule focuses on a single component 

based on the recommendations of 

commenters, there is no longer a need 

for the supplement entitled ‘‘split or 

modular frame or receiver,’’ and it is not 

adopted in the final rule. The 

Department also acknowledges that the 

lower portion of the AR–70 was 

mistakenly identified as the receiver of 

that firearm in the NPRM. Under the 

final rule, the upper portion of the AR– 

70 remains the receiver of that firearm 

as described by the new definition of 

‘‘receiver.’’ 

Furthermore, to ensure that industry 

members and others can rely on ATF’s 

prior classifications, most prior ATF 

classifications, and variants thereof, 

have been grandfathered into the new 

definition of ‘‘frame or receiver’’ along 

with examples and diagrams of some of 

those weapons, such as the AR–15 rifle 

and Ruger Mark IV pistol. The only 

exceptions are classifications of 

partially complete, disassembled, or 

nonfunctional frames or receivers that 

ATF had determined did not fall within 

the definition of firearm ‘‘frame or 

receiver’’ prior to this rule. Any such 

classifications, including parts kits, 

would need to be resubmitted for 

evaluation. If persons remain unclear 

which specific portion of a weapon or 

device falls within the definitions of 

‘‘frame’’ or ‘‘receiver,’’ then they may 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24697 

120See footnote 78, supra. 

121See 18 U.S.C. 922(a)(5); Cal. Penal Code 

27545; Colo. Rev. Stat. 18–12–112(2)(a); Conn. Gen. 

Stat. 29–36l(f), 29–37a(e)(2); D.C. Code Ann. 7– 

2505.02(a); Del. Code. tit. 11 1448B(a); 430 ILCS 65/ 

3(a–10); Md. Code, Public Safety 5–204.1(c)(1); Nev. 

Rev. Stat. 202.2547(1); N.J. Stat. Ann. 2C:58–3(b)(2); 

N.M.S.A. 30–7–7.1(A)(2); N.Y. Gen. Bus. Law 

898(2); Or. Rev. Stat. 166.435(2); 18 Pa. C.S.A. 

6111(c); Vt. Stat. Ann. tit. 13, 4019(b)(1); Va. Code 

An. 18.2–308.2:5(A); Rev. Code Wash. 9.41.113(3). 

voluntarily submit a request to ATF as 

provided in this rule. 

g. Alternative for Defense Industry 

Under ‘‘Split or Modular Frame or 

Receiver’’ 

Comments Received 

Another commenter who represents 

members of the defense manufacturing 

industry suggested including as an 

example (‘‘box-type’’) of a split frame or 

receiver for which a single part had 

been previously classified by the 

Director ‘‘externally powered weapons.’’ 

The commenter explained as follows: 

Some externally powered designs 

include a part called the ‘‘front 

housing’’ that directly attaches to the 

existing frame or receiver and houses 

the breech. The front housing positions 

the breech to align with the bolt, which 

in turn, allows the bolt assembly to 

properly lock and drop the firing pin 

when the barrel is installed. Under the 

proposed definition, the commenter 

observed, it appears that this ‘‘front 

housing’’ could include this and other 

parts of the weapon not previously 

understood to be the frame or receiver, 

in addition to the existing ‘‘bathtub’’ or 

box-type receiver. As an alternative, the 

commenter suggested adding language 

that would exempt ‘‘externally powered 

weapons’’ that require ‘‘a separate 

electronic gun control unit to fire, and 

which [are] used solely in a government 

military platform, simulation, or 

training exercise, and where the 

weapon’s design does not have a 

civilian surrogate,’’ from either the 

definition of ‘‘partially complete’’ 

frames or receivers or ‘‘readily.’’ 

As a completely different alternative, 

the same commenter requested that ATF 

include a simple annual notification 

procedure where qualified defense 

importer and manufacturer licensees 

could prove that they meet ‘‘opt out’’ 

requirements of the proposed rule and 

proceed with their processes under the 

existing regulatory requirements. The 

commenter suggested an ‘‘opt out’’ 

provision because the increased 

compliance obligations of the proposed 

rule would further complicate an 

already challenging workflow and 

impede contractual deadlines the 

commenter’s clients have with the U.S. 

Government. 

Department Response 

The Department declines to adopt the 

commenter’s suggestion to add ATF’s 

classification of ‘‘externally powered 

weapons.’’ As described above, the final 

rule grandfathers most prior ATF 

classifications and variants thereof, 

including ‘‘box-type’’ or externally 

powered weapons, into the new 

definition of ‘‘frame or receiver’’ along 

with examples and a diagram of those 

weapons. The Department also declines 

to adopt the suggestion allowing 

qualified defense importer and 

manufacturer licensees to opt out from 

the proposed rule and proceed with 

their processes under the existing 

regulatory requirements. The GCA, 18 

U.S.C. 925(a), does not exempt the 

manufacture of firearms for the 

government from the licensing, marking, 

and other requirements imposed on 

manufacturers. It only exempts the 

transportation, shipment, receipt, 

possession, or importation of firearms 

sold or shipped to, or issued for the use 

of, the government. Otherwise, 

unmarked, untraceable firearms 

manufactured for the government could 

be lost or stolen without any ability to 

trace them if later involved in crime. 

h. Definition of ‘‘Partially Complete, 

Disassembled, or Inoperable Frame or 

Receiver’’ 

Comments Received 

Commenters opposed to inclusion of 

partially complete frames or receivers in 

the proposed definition of frame or 

receiver stated that the proposed rule 

would be difficult, if not impossible, to 

enforce. They opined that there is no 

purpose in trying to ‘‘ban 80%’’ 

receivers or regulate partially complete 

receivers because the rule is easily 

undercut by 3D-printing technology and 

the availability of online tutorials, 

which will only become more available 

and affordable for the public over time. 

One commenter, for example, stated 

that, even if all unfinished, or ‘‘80%,’’ 

receivers were taken away, firearms 

could still be made through other 

means, citing the FGC9 as an example. 

Because the commenter believes that 

technology undercuts the rule, the 

commenter argued that the new 

definitions and marking requirements 

serve no purpose and should not be 

adopted. 

Commenters also had several 

questions about the terms used in the 

definition of partially complete frame or 

receiver such as what it means for an 

item to cross the critical line to where 

it ‘‘reach[es] a stage of manufacture 

where it is clearly identifiable as an 

unfinished component part of a 

weapon.’’ Other commenters asserted 

that the definition lacks objectivity and 

there are no objective metrics to guide 

the factors that are listed. With the 

proposed changes, the commenters 

questioned the meaning of ‘‘functional 

state.’’ Similarly, although ATF stated in 

the preamble that unformed blocks of 

metal or articles in a primordial state 

‘‘without more’’ would not be 

considered a partially complete frame or 

receiver, commenters stated that it is 

still unclear when these items fall under 

the definition where, for example, there 

were instruction booklets, metal 

working tools, or tutorial videos, 

because the definition hinges on what 

‘‘without more’’ means, which ATF did 

not explain. 

Manufacturers also raised concerns 

because they purchase partially 

machined raw materials or receiver 

shells without drilled fire control holes 

from domestic and foreign sources that 

are not current licensees. The 

manufacturers were concerned that the 

proposed rule would subsequently 

require their suppliers to obtain an FFL 

license, apply the markings, and keep 

A&D records, which would be very 

costly and disruptive. Another 

commenter suggested that ‘‘critical stage 

of manufacture’’ should be amended to 

say: ‘‘when the article becomes 

sufficiently complete to function as a 

frame or receiver.’’ 

Department Response 

The Department disagrees with 

commenters who stated that inclusion 

of partially complete frames or receivers 

in the proposed definition of frame or 

receiver would be difficult, if not 

impossible, to enforce. The proposed 

and final rule both make clear that a 

partially complete frame or receiver 

must have reached a stage of 

manufacture where it is clearly 

identifiable as a component part of 

weapon to be classified as a potential 

frame or receiver. Such articles have 

been regulated for importation and 

exportation since at least 1939.120 With 

regard to 3D-printed PMFs, this rule 

explains that, as technology progresses, 

PMFs are likely to make their way to the 

licensed community because firearms 

licensees are likely to market them for 

sale, accept them into pawn, or repair 

them through gunsmithing services. 

Additionally, the GCA requires out-ofState firearm transfers to go through 

licensees, and some States require 

firearm sales or transfers to be 

conducted through licensees.121

However, the Department agrees with 

commenters that the supplement to the 


jspears on DSK121TN23PROD with RULES2
24698 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

122 ‘‘Nonfunctional’’ is more accurate because, 

although the weapons in which they are 

incorporated are ‘‘operated’’ by a shooter, frames or 

receivers are not operated by a person. Rather, 

frames or receivers are better described as 

‘‘functional’’ or ‘‘nonfunctional’’ in that they may 

or may not be in a state of completion where they 

can house or hold the fire control components that 

allow the shooter to operate the weapon. 123See footnotes 43 and 44, supra. 

124See ATF, How to Properly Destroy Firearms 

(Aug. 14, 2019), available at https://www.atf.gov/ 

firearms/how-properly-destroy-firearms; ATF Rul. 

2003–1 (destruction of Browning M1919 type 

receivers); ATF Rul. 2003–2 (FN FAL type 

receivers); ATF Rul. 2003–3 (Heckler & Koch G3 

type receivers); ATF Rul. 2003–4 (Sten type 

receivers). 

proposed definition of ‘‘frame or 

receiver’’ entitled ‘‘partially complete, 

disassembled, or inoperable frame or 

receiver’’ should be revised to provide 

more guidance on the application of the 

definition. In the final rule, the 

Department has: (1) Removed the 

definition of ‘‘partially complete’’ as it 

modified the term ‘‘frame or receiver’’ 

and, instead, has expressly excluded 

from the definition of ‘‘frame or 

receiver’’ forgings, castings, printings, 

extrusions, unmachined bodies, or 

similar articles that have not yet reached 

a stage of manufacture (e.g., unformed 

blocks of metal, liquid polymers, or 

other raw materials) where they are 

clearly identifiable as an unfinished 

component part of a weapon; (2) made 

related clarifying amendments, such as 

changing the term ‘‘inoperable’’ to the 

more accurate term ‘‘nonfunctional,’’ 122

and expressly stating that the section 

includes frame or receiver parts kits that 

are designed to be—or may readily be— 

completed, assembled, restored, or 

otherwise converted to a functional 

state; (3) explained the meaning of the 

term ‘‘functional state’’ to be a frame or 

receiver that houses or provides a 

structure for the primary energized 

component of a handgun, breech 

blocking or sealing component of a 

projectile weapon other than a handgun, 

or internal sound reduction component 

of a firearm muffler or firearm silencer, 

as the case may be; and (4) included 

detailed examples of what would and 

would not be considered a ‘‘frame or 

receiver’’ that may readily be 

completed, assembled, restored, or 

otherwise ‘‘converted’’ to a functional 

state. Thus, as the proposed rule 

explained, articles that are not clearly 

identifiable as component parts of a 

weapon cannot be considered frames or 

receivers. See 86 FR at 27729. And even 

articles that are clearly identifiable as a 

partially complete, disassembled, or 

nonfunctional frame or receiver of a 

weapon are not frames or receivers 

under the new definitions unless they 

are designed to function as a frame or 

receiver, or may readily be completed, 

assembled, restored, or otherwise 

converted to do so. 

The Department disagrees with the 

comment that the supplement should be 

amended to say that a frame or receiver 

means one that has reached a stage in 

manufacture ‘‘when the article becomes 

sufficiently complete to function as a 

frame or receiver.’’ The GCA does not 

explain when an article becomes 

sufficiently complete to be a frame or 

receiver. As stated previously, to 

determine when a frame or receiver is 

created, this rule is guided by the 

definition of ‘‘firearm’’ in section 

921(a)(3)(A), the definition of 

‘‘machinegun’’ in 26 U.S.C. 5845(b), and 

relevant case law interpreting when a 

weapon ‘‘may readily be converted to 

expel a projectile by the action of an 

explosive’’ and ‘‘can readily be restored 

to shoot.’’ 123 This rule adopts these 

statutory concepts and case law so that 

ATF’s regulations more plainly indicate 

that a clearly identifiable component 

part of a weapon becomes a frame or 

receiver when it may readily be 

completed, assembled, restored, or 

otherwise ‘‘converted’’ to function as a 

frame or receiver, i.e., to house or 

provide a structure for the primary 

energized component of a handgun, 

breech blocking or sealing component of 

a projectile weapon other than a 

handgun, or internal sound reduction 

component of a firearm muffler or 

firearm silencer, as the case may be. 

i. Definition of ‘‘Destroyed Frame or 

Receiver’’ 

Comments Received 

A few commenters opined on the 

proposed definition of ‘‘destroyed frame 

or receiver,’’ which would not be 

considered a frame or receiver under the 

definition. Some stated that the 

definition for ‘‘destroyed frame or 

receiver’’ contradicts the definition for 

‘‘partially complete, disassembled, or 

inoperable frame or receiver’’ because, 

according to the commenters, they are 

both in the same state as not being 

operable to create a working firearm and 

therefore ATF cannot regulate them as 

frames or receivers while also excluding 

them from the definition. Another 

commenter disagreed with ATF’s 

requirement that a cutting torch needs 

to be used to sever at least three critical 

areas of the frame or receiver to be an 

acceptable method of destruction. The 

commenter stated that, for polymer 

frames or receivers, simply cutting the 

frame or receiver in three critical areas 

should be enough because it could 

never be repaired by a reverse process 

and that a cutting torch is unnecessary 

to permanently destroy polymer frames. 

Department Response 

The Department disagrees that the 

definitional supplement concerning 

destroyed frames or receivers 

contradicts the supplement entitled 

‘‘partially complete, disassembled, or 

inoperable’’ (now ‘‘nonfunctional’’) 

‘‘frame or receiver.’’ Under that 

supplement, a partially complete, 

disassembled, or nonfunctional frame or 

receiver is considered a ‘‘frame or 

receiver’’ if it is designed to, or may 

readily be converted to, expel a 

projectile by the action of an explosive. 

That supplement does not address 

destruction, which is addressed in the 

supplement entitled ‘‘destroyed frame 

or receiver.’’ A destroyed frame or 

receiver is one that has been 

permanently altered such that it may 

not readily be completed, assembled, 

restored, or otherwise converted to 

function as a frame or receiver. That 

supplement further explains how 

destruction may be accomplished— 

completely melting, crushing, or 

shredding the frame or receiver, or other 

method approved by the Director. The 

torch cut method in the proposed rule 

was cited only as one acceptable 

method, but it is not the only 

method.124 To avoid confusion on this 

issue, the final rule replaces the stated 

methods with ‘‘or other method 

approved by the Director.’’ 

j. Definition of ‘‘Readily’’ 

Comments Received 

Numerous commenters criticized the 

proposed definition of ‘‘readily,’’ which 

would be relied upon to determine, in 

part, if a partially completed frame or 

receiver falls under the definition of 

‘‘frame or receiver’’ or if a weapon parts 

kit falls under the definition of 

‘‘firearm.’’ The overwhelming concern 

raised was that the definition of 

‘‘readily’’ is a nonexclusive list of 

numerous factors, none of which is 

controlling, and which includes 

subjective considerations that could 

leave it unclear to the industry and 

public when an item meets any 

particular definition. Commenters, for 

instance, explained that parts could be 

a firearm if an expert using specialized 

tools assembled it in ten minutes if ATF 

were to focus on the factors of time and 

ease; alternatively, those same parts 

assembled in that scenario might not be 

a firearm if ATF were to focus on the 

factors of expertise and equipment. 

Similarly, others argued that all the 

terms were impermissibly vague or 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24699 

arbitrary. For example, these 

commenters stated that ‘‘expertise’’ is 

wholly subjective and that ATF did not 

identify what knowledge or skills are 

essential to making a firearm. 

One trade group stated that several 

major manufacturers communicated that 

as many as seven or more stages of a 

pistol’s receiver construction could be 

called into question under the proposed 

definition because it is not clear when 

a frame or receiver is ‘‘readily 

completed.’’ Each stage of the process, 

the group argued, could require 

serialization and recordkeeping. The 

group said that changing the standard of 

requiring serialization from only 

finished products to those that are 

‘‘readily completed’’ is confusing to 

both manufacturers and their suppliers. 

Additionally, as mentioned above, 

manufacturers expressed concern that 

the products they receive from nonlicensed third-party suppliers could fall 

under the definition of ‘‘partially 

complete.’’ 

Various commenters argued that 

expansive definitions of ‘‘readily,’’ 

when applied to a partially complete 

frame or receiver, could result in steel 

or aluminum billets, castings, forgings, 

or even simple glass reinforced nylon 

raw materials being considered firearms. 

Numerous commenters focused on the 

factor of ‘‘time’’ under the proposed 

definition of ‘‘readily,’’ arguing that it is 

not an adequate factor, without more 

specificity, by which to measure if a 

weapon parts kit or partially completed 

frame or receiver may be readily 

convertible or assembled into a firearm. 

Commenters pushed back against ATF’s 

reliance on some of the court cases ATF 

cited as support for the factors to define 

the term ‘‘readily.’’ They stated several 

of the cases are from the 1970s and 

discuss a wide range of what constitutes 

readily convertible, ranging from 12 

minutes, to 1 hour, to an 8-hour working 

day in a ‘‘properly equipped’’ machine 

shop. Thus, what one expert may 

accomplish easily in 20 minutes may 

require hours of hard work for a novice. 

One manufacturer, Polymer80, also 

critiqued ATF for not supplying a 

metric for time and for stating in a 

footnote that Polymer 80 assembly 

could be completed in under 30 

minutes, leaving the company to 

wonder if 30 minutes is the standard. 

One commenter suggested that eight 

hours of work would be a reasonable 

threshold. 

Some commenters believed that 

ATF’s own rulings and public 

statements in cases such as California v. 

ATF, mentioned above, contradict the 

notion that it is easy to finish lower 

receivers with simple possession of 

hand tools in a way that would bring 

them under the definition of ‘‘frame or 

receiver.’’ Commenters argued that the 

process of converting an unfinished 

lower receiver into a finished lower 

receiver requires specialized equipment, 

precision tools, skill, and time. Users, 

according to the commenters, must 

purchase numerous parts and assemble 

them with care. Similarly, other 

commenters, under the assumption that 

an ‘‘80% lower receiver’’ would be 

included under the definition of 

partially complete frame or receiver, 

argued that this item ‘‘cannot fire blank 

cartridges, nor can it be ‘readily 

converted’ to do so,’’ because multiple 

holes have to be drilled and complex 

mechanical parts need to be attached. 

They stated that the AR–15 lower 

receiver is a ‘‘frame or receiver’’ once it 

becomes an integral component 

containing a fire control group and is 

attached via the takedown pins to the 

other components required to form a 

complete weapon in the AR–15 design 

pattern. 

Others pointed out technological 

advances, such as CNC machines, that 

can convert metal ingots into a 

functional firearm, thus raising the 

question of whether a CNC machine 

sold alongside the ingots would be 

considered a firearm. Similarly, 

commenters questioned whether a 3D 

printer shipped with filament and files 

of 3D representations of firearms would 

constitute a firearm under the readily 

convertible test. Further, according to 

one commenter, in a ‘‘properly 

equipped’’ machine shop today, it 

would not be uncommon for the shop to 

acquire a three-axis CNC machine with 

a fourth axis trunnion for less than 

$10,000 (Tormach PCNC 440 with 

microARC 4). Accordingly, the 

commenter argued that the existing case 

law upon which ATF relies does not 

serve to narrow and clarify the 

definition of ‘‘readily convertible.’’ 

Commenters asserted that no one can 

predict what ‘‘instructions, guides, 

templates, [and] jigs’’ the ATF Director 

will rely on in any given case. 

Commenters argued that ATF needs to 

remedy the definition with exact 

definitions of time, ease, expertise, 

equipment, availability, expense, and 

scope. 

Other commenters noted that the term 

‘‘readily’’ is used throughout the GCA in 

several contexts, including interstate 

transportation of firearms (18 U.S.C. 

926A) and for the importability of 

firearms generally recognized as 

particularly suitable or readily 

adaptable for sporting purposes (18 

U.S.C. 925(d)(3)). Commenters also 

noted that there are countless other uses 

of the term ‘‘readily’’ throughout ATF 

regulations, such as in 27 CFR 

478.92(a)(1)(i) (stating that ‘‘[t]he serial 

number must be placed in a manner not 

susceptible of being readily 

obliterated’’), or in 27 CFR 479.131 

(requiring that certain records be 

‘‘readily accessible for inspection at all 

reasonable times by ATF officers’’). The 

commenters asserted that ATF’s 

proposed definition will impact all 

these other places where the term 

‘‘readily’’ qualifies certain provisions 

and that ATF’s proposed nonexclusive 

list of factors would not provide clarity 

in those contexts, either. 

One commenter suggested that the 

term ‘‘readily’’ be removed from the 

proposed definition so it reads: ‘‘The 

term ‘frame or receiver’ shall include, in 

the case of a frame or receiver that is 

partially complete, disassembled, or 

inoperable, a frame or receiver that has 

reached a stage in manufacture where it 

is clearly identifiable by mechanical 

properties, material composition, 

geometry or function as an unfinished 

component part of a weapon. For 

purposes of this definition, the term 

‘partially complete,’ as it modifies 

‘frame or receiver’ means a forging, 

casting, printing, extrusion, machined 

body, or similar article.’’ 

Other commenters questioned 

whether ‘‘solvent traps,’’ which they 

asserted are legitimate devices and 

sometimes resemble silencers, would be 

considered readily convertible under 

the new regulations. Although some 

individuals file an ATF Form 1 under 

the NFA to make solvent traps silencers, 

the commenters stated that persons 

using solvent traps as actual solvent 

traps should be allowed to transfer them 

across State lines without violating the 

GCA or becoming subject to the NFA. 

Department Response 

The Department disagrees that the 

term ‘‘readily’’ and the related 

nonexclusive list of factors when 

classifying firearms should be removed 

from the rule. As stated previously, the 

term ‘‘readily’’ has been adopted to 

determine when a weapon is considered 

a ‘‘firearm’’ under 18 U.S.C. 

921(a)(1)(A), and also when the critical 

stage of manufacture has occurred in 

which an unfinished component part of 

a weapon becomes a ‘‘frame or receiver’’ 

under 18 U.S.C. 921(a)(3)(B). To explain 

the meaning of that term, this rule first 

sets forth a common dictionary 

definition of that term and then 

provides more clarity on how the term 

‘‘readily’’ is used to classify firearms by 

listing relevant factors that courts have 


jspears on DSK121TN23PROD with RULES2
24700 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

125See footnote 43, supra. 

126See footnote 79, supra. 127See footnote 78, supra. 128See Section IV.B.3.h, supra. 

adopted when making that 

determination.125

The Department disagrees that these 

factors should incorporate minimum 

time limits, percentages of completion, 

or levels of expertise, or otherwise 

create thresholds to determine when 

weapon or frame or receiver parts are 

‘‘readily’’ converted. Enumerating in 

this rule how each of the factors would 

apply to the manifold designs and 

configurations of firearms and 

aggregations of firearm parts now in 

existence, or to those that may be 

produced in the future, would be 

difficult, if not impossible. However, the 

Department agrees that more clarity as 

to how the term ‘‘readily’’ is applied 

would help address commenters’ 

concerns. In the final rule, the 

Department: (1) Expressly excludes from 

the definition of ‘‘frame or receiver’’ 

unformed blocks of metal, liquid 

polymers, and other raw materials; (2) 

changes the term ‘‘inoperable’’ to the 

more accurate term ‘‘nonfunctional’’; (3) 

expressly includes frame or receiver 

parts kits; (4) explains the meaning of 

‘‘functional state’’; and (5) provides 

detailed examples of when an 

unassembled or damaged frame or 

receiver, frame or receiver parts kit, or 

partially complete billet or blank, as the 

case may be, would be considered a 

‘‘frame’’ or ‘‘receiver’’ because it may 

readily be completed, assembled, 

restored, or otherwise converted to a 

functional state. Although it would 

indeed be difficult, if not impossible, for 

ATF to provide examples of every 

possible state of completion or 

configuration of weapons or weapon 

parts, the proposed definition provides 

clarity on how the term ‘‘readily’’ is 

applied to the definition of ‘‘firearm,’’ 

and numerous courts have upheld the 

application of that term in related 

criminal and civil cases against 

constitutional vagueness challenges.126

The Department disagrees that 

application of the term ‘‘readily’’ in this 

rule will require manufacturers to 

serialize and record frames or receivers 

in each stage of the manufacturing 

process. First, the final rule expressly 

excludes from the definition of ‘‘frame 

or receiver’’ forgings, castings, printings, 

extrusions, unmachined bodies, or 

similar articles that have not yet reached 

a stage of manufacture where they are 

clearly identifiable as unfinished 

component parts of a weapon, such as 

unformed blocks of metal, liquid 

polymers, and other raw materials. 

Thus, it is not until articles have been 

fashioned into unfinished frames or 

receivers that they are subject to the 

‘‘readily converted’’ standard. 

Manufacturers and importers should 

already know that these items have been 

regulated as ‘‘defense articles’’ for 

purposes of importation and exportation 

for many decades.127 Second, as the 

examples in the final rule illustrate, 

only once a frame or receiver blank or 

billet is produced for sale or distribution 

must a determination be made whether 

the seller or distributor of the item or kit 

provides, or makes available to the 

purchaser or recipient of the item or kit, 

an associated template, jig, or tool that 

would allow the purchaser or recipient 

of the billet or blank to complete the 

frame or receiver fairly or reasonably 

efficiently, quickly, and easily. 

Companies that sell or distribute only 

unfinished frame or receiver billets or 

blanks, and not any associated jigs, 

templates, or similar tools to the same 

customer are not required to be licensed 

or to mark those articles with 

identifying information. However, 

companies that sell or distribute firearm 

parts kits, jigs, templates, or tools to the 

same customer with partially complete 

frames or receivers allowing them to be 

efficiently, quickly, and easily 

converted into functional weapons or 

functional frames or receivers must be 

licensed; must apply identifying 

markings to the partially complete 

frames or receivers; and must record 

them as firearms in their required 

records. Finally, under this rule, 

licensed manufacturers who receive 

non-firearm billets or blanks are not 

required to mark them until after the 

entire manufacturing process has ended 

for the complete weapon, or for the 

frame or receiver to be sold, shipped, or 

distributed separately, as the case may 

be—seven days in the case of GCA 

firearms and by close of the next 

business day in the case of NFA 

firearms. 

The Department agrees with 

commenters who said that the term 

‘‘readily’’ has other applications in the 

statute and regulations that have 

nothing to do with the enumerated 

factors. For this reason, the Department 

has made minor changes to this 

definition in the final rule to make clear 

that this term can apply to any process, 

action, or physical state, and that the 

listed factors relate only to firearm 

classifications, as follows: ‘‘A term that 

describes a process, action, or physical 

state that is fairly or reasonably 

efficient, quick, and easy, but not 

necessarily the most efficient, speediest, 

or easiest process, action, or state. With 

respect to the classification of firearms 

under this part, factors relevant in 

making this determination include the 

following:’’. 

With regard to certain items marketed 

as ‘‘solvent traps,’’ the definition of 

‘‘firearm silencer’’ in 18 U.S.C. 

921(a)(24) means ‘‘any device for 

silencing, muffling, or diminishing the 

report of a portable firearm, including 

any combination of parts, designed or 

redesigned, and intended for use in 

assembling or fabricating a firearm 

silencer or firearm muffler, and any part 

intended only for use in such assembly 

or fabrication.’’ A so-called ‘‘solvent 

trap’’ that has been indexed for the 

purpose of allowing the end user to drill 

a hole for the passage of a projectile to 

diminish the report of a portable firearm 

is intended only for use in fabricating a 

silencer. It is, by definition, a ‘‘firearm 

silencer’’ without regard for the 

definition of the term ‘‘readily’’ or the 

application of the term ‘‘may readily be 

converted.’’ 

k. Definition of ‘‘Complete Weapon’’ 

Comments Received 

Some commenters argued that ATF’s 

definition of a ‘‘complete weapon’’ is 

illogical because it includes ‘‘a firearm 

that contains all component parts 

necessary to function as designed 

whether or not it is assembled or 

operable.’’ They objected to the 

inclusion of operability, stating that, if 

it is inoperable, it is not a weapon. They 

also objected to inclusion of an 

unassembled weapon, as they believed 

this inclusion would create tremendous 

enforcement uncertainty. Commenters 

asserted that law-abiding gun owners 

who legally own both AR rifles and 

pistols could be charged with a felony 

if they store their firearms unassembled. 

Other commenters stated that the 

definition of ‘‘complete weapon’’ only 

generates confusion because, in their 

view, a ‘‘firearm’’ would legally be a 

‘‘firearm’’ whether or not it is a 

‘‘complete weapon’’ under the NPRM. 

Department Response 

For the reasons previously discussed, 

the Department disagrees that 

inoperable or nonfunctional firearms are 

not ‘‘weapons,’’ and that the application 

of the definition of ‘‘firearm’’ to 

unassembled weapons creates 

enforcement uncertainty.128 Firearms 

manufacturing is a continuum from raw 

material to a functional item, and the 

term ‘‘complete weapon’’ is needed to 

explain when the frame or receiver of a 

weapon in the process of being 

manufactured must be identified and 

recorded as required by the regulations. 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24701 

Specifically, under this rule, frames or 

receivers of non-NFA weapons that are 

in the process of being manufactured as 

part of complete weapons may be 

marked and recorded by a licensed 

manufacturer up to seven days after the 

entire manufacturing process for the 

complete weapon has ended. Complete 

NFA weapons, consistent with the 

recordkeeping requirement in 27 CFR 

478.123(a) and Form 2 submission 

requirement in 27 CFR 479.103, must be 

marked by close of the next business 

day after manufacture. Such complete 

weapons may be sold in an 

unassembled configuration or may be 

inoperable due to poor workmanship or 

design. But the fact that a complete 

weapon is sold or distributed 

unassembled, or happens to be currently 

inoperable, does not remove the 

requirement for identifying markings to 

be placed on the frame or receiver. 

The term ‘‘complete weapon’’ is also 

used in the rule to explain that frames 

or receivers and other parts defined as 

‘‘firearms’’ that are not component parts 

of a complete weapon at the time they 

are sold, shipped, or disposed of must 

be marked with all required markings 

within the specified time limits from 

completion so they can be traced if lost 

or stolen. The term is also needed to 

explain what it means to 

‘‘conspicuously’’ mark firearms with 

serial number and other marks of 

identification. Markings must be 

unobstructed by other markings when 

the complete weapon is assembled. 

l. Definition of ‘‘Privately Made 

Firearm’’ 

Comments Received 

One organization stated that the 

definition of PMF, which does not 

include firearms made prior to October 

22, 1968 (unless remanufactured after 

that date), does not distinguish between 

a commercially made pre-1969 firearm 

and those made privately. The 

organization stated that sometimes one 

cannot tell if a firearm has had its serial 

number defaced or removed. As a result, 

according to the organization, dealers 

will decline to transfer or sell a firearm 

with no serial number without regard to 

whether it is a PMF. Further, an 

individual may or may not know, or can 

be wrong or mislead a dealer about, 

whether a particular weapon is a PMF 

or just an old firearm. Other 

commenters objected on grounds that 

thousands of gun owners who bought or 

made firearms before 1969 would 

become criminals because there is no 

way to tell if the firearms, which do not 

have serial numbers, were made before 

or after 1969. 

Department Response 

The Department agrees that the 

exclusion for pre-October 22, 1968, 

firearms from the definition of PMF 

does not distinguish between firearms 

that were commercially manufactured 

from those that were privately made 

because that definition refers to firearms 

produced by persons licensed under the 

GCA on or after that date. See 18 U.S.C. 

921(a)(10) (defining ‘‘licensed 

manufacturer’’ as a person licensed 

under the provisions of chapter 44 of 

title 18). To make this clear, the final 

rule adds the term ‘‘manufactured’’ to 

that exception. However, the 

Department disagrees that the preOctober 22, 1968, exclusion from the 

definition of PMF raises concerns 

because it is not difficult for licensees 

to know if a firearm, whether or not it 

is a PMF, was manufactured or made 

prior to October 22, 1968. First, preOctober 22, 1968, firearms in circulation 

generally have some marks of 

identification. PMFs, by definition, are 

not marked with a serial number placed 

by a person licensed as a manufacturer 

under the GCA at the time the firearm 

was produced. Regulations 

implementing the Federal Firearms Act 

of 1938 required all firearms 

manufactured after July 1, 1958, to be 

identified with the name of the 

manufacturer or importer, a serial 

number, caliber, and model. See 

Internal Revenue Service, Department of 

the Treasury, 23 FR 343 (Jan. 18, 1958). 

The only exception from marking the 

serial number and model requirements 

was for shotguns and .22 caliber rifles 

not subject to the NFA. Id. at 346. Thus, 

the name of the manufacturer and 

caliber would still be marked on all 

commercially produced weapons, even 

though this subset of GCA firearms may 

not display a serial number or model 

(though some will). Second, there are 

few firearms in circulation 

manufactured prior to 1969 that were 

not commercially produced. As the rule 

explains, only in the past few years has 

technology advanced to allow 

individuals to quickly and easily make 

their own firearms for personal use from 

parts kits or 3D printers. Third, if a 

person is in doubt about whether a 

particular firearm without any markings 

was manufactured or made prior to 

October 22, 1968, there are many 

licensee and nonlicensee experts who 

can evaluate the firearm and provide an 

expert opinion, including as to whether 

the serial number on the firearm has 

been altered or obliterated. 

Additionally, persons may voluntarily 

seek a determination from ATF as to 

whether a particular firearm is subject to 

regulation using the procedure provided 

in this rule. 

m. Definition of ‘‘Importer’s or 

Manufacturer’s Serial Number’’ 

Comments Received 

A few commenters stated that the new 

definition of ‘‘importer’s or 

manufacturer’s serial number,’’ which 

requires more information than under 

the current regulatory scheme, is 

confusing. They stated the term 

‘‘identification number,’’ which is part 

of the definition of ‘‘importer’s or 

manufacturer’s serial number,’’ is not a 

defined term, though it seems to be 

referring to what the industry 

understands to be an identification 

number. They pointed out the term 

‘‘serial number’’ is interchangeably used 

throughout the NPRM in different 

sections to mean both the identification 

number and the newly defined term. 

Department Response 

The Department agrees with these 

commenters that clarification should be 

made to the definition of ‘‘importer’s or 

manufacturer’s serial number.’’ First, 

the Department recognizes the 

confusion that could be generated 

because the proposed definition of 

‘‘importer’s or manufacturer’s serial 

number’’ stated: ‘‘When used in this 

part, the term ‘serial number’ shall mean 

the ‘importer’s or manufacturer’s serial 

number,’ ’’ while other parts of the 

proposed marking requirements in 

§§ 478.92 and 479.102 used the term 

‘‘serial number’’ to also refer to a 

number that would be placed after an 

FFL’s abbreviated license number. For 

this reason, the final rule clarifies the 

definition by defining it as the serial 

number placed by a licensee on a 

firearm, including any full or 

abbreviated license number, any such 

identification on a privately made 

firearm, or a serial number issued by the 

Director. It also specifies that, for 

purposes of 18 U.S.C. 922(k) and 27 CFR 

478.34, the term shall include any 

associated licensee name or licensee 

city or State placed on a firearm. The 

inclusion of the serial number and the 

associated licensee’s information as part 

of this definition means that these 

markings are protected by 18 U.S.C. 

922(k), which prohibits possession of a 

firearm with a removed, obliterated, or 

altered serial number. 

Because licensees have the option of 

marking the frame or receiver with 

either (1) a serial number and the 

manufacturer’s or importer’s city and 

State, or (2) a serial number beginning 

with its abbreviated license number and 

its name (or recognized abbreviation), 


jspears on DSK121TN23PROD with RULES2
24702 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

129As noted in the NPRM, this rule, consistent 

with § 478.124(a), does not require completion of an 

ATF Form 4473 or NICS background check when 

a PMF is marked as a firearm ‘customization’ when 

it is returned to the person from whom it was 

received. 86 FR at 27731. 

the final rule also makes minor changes 

in §§ 478.92(a) and 479.102(a). 

Specifically, in clarifying how a serial 

number may begin with an abbreviated 

license number as a prefix, these 

sections use the term ‘‘unique 

identification number’’ to properly 

describe the identifying information that 

would follow an FFL’s abbreviated 

license number or an identification 

number placed by the maker of a PMF. 

Further, the rule also makes clear that 

the identification markings (including 

any unique identification number) must 

be ‘‘legible,’’ meaning that they must 

use exclusively Roman letters and 

Arabic numerals, or solely Arabic 

numerals. 

Also, to avoid confusion in the 

regulations with the ‘‘serial number’’ 

marked on a firearm, the term 

‘‘transaction number’’ was substituted 

for ‘‘serial number’’ when explaining: 

(1) How Federal Firearm License 

numbers are assigned in § 478.47(a); and 

(2) how ATF Forms 4473 may be 

ordered and recorded in §§ 478.122(b), 

478.123(b), and 478.125(e). This will 

ensure that the sequential number stated 

on the FFL or Form 4473 will not be 

confused with the ‘‘serial number’’ 

marked on a firearm. Future versions of 

Form 4473 will reflect this change to the 

regulations. 

n. Definition of ‘‘Gunsmith’’ 

Comments Received 

Several commenters who identified as 

gunsmiths expressed concern about 

ATF Ruling 2010–10 being superseded 

upon the effective date of the final rule. 

ATF Ruling 2010–10 allows Type 01 

gunsmiths to perform various services 

for manufacturers and importers 

without needing to mark the firearm (or 

frame or receiver) per 27 CFR 478.92. 

The commenters stated that, once 

Ruling 2010–10 is superseded, 

gunsmiths would have to apply for a 

Type 07 manufacturer’s license if they 

want to continue performing services for 

manufacturers. One custom gunsmith of 

1911s provided an example of how the 

process of marking frames would be 

overly complex, if not impossible, to 

comply with if Ruling 2010–10 were to 

be superseded. First, the frame (e.g., a 

1911 frame) would have the original 

manufacturer’s marking; then, as the 

builder of the custom pistol, the 

commenter would place his company’s 

markings on the frame or receiver; then 

the markings of the Type 07 licensee 

that provides the checkering would be 

applied; and finally the markings of the 

Type 07 licensee that provides the 

specialized finish would be applied. 

These commenters asked that ATF 

reconsider superseding Ruling 2010–10 

or provide an exemption to allow 

custom gunsmiths and firearms 

manufacturers to use each other’s 

services in the manufacturing process 

without a requirement to mark, 

provided that the frame or receiver, as 

machined, is marked and compliant 

before the outside service is provided. 

Similarly, one manufacturer said the 

proposed definition of gunsmiths is 

underinclusive because it would allow 

gunsmiths to perform their services ‘‘on 

existing firearms not for sale or 

distribution by a licensee.’’ The 

manufacturer stated that the proposed 

change would preclude some Type 01 

licensed gunsmiths from continuing to 

perform manufacturing activities on the 

manufacturer’s behalf because those 

firearms will ultimately be intended for 

sale and distribution by the 

manufacturer. The manufacturer stated 

that this will impact several production 

lines at all of its primary manufacturing 

facilities. Another commenter stated 

that the proposed change to ‘‘gunsmith’’ 

implies that a person who is not a 

gunsmith would be prohibited from 

engraving a serial number onto the 

firearm. He stated that, if a person 

makes a PMF, that person should be 

able to serialize it. 

Department Response 

The Department agrees that the new 

definition of ‘‘gunsmith’’ will result in 

the re-licensing of many gunsmiths as 

manufacturers when they are involved 

in the production of firearms for sale or 

distribution by licensees. This is 

because persons engaged in the business 

of manufacturing firearms (i.e., frames 

or receivers or complete weapons) for 

the purpose of sale or distribution by 

completing, assembling, applying 

coatings, or otherwise making them 

suitable for use, are required to be 

licensed as manufacturers. See 18 U.S.C. 

921(a)(10), (a)(21)(A), 923(a). This is 

made clear in the revised definition of 

‘‘gunsmith’’ in the final rule. 

Nevertheless, in light of commenters’ 

concern regarding the differences 

between gunsmithing and 

manufacturing, the final rule also makes 

clear that licensed dealer-gunsmiths are 

not required to be licensed as 

manufacturers if they perform 

gunsmithing services only on existing 

firearms for their customers or for 

another licensee’s customers because 

the work is not being performed to 

create firearms for sale or distribution. 

The firearm upon which the 

gunsmithing service was performed is 

merely being returned to the individual 

from whom it was received.129 These 

services may include customizing a 

customer’s complete weapon by 

changing its appearance through 

painting, camouflaging, or engraving; 

applying protective coatings; or by 

replacing the original barrel, stock, or 

trigger mechanism with drop-in 

replacement parts. Licensed dealergunsmiths may also purchase complete 

weapons, make repairs (e.g., by 

replacing worn or broken parts), and 

resell them without being licensed as 

manufacturers. Likewise, under the final 

rule, licensed dealer-gunsmiths may 

make such repairs for other licensees 

who plan to resell them without being 

licensed as a manufacturer. They may 

also place marks of identification on 

PMFs they may purchase and sell, or 

under the direct supervision of another 

licensee in accordance with this rule. 

These activities are distinguished 

from persons who engage in the 

business of completing or assembling 

parts or parts kits; applying coatings; or 

otherwise producing new or 

remanufactured firearms (frames or 

receivers or complete weapons) for sale 

or distribution. Such persons must be 

licensed as manufacturers. See, e.g., 

Broughman v. Carver, 624 F.3d 670, 

676–77 (4th Cir. 2010), cert. denied, 563 

U.S. 1033 (2011) (licensed gunsmith 

who built and sold ‘‘custom’’ bolt action 

rifles by purchasing actions (receivers 

with internal parts) and barrels, fitting 

the barrels to the actions, bluing the 

actions, and making and attaching 

wooden stocks, was required to be 

licensed as a manufacturer). 

The Department also agrees that 

superseding ATF Ruling 2010–10 by 

this rule could be burdensome to 

licensed gunsmiths required to be 

licensed as manufacturers because they 

would now be required to place their 

own identifying marking on firearms 

already marked by a licensed 

manufacturer or importer. For this 

reason, this rule as finalized allows 

licensed manufacturers, including 

persons formerly licensed as dealergunsmiths, to adopt the serial number 

and other identifying markings 

previously placed on a firearm by 

another licensed manufacturer without 

a variance, provided that the firearm has 

not been sold, shipped, or otherwise 

disposed of to a person other than a 

licensee. This change will also reduce 

the potential for confusion by law 

enforcement when tracing a firearm 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24703 

involved in a crime if multiple markings 

were to be found on those firearms. 

Under these circumstances, there is a 

reduced concern that a trace could not 

be successfully completed because the 

required records maintained by those 

licensees would reveal a continuous 

acquisition and disposition of that 

firearm. 

However, once a firearm is sold, 

shipped, or otherwise disposed of to a 

person other than a licensee, the trace 

can be completed only to the first retail 

purchaser. After that point, it is difficult 

to trace the firearm to another licensed 

manufacturer that may have purchased 

it for remanufacture and resale or 

redistribution without the purchaser’s 

own identifying markings. For this 

reason, the final rule distinguishes 

between licensee adoption of markings 

on new firearms from those that were 

already introduced into commerce to 

nonlicensees, such as those that are 

being remanufactured or imported. 

Additionally, the final rule also allows 

licensed gunsmiths and licensed 

manufacturers that conduct 

gunsmithing activities to adopt the 

existing markings on firearms when 

they engage in gunsmithing activities on 

firearms that are not for sale or 

distribution. These changes will thereby 

supersede ATF Rulings 2009–5 and 

2010–10. Further, the final rule 

expressly clarifies that licensed 

manufacturers and importers, which are 

permitted to act as licensed dealers 

without obtaining a separate dealer’s 

license (see 27 CFR 478.41(b)), can 

perform adjustments or repairs on 

firearms for their customers without 

recording an acquisition, provided the 

firearm is returned to the person from 

whom it was received on the same day. 

Finally, with regard to PMFs, the 

Department agrees that licensed dealergunsmiths and other licensees that 

accept PMFs into inventory should be 

allowed to adopt a unique identification 

number placed by a nonlicensee if that 

identifying number otherwise meets the 

marking requirements. This allowance 

is reflected in the final rule. However, 

those licensees would still be required 

to place their abbreviated license 

number as a prefix (followed by a 

hyphen) to the existing serial number so 

that the firearm can be traced to them. 

Overall, the Department believes these 

provisions of the rule as finalized will 

mitigate the marking burden on 

licensees and make it easier for them to 

purchase and sell PMFs while 

maintaining traceability for law 

enforcement. 

4. Concerns With Marking Requirements 

for Firearms 

a. Information Required To Be Marked 

on Firearms 

Comments Received 

Numerous commenters, including 

retailers and manufacturers, objected to 

the new marking requirements on 

multiple frames or receivers or on 

PMFs, arguing that the requirements 

would be too burdensome and 

confusing. Several manufacturers raised 

questions about what would be required 

of them. Some expressed confusion as to 

whether manufacturers and importers 

are to mark multiple parts of a single 

weapon with different serial numbers or 

if they are to mark separate components 

of a single weapon with the same serial 

number. Others asked if manufacturers 

of a present split or modular firearm 

configuration would continue to mark 

only the part they presently mark or if 

the NPRM would require them to mark 

more than one part until they receive a 

classification. 

Another manufacturer observed that, 

if a single firearm will have two or more 

frames or receivers, the manufacturer 

will produce and serialize them as 

separate parts, at different times, in 

different production lines. Each separate 

part will be a separate ‘‘firearm,’’ and 

the serial number on each will duplicate 

the serial number on other(s) until they 

are put together. These separate 

‘‘firearms’’ may sit in different bins until 

assembled, all the while continuing to 

have duplicate serial numbers, thus 

violating the regulation against 

duplicate serial numbers. See 27 CFR 

479.102(a)(1). There is also a risk, the 

manufacturer stated, that frames or 

receivers with different serial numbers 

could be mixed up during production or 

distribution, or even by the end user, 

resulting in firearms with two different 

serial numbers. At least one 

manufacturer did not understand why 

the rule would require manufacturers to 

mark the caliber and model on more 

than one frame or receiver if, in the 

alternative, this marking could 

otherwise appear solely on the barrel or 

pistol slide (if applicable). 

Another manufacturer stated that, 

although it is technically possible to 

serialize more than one part, for a small 

manufacturer to coordinate all of these 

components into batches for the various 

models and configurations with 

machine-engraved numbers would be 

challenging and very expensive. The 

manufacturer pointed out that, if all 

items are marked in advance and any 

one part fails a quality control process, 

it would lose the value of all three 

components and the manufacturer’s 

scrap costs would increase significantly. 

Commenters asserted that, in the case 

of modular-type weapons, such as 

existing AR–15s, owners would be 

required to place serial numbers on 

parts that did not previously require 

them or would be prevented from 

swapping out upper and lower 

receivers, which is commonly done by 

firearms owners. Similarly, another 

commenter said that, without limiting 

the fire control components, videos 

show that 16 items in a typical Glock 

semiautomatic pistol would each be 

considered a frame or receiver and thus 

each part would need to be serialized 

and tracked. Others asked if there would 

be a controlling serial number for the 

firearm in the event that serialized parts 

are exchanged and a firearm has more 

than one serial number. 

Additional commenters worried that 

the new definitions and marking 

requirements make transfer and 

background checks of firearms very 

confusing and potentially costly. 

Commenters argued that, even if a 

consumer thinks that he or she is 

purchasing only one firearm, the reality 

is that a firearm with numerous serial 

numbers would need separate 

background checks, which in some 

States would mean additional fees. 

Further, others argued that this would 

create a mess for recordkeeping and 

trigger multiple sales reporting. They 

stated that, if a firearm has multiple 

frames or receivers, each part with a 

different serial number is a ‘‘firearm’’ 

unto itself. They questioned whether an 

FFL selling this type of firearm(s) would 

list several serial numbers on the ATF 

Form 4473 or whether the consumer 

would have to fill out more than one 

ATF Form 4473. In these types of 

scenarios, they questioned whether an 

FFL would be required to file a multiple 

handgun sales report or for—those 

retailers in the States of Texas, New 

Mexico, Arizona, and California—fulfill 

the multiple rifle reporting requirement. 

Others argued that the NPRM did not 

address States where residents are 

limited to purchasing one handgun a 

month. They argued that, if a firearm 

has multiple frames or receivers, each of 

which is a firearm by law, then 

individuals could be prevented from 

buying a handgun in States with these 

limitations. 

Another issue that several 

commenters raised is that they would 

not be able to fit all the new information 

on certain parts that will now be 

considered frames or receivers. For 

example, they stated that the NPRM 

requires serial number of an internal or 

drop in chassis frame or receiver (e.g., 


jspears on DSK121TN23PROD with RULES2
24704 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

P320–type) to be unobstructed to the 

naked eye. The commenters said it is 

unclear how a manufacturer can safely 

place a lengthy abbreviated FFL number 

and the other requirements in the 

‘‘window’’ of the polymer frame pistol 

so that the required information is 

visible. They stated that the inability to 

fit the new marking requirements is 

even more acute on smaller pistols or on 

certain curio and relic bolt action 

firearms. 

Another manufacturer said that it 

would need to design and acquire 

dozens of new molds to fulfill the new 

requirements for marking and that a 

typical mold costs approximately 

$100,000. The manufacturer stated it 

also would need to essentially modify 

all molds for polymer grip frames with 

the expanded marking requirements 

(such as by measuring from the flat 

surface of the metal and not the peaks 

or ridges, and by ensuring the markings 

are not susceptible to obliteration). This 

manufacturer also inquired how FFLs 

are supposed to measure the depth of 

markings after certain coatings are 

applied. Assuming the grip frames and 

trigger assembles will be frames or 

receivers under the NPRM, the 

manufacturer stated that it would have 

to modify each grip frame or trigger 

assembly to include a metallic plate 

suitable for marking a serial number, 

which would increase the costs for itself 

and suppliers of these parts, and also 

require it to obtain a marking variance. 

With regard to the content of the 

markings, one commenter wrote that the 

preamble of the NPRM contemplates 

that the new marking requirement could 

be satisfied by solely marking the 

licensee’s name and RDS code plus a 

unique number (‘‘RDS+’’) and that the 

RDS+ would satisfy the unique ‘‘serial 

number’’ requirement. The commenter 

expressed confusion because the 

preamble indicates that the RDS+ suffix 

could include alphabetic characters, but 

the rule, despite defining ‘‘legibly,’’ 

seems to limit the suffix to numerals 

only, as the rule uses the term 

‘‘number’’ in several sections, such as 

§ 479.102(a)(1). The commenter 

indicated that the contradictory 

information between the explanation in 

the preamble and the regulatory text 

itself is problematic because almost all 

manufacturers use alphabetic characters 

in their serial numbers. Other 

commenters pointed out that a modular 

lower can have its caliber changed and 

that, absent an upper, there is no way 

a manufacturer can mark a weapon with 

its caliber. They stated that the caliber 

should not be required on modular type 

weapons. They also asserted that 

requiring the caliber to be marked 

would be futile because owners can 

simply change the caliber by replacing 

the upper. 

Department Response 

As stated previously, the Department 

agrees with numerous commenters that 

there should be only one ‘‘frame or 

receiver’’ in a given weapon or device. 

The Department has, therefore, added a 

new definition of ‘‘frame or receiver’’ in 

27 CFR 478.11 and 479.11, as described 

herein, that focuses on one housing or 

structural component of a particular fire 

control or internal sound reduction 

component for a given weapon or 

device. Because of these revisions, there 

would almost always be one unique 

serial number marked on any such 

weapon or device, even if the 

components of a split or modular 

weapon were removed and reassembled 

using different components. To ensure 

that industry members and others can 

rely on ATF’s prior classifications, 

almost all classifications and variants 

thereof have been grandfathered into the 

definition of ‘‘frame or receiver.’’ Frame 

or receiver designs that have been 

grandfathered under the definitions may 

continue to be marked in the same 

manner as before the effective date of 

the final rule. This change should 

address concerns raised by 

manufacturers that their costs would 

increase in order to mark their existing 

frames or receivers with the new 

marking requirements or to record 

multiple markings in connection with 

complete weapons or complete muffler 

or silencer devices, and by retailers that 

would have been required to run more 

background checks for more items 

classified as the ‘‘frame or receiver’’ 

under the rule as proposed. 

In response to comments on the 

content of the markings, the Department 

agrees with the comment that there 

could be confusion in the regulatory text 

as to the ‘‘number’’ that must be marked 

after the RDS Key, described in the rule 

as the licensee’s abbreviated Federal 

firearms license number. For this 

reason, the regulatory text has been 

amended to change the word ‘‘number’’ 

to ‘‘unique identification number’’ in 

§§ 478.92(a) and 479.102(a), where 

appropriate, to ensure that this 

particular marking is part of the ‘‘serial 

number’’ in that scenario. The unique 

identification number may include both 

alphabetic and numeric characters as 

stated in the definition of ‘‘legibly.’’ 

The Department disagrees with the 

comment saying that caliber or gauge 

should not be a required marking for 

split or modular weapons. Information 

concerning the caliber or gauge of a 

weapon is useful to distinguish between 

firearms during a trace or when 

matching projectiles to a particular 

weapon found at a crime scene. To 

mitigate the problem raised by 

commenters that a modular weapon’s 

caliber can change, the final rule makes 

clear the model designation and caliber 

or gauge may be omitted if that 

information is unknown at the time a 

frame or receiver is sold, shipped, or 

otherwise disposed of separately from 

the complete weapon or complete 

muffler or silencer device. 

b. Markings on ‘‘Split or Modular 

Frames or Receivers’’ 

Comments Received 

Some manufacturers asked how they 

would handle warranty repairs of a 

modular or split receiver firearm under 

the NPRM if one of the marked parts 

must be replaced to make the firearm 

safe to use. They stated that a 

manufacturer would not be able to 

provide a replacement part because it 

cannot reuse the serial number or return 

the firearm with unmarked 

component(s) that are now considered 

to be the frame or receiver. If they did, 

the replacement part would be marked 

with a different serial number, placing 

the manufacturer in violation of section 

923(i) of the GCA. They also asked if 

disassembly (e.g., routine cleaning or 

replacement or repair of a part ATF 

would classify as frame or receiver) 

would constitute removal of the 

manufacturer or importer serial number 

in violation of 18 U.S.C. 922(k). 

Department Response 

Unlike the proposed rule, this final 

rule does not require multiple parts of 

a split frame or receiver to be marked 

(i.e., only the upper receiver of a split 

receiver rifle need be marked, unless the 

lower is the grandfathered part). Thus, 

non-serialized parts of a split frame or 

receiver may be replaced without 

violating section 923(i). However, the 

final rule explains that similar modular 

subparts of a ‘‘multi-piece frame or 

receiver’’ (e.g., two similar left and right 

halves of a frame or receiver) must be 

marked with the same serial number 

and associated licensee information. If 

one of those parts is removed and 

replaced with an unserialized part, then 

the possessor would violate section 

922(k) for possessing a firearm with a 

removed serial number. However, the 

final rule sets forth a process by which 

a marked modular subpart of a non-NFA 

multi-piece frame or receiver may be 

removed and replaced without violating 

section 922(k). The replacement 

modular subpart must be marked by its 

manufacturer with the same original 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24705 

130Cf. United States v. Mixon, 166 F.3d 1216 

1998 WL 739897, at *3 (6th Cir. 1998) (table) (‘‘The 

fact that the entire serial number or other 

indications of the serial number on the weapon 

were not obliterated fails to negate the fact that a 

portion of the serial number had been obliterated.’’); 

United States v. Frett, 492 F. Supp. 3d 446, 4552 

(D.V.I. 2020) (‘‘[T]he Court holds that a firearm 

bearing multiple serial numbers, only one of which 

is removed, ‘has had the importer’s or 

manufacturer’s serial number removed, obliterated, 

or altered’ within the meaning of Section 922(k).’’). 

serial number and associated licensee 

information, and the original part must 

be destroyed prior to such placement. 

More specifically, under 18 U.S.C. 

923(i) and 26 U.S.C. 5842(a), ATF has 

the authority to prescribe by regulations 

the manner in which licensed 

manufacturers and importers (and 

makers of NFA firearms) must identify 

a serial number on the frame or receiver 

of a weapon. Because multi-piece 

frames or receivers may be partitioned 

into similar modular subparts that could 

be produced and sold separately, each 

subpart must be identified with the 

same serial number and associated 

licensee information so that the frame or 

receiver, once complete (assembled or 

unassembled), can be traced to its 

manufacturer. The serial number 

identified on each subpart must be the 

same number so that the complete frame 

or receiver does not have a serial 

number duplicated on any other firearm 

produced by the manufacturer. Once the 

modular subparts are aggregated as a 

complete multi-piece frame or receiver, 

a modular subpart identified with the 

serial number cannot be removed and 

replaced unless the destruction 

procedure set forth in this rule is 

followed. See 18 U.S.C. 922(k); 27 CFR 

478.34 (prohibiting possession or 

receipt of a firearm that has had the 

importer’s or manufacturer’s serial 

number removed); see also 26 U.S.C. 

5861(g), (h) (prohibiting removal of the 

serial number or possession of an NFA 

firearm from which the serial number 

has been removed).130

c. Size and Depth of Markings 

Comments Received 

Another issue raised by commenters 

is the feasibility of doing an engraving 

to meet the new size specifications. One 

organization stated that, currently, the 

print size and depth limitations pertain 

only to serial numbers and not the 

additional information (i.e., 

manufacturer’s or importer’s city or 

State). The proposed change to require 

that the serial number and additional 

information be engraved to a minimum 

depth of .003 inches and in a print size 

no smaller than 1/16 inch, per the 

proposed § 478.92(a)(i)(iv), would 

assertedly make it difficult or 

impossible to comply. 

Department Response 

The Department agrees with this 

comment, and as stated in the preamble 

of the proposed rule, this rule would not 

change the existing requirements for 

size and depth of markings. 

Consequently, the text of this paragraph 

in the final rule is amended to clarify 

that only the serial number and any 

associated license number must be in a 

print size no smaller than 1⁄16 inch. 

d. Period of Time To Identify Firearms 

Comments Received 

Some commenters were concerned 

that the seven-day time limit in the 

proposed rule for qualified 

manufacturers to identify NFA firearms 

contradicts existing law because ATF 

Form 2, Notice of Firearms 

Manufactured or Imported, must be 

filed by the close of the next business 

day after manufacture, pursuant to 27 

CFR 478.103. Accord United States v. 

Walsh, 791 F.2d 811, 818 (10th Cir. 

1986) (‘‘The registration procedure for 

manufactured firearms contained in the 

Treasury regulation does not provide 

additional time within which to place a 

serial number on a firearm.’’). One of 

these commenters was also concerned 

that the term ‘‘active manufacturing 

process’’ for purposes of applying the 

seven-day time limit was vague because 

a suppressor may be functional in some 

capacity even if the manufacturer is 

waiting for additional baffles to replace 

damaged or incorrectly manufactured 

parts that were previously produced. 

Department Response 

The Department agrees with these 

commenters that the proposed sevenday time limit to mark NFA firearms is 

inconsistent with the ‘‘close of next 

business day’’ filing requirement for 

ATF Form 2, which must include the 

serial number of the firearms 

manufactured. For this reason, the final 

rule makes clear that weapons and parts 

defined as ‘‘firearms’’ only under the 

GCA, but not the NFA, must be 

identified not later than the seventh day 

following the date the entire 

manufacturing process has ended for the 

weapon (or frame or receiver, if 

disposed of separately), or prior to 

disposition, whichever is sooner. 

Weapons and parts defined as 

‘‘firearms’’ produced under the NFA 

must be marked by close of the next 

business day. In this way, the marking 

requirements under the GCA or NFA 

will be consistent with their applicable 

recordkeeping requirements, while 

providing reasonable grace periods in 

which to identify firearms after the 

entire manufacturing process has ended. 

The Department also believes that the 

phrases ‘‘actively awaiting materials’’ 

and ‘‘completion of the active 

manufacturing process’’ should be made 

clearer in the final rule. For this reason, 

the final rule no longer uses the term 

‘‘actively awaiting materials’’ and 

instead establishes a presumption that 

firearms awaiting materials, parts, or 

equipment repair to be completed are, 

absent reliable evidence to the contrary, 

in the manufacturing process. The final 

rule also substitutes the phrase 

‘‘completion of the active manufacturing 

process’’ for ‘‘the entire manufacturing 

process has ended’’ in determining the 

applicable time limit to identify 

firearms. 

e. Marking ‘‘Privately Made Firearms’’ 

Comments Received 

Numerous commenters objected to the 

requirement that PMFs be serialized. 

Many believed that the proposed rule 

would require makers of PMFs that are 

non-NFA weapons to serialize their 

firearms and emphasized that it should 

be optional, not required, for a person 

to serialize the person’s own guns. They 

asserted that holding private individuals 

to the same standards as commercial or 

corporate FFLs is unreasonably 

burdensome. Others pointed out that 

most PMFs are made from polymer or 

plastic and that there is no way to insert 

a piece of metal, which would be 

required per the proposed regulations, 

unless they go to a dealer or gunsmith 

and pay for extensive modifications. 

Commenters also said that forcing 

dealers to mark PMFs with their license 

information simply because a PMF 

owner took a firearm in for repair or 

upgrade is an added cost because the 

dealers will have to obtain additional 

equipment that is not needed for their 

daily operations and could be subject to 

liability if their FFL information is 

attached to a PMF. Commenters also 

asserted that PMF owners would not 

want their PMFs marked and that the 

rule would therefore prevent them from 

getting their PMFs repaired by FFLs or 

gunsmiths. 

With respect to marking PMFs, 

commenters claimed that it would not 

be reasonable to expect an FFL retailer 

to know how to safely serialize a custom 

PMF because the safety of the firearm 

could be compromised if markings are 

placed in critical areas. Moreover, 

commenters said that many FFLs will 

not have the capability to mark firearms 

with serial numbers and thus would not 

be able to acquire and ship nonserialized PMFs to other dealers for 


jspears on DSK121TN23PROD with RULES2
24706 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

131The European Union (EU), for example, has 

issued a directive specifying how member countries 

are to mark polymer frames or receivers: ‘‘For 

frames or receivers made from a non-metallic 

material of a kind specified by the Member State, 

the marking is applied to a metal plate that is 

permanently embedded in the material of the frame 

or receiver in such a way that: (a) The plate cannot 

be easily or readily removed; and (b) removing the 

plate would destroy a portion of the frame or 

receiver. Member States may also permit the use of 

other techniques for marking such frames or 

receivers, provided that those techniques ensure an 

equivalent level of clarity and permanence for the 

marking.’’ Commission Implementing Directive 

(EU) 2019/68 of 16 January 2019 Establishing 

Technical Specifications for the Marking of 

Firearms and Their Essential Components Under 

Council Directive 91/477/EEC on Control of the 

Acquisition and Possession of Weapons, annex. 

132See footnote 69, supra. 

customers. Manufacturer FFLs and trade 

organizations similarly stated that PMFs 

are not subject to the same quality 

control as commercial arms and that 

FFLs would face more liability if they 

ran into problems adding a serial 

number to a customized PMF. 

Other commenters discussed the 

burden associated with requiring PMFs 

to be marked any time one is received 

into inventory even if it is received for 

purposes limited to activities such as 

bore sighting or onsite adjustments at 

sporting events. The commenters stated 

that an FFL would not be able to 

perform a function test or other quick 

gunsmithing without first recording it in 

the A&D records and adding a serial 

number. Another commenter asked if an 

FFL would have to re-serialize a PMF if 

the PMF had already been marked with 

the private builder’s own serial number. 

The commenter asserted it would be 

better for ATF to provide a best 

practices recommendation as to how 

FFLs may mark a PMF rather than 

making it a mandatory regulation. In 

addition, one commenter believed that 

one implication of the rule is that 

makers of PMFs would not be able to 

serialize their own PMFs because only 

FFLs would be able to serialize them. 

Commenters also stated the marking 

requirement seems to require the use of 

laser, engraving, or CNC mill machines 

with engraving capabilities, given the 

mandatory depth and size requirements, 

which comments said could not be 

satisfied with simple and cheap 

engraving tools. Also, specifically with 

respect to PMFs, one FFL/SOT holder 

stated that metal plates on common 

polymer PMFs are often not large 

enough to engrave the proposed 10-plus 

character number to ATF size 

requirements. The suggestion from ATF 

in the NPRM that FFLs embed metal 

plates into PMFs, according to the 

commenter, does not comprehend the 

variety of materials—including epoxies, 

resins, ceramics, thermoset plastics, and 

well-known materials such as Bakelite— 

that do not allow for doing so. 

A few commenters asserted that seven 

days is not sufficient time for FFLs to 

mark PMFs. Some argued there is no 

realistic way to mark a PMF in seven 

days because extra time would be 

needed to disassemble a completed PMF 

to mark it properly; or, if the FFL had 

no resources to engrave a serial number, 

then the FFL would have to send it out 

for marking, and it would be unlikely 

that the firearm could be marked within 

that time period if businesses that can 

do the marking have a backlog of work. 

Similarly, commenters argued that 

requiring FFLs to mark, or supervise the 

marking of, serial numbers of PMFs in 

their inventory within a seven-day 

period would severely interrupt FFLs’ 

ability to conduct such business and 

they would likely turn away unmarked 

PMFs to avoid these burdensome 

regulatory requirements. Others argued 

that the period of time should be 

extended to 21 days to account for 

delays, which could be caused by 

weather, fuel shortages, or shipper 

incompetence when shipping PMFs to 

another licensee, such as a gunsmith, for 

marking. 

Department Response 

As an initial matter, the Department 

notes that nothing in this rule requires 

private individuals to mark their 

personally made (non-NFA) firearms or 

to present them to licensees for marking. 

Nothing in this rule requires licensees to 

accept PMFs into inventory, mark PMFs 

with the name of the private maker, or 

record the maker’s name as the 

‘‘manufacturer’’ of the firearm. This rule 

requires only that PMFs voluntarily 

taken into inventory by FFLs be marked 

with a serial number prefixed with the 

licensee’s abbreviated license number 

and for the FFL to record the acquisition 

information. This requirement allows 

the PMF to be traced directly to the 

licensee, not the private maker, if later 

used in a crime. 

This rule explains in detail how 

accepting PMFs into inventory without 

serial numbers undermines the entire 

purpose of maintaining transaction 

records and other required records. For 

example, if multiple unmarked PMFs of 

the same ‘‘type’’ are accepted into 

inventory—each recorded only as a 

‘‘pistol’’—they would be 

indistinguishable from each other for 

tracing and other law enforcement 

purposes. Even if a PMF could be traced 

to a particular firearms licensee, there 

would be no information marked on that 

weapon that could be matched to a 

specific recordkeeping entry in either 

the acquisition or disposition book, ATF 

Form 4473, theft/loss report, or multiple 

sales report. For these reasons, PMFs 

must be marked with a traceable serial 

number like other firearms, but they do 

not need to be marked with the name of 

the private maker. As the proposed rule 

explained, PMFs would typically be 

marked by permanently embedding a 

metal plate into the polymer. 86 FR at 

27732. Many, if not most, PMF parts kits 

already have a metal plate embedded 

into the partially complete frame or 

receiver for serialization purposes and 

to assist purchasers in complying with 

some State, local, or international 

laws.131 If a licensee does not have the 

capability to mark, the licensee can 

arrange for private individuals to have 

the PMFs marked by another person 

before accepting them, or, after 

acceptance, arrange for PMFs to be 

marked under the licensee’s direct 

supervision with the licensee’s serial 

number. 

The Department also disagrees that 

metal serial number plates cannot be 

embedded or overprinted 132 into 

polymer materials, or that the serial 

number plates currently embedded 

within polymer frames or receiver are 

not or cannot be made large enough to 

be marked with at least 10 characters at 

the minimum 1⁄16-inch print size. The 

Department further believes that, as 

technology develops, it will become 

easier and cheaper for licensees to 

embed metal plates into polymer 

materials. Although, upon issuance of 

this rule, it may be difficult for licensees 

to mark some PMFs that they might 

have taken into inventory (i.e., those 

without previously embedded serial 

number plates), the Department believes 

the final rule provides a sufficiently 

long grace period for them to mark or 

arrange for them to be marked by 

another licensee. Specifically, licensees 

will have from the date the final rule is 

published until 60 days after the 

effective date to properly mark and 

identify PMFs as required by the 

regulations. 

Nonetheless, the Department agrees 

with some commenters that licensees, 

including dealer-gunsmiths, should be 

allowed to adopt a unique identification 

number previously placed on a PMF by 

a private maker that is not duplicated on 

another firearm of the licensee and 

otherwise meets the identification 

requirements of this section provided 

that, within the period and in the 

manner herein prescribed, the licensee 

legibly and conspicuously places, or 

causes to be placed, on the frame or 

receiver thereof the licensee’s own 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24707 

133See ATF Rul.77–1 (holding that a firearm need 

not be entered into the bound A&D record if the 

firearm is brought in for adjustment or repair and 

the customer waits while it is being adjusted or 

repaired, ‘‘or if the gunsmith returns the firearm to 

the customer during the same business day it is 

brought in,’’ but noting that, if the ’’ the firearm is 

retained from one business day to another or longer, 

it must be recorded in the bound acquisition and 

disposition record’’); ATF, Does a gunsmith need to 

enter every firearm received for adjustment or 

repair into an acquisition and disposition (A&D) 

record? (July 13, 2020), available at https://

www.atf.gov/firearms/qa/does-gunsmith-needenter-every-firearm-received-adjustment-or-repairacquisition-and. This final rule clarifies ATF Rul. 

77–1 by explaining that licensed manufacturers and 

importers, who may engage in the business as a 

licensed dealer without obtaining a separate license 

(see 27 CFR 478.41(b)), may also perform same-day 

adjustment or repair without an acquisition record 

entry. 

abbreviated Federal firearms license 

number, which is the first three and last 

five digits, followed by a hyphen, before 

the existing unique identification 

number, e.g., ‘‘12345678-[unique 

identification number].’’ Again, these 

markings will allow the PMF to be 

traced to the licensee if later recovered 

at a crime scene. 

Finally, the Department agrees with 

the comment that dealer-gunsmiths, as 

well as licensed manufacturers and 

importers, should be allowed to perform 

a function test and quick repairs on a 

PMF. For this reason, the final rule 

clarifies that licensed dealer-gunsmiths, 

manufacturers, and importers may 

conduct same-day adjustments or 

repairs on PMFs without having to place 

identifying markings or record the 

receipt as an acquisition or subsequent 

disposition upon return. This is not a 

significant change from the proposed 

rule because it provides consistency for 

same-day adjustment or repair by 

treating PMFs the same as commercially 

produced firearms in that they must be 

recorded in inventory only if repaired 

overnight. ATF has long maintained 

that, if a firearm is brought in for 

adjustment or repair where the person 

waits while it is being adjusted or 

repaired, or if the gunsmith is able to 

return the firearm to the person during 

the same business day, it is not 

necessary to list the firearm in the 

gunsmith’s A&D records as an 

‘‘acquisition.’’ 133 If the gunsmith has 

possession of the firearm from one day 

to another or longer, the firearm 

received by the gunsmith must be 

recorded as an ‘‘acquisition’’ and then 

as a ‘‘disposition’’ in the gunsmith’s 

A&D records upon return to the same 

customer. However, the final rule makes 

clear that a PMF must be recorded as an 

acquisition whenever it is marked for 

identification, including same-day or 

on-the-spot. The only exception is when 

the firearm is marked by another 

licensee under the licensee’s direct 

supervision with the licensee’s serial 

number because the firearm has already 

been recorded as an acquisition. 

f. Adoption of Identifying Markings 

Comments Received 

Some commenters stated that the 

explanation in the NPRM’s preamble on 

the ‘‘Marking of Privately Made 

Firearms’’ indicated that FFLs must 

always mark PMFs upon acquisition 

even if the private maker has already 

added a serial number. Commenters 

stated that markings PMFs with a 

manufacturer’s name, location, and a 

unique serial number is equivalent to 

the markings of a commercial firearm 

and therefore the regulation should 

account for PMFs already so marked. 

Similarly, they raised questions about 

the effect of the proposed rule for NFA 

firearms that have been approved 

through an ATF Form 1 and already 

recorded in the NFRTR. They asked if 

the original markings, as done by the 

maker of the firearm and recorded in the 

NFRTR, can be adopted by the FFL that 

acquires the PMF. Others asked whether 

the new marking requirements would 

render owners of pre-1986 

machineguns, short-barreled rifles, 

short-barreled shotguns, and any other 

weapons under the NFA noncompliant 

with the NFA, as many of these firearms 

have only the lower receiver serialized 

and not other parts that could be 

deemed a frame or receiver under the 

NPRM. 

Department Response 

The Department agrees with 

commenters who said that PMFs that 

were manufactured or ‘‘made’’ privately 

should be treated similarly to 

commercial firearms when they are 

received by FFLs. The Department 

therefore agrees that FFLs should be 

allowed to adopt a unique identification 

number on a PMF if it otherwise meets 

the marking requirements. This final 

rule allows such adoption as an 

exception. However, unlike 

commercially produced firearms, 

private makers are not required to 

maintain records of production and 

transfer, and, under the GCA, firearms 

involved in crime are traced to 

licensees, not private makers. For this 

reason, licensees wishing to adopt the 

unique identification number marked by 

a private maker on a PMF would still 

need to add their abbreviated license 

number as a prefix to the unique 

identification number so adopted. In 

that way, the firearm can be traced to a 

licensee. 

With regard to privately made NFA 

firearms, the rule as proposed and 

finalized does not define the term 

‘‘privately made firearm’’ to include 

NFA firearms that have been identified 

and registered in the NFRTR pursuant to 

chapter 53, title 26, United States Code, 

or any firearm manufactured or made 

before October 22, 1968 (unless 

remanufactured after that date) that 

were not required to be marked. 

Furthermore, as stated previously, this 

rule requires marking only of a single 

component and grandfathers all prior 

ATF classifications except for partially 

completed, disassembled, or 

nonfunctional frames or receivers, 

including parts kits, that ATF 

determined were not firearm ‘‘frames or 

receivers’’ as defined prior to this rule. 

g. Marking of ‘‘Firearm Muffler or 

Silencer Frame or Receiver’’ 

Comments Received 

Numerous commenters asserted that 

silencers should not be regulated at all 

because they are used solely to protect 

a shooter’s hearing by reducing the 

sound levels of firearms and do not 

make a firearm any more dangerous or 

affect the function of a firearm other 

than managing recoil. Therefore, they 

argued, there should be no requirement 

to mark or serialize these devices. They 

stated that almost no crimes outside of 

Hollywood movies are committed while 

using silencers and that unnecessary 

paperwork, taxes, wait times, and 

regulations have deprived firearm 

owners from obtaining a simple device 

that could help them avoid hearing loss. 

Others pointed out that there are a 

number of silencers without an outer 

tube, such as the Q erector, and there is 

no clear way to fit such a device within 

the proposed rule. They recommended 

the rule be more flexible by allowing for 

serialization requirements to be 

determined by the model of the silencer. 

The American Suppressor Association 

(‘‘ASA’’) referenced ATF’s current 

guidance to industry that ‘‘[t]he 

replacement of the outer tube is so 

significant an event that it amounts to 

the ‘making’ of a new silencer.’’ 

Accordingly, ASA pointed out that, 

under ATF’s current guidance, the new 

silencer needs to be marked, registered, 

and transferred in accordance with the 

NFA and GCA. ASA asserted that this 

current guidance is unsupported by 

statute and should be addressed in the 

NPRM. ASA opined that remaking the 

outer tube for a silencer does not 

constitute the making of a new silencer 

under the NFA when such remaking is: 

(1) Completed by the original 

manufacturer of the silencer in question; 


jspears on DSK121TN23PROD with RULES2
24708 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

and (2) the remade outer tube is marked 

with the same serial number as the 

replaced outer tube. ASA asked that 

ATF allow for the replacement of a 

silencer’s outer tube in these instances 

and opined that the NPRM’s new 

definition of ‘‘frame or receiver’’ for 

silencers is a perfect forum for ATF to 

announce and codify this 

reconsideration. 

Department Response 

The Department disagrees with 

comments that silencers should not be 

marked with serial numbers. Both the 

GCA and NFA regulate firearm mufflers 

and silencers as ‘‘firearms.’’ 18 U.S.C. 

921(a)(3)(C); 26 U.S.C. 5845(a)(7). The 

GCA and NFA require silencers, like 

other firearms, to be identified with a 

serial number, see 18 U.S.C. 923(i); 26 

U.S.C. 5842(a), and they could not be 

registered in the NFRTR without a serial 

number. This rule sets forth when and 

how silencers must be serialized. It 

makes it easier for manufacturers, 

importers, and makers to place serial 

numbers by requiring only one part of 

a complete firearm muffler or silencer 

device (i.e., the frame or receiver, as 

defined), to be marked and not the other 

silencer parts when transferred between 

qualified licensees for further 

manufacture or repair of complete 

devices. 

With respect to modular silencers like 

the Q erector, the final rule makes clear 

that, in the case of a modular firearm 

muffler or silencer device with more 

than one part that provides housing or 

a structure for the primary internal 

component designed to reduce the 

sound of a projectile (i.e., baffles, 

baffling material, or expansion 

chamber), the term ‘‘frame or receiver’’ 

means ‘‘the principal housing attached 

to the weapon that expels a projectile, 

even if an adapter or other attachments 

are required to connect the part to the 

weapon.’’ 

The Department also does not agree 

with the comment that the final rule 

should allow for the replacement of a 

silencer’s outer tube by its SOT 

manufacturer when the original tube is 

destroyed, and the replacement is 

marked with the original serial number. 

Under the NFA, 26 U.S.C. 5841(b)–(c), 

each qualified manufacturer must 

register in the NFRTR each firearm it 

manufactures and notify ATF of such 

manufacture to effect the registration. 

ATF has taken the position that the 

replacement of a serialized outer tube, 

now defined as the frame or receiver, is 

such a significant manufacturing 

activity that it results in the 

manufacture of a new silencer for which 

notification is required. See ATF, 

National Firearms Act Handbook— 

Appendix B—Frequently Asked 

Questions—Silencers at 175–76, 

available at https://www.atf.gov/files/ 

publications/download/p/atf-p-5320-8/ 

atf-p-5320-8.pdf. Additionally, unlike 

the return of an NFA firearm conveyed 

for repair, qualified manufacturers are 

required to pay transfer tax when a new 

silencer is transferred to an unlicensed 

person. See 26 U.S.C. 5811. Therefore, 

allowing manufacturers to create and 

return new NFA firearms, including 

silencers, without notification to ATF or 

payment of transfer tax would be 

contrary to law. 

h. Firearms Designed and Configured 

Before Effective Date of the Rule 

Comments Received 

Numerous commenters expressed 

concern that the grandfathering 

provision regarding marking in the 

NPRM is unclear and that they would 

not know if the new marking 

requirements would be triggered 

without more clarity from ATF. 

Commenters pointed out that the NPRM 

says licensed manufacturers and 

importers may continue to identify the 

additional firearms (other than PMFs) of 

the same ‘‘design and configuration’’ as 

they existed before the effective date. 

They stated the use of ‘‘and’’ in this 

phrase indicates that both criteria must 

be met for the grandfathering clause to 

apply and thus they were uncertain 

when changes to a particular firearm 

model remove it from the grandfathering 

protection. One manufacturer stated that 

it routinely introduces new SKUs that 

differ from existing designs and 

configurations in minor ways. Likewise, 

others asked if a change in grip panels, 

barrel length, or fixed sights versus 

adjustable or red-dot capable sights 

would result in a change in design or 

configuration. Accordingly, they 

requested that ATF give clarity to the 

terms ‘‘design’’ and ‘‘configuration’’ as 

well as ensure that the current 

definition of frame or receiver is 

preserved for grandfathered firearms 

that will continue to follow the old 

marking requirements so as to avoid 

creating a third category of firearms that 

do not fit within either the old or new 

marking requirements. They also stated 

that they will face new burdens 

regarding future firearms designs and 

configurations without knowing the 

meaning of those terms. 

One trade group that represents 

importers stated that ATF needs to 

clarify whether its grandfather provision 

for marking means that all previously 

manufactured models and 

configurations are not required to be 

marked under the new requirements. 

Specifically, the group asked if firearms 

manufactured overseas before the 

publication of the rule, but imported 

afterwards, are exempt from the new 

requirements. If they are not exempt, the 

group stated, then an exemption should 

be drafted that allows the markings to be 

engraved on the barrel or slide when the 

receiver is too small to mark 

conspicuously. The group argued that 

simply allowing for this result by 

variances is inefficient. 

Another FFL said the rule does not 

address whether a manufacturer is 

supposed to mark, or register as 

acquired, parts already in its physical 

inventory if those parts now meet the 

new definition of frame or receiver 

when those parts are used in the 

assembly of a complete firearm that is 

of a new design or configuration. The 

FFL also stated it is unclear what 

serialization information should be put 

on ‘‘newly’’ defined frame or receiver 

parts that are vendor supplied but 

already in its inventory. Alternatively, it 

said, if serialization is not required, then 

the rule should address whether a 

licensee would be required to place the 

unserialized firearms in its A&D records 

with a serial number of ‘‘No Serial 

Number’’ (‘‘NSN’’). The FFL further 

pointed to extraneous impacts of the 

proposed definition and marking 

requirements, noting that manufacturers 

use outside, non-licensed vendors to 

supply numerous firearm components, 

many of which could fall under the 

definition of frame or receiver, thus 

forcing these vendors to become 

licensees and meet the new marking and 

recording requirements. 

Department Response 

The Department agrees with 

commenters that the grandfathering of 

firearms should be clarified by ensuring 

that the current definition of frame or 

receiver is preserved for existing 

firearms and by clarifying the meaning 

of ‘‘design and configuration’’ in the 

proposed rule. In light of these 

comments, the final rule recognizes 

ATF’s prior classifications identifying a 

specific component of a given weapon 

as ‘‘the’’ frame or receiver, including 

variants thereof, as falling within the 

new definition of ‘‘frame or receiver.’’ 

Only ATF’s prior determinations that a 

partially complete, disassembled, or 

nonfunctional frame or receiver, 

including a parts kit, was not, or did not 

include, a firearm ‘‘frame or receiver’’ as 

defined prior to this rule are excluded 

from the grandfathering clause. Such 

determinations include those in which 

ATF had determined that the item or kit 

had not yet reached a stage of 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24709 

manufacture to be, or include, a ‘‘frame 

or receiver’’ under the existing 

definitions. Because this rule expressly 

regulates weapon and frame or receiver 

parts kits, and aggregations of parts with 

partially complete frames or receivers 

that are designed to, or may readily be 

converted to, expel a projectile, these 

prior ATF classifications (in which the 

entire kit may not have been presented 

to ATF at the time of classification) will 

need to be re-evaluated on a case-bycase basis. 

To address confusion concerning the 

meaning of ‘‘new design and 

configuration,’’ the final rule retains the 

marking grandfathering provision, but 

revises the text to remove ‘‘and 

configuration’’ and defines ‘‘new 

design’’ to mean ‘‘that the design of the 

existing frame or receiver has been 

functionally modified or altered, as 

distinguished from performing a 

cosmetic process that adds to or changes 

the decoration of the frame or receiver 

(e.g., painting or engraving), or by 

adding or replacing stocks, barrels, or 

accessories to the frame or receiver.’’ 

The Department considered 

commenters’ concerns that the potential 

effect of the new rule to require new 

configurations of existing models to be 

marked under the new marking 

requirements would impose substantial 

costs (such as the cost of making new 

molds to conform with the new 

requirements) on existing product lines 

that are not otherwise being modified. 

ATF considered these comments in light 

of the public safety interest in ensuring 

appropriate markings. Because ATF has 

the capacity to successfully trace the 

many hundreds of thousands of 

grandfathered firearms and will be able 

to continue to trace them even if there 

is a change in configuration, the 

Department removed ‘‘and 

configuration.’’ The revised provision 

therefore allows manufacturers to mark 

the same information on the same 

component defined as a ‘‘frame or 

receiver’’ as they did before the effective 

date of the rule, which includes the 

specific component of a weapon or 

device (and variants thereof) that ATF 

classified as the frame or receiver before 

the rule becomes effective. 

In regard to the comment on how the 

rule applies to new designs of firearms 

already in inventory, the final rule 

makes clear that the new marking 

requirements apply only to frames or 

receivers manufactured after the 

effective date of the final rule. This 

change will help accommodate changes 

in firearms technology while still 

ensuring that the frames or receivers 

with new modular designs are marked 

and can be traced. The new marking 

information substantively differs from 

the current marking requirements for 

firearms (other than PMFs) only in that 

the licensee’s name, city and State, or, 

alternatively, the licensee’s name (or 

recognized abbreviation) and 

manufacturer’s or importer’s 

abbreviated FFL number, must be 

placed on the frame or receiver in 

addition to the unique identification 

number, and cannot be placed on the 

slide or barrel. The reason for requiring 

all this information to be placed on the 

frame or receiver is that the associated 

licensee information, when marked on 

the slide or barrel as currently allowed, 

can be separated from the serialized 

frame or receiver in limited 

circumstances, rendering the firearm 

untraceable. A unique identification 

number, or traditional serial number, on 

the frame or receiver alone may not be 

sufficient because ATF may not know 

which licensee produced the firearm or 

the location where the traceable records 

are located. Manufacturers may, 

however, seek a marking variance from 

the Director if they find it difficult to 

transition to these marking requirements 

for new frame or receiver designs. 

i. Voluntary Classifications of Firearms 

and Armor Piercing Ammunition 

Comments Received 

A few commenters said the way that 

§ 478.92(c) is drafted does not obligate 

ATF to respond to a classification 

request, which could allow the agency 

to ignore a classification request and 

stall advancement of new products or 

technologies deemed politically 

undesirable. Commenters also noted 

that there is no requirement that the 

agency notify the submitter that the 

agency has accepted or rejected the 

classification request. Therefore, the 

commenters advocated that there should 

be a requirement that determinations be 

rendered within three months or that 

some other reasonable time-frame be 

added to the proposed 27 CFR 478.92(c). 

One commenter suggested adding 

language deeming the submitted 

product compliant as proposed by the 

requestor if ATF fails to respond within 

a specified time frame. It also 

recommended deleting, for purposes of 

flexibility, the prohibition on rendering 

a determination unless a firearm 

accessory or attachment is installed on 

the firearm(s) for which it is designed 

and intended to be used. Further, it 

proposed adding a sentence stating that 

an ATF determination is an opinion and 

does not have the force of law. Another 

commenter claimed that the codification 

of the classification letter process fails 

to abide by the Attorney General’s 

memorandum entitled ‘‘Prohibition on 

Improper Guidance Documents.’’ 

Commenters also said that it is 

unrealistic to believe that a 

manufacturer would have the ability to 

submit marketing or instruction 

materials with a classification request 

per the proposed rule, as oftentimes 

these materials are developed just before 

a product launches. They also 

questioned whether a prior 

determination becomes invalid if 

instructions or marketing materials 

change, thereby triggering submission of 

another request and reverting the 

product to the proposed rule’s default 

marking requirements pending a new 

determination. Other commenters 

argued that asking manufacturers to 

submit instructions and manuals is not 

only a huge administrative burden but 

also would lead to less production and 

fewer submissions of instructions, as it 

seemed possible that ATF could use the 

guides against the manufacturers. The 

lengthy waits and delays that 

manufacturers already face under the 

current process, according to the 

commenter, would only be compounded 

under the NPRM. All this would have 

the unintended consequence of creating 

a disincentive for manufacturers to 

develop new, safer, and more reliable 

firearms because of a heavy regulatory 

burden. 

Some commenters further opined that 

ATF’s classification process allows the 

agency to play favorites, pick 

technologies, and influence court 

decisions without going through the 

APA. They asserted that the proposed 

rule actually incentivizes technical 

developments that will create an even 

worse black market of untraceable 

firearms. 

One commenter suggested altering the 

last sentence of proposed 27 CFR 

478.92(c), to state that ATF 

classifications of frames or receivers 

issued after publication of the final rule 

are not considered authoritative with 

regard to other samples, designs, 

models, or configurations of frames or 

receivers. Adding this language, the 

commenter said, would allow a licensee 

to leverage a previous hardware 

determination and make it more 

transparent to industry that a previous 

hardware determination is an acceptable 

practice if the design was in existence 

prior to the publication date of the final 

rule. 

Department Response 

The Department agrees with 

commenters that the rule, as proposed, 

would have resulted in more voluntary 

classification requests to ATF to 

determine which part of a new design 


jspears on DSK121TN23PROD with RULES2
24710 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

134See Memorandum for the Heads of All 

Department Components, Re: Issuance and Use of 

Guidance Documents by the Department of Justice 

at 1 (July 1, 2021), available at https://

www.justice.gov/opa/page/file/1408606/download 

(defining ‘‘guidance document’’ as ‘‘a statement of 

general applicability’’ that does not include either 

‘‘adjudicatory or administrative actions’’ or 

‘‘rulings’’); E.O. 13992, 86 FR 7049 (Jan. 20, 2021); 

see also Processes and Procedures for Issuance and 

Use of Guidance Documents, 86 FR 37674 (July 16, 

2021) (revoking 28 CFR 50.26 and 50.27). 

of a firearm was ‘‘the’’ frame or receiver. 

This would have increased the burden 

on both licensees and ATF. The 

Department agrees with commenters 

that the statute is best read to focus on 

a single portion of a weapon as ‘‘the’’ 

frame or receiver. Accordingly, the 

Department establishes a new definition 

of ‘‘frame or receiver’’ as described to 

focus on a single portion of a weapon 

for ‘‘frames’’ of handguns; ‘‘receivers’’ 

for rifles, shotguns, and projectile 

weapons other than handguns; and 

‘‘frames’’ or ‘‘receivers’’ for firearm 

muffler or silencers. The final rule does 

not adopt the proposed definitional 

supplement entitled ‘‘Split or Modular 

Frame or Receiver.’’ The Department 

agrees that not finalizing this provision 

will substantially reduce or eliminate 

the need for persons to submit 

classification requests to ATF to help 

them determine which portion of a 

weapon is the frame or receiver of a 

particular model. 

With regard to other types of firearm 

classification requests, ATF has long 

accepted voluntary requests in 

furtherance of its mission to assist 

persons in complying with the 

requirements of the GCA and NFA as a 

public service. There is no statutory 

requirement for a person to submit such 

requests and likewise no requirement 

for ATF to act upon any such requests. 

Alternatively, anyone may seek private 

counsel to determine the person’s legal 

obligations under the Federal firearms 

laws and regulations. 

The Department disagrees with the 

suggestion to eliminate, for flexibility, 

the provision that states that the 

Director shall not issue a determination 

regarding a firearm which may be sold 

or distributed with an accessory or 

attachment unless it is installed on the 

firearm(s) in the configuration for which 

it is designed and intended to be used. 

The accessory or attachment itself must 

be attached to the weapon so that a 

proper firearm classification can be 

made under the GCA or NFA. 

The Department disagrees with the 

suggestion to add a sentence to 

individual ATF firearm classifications 

saying that the classification is an 

opinion that does not have the force of 

law. Firearm classifications are private 

letter rulings issued to a particular 

requestor with respect to a specific item. 

Saying that ATF classification letters do 

not have the force of law may mislead 

the requestor into believing that the 

statutes and regulations referenced 

therein, or possible administrative 

actions taken by ATF (e.g., one saying 

that the firearm cannot be returned 

because it would place the recipient in 

violation of law), are not required to be 

followed. The GCA and NFA, and their 

implementing regulations, clearly have 

the force and effect of law. Should a 

requestor ignore the classification letter 

and move forward to produce and sell 

or import items classified as firearms in 

violation of the GCA or NFA, the 

classification letter could be used to 

prove the willfulness of the violation in 

a criminal prosecution, administrative 

licensing or tax collection proceeding, 

or for seizure and forfeiture of 

unlawfully produced or possessed 

weapons. 

The Department also disagrees with 

the comment that codification of the 

classification letter process fails to abide 

by the memorandum of the Attorney 

General entitled ‘‘Prohibition on 

Improper Guidance Documents’’ (Nov. 

16, 2017), not only because 

classification letters are not ‘‘guidance 

documents,’’ but also because that 

memorandum was rescinded by the 

Attorney General by memorandum 

dated July 1, 2021, consistent with the 

President’s Executive Order entitled 

‘‘Revocation of Certain Executive Orders 

Concerning Federal Regulations’’ issued 

on January 20, 2021.134

The Department agrees with the 

comment that it may be burdensome for 

requestors to submit instructions, 

guides, and marketing materials with a 

classification request if those materials 

are not available at the time of 

submission. However, as explained in 

the rule, these items and materials are 

important for ATF to determine whether 

an unfinished, disassembled, or 

nonfunctional item or kit is a ‘‘firearm’’ 

subject to regulation under law. When 

sold or distributed with a partially 

complete, disassembled, or 

nonfunctional item or kit, they must be 

submitted. The final rule mitigates this 

burden by excluding from this 

requirement submission of such items 

and materials with firearm samples that 

are complete and assembled. 

The Department also agrees with the 

comment that the requestor of a 

voluntary classification of a specific 

component as a frame or receiver should 

be able to rely on that classification for 

other models and configurations the 

requestor manufactures. For this reason, 

the final rule makes clear that: (1) 

Determinations made by the Director 

identifying the specific component of a 

weapon as the ‘‘frame or receiver’’ as 

defined are applicable to variants 

thereof; and (2) an ATF classification of 

a specific component as the ‘‘frame’’ or 

‘‘receiver’’ is applicable to or 

authoritative with respect to any other 

sample, design, model, or configuration 

of the same weapon so that the 

requestor does not need to submit 

additional requests for future variants. 

In addition, defining the term ‘‘frame or 

receiver’’ in a more limited manner in 

the final rule will reduce or eliminate 

the need for industry members to 

voluntarily request a classification from 

ATF when deciding which particular 

component of a weapon is the frame or 

receiver, thereby reducing 

manufacturing costs. 

5. Concerns With Recordkeeping 

Requirements 

a. Acquisition and Disposition Records 

Comments Received 

Several FFLs stated they would have 

problems with recordkeeping and 

inventory if there is more than one 

frame or receiver. They claimed that 

paperwork and tracking would be very 

burdensome because parts swapping 

and replacements would result in 

multiple inventory entries. Likewise, 

many industry members asserted that 

serialization of multiple frames or 

receiver parts would create 

recordkeeping ‘‘havoc.’’ One commenter 

offered a hypothetical: Assume that ATF 

determines that a receiver has three 

separate parts, each of which must be 

serialized, and assume all three parts are 

made by the same manufacturer. If 

receiver part A is made on March 1, 

receiver part B is made on September 5, 

and receiver part C is made on 

December 8, the commenter was unsure 

which date would be the date of 

manufacture if recorded in a single 

entry. Or, if the dates were recorded in 

separate entries, the commenter stated 

this would be alarming because there 

would be duplicate serial numbers 

recorded for one firearm. Finally, the 

commenter asked whether, when all 

three parts were finally assembled to 

make a full receiver, would that action 

require another record, and if so, what 

would be that date of manufacture. 

Additionally, FFLs asserted it would 

be impossible to comply with the 

marking requirements because there is 

no compatible software they can use for 

recordkeeping and inventory. A major 

manufacturer stated that its current 

electronic business suite, which is 

responsible for tracking all parts and 

product inventory and for generating the 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24711 

A&D records, is inherently incompatible 

with multiple serial numbers per 

firearm (whether matching or nonmatching). It further stated it was not 

aware of a viable solution available to 

adapt this system in a way that would 

allow for tracking of multiple serial 

numbers per serialized item. This 

sentiment was echoed by several 

companies that highlighted the 

logistical problems with trying to keep 

track of multiple serial numbers on 

numerous frames or receivers. 

Another major manufacturer stated it 

would take years to test and change its 

already highly customized software 

suite to comply with the rulemaking. Its 

systems, it said, are not equipped to (1) 

process or manufacture firearms with 

more than one serialized component; (2) 

serialize and track more than one 

component with the same serial 

number; (3) associate more than one 

serial number with a complete firearm 

the company otherwise acquires; (4) 

generate the required A&D records; or 

(5) ‘‘update’’ a serial number to reflect 

marking of a PMF. The company stated 

it could not comply with the proposed 

rule and explained how trying to 

comply would be costly and disruptive 

to its manufacturing lines. These types 

of cost estimates provided by various 

companies are described further below. 

See Section IV.B.13 of this preamble. 

Manufacturers also pointed out an 

inconsistency between the proposed 

change to § 478.123(a), which would 

require manufacturers to record the 

serial number and other required 

information ‘‘not later than the close of 

the next business day following the date 

of manufacture or other acquisition,’’ 

and proposed § 478.92(a)(1)(v), which 

would require manufacturers to 

‘‘identify a complete weapon . . . no 

later than seven days following the date 

of completion of the active 

manufacturing process, or prior to 

disposition, or whichever is sooner.’’ 

They asked how they can record the 

serial number and other information on 

a manufactured firearm by close of the 

next business day if it is not required to 

be identified for seven days from 

completion of its manufacture. 

Other industry members raised 

concerns about recording and 

reconciling frames or receivers that 

could be ‘‘manufactured or acquired’’ 

prior to the time period in which the 

required markings must be applied. 

These types of firearms (e.g., a fully 

machined, unserialized frame or 

receiver) could be numerous, and it 

appeared to commenters that ATF 

expected manufacturers to list these 

firearms that have no identifying 

information with an ‘‘NSN’’ serial 

number. This, according to commenters, 

would create difficulties because the 

manufacturer would have to keep track 

of unserialized parts in the A&D records 

and, if any of those firearms were 

destroyed prior to serialization, the 

manufacturer would have no way to 

identify which frame or receiver 

corresponded to each recorded NSN 

entry in the manufacturer’s records. 

Commenters worried that this would 

result in countless recordkeeping errors 

and that theft/loss reporting of 

unserialized parts would be exceedingly 

difficult if not impossible. One 

suggested that a clear statement be 

added in the final rule that frames or 

receivers need not be ‘‘acquired’’ by 

manufacturers prior to marking if the 

parts being used in the manufacturing 

process could address this concern. 

Similarly, commenters stated that ATF 

Ruling 2012–1, which provides a 

manufacturer seven days following the 

date of completion of a firearm (or frame 

or receiver to be shipped or disposed of 

separately) to both mark and record the 

identifying information in its records, 

should be retained. 

Several manufacturers contended that 

the ‘‘commercial record’’ exception in 

proposed § 478.123(a), which would 

exempt manufacturers from recording 

the manufacture or acquisition of a 

firearm no later than the close of the 

next business day so long as they held 

a commercial record with relevant 

information, is irrelevant and would 

never apply. They argued that a 

‘‘commercial record’’ is a record of 

transaction between a transferor and 

transferee and that internal 

manufacturer records are not 

‘‘commercial records.’’ Therefore, they 

argued, the exemption from the next day 

recording requirement and allowance of 

up to seven days would never apply. 

They made similar arguments that the 

‘‘commercial record’’ exception would 

also not apply for repair or replacement 

requests, thus making it impossible to 

comply with the next day business rule. 

Accordingly, they requested that the 

current seven-day deadline be retained. 

Department Response 

Because the Department agrees with 

commenters that the definition of 

‘‘firearm’’ in 18 U.S.C. 921(a)(3)(B) is 

best read to mean a single part of a 

weapon as being the frame or receiver, 

the final rule adopts three subsets of the 

proposed definitions of ‘‘frame or 

receiver’’—‘‘frame’’ for handguns and 

variants thereof; ‘‘receiver’’ for rifles, 

shotguns, and projectile weapons other 

than handguns and variants thereof; and 

‘‘frame’’ or ‘‘receiver’’ for firearm 

muffler or silencer devices. The more 

limited definitions adopted in the final 

rule should address the costs and 

software problems that commenters 

raised. 

The Department also agrees with 

commenters who pointed out the 

inconsistency between the marking and 

recordkeeping requirements for 

manufacturers. The Department agrees 

that the time period should be the same 

and has clarified that markings be 

placed, and firearms be recorded, no 

later than the seventh day following the 

date of manufacture or other acquisition 

for non-NFA weapons and the frames or 

receivers of such weapons. Likewise, to 

be consistent with the recordkeeping 

and ATF Form 2 submission 

requirements, NFA weapons and parts 

defined as firearms must be marked and 

recorded, and Form 2 submitted, no 

later than close of the next business day 

after manufacture. The Department also 

agrees that the commercial record 

provision is not applicable to most 

manufacturers and that providing the 

seven-day grace period to both mark and 

record makes the commercial record 

allowance for non-NFA weapons that 

are manufactured unnecessary. For 

these reasons, that provision has been 

amended in the final rule to apply only 

to NFA weapons that are otherwise 

acquired commercially. 

b. Recordkeeping for ‘‘Privately Made 

Firearms’’ 

Comments Received 

One manufacturer stated that it did 

not understand how FFLs are to record 

PMFs that are marked in accordance 

with State laws (e.g., Connecticut), 

which have different requirements for 

assignment and structure of a serial 

number. 

Department Response 

Under the final rule, the licensee 

marking the frame or receiver of a PMF 

must place the licensee’s abbreviated 

license number (also known as the 

‘‘RDS Key’’) as a prefix before the 

unique identification number originally 

placed by the maker of the PMF that 

will be adopted by the licensee. The 

adopted markings must otherwise meet 

the marking requirements. This 

requirement allows ATF to trace the 

firearm to a particular licensee. If a State 

has issued a unique number that must 

be placed on a firearm, then the 

licensee’s abbreviated FFL number 

would be added as a prefix to that 

number if the licensee is going to accept 

that firearm into inventory. Again, 

nothing in this rule requires a licensee 

to accept a PMF into inventory or to 


jspears on DSK121TN23PROD with RULES2
24712 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

135See ATF Rul. 2009–1 (‘‘Any person who is 

engaged in the business of . . . engraving firearms 

. . . must be licensed as a dealer, which includes 

a gunsmith, under the Gun Control Act.’’). 

mark (non-NFA) PMFs on behalf of 

unlicensed persons. 

c. Record Retention Burden 

Comments Received 

Generally, commenters opposed the 

requirement that FFLs retain their 

records indefinitely until they 

discontinue their business, arguing that 

doing so would be burdensome and 

costly. Some pointed to the cost and 

burden on gunsmiths if many of them 

had to become licensees in order to 

mark PMFs. Those gunsmiths would 

then be subject to all the recordkeeping 

requirements imposed upon FFLs. Other 

commenters also expressed concern that 

having FFLs retain their records 

indefinitely would raise privacy 

concerns and subject FFLs to potential 

liability. FFLs, they argued, are subject 

to break-ins, both physical and cyber. 

Consequently, criminals could access 

ATF Form 4473s, use them to target 

unsuspecting firearms owners, and steal 

their firearms. 

Department Response 

The Department disagrees that the 

record retention rule is unreasonably 

burdensome; raises additional privacy 

concerns; increases the probability of 

break-ins; or exacerbates the deleterious 

effects of break-ins that do occur. At 

present, licensees are required to 

maintain their records of acquisition 

and disposition for at least 20 years. The 

Attorney General in this rule is 

exercising his authority under 18 U.S.C. 

923(g)(1)(A) and (g)(2) to extend the 20- 

year retention period for licensees so 

that their records are not destroyed. The 

rule allows ‘‘closed out’’ paper records 

that are more than 20 years old to be 

stored in a separate warehouse, which 

would be considered part of the 

business or collection premises for this 

purpose and would be subject to 

inspection in accordance with 18 U.S.C. 

923(g)(1) and 27 CFR 478.23. 

Alternatively, those paper records may 

be turned in to ATF if the licensee 

voluntarily chooses to discontinue its 

business or licensed activity for which 

those records were maintained, 

pursuant to 18 U.S.C. 923(g)(4) and 27 

CFR 478.127, even if it subsequently 

obtains a new license. 

With regard to persons who may 

become engaged in the business as 

gunsmiths so they can mark firearms, 

such persons have always been required 

by law to be licensed and maintain 

records of firearms they take into 

inventory for gunsmithing work, 

including engraving firearms.135 This 

rule clarifies that licensed gunsmiths do 

not need to be re-licensed as 

manufacturers for the sole purpose of 

engraving or otherwise marking PMFs. 

Additionally, in response to comments, 

the final rule reduces costs by clarifying 

that licensees may have firearms 

engraved on-the-spot by any person 

under the direct supervision of the 

licensee (i.e., without the engraver 

taking the firearm into an inventory) 

provided the marking requirements are 

met. 

d. Record Retention Impact on Public 

Safety 

Comments Received 

Some commenters argued that 

requiring FFLs to maintain their records 

indefinitely (instead of for the current 

20-year period) serves no purpose. They 

asked ATF to produce evidence that 

there is a statistically significant number 

of instances where a crime involved a 

firearm purchased outside the 20-year 

window to justify the change; further, 

they doubted that Form 4473s from over 

20 years ago would be helpful in solving 

crimes. Other commenters stated that 

sales records rarely help solve cases and 

claimed that tracing has been known not 

to work. Many challenged the 

usefulness in changing the retention of 

record requirement, stating that the 

average time-to-crime for recovered 

firearms is less than 10 years and that 

ATF and other entities have previously 

said that a firearm is untraceable after 5 

years. At least one commenter opined 

that the retention period should be 

shortened to seven years. 

Department Response 

The Department disagrees with 

commenters who said that the record 

retention requirement serves no 

purpose. Firearms are generally durable 

weapons that last many decades, and 

their lethality and potential use in crime 

does not diminish over time. As 

explained in this rule, firearms have 

been traced to retailers who destroyed 

numerous records that were older than 

20 years, but those traces could not 

successfully be completed. The National 

Tracing Center (‘‘NTC’’) conducted an 

analysis of all trace requests submitted 

between January 1, 2010, and December 

31, 2021, that were closed under a 

particular code in the tracing system 

indicating the FFL specifically informed 

ATF that it did not have records for that 

firearm because the records were more 

than 20 years old and had been 

destroyed. A total of approximately 

16,324 traces, or 1,360 on average per 

year, could not be completed during this 

time period because the records had 

been destroyed. Of these total 

unsuccessful traces, approximately 182 

of the traces were designated as 

‘‘Urgent,’’ 1,013 were related to a 

homicide or attempted homicide (not 

including suicide), and 4,237 were 

related to ‘‘Violent Crime.’’ Further, 

with the advancement of electronic 

scanning and storage technology, 

maintaining old records is not as 

difficult or costly as it was when ATF 

first allowed records over 20 years old 

to be destroyed in its 1985 rulemaking. 

See 50 FR at 26702. 

e. Alternatives to Record Retention 

Requirement 

Comments Received 

One commenter, who believed the 

extended recordkeeping to be a burden, 

stated that ATF needs to be consistent 

in its use of language. The commenter 

cited the difference in phrasing between 

§ 478.129(b)—‘‘until business is 

discontinued’’—and § 478.129(e)— 

‘‘until business or licensed activity is 

discontinued.’’ The commenter 

questioned the meaning of the latter 

phrase, asking if it refers to the actual 

closing down or the lapsing of a specific 

license. This could impact high volume 

dealers in their decision to either renew 

a current license or to allow it to lapse 

and apply for a new license, as a means 

of relieving the burdensome 

recordkeeping requirements. If ATF is 

purposefully using the different phrases, 

the commenter asked ATF to provide 

more clarity. 

Department Response 

The Department agrees with the 

comment that discontinuance of 

business includes cessation of ‘‘licensed 

activity’’ or lapse of a specific license, 

and that the language of proposed 

§ 478.129(b) and proposed § 478.129(d) 

should have included the same language 

as paragraph (e). The final regulatory 

text has been amended accordingly. 

6. Clarity on Unlawful Conduct 

Comments Received 

Commenters objecting to the proposed 

inclusion of ‘‘weapon parts kits’’ in the 

definition of ‘‘firearm’’ expressed 

concern about the expansion of conduct 

that would be considered unlawful. In 

the NPRM, ATF explained it was 

clarifying that weapon parts kits are 

included under the definition of a 

‘‘firearm’’ so that FFLs who sell these 

kits to unlicensed individuals would be 

required to complete the ATF Form 

4473, background check, and 

recordkeeping requirements. 86 FR at 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24713 

136Further, under 18 U.S.C. 1715, except for 

customary trade shipments between licensees, 

firearms capable of being concealed on the person, 

including handgun frames or combinations of parts 

from which handguns can be assembled, are 

prohibited from being mailed by the United States 

Postal Service. 39 CFR 211.2(a)(2), (a)(3); United 

States Postal Service, Publication 52—Hazardous, 

Restricted, and Perishable Mail at sec. 432.2(d) (Oct. 

2021), available at https://pe.usps.com/text/pub52/ 

pub52c4_009.htm (last visited Mar. 23, 2022). 

137See 26 U.S.C. 4181 (imposing on the 

manufacturer, producer, or importer an excise tax 

of 10 percent (pistols and revolver) or 11 percent 

(other firearms) on the sale prices of firearms 

manufactured, produced, or imported, including 

complete, but unfinished, weapon parts kits); Rev. 

Rul. 62–169, 1962–2 C.B. 245 (kits that contain all 

of the necessary component parts for the assembly 

of shotguns are complete firearms in knockdown 

condition even though, in assembling the shotguns 

the purchaser must ‘‘final-shape,’’ sand, and finish 

the fore-arm and the stock); Internal Revenue 

Service Technical Advice Memorandum 8709002, 

1986 WL 372494, at *4 (Nov. 13, 1986) (for 

purposes of imposing Firearms Excise Tax it is 

irrelevant whether the components of a revolver in 

an unassembled knockdown condition are sold 

separately to the same purchaser in various related 

transactions, rather than sold as a complete kit in 

a single transaction); cf. Rev. Rul. 61–189, 1961–2 

C.B. 185 (kits containing unassembled components 

and tools to complete artificial flies for fisherman 

were sporting goods subject to excise tax); Hine v. 

United States, 113 F. Supp. 340, 343 (Ct. Cl. 1953) 

(kits consisting of a fishing rod ‘‘blank’’ and 

everything necessary to complete a fishing rod were 

subject to excise tax having ‘‘reached the stage of 

manufacture or development where they became 

recognizable as . . . rods . . . even though there 

remained one or more finishing operations to be 

performed’’). The Alcohol and Tobacco Tax and 

Trade Bureau of the U.S. Department of the 

Treasury should be consulted with respect to the 

imposition of Firearms and Ammunition Excise 

Tax. See U.S. Dep’t of the Treasury, Manufacturers 

and Producers (Apr. 17, 2018), available at https:// 

www.ttb.gov/firearms/manufacturers (last visited 

Mar. 23, 2022). 138See, e.g., United States v. Evans, 928 F.2d 858, 

859–62 (9th Cir. 1991) (affirming convictions for 

conspiracy to cause, and aiding and abetting, the 

possession of unregistered machineguns where one 

defendant sold parts kits containing all component 

parts of Sten machineguns except receiver tubes 

and the other sold customers blank receiver tubes 

along with detailed instructions on how to 

complete them). 

27726. ATF further explained in 

footnote 45 of the NPRM that persons 

engaged in the business of selling or 

distributing weapon parts kits cannot 

avoid licensing, marking, 

recordkeeping, or other requirements to 

which FFLs are subject ‘‘by selling or 

shipping the parts in more than one box 

or shipment to the same person, or by 

conspiring with another person to do 

so.’’ Id. at 27726 n.45. 

Commenters claimed that individuals, 

producers, and retailers will be left 

guessing what constitutes a weapon 

parts kit because, in the commenters’ 

opinion, it was unclear from the 

proposed definition how many orders 

could constructively constitute a 

weapon parts kit over a period of time. 

They worried that a simple misstep, 

such as an individual selling 

components or tools that could be part 

of a weapon parts kit, could result in 

prison time if the individuals selling the 

components or tools could be viewed as 

having conspired with other dealers or 

manufacturers to sell a complete 

weapon parts kit. 

Department Response 

In response to some commenters who 

expressed confusion concerning 

footnote 45 of the NPRM, 86 FR at 

27726, as to what conduct is acceptable 

with respect to the sale or distribution 

of weapons parts kits or aggregations of 

firearm parts, the Department reiterates 

that title 18 of the U.S. Code includes 

Federal felony violations that can apply 

to circumstances involving the final 

rule’s requirements. These include 

criminal prohibitions on: Engaging in 

the business of importing, 

manufacturing, or dealing in firearms 

without a license (18 U.S.C. 

922(a)(1)(A)); engaging in the business 

of importing or manufacturing 

ammunition without a license (18 

U.S.C. 922(a)(1)(B)); aiding and abetting 

or causing such conduct to occur (18 

U.S.C. 2); and conspiring with another 

to engage in such conduct (18 U.S.C. 

371).136 Additionally, persons who 

manufacture and sell unassembled 

weapons or weapon parts kits in 

‘‘knockdown condition’’ (i.e., 

unassembled but complete as to all 

component parts) cannot structure 

transactions to avoid paying Firearms 

Excise Tax on their sales price.137 In 

sum, persons cannot undermine these 

requirements and prohibitions by 

working with others or structuring 

transactions to avoid the appearance 

that they are not commercially 

manufacturing and distributing 

firearms.138

7. Stifles Technological Innovation 

Comments Received 

Several commenters opposed the 

NPRM because they believed that it 

would discourage technological 

innovation and ignored the realities of 

the design and engineer process. 

Commenters stated that companies or 

new entrants to the market will 

generally manufacture in accordance 

with the ‘‘safe-harbored’’ products 

identified within the proposed 

definitions because they fear the risk of 

non-compliance and the resulting 

potential for liability. 

Department Response 

The Department disagrees that the 

rule will stifle innovation. Because of 

this rule, licensees will have a better 

understanding of which portion of a 

weapon is the frame or receiver with 

respect to current and new designs and 

will be able to mark those firearms 

without seeking guidance from ATF. By 

providing much needed clarity as to 

what is a frame or receiver, ATF is 

encouraging innovation by providing a 

framework under which new ideas and 

technology can develop. With the 

advancement of split and modular 

firearm designs in which components 

may become separated, these updates 

are necessary to identify firearms for 

inventory control and to allow tracing. 

To alleviate the cost to add the 

associated licensee information on 

existing frames or receivers, the final 

rule requires only new designs (i.e., 

those that are functionally modified or 

altered) to be identified with the 

associated licensee’s name, city and 

State, and serial number or, 

alternatively, the licensee’s name and 

the serial number beginning with an 

abbreviated license number as a prefix 

to the unique identification number. 

Again, under this final rule, there would 

be only one frame or receiver of a given 

weapon. 

8. Does Not Enhance Public Safety 

Comments Received 

Thousands of commenters opposed 

the changes in the NPRM, arguing that 

the NPRM will not enhance public 

safety and that adding serial numbers 

will do nothing to reduce crime. Some 

commenters stated that ATF presented 

no evidence that definitively links 

firearm part serialization with 

statistically significant violent crime 

reduction and failed to show evidence 

that serialized firearms clearly assist in 

law enforcement investigations that 

result in the return of stolen or lost 

firearms. 

Commenters opposed to the rule 

claimed that PMFs or ‘‘ghost guns’’ are 

not generally used by criminals because 

they are too expensive to build and that 

firearms make their way into the hands 

of criminals through theft or other 

activity. In the experience of at least one 

commenter, 3D printing of firearms can 

be a time intensive process where a 

single print of a handgun can take 

anywhere from 48 to 72 hours to finish. 

Further, it can take several tries to get 

a print done, which can take a period 

of several days. This time investment, in 

the commenter’s opinion, makes it less 

likely that criminals are using 3D 

printing to create firearms they intend to 

use in crimes. 

Further, commenters wrote that, even 

if ATF required markings on PMFs, it is 

well known that criminals simply 

obliterate serial numbers. Numerous 


jspears on DSK121TN23PROD with RULES2
24714 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

commenters also pointed to ATF’s 

Motion to Dismiss in the California v. 

ATF lawsuit, where the State of 

California asked the Federal court to 

direct ATF to vacate its determinations 

that unfinished pistol frames and 

receivers are not subject to the same 

regulations as other firearms and to 

direct ATF to classify so-called ‘‘80%’’ 

frames and receivers as firearms subject 

to Federal firearms statutes and 

regulations. Paraphrasing ATF’s 

arguments from the agency’s Motion to 

Dismiss, commenters stated that ATF 

argued ‘‘eight such crimes out of the 1.1 

million violent crimes committed in the 

relevant six-year-period is a far cry from 

an overwhelming wave that would 

cause a State injury sufficient to confer 

standing . . . . Nor can California 

plausibly plead that those crimes would 

not have occurred with traditional, 

serialized firearms.’’ Likewise, 

commenters also took issue with the 

data ATF presented in the NPRM 

regarding the 23,906 PMFs submitted 

for tracing from 2016 through 2020. 

They stated that ATF needed to provide 

context for the data it presented. They 

claimed the data presented is not 

sufficient to demonstrate that PMFs are 

actually used in crimes and that ATF 

has been able to argue only that 

‘‘suspected’’ PMFs were ‘‘reported’’ to 

be present in ‘‘potential’’ crime scenes. 

Further, they opined that the PMFs 

recovered might actually involve 

hundreds of factory-made firearms with 

the serial numbers removed. 

Other commenters countered ATF’s 

data by citing a Bureau of Justice 

Statistics’ (‘‘BJS’’) publication to try to 

show that criminals do not use PMFs. 

See BJS, Source and Use of Firearms 

Involved in Crimes: Survey of Prison 

Inmates, 2016 (Jan. 9, 2019), available at 

https://bjs.ojp.gov/library/publications/ 

source-and-use-firearms-involvedcrimes-survey-prison-inmates-2016. In 

that survey, 287,400 surveyed prisoners 

had possessed a firearm during their 

offense. Among these, more than half 

(56 percent) had either stolen it (6 

percent), found it at the scene of a crime 

(7 percent), or obtained it off the street 

or from the underground market (43 

percent). Most of the remainder (25 

percent) had obtained it from a family 

member or friend as a gift. The report 

said only 7 percent of felons surveyed 

purchased their firearms legally through 

an FFL. In sum, commenters claimed 

that the NPRM is a solution in search of 

a problem and is not addressing an 

actual problem. 

Department Response 

As discussed in the Section II.A of 

this preamble, the submission of PMFs 

reported for tracing by law enforcement 

is increasing at an exponential rate, 

especially over the last three years, 

which is more recent than the 2016 BJS 

data relied on by commenters. Further, 

unlike commercially produced firearms, 

it is difficult for licensees to account for 

PMFs in their inventories and to report 

thefts or losses of those weapons to law 

enforcement and insurance companies. 

The current technology for privately 

making firearms, including 3D printing, 

is continually improving, and the 

Department and ATF have the authority 

and obligation to promulgate regulations 

to implement the GCA in light of the 

public safety goals of that statute. 

The Department disagrees that PMFs 

can statistically be compared to firearms 

that have undergone background 

checks, or with firearms recovered that 

have been marked with serial numbers 

and other identifying information. As 

explained in this rule, PMFs are being 

assembled from parts without 

background checks. They are not yet 

being acquired through the primary 

market in quantities like commercially 

produced firearms. But they are easily 

acquired by persons prohibited by law 

from receiving or possessing firearms, 

and they therefore pose a significant 

threat to public safety. Moreover, unlike 

other firearms recovered by law 

enforcement, PMFs are far more difficult 

for law enforcement to trace when 

recovered at a crime scene because they 

lack serial numbers and other 

identifying markings. With the 

advancement of firearms technology, 

PMFs will, over time, eventually make 

their way into the primary market as 

they become more reliable, and where 

they can be marketed broadly, pawned, 

or repaired. 

9. Tracing Efforts Hindered 

Comments Received 

Commenters asserted that the NPRM 

will not enhance public safety because 

the new requirements will only make it 

more confusing for law enforcement 

officers when tracing firearms. 

Commenters stated that criminals could 

simply acquire two copies of the same 

model and interchange or swap parts, 

which would send law enforcement on 

a wild goose chase. Other commenters 

stated that individuals typically swap 

out upper and lower assemblies to 

alternate calibers or to use different 

barrels, which would lead to more than 

one serial number on the firearm. In 

these cases, an officer may find two or 

three different serial numbers and 

submit all the numbers to ATF for 

tracing, which would require ATF to 

contact multiple manufacturers, 

distributors, and retailers, and possibly 

multiple transferees who purchased 

firearms. 

Department Response 

The Department agrees with 

commenters who said that, under the 

proposed rule, law enforcement may 

find it more difficult to trace firearms 

with more than one serial number. For 

this reason, the final rule accepts 

commenters’ suggestions asserting that 

the term ‘‘frame or receiver’’ should be 

defined to mean only a single housing 

with one unique serial number that is 

not duplicated on any other firearm. 

The Department agrees with 

commenters that doing so will be less 

costly for licensees to mark and record, 

and for law enforcement to trace 

firearms involved in crime. Therefore, 

the Department has defined the term 

‘‘frame or receiver’’ to focus on only one 

part that is marked on a particular 

weapon or firearm muffler or silencer. 

In the case of a multi-piece frame or 

receiver, however, the final rule makes 

clear that, if there are two or more 

similar subparts that make up a multipiece frame or receiver, then those 

subparts would be marked with the 

same serial number and associated 

licensee information. Thus, there should 

be very few circumstances in which 

there are more than one unique serial 

numbers placed on a weapon (e.g., a 

remanufactured or imported firearm 

where the manufacturer or importer 

chooses to mark its own serial number 

rather than adopting an existing serial 

number). 

10. Punishes Law-Abiding Citizens 

Comments Received 

Numerous commenters objected to the 

NPRM because they believed it could 

turn law-abiding citizens into felons and 

would only serve to punish hobbyists 

who build their own firearms. 

Concerned that firearms in their 

possession would have more than one 

frame or receiver and therefore would 

need more than one part marked, 

commenters opposed to the rule 

expressed concern that they would be 

automatic felons once the regulation 

becomes effective. For instance, 

commenters stated that, if the upper for 

an AR–15 is considered a receiver under 

the rule, then thousands of law-abiding 

citizens who own these items would 

become felons overnight. Other 

commenters similarly questioned 

whether they will have violated the 

NFA or GCA if they sell or purchase an 

unmarked partially completed weapon 

parts kit after the final rule is enacted. 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24715 

139See footnotes 33 and 39, supra. 

Department Response 

The Department disagrees that this 

rule turns law-abiding citizens into 

felons and only serves to punish 

hobbyists who build their own firearms. 

Nothing in this rule prevents unlicensed 

law-abiding citizens and hobbyists from 

making their own firearms by using 

commercially produced parts or by 

using 3D printers; or from transferring 

PMFs to others as long as they are not 

engaged in a business or activity 

requiring a license. If such persons wish 

to engage in the business of 

manufacturing, importing, or dealing in 

firearms, they must obtain a license like 

any other manufacturer, importer, or 

dealer. Of course, private makers must 

abide by the Undetectable Firearms Act, 

18 U.S.C. 922(p); NFA requirements; 

and any applicable State and local laws 

that govern privately made firearms. 

With regard to commenters’ assertion 

that there would be more than one 

‘‘frame or receiver’’ on a given weapon, 

this final rule does not define that term 

in a manner that would result in more 

than one on a particular weapon. 

11. Impacts on Underserved and 

Minority Communities 

Comments Received 

Numerous commenters asserted that 

the NPRM is racist and would 

negatively impact the poor and minority 

communities. They requested that the 

rule either be rescinded or that a ‘‘racial 

equity analysis’’ be conducted to 

prevent any racially discriminatory 

outcomes. These types of commenters 

stated, for example, that the 

requirements for serial numbers will 

disproportionately impact the poor, 

elderly, and minorities and will place 

the nation’s citizens at increased risk 

from criminals. Other commenters 

stated their belief that the rule will 

result in more Black Americans being 

arrested, prosecuted, and incarcerated 

and thus will harm already vulnerable 

communities. Another commenter 

contended the proposed rule is at odds 

with the President’s equity initiatives in 

that, although the Administration is 

considering equity in pursuing policy 

changes to education, employment, and 

housing, this policy of promoting equity 

should also include ‘‘firearms equity.’’ 

The commenter indicated that increased 

costs to gun manufacturers under this 

proposal would not only affect small 

businesses but also would have a 

disparate impact on low-income 

citizens, who are disproportionately 

persons of color, according to the 

commenter. Accordingly, the 

commenter stated that ATF must 

provide data and a comprehensive 

analysis to prove that the NPRM does 

not unfairly and inequitably penalize 

any racial or ethnic group, nor harm any 

protected civil rights class. Further, the 

commenter argued that ATF should seek 

to increase gun affordability for lowincome citizens and increase gun 

ownership among disadvantaged 

people. 

Department Response 

The Department disagrees that 

additional racial equity analysis needs 

to be conducted on the rule or that this 

rule is inconsistent with equity 

initiatives of the Administration. This 

final rule implements the GCA, which 

regulates commerce in firearms. The 

GCA, in part, requires that all firearms 

manufactured, imported, and sold by 

FFLs, or transferred through FFLs, be 

marked with serial numbers in order to 

be traceable wherever those firearms are 

recovered by law enforcement 

nationally or internationally. A firearms 

trace provides an investigative lead to 

law enforcement regarding the identity 

of the unlicensed person who first 

purchased the firearm from a firearms 

retailer (or at retail from a manufacturer, 

importer, or wholesaler); the 

identification of that person does not 

automatically indicate that the person is 

a criminal. The GCA does not 

distinguish between communities in the 

United States; further, ATF is prohibited 

under Federal law from maintaining a 

registry of firearms or firearms owners, 

see 18 U.S.C. 926, with the exception of 

weapons subject to the NFA, and 

therefore ATF does not know who owns 

firearms, nor does it keep track of who 

builds their own PMFs. Accordingly, 

there is no way for ATF to anticipate or 

measure now or in the future how the 

rule would impact particular 

communities based on racial or socioeconomic distinctions. Lastly, it is not 

within the scope of the GCA, or the 

Department’s or ATF’s purview, to 

increase gun affordability for lowincome citizens and increase gun 

ownership among any particular group 

of people. For additional information, 

see Section IV.A.5.h of this preamble. 

12. Other Priorities and Efficiencies 

Comments Received 

Many commenters stated that the 

Department and ATF should not attack 

law-abiding citizens but should instead 

focus on real criminals and enforce the 

existing firearms laws. They stated that 

ATF should expand resources in the 

investigation and assistance of 

prosecution of weapons charges and 

more fully advise the courts on such 

technical issues. Other commenters 

stated that the government should 

devote resources to solving mental 

health issues or combating drugs on the 

street. Other commenters suggested that 

the government propose new sentencing 

guidelines for individuals who steal or 

utilize firearms in criminal activities 

rather than enact new rules that impact 

only law-abiding citizens. 

Department Response 

The Department agrees with 

commenters that mental health and 

drugs are important issues for the 

government to address, but disagrees 

that this rule improperly diverts ATF 

resources. To the contrary, the rule is 

absolutely necessary to allow ATF to 

focus its resources. The rule 

accomplishes this goal by helping to 

ensure that firearms recovered from 

crimes can be traced through licensee 

records using the information marked 

on the frame or receiver of each firearm. 

Not only do more traceable firearms 

lead to increased discovery and 

prosecutions of criminals, but they also 

provide ATF with key crime gun 

intelligence, such as firearm trafficking 

patterns through multiple sales reports, 

demand letters of licensees with a short 

‘‘time-to-crime,’’ and theft/loss 

reports.139

13. Concerns With the Economic 

Analysis 

a. Addressing an Externality 

Comments Received 

In the NPRM, ATF stated that this 

rule would address externalities. 86 FR 

at 27738. Commenters stated that 

externalities result from inefficiencies in 

market transactions. Commenters stated 

that ATF failed to address how 

criminals produce a negative externality 

by using an unmarked weapon when 

committing a crime. In addition, 

commenters stated that commercial 

activity should not be held responsible 

for any difficulties ATF experiences in 

enforcing Federal law. 

Department Response 

ATF concurs that this rule would not 

address externalities due to market 

inefficiencies; therefore, to avoid any 

confusion, the language in the NPRM 

that suggested that this rule would 

address a market inefficiency has been 

removed in the final rule. Regardless of 

this change, publication of this rule 

remains necessary to enforce the GCA 

and NFA. 


jspears on DSK121TN23PROD with RULES2
24716 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

b. Overall Costs 

Comments Received 

Many commenters stated that the 

costs that ATF attributed to the rule did 

not account for the full number of PMFs 

currently in circulation. They stated that 

there are as many as 20 million 

individuals or PMFs that would be 

affected by this rule. In addition, one 

commenter suggested that the overall 

cost estimate in the NPRM (which the 

commenter calculated to be seven cents 

per firearm for all firearms currently in 

circulation) was not a realistic cost 

estimate given the comprehensive 

changes being made to the industry as 

a whole. One commenter suggested that 

a low estimate of $45 to mark each 

firearm should make the overall cost 

estimate over $100 million. Another 

commenter believed that the increased 

cost to the consumer of five dollars per 

firearm is too low because this cost 

includes engraving, paperwork 

retention, legal services, and 

engineering, all of which would be 

necessary to achieve compliance with 

the new regulations. Several 

commenters stated that the 20-year 

estimate of $1.1 million is too low. One 

commenter stated that, if an ‘‘80%’’ 

receiver or frame sells for $100, the $1.1 

million estimate would mean that only 

550 receivers or frames were sold per 

year—a number the commenter believed 

was ‘‘impossibly low.’’ Commenters 

asserted that companies would suffer 

substantial losses or go out of business 

altogether. One commenter asked if 

businesses would be compensated if 

their actual costs were above the costs 

estimated in the rule. 

Some commenters suggested that 

requiring multiple serial numbers 

would also be cost prohibitive for 

manufacturers and make the rule 

economically significant. A commenter 

suggested that the manufacturing costs 

alone would be at least $400 million. 

Many commenters stated that ATF 

failed to compile data on unfinished 

receivers and kit sales and that ATF 

does not know how commerce would be 

affected by the rule change. One 

commenter stated that, to comply with 

new regulations, companies would need 

to seek legal advice and train employees 

on the regulations and form changes, 

which would exceed the cost estimate of 

$10 per company. 

One commenter wanted to know if 

ATF had considered how higher 

demand for determinations would affect 

the agency and the manufacturers 

awaiting these determinations. 

Additionally, this commenter wanted to 

know if ATF had considered the costs 

to Federal, State, and local agencies to 

train law enforcement to recognize 

items now classified as firearms and the 

increased workload on ATF to regulate 

firearms with multiple frames or 

receivers. 

One commenter stated that some 

individuals must drive long distances to 

reach an FFL. These trips are expensive 

and time consuming. Another 

commenter stated that the cost estimate 

for individuals was too low because it 

failed to consider the time and 

transportation costs of travel to an FFL 

to transfer parts, such as upper receivers 

or pistol slides, which the commenter 

believed would be required to be 

serialized under the rule. 

Department Response 

ATF agrees that the costs of the rule 

did not account for PMFs currently 

owned by law-abiding individuals, but 

this is because the rule does not affect 

individuals in possession of PMFs 

unless the individual tries to sell or 

otherwise dispose of the PMF though an 

FFL. ATF cannot agree with the 

commenter that there may be up to 20 

million PMFs in private circulation 

because ATF does not maintain any data 

that would allow for an estimate of the 

number of PMFs. In any event, PMFs, by 

definition, are not serialized by FFLs 

and would only need to be serialized if 

the individual with the PMF transfers it 

to an FFL. Nonetheless, ATF 

significantly revised its economic 

analysis in preparing the final rule to 

better reflect the rule’s impact on these 

affected populations. 

Where feasible, the Department has 

reduced some of the burdens on the 

regulated community. Rather than 

requiring multiple serial numbers, the 

final rule amends the proposed 

definition of ‘‘frame or receiver’’ to 

identify one part of a firearm to be the 

‘‘frame’’ or ‘‘receiver’’ that requires a 

serial number (with the exception of 

multi-piece frames or receivers that are 

composed of multiple modular subparts, 

which require placement of the same 

serial number and associated licensee 

information on those parts). Because 

there will almost always be one serial 

number per firearm under the final rule, 

no Federal, State, or local costs were 

considered for law enforcement to 

review firearms with multiple serial 

numbers. 

ATF concurs with the comment that 

entities will need to provide training to 

employees to ensure compliance when 

any new regulations are published. 

However, ATF disagrees that these costs 

should be considered under the rule. 

Activities such as training employees 

and obtaining legal opinions in response 

to a new regulation of this type are 

usual activities for complying with the 

regulatory requirements in this industry 

and are not treated as new costs 

associated with the rule. Where 

manufacturers have been granted 

determination letters for their firearm 

designs, these designs have been 

grandfathered to be excluded from the 

final rule, except for those 

determinations that a frame or receiver 

had not reached a stage of manufacture 

to be classified as a frame or receiver. 

Due to these changes and the revised 

definitions under the final rule, ATF 

does not anticipate that manufacturers 

and retailers of currently regulated 

firearms will incur significant costs 

from the publication of this final rule. 

c. Affected Populations 

Comments Received 

One commenter suggested that ATF 

underestimated the overall number of 

the affected populations because the 

number of public comments received on 

the proposed rule was more than the 

number of affected entities listed in the 

NPRM. One commenter stated that the 

total affected population should include 

all businesses that sell firearms 

components, not just makers of 

unfinished frames or receivers. One 

commenter stated that ATF failed to 

include ‘‘micro-scale’’ businesses that 

specialize in firearms customization for 

marksmanship competitions, and that 

many small businesses that sell 

semiautomatic pistol slides and 

accessories, which they believed would 

be reclassified as firearms by the final 

rule, would need to become licensed as 

dealers or manufacturers. 

Many commenters stated that the 

Regulatory Impact Analysis (‘‘RIA’’) did 

not account for the costs incurred by 

individuals. Many commenters 

estimated a total number of PMFs 

already in circulation and estimated that 

the cost for those currently in 

circulation would be millions of dollars. 

Some commenters stated that the NPRM 

should have included an estimate of the 

number of PMFs and unfinished 

receivers that would be reclassified as 

firearms. Multiple commenters stated 

that there were millions of firearms 

produced prior to 1968 that are not 

serialized and that requiring application 

of a serial number to these firearms 

would lower their value. 

Commenters estimated that 

approximately 300 million firearms 

would need to be serialized under the 

rule and that the time frame to serialize 

these firearms under the proposed rule 

would be unreasonably short. Other 

commenters estimated approximately 3 

million PMFs would need to be marked 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24717 

under the rule. For these PMFs, they 

estimated the costs for associated 

marking and transfer fees to be $180 

million dollars. 

Department Response 

ATF disagrees that the number of 

entities affected by the rule is the same 

or similar to the number of individuals 

who have commented on the proposed 

rule. The Small Business 

Administration considers small entities 

to be businesses, non-governmental 

organizations, or small governmental 

jurisdictions—not individuals. The 

estimated number of entities affected by 

the rule will be significantly smaller 

than the number of individuals who 

commented on the rule or who currently 

possess PMFs. Under the final rule, 

PMFs owned by individuals do not have 

to be serialized unless the PMF is 

transferred to an FFL and the FFL 

voluntarily accepts the PMF into 

inventory. At the time of the NPRM, 

ATF assumed that individuals who own 

PMFs would likely choose to avoid 

going through an FFL when disposing of 

their firearms to avoid serializing their 

PMFs. However, for the final rule, ATF 

outlines the individual populations and 

costs if individuals choose to take their 

PMFs to an FFL, and if that PMF is 

accepted into inventory. In addition, 

neither the NPRM nor this final rule 

define ‘‘privately made firearm’’ as 

including firearms manufactured or 

made prior to October 22, 1968, and this 

rule does not affect pre-October 22, 

1968, firearms that were not serialized 

unless remanufactured after that date. 

ATF did not account for the costs to 

entities that specialize in firearms 

customization for marksmanship 

competitions because the changes to the 

final rule’s definition of ‘‘frame or 

receiver’’ would not change the ability 

of these ‘‘micro-sale businesses’’ to 

customize firearms by replacing pistols 

slides and accessories. Under the final 

rule, these items would not be 

considered ‘‘frames or receivers.’’ 

Therefore, those businesses would not 

be required to be licensed as 

manufacturers if they customize 

firearms by replacing pistol slides and 

accessories for individual unlicensed 

customers. 

d. Definition of ‘‘Frame or Receiver’’ 

Comments Received 

Many commenters stated that having 

firearms with multiple serial numbers 

would be cost prohibitive. Some 

commenters suggested that, should 

manufacturers have to mark multiple 

serial numbers, retooling designs would 

cost a significant amount of money and 

investment. They also asserted 

manufactures would have to spend time 

and money to match up the firearm 

pieces into one firearm. Some 

commenters suggested that this would 

increase the cost of firearms for 

purchasers. Other commenters stated 

that the industry would need to change 

how it marks, sells, and advertises 

unfinished receivers that would be 

considered ‘‘firearms’’ under the final 

rule. 

Commenters stated that the new 

regulations requiring multiple parts to 

be serialized would harm both citizens 

and the firearms industry by limiting 

growth and innovation in the industry. 

One commenter stated that the industry 

would be forced to seek determinations 

from ATF because manufacturers would 

be unable to determine which part of 

the firearm is the frame or receiver. 

Other commenters stated that firearms 

manufacturers would be forced to mark 

multiple parts of a firearm because they 

might not have requested a 

determination or received a response to 

a determination request submitted to 

ATF. One commenter stated that 

restricting the parts of a firearm that a 

company can sell would cause a shift in 

supply and demand. 

One commenter asserted that the cost 

estimates did not align with how the 

manufacturing process works. The 

commenter claimed that, to comply 

with the rule, manufacturers would 

have to totally rework their 

manufacturing processes and 

recordkeeping systems. Another 

commenter stated that companies that 

produce raw forgings and castings 

would be required to become FFLs. The 

commenter claimed that this would 

increase the cost of these items or cause 

manufacturers to change their 

production to include machining of the 

raw materials. 

Some commenters suggested that it 

would cost more to purchase individual 

pieces because they would now have to 

go through FFLs to purchase their 

firearm kits and pay a transfer fee for 

each frame or receiver they purchase. 

One commenter asked if there would be 

enough FFLs to serialize firearms in the 

required time period, asked how 

individuals with disabilities or without 

transportation would visit an FFL to 

have their firearms serialized, and asked 

if individuals would be reimbursed for 

unserialized firearms seized by the 

government. 

Department Response 

Based on the public comments 

received, the final rule changes the 

proposed definition of firearm ‘‘frame or 

receiver’’ to identify only one part of a 

firearm that will need to be marked. 

However, if a company were to sell a 

firearm parts kit with a partially 

complete ‘‘frame or receiver,’’ or a 

multi-piece frame or receiver where 

there is more than one modular subpart, 

the frames or receivers of these items 

will now need to be serialized in 

accordance with this rule, increasing the 

cost of these items. 

ATF acknowledges that the proposed 

regulation would have posed some 

compliance issues for manufacturers 

and that some companies that were not 

FFLs would have needed to become 

FFLs under the proposed rule. ATF 

modified the rule to alleviate those 

concerns by expressly excluding raw 

materials, by further clarifying certain 

terms, and by allowing manufacturers to 

adopt existing marks of identification in 

several circumstances. Further, retailers 

were required under the NPRM—and 

are required under the final rule—to 

mark only unserialized firearms that 

they currently have in inventory and 

any PMFs they take into inventory after 

the implementation of the final rule. In 

this regard, licensees will continue to 

have 60 days until after the effective 

date of the final rule to serialize firearm 

parts kits with partially complete 

‘‘frames or receivers’’ that they currently 

have in inventory. 

ATF concurs that individuals will 

now need to visit an FFL to purchase 

those firearm parts kits with a partially 

complete ‘‘frame or receiver’’ that may 

readily be completed, like other 

firearms. However, because there will 

only be one frame or receiver per kit, 

there will be no additional transfer fees. 

e. Firearm Kits With ‘‘Partially 

Complete Frames or Receivers’’ 

Comments Received 

ATF received various comments 

regarding the methodology used for 

determining populations and costs for 

non-FFL manufacturers of partially 

complete frames or receivers and 

firearm kits. Several commenters treated 

the manufacturers and retailers of these 

items as one group and stated that the 

population estimated by ATF was too 

low. One commenter claimed that ATF 

misstated the number (36) of non-FFLs 

selling firearm parts kits with a partially 

complete ‘‘frame or receiver’’ because an 

internet search the commenter 

conducted on ‘‘80 lower’’ returned more 

than 75 websites selling these items. 

Many commenters asserted that ATF 

could not properly determine how 

much of an effect on commerce this rule 

will have for manufacturers. Some 

commenters stated that ATF did not 

account for non-FFL manufacturers 


jspears on DSK121TN23PROD with RULES2
24718 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

becoming licensed. Other commenters 

claimed that the new regulations would 

ruin non-FFL businesses that sell 

unregulated parts. One commenter 

opined that non-FFL manufacturers are 

not likely to become licensed and that, 

because most of these companies are 

small, this final rule will force these 

companies to go out of business. One 

commenter stated that ATF did not 

account for lost revenue and increased 

expenses for gunsmiths, companies 

producing firearm parts kits, and 

individuals. Some public commenters 

stated that non-FFLs would be unable to 

become licensed either due to the costs 

associated with becoming licensed or 

zoning restrictions, and that ATF did 

not account for companies going out of 

business. 

Commenters stated that ATF did not 

estimate the impact on revenue this rule 

will have on the public and that ATF’s 

assumptions were unsupported. One 

commenter stated that ATF made a 

flawed assumption that there would be 

no cost because non-FFL manufacturers 

would choose not to become licensed 

because of the ‘‘primary marketing 

scheme of some of these non-FFL 

manufacturers.’’ The commenter 

claimed that, even if only a few of these 

manufacturers choose to become 

licensed, the costs could be in the 

millions. Another commenter similarly 

stated that there was no analysis or 

evidence presented on non-FFLs 

choosing to become licensed or forgoing 

selling newly regulated items. One 

commenter stated that ATF failed to 

estimate the number of parts kits and 

PMFs and that it did not quantify the 

total costs for destroying or turning in 

such items. Additionally, the 

commenter stated that ATF failed to 

explain how it arrived at the conclusion 

that all non-FFL retailers would choose 

to destroy their inventory of unmarked 

parts kits and PMFs. 

One commenter stated that, according 

to the RIA, parts kits and some 

unfinished receivers currently available 

will no longer be sold. This commenter 

asked if the RIA assumed that nonlicensed manufacturers will produce 

kits with ‘‘unformed blocks of metal.’’ 

The commenter believed that sales of 

such kits would be lower than sales of 

existing kits because it would take more 

skill and additional tools to transform 

the new kits into frames or receivers. 

One commenter stated that ATF failed 

to provide an analysis of the exact 

amount of revenue per business that 

non-FFL retailers would lose if they 

chose to sell part kits without 

unfinished receivers. One commenter 

stated that the assumption in the RIA 

was that kits without a frame or receiver 

would not be regulated, but that the text 

of the proposed rule did not make this 

clear. 

A couple of commenters stated that 

ATF’s assumptions that 10 percent of 

Type 01 and Type 02 FFLs currently 

deal in firearm parts kits with a partially 

complete ‘‘frame or receiver’’ and that 

all dealers would have only two such 

items in inventory lacked any 

supporting evidence or data and cited 

only unknown subject matter experts. 

Several commenters suggested that 

the populations, cost assumptions, and 

descriptions for in-house engraving 

were inaccurate. One commenter stated 

that engraving equipment is not 

common at FFLs. One commenter 

suggested that the only viable means of 

engraving is with a laser engraver, 

associated equipment and safety 

supplies, and a specialized worker. 

Several commenters suggested the labor 

and equipment needed to engrave 

existing inventory is significantly higher 

than the stamping method discussed in 

the NPRM. Another commenter stated 

that the costs in the ATF’s analysis were 

underestimated and questioned how 

ATF came to the conclusions about the 

number of FFLs that have parts kits, 

who would mark the kits, how they 

would be marked, and why kits that do 

not need to be serialized would have an 

embedded metal plate on which to mark 

a serial number. The commenter also 

noted that ATF did not include the cost 

estimate for the 36 non-FFL dealers to 

have their parts kits marked by a 

licensee. One commenter stated that 

ATF’s estimate of a one-time cost for 

contracting out gunsmithing services in 

order to mark inventory that would 

need to be serialized was unsupported 

by evidence or data. 

Department Response 

ATF partially concurs that the 

population of affected dealers of firearm 

parts kits with partially complete frames 

or receivers was underestimated. In the 

NPRM, ATF found 71 companies selling 

such kits. Because the requirements for 

manufacturers and retailers are 

different, ATF accounts for them 

separately in different chapters of the 

RIA, which makes the numbers per 

chapter lower than the population 

estimates suggested by commenters. 

Although all 71 companies sell firearm 

parts kits with a partially complete 

frame or receiver, ATF broke up the 

number of companies between 

manufacturers and dealers of kits. After 

receiving comments, ATF performed a 

second internet search of companies 

and found an additional 58 companies, 

but broke up the total number of 

companies into four groups: FFL and 

non-FFL manufacturers, and FFL and 

non-FFL dealers. By categorizing the 

companies this way, the population 

numbers appear to be relatively low in 

each chapter of the RIA, but the overall 

number of companies affected is similar 

to the estimated total number of 

companies suggested by the commenter. 

For the final RIA, ATF revised the 

methodology and costs associated with 

this final rule to incorporate the costs 

that commenters suggested will arise. 

ATF concurs that lost revenue was not 

accounted for in the proposed rule, and 

the final rule now incorporates both the 

loss in revenue for companies and 

additional expenses for individuals. 

Under the final rule, firearm parts kits 

with partially complete frames or 

receivers will no longer be able to be 

sold without a serial number. The RIA 

revised the estimates to assume that 

firearm parts kits with partially 

complete frames or receivers will be 

regulated. As a result, ATF revised its 

estimates to reflect companies that 

could dissolve their businesses and 

provided a more precise estimate as to 

how much revenue non-FFL retailers 

would lose due to the requirements of 

the final rule. 

In response to commenters that stated 

ATF’s assumptions were lacking a 

detailed methodology or were otherwise 

unsupported, ATF reiterates that the 

agency does not maintain consolidated 

or aggregated records on companies’ 

inventory, regardless of whether the 

item in question is regulated, nor can 

ATF interview all manufacturers to 

determine their intended future actions 

upon publication of the final rule. 

Moreover, most of the items in 

companies’ inventories are not currently 

regulated. ATF has made reasonable 

estimates based on information 

provided by commenters, willing 

participants in informational surveys, 

and ATF subject matter experts. In the 

NPRM, ATF relied on subject matter 

experts from the Firearms Industry 

Programs Branch to provide an 

estimated population, i.e., the number 

of firearm parts kits with a partially 

complete frame or receiver in inventory. 

However, because such parts kits are not 

viewed by industry members as 

regulated, and because ATF does not 

have the inventory data that FFLs 

maintain, ATF is unable to obtain 

estimates at the level of accuracy 

requested by public commenters. 

However, to improve on these estimates 

for the final rule, ATF relied on general 

observations from its field divisions to 

estimate population and inventory. This 

was determined to be the best 

information available for the analysis. 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24719 

Next, ATF concurs with commenters 

that the costs associated with the inhouse engraving methods outlined in 

the NPRM were inaccurate, and ATF 

has changed its assumptions that 

considered only FFLs that currently 

have gunsmiths on staff. ATF estimates 

a one-time contracting cost for 

gunsmithing services to account for 

FFLs that have firearm parts kits with a 

partially complete frame or receiver 

currently in inventory but do not have 

gunsmithing capabilities. ATF made 

this assumption because, based on 

anecdotal commentary from various 

ATF field division offices, as well as 

comments on the NPRM, most FFLs do 

not have gunsmiths on staff; therefore, 

it is unlikely that they will purchase 

engraving equipment if the staff and 

equipment are not already part of their 

normal operations. It is not clear that 

only FFLs with gunsmithing capabilities 

will carry firearm parts kits with a 

partially complete frame or receiver; 

therefore, ATF assumed that a portion of 

the population will need to contract for 

gunsmithing services. 

As for purchasing a laser engraver, 

associated equipment and safety 

supplies, and labor, ATF used 

information about such costs to 

illustrate engraving expenses for 

manufacturers. ATF disagrees that a 

licensed dealer will need to purchase 

such equipment or hire more employees 

with the requisite engraving skills 

because future firearm parts kits with a 

partially complete frame or receiver will 

be serialized by a licensed manufacturer 

and not the licensed dealer. ATF 

concurs that it did not account for costs 

from serializing such parts kits made 

from polymer materials. In order to 

account for these costs, ATF has now 

included the costs for disposing of such 

items if they cannot be serialized. ATF 

also concurs that the cost for non-FFL 

dealers to serialize was omitted from the 

analysis and therefore has incorporated 

such costs into its revised RIA. 

f. Gunsmithing 

Comments Received 

ATF received numerous comments on 

gunsmiths. Commenters, including a 

licensed manufacturer that operates as a 

small business, stated the rule will have 

a major impact on the business by 

increasing the cost of gunsmithing 

services and recordkeeping 

requirements. The licensee claimed that 

the resulting decrease in profitability 

will affect the company’s ability to 

expand and asserted that the new 

regulations would complicate the 

process of performing a quick activity, 

such as bore sighting or adjustments, 

because the firearm must be recorded in 

the A&D records and the firearm must 

be marked with a serial number. This 

licensee also stated that many 

gunsmiths perform services that do not 

involve engraving and that these FFLs 

would need to expand their services or 

lose business. 

One commenter stated that persons 

should not have to be licensed to 

provide marking on firearms for 

nonlicensees because it is the 

responsibility of the FFL to ensure the 

firearm has been marked per regulation. 

The commenter also argued that 

licensing would increase costs without 

adding any benefits. Additionally, this 

commenter believed that ATF used the 

incorrect occupational code for salary 

and wages in the RIA and that the more 

precise code has a higher labor rate. One 

commenter described the significant 

burden and expense a gunsmith in 

training would endure to acquire the 

parts necessary to build 30 different 

firearms. The commenter explained that 

parts purchased online would need to 

be transferred through an FFL, which 

involves fees for completion of the Form 

4473, and a second trip to the FFL after 

the required 10-day waiting period in 

his location. 

One commenter asked for an 

explanation regarding the ‘‘one-time 

cost for contract gunsmithing estimated 

to be $180,849’’ and the $45,212 listed 

in chapter 4.3 of the RIA. This 

commenter asserted that ATF 

underestimated the number of A&D 

Record entries that gunsmiths would 

need to make and the cost of making 

these entries. The commenter argued 

that the hourly wage used for the 

calculation is out of date because the 

cost of labor has increased. One 

commenter suggested there was a 

discrepancy regarding contract 

gunsmithing. Another commenter 

worried that ATF significantly 

underestimated the activities for 

gunsmithing and did not understand 

why the number of items needing to be 

serialized was so low. One commenter 

did not agree with ATF’s assessment in 

chapter 4 of the RIA that ‘‘3,359 FFLs 

would outsource their firearms to 

another FFL for gunsmithing work.’’ 

Department Response 

ATF affirms that the current A&D 

Record requirements need to be 

maintained whenever firearms are 

acquired in inventory. The final rule 

clarifies that Type 01 and Type 02 FFLs 

that do gunsmithing work that includes 

marking services for nonlicensees are 

not required to apply for a Type 07 

manufacturer’s license. ATF reiterates 

that PMFs for personal use are not 

required by the GCA or this rule to be 

serialized (unless required by State or 

local law); instead, serialization is 

required only for those that are taken 

into inventory, which—as the final rule 

clarifies, based on ATF’s longstanding 

view—does not include same-day 

adjustments or repairs. Because repairs 

are performed by gunsmiths, ATF 

assumes that only FFLs that are 

gunsmiths or hire gunsmiths will be 

performing repairs or customizations of 

PMFs, so ATF incorporated the annual 

costs for these FFLs. 

As stated by various public 

commenters and reinforced by ATF 

subject matter experts, not all FFL 

dealers are capable of engraving; 

therefore, there may be FFLs that 

outsource their existing inventory of 

firearm parts kits with a partially 

complete frame or receiver to another 

FFL or a non-FFL that has engraving 

services available under the FFL’s direct 

supervision. Existing PMFs currently in 

inventory are not required to be marked 

under the FFL’s direct supervision so 

long as the marking occurs within 60 

days from the effective date of the rule, 

or prior to final disposition, whichever 

is sooner. As for the affected 

populations, because such parts kits are 

not currently viewed by their 

manufacturers or members of the public 

as regulated, ATF is not able to 

definitively determine the number of 

affected items that would need to be 

serialized with the specificity that 

commenters requested. 

g. Silencers 

Comments Received 

One commenter stated that ATF 

underestimated the cost to serialize all 

parts of a silencer while another 

commenter stated that the benefits of 

adding additional serialized parts of a 

silencer do not outweigh the costs. One 

commenter asked if ATF would pay for 

replacement of parts. One commenter 

believed that multiple parts of a silencer 

would be classified as the frame or 

receiver; the commenter also claimed 

that every silencer manufacture would 

need to request a variance and that ATF 

did not include the cost of processing 

the variances. One commenter asked if 

ATF would be covering the cost of a 

silencer part if it is damaged while the 

serial number is being marked. 

Additionally, the commenter wanted to 

know who would pay to have the 

silencer parts marked if all parts need to 

be marked. 

Department Response 

In both the proposed and final rule, 

ATF required or requires only that the 


jspears on DSK121TN23PROD with RULES2
24720 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

140Under this rule, the frame or receiver of a 

muffler or silencer is the part that provides housing 

or a structure for the primary internal component 

designed to reduce the sound of a projectile. 

Typically, this is the largest external part, or outer 

tube, without which the device would have no 

structure to hold the primary internal sound 

reduction component(s) and that is marked with a 

serial number, registered in the NFRTR, and for 

which excise tax must be paid. ATF has long taken 

the position that the creation of the outer tube 

results in the making of a new silencer, see 26 

U.S.C. 5845(i) (definition of ‘‘make’’), and the fact 

that a tube is used to replace a damaged outer tube 

is of no consequence because a functional device 

cannot be made without it. For this reason, the new 

regulatory text expressly excludes muffler or 

silencer frames or receivers from being transferred 

for replacement purposes without marking, 

recording, and registering them in accordance with 

27 CFR parts 478 and 479. 

‘‘frame’’ or ‘‘receiver’’ of a firearm 

muffler or silencer device be marked, 

and the final rule makes clear which 

part is the frame or receiver of a 

modular silencer. Additionally, the final 

rule makes clear that the end cap of a 

silencer or a sound suppressor cannot 

be a ‘‘frame’’ or ‘‘receiver.’’ Based on 

public comments received in the 

ANPRM for silencers and mufflers, see 

81 FR at 26764, the final rule will not 

significantly change the way the 

industry currently marks silencers. In 

most cases, the ‘‘frame’’ or ‘‘receiver’’ 

would be the outer tube. 

Under Federal law, 26 U.S.C. 5842(a), 

and 27 CFR 479.102, each person 

manufacturing or making each 

‘‘firearm’’—including a ‘‘muffler or 

silencer,’’ see 26 U.S.C. 5845(a)—is 

required to mark the ‘‘firearm’’ in 

accordance with the regulations and 

register it in the NFRTR. This rule as 

proposed and finalized eliminates the 

substantial cost of marking each and 

every individual internal part defined as 

a muffler or silencer, as well as the end 

cap of an outer tube. Additionally, 

under this rule, individual internal 

muffler or silencer parts may be 

transferred by NFA-qualified 

manufacturers to other qualified 

licensees for further manufacture or 

repair of complete devices without 

immediate registration or payment of 

NFA transfer tax, and complete devices 

that are registered may be temporarily 

conveyed for replacement of these 

internal parts. However, the term 

‘‘repair’’ does not include replacement 

of the outer tube. The outer tube is the 

largest single part of the silencer, the 

main structural component of the 

silencer, and the part to which all other 

component parts are attached. ATF has, 

therefore, taken the position that the 

replacement of the outer tube is so 

significant an event that it amounts to 

the ‘‘making’’ of a new silencer. Hence, 

the new silencer must be marked, 

registered, and transferred after payment 

of transfer tax in accordance with the 

NFA and GCA.140 By law, this transfer 

tax is owed by the transferor, not the 

government. See 26 U.S.C. 5811(b). 

h. Markings on ‘‘Privately Made 

Firearms’’ 

Comments Received 

One commenter worried that 

requiring firearms made from parts kits 

to be marked would destroy their value 

as collector’s items. One commenter 

stated that the loss of tax revenue due 

to acquisition of marking equipment 

was not calculated in the costs 

described in ATF’s RIA. Many 

commenters feared that FFLs would lose 

business because they do not have 

engraving machines and cannot work on 

PMFs. Several commenters stated that 

the cost of serializing a PMF ranges 

between $35 and $405 based on whether 

the services include serializing alone or 

related services such as cleaning, oiling, 

bluing, polishing, or refinishing the 

firearm. One commenter stated that the 

per-individual costs in the RIA were 

underestimated because individuals 

tend to own more than one firearm and 

that the per individual cost should 

include several handguns and at least 

one rifle. Another commenter claimed 

that the assumption that individuals 

will not be charged for serialization is 

inaccurate. 

One commenter stated that the type of 

‘‘low cost, hand-embossing tools’’ used 

for estimates of marking costs were not 

appropriate for marking steel or 

aluminum frames or receivers because 

the depth requirement may not be met, 

making the markings less durable. Many 

commenters asserted that a laser 

engraving machine would be needed to 

meet the marking requirements. One 

commenter stated that these machines 

cost at least $10,000 and that this type 

of machine is not available at most 

firearms retail stores. Many commenters 

were concerned that the estimated 

engraving cost of $25 is too low and 

suggested that the actual cost of 

engraving is between $45 and $65. One 

commenter was also skeptical of the low 

number of PMFs that ATF stated were 

in dealers’ inventories because the 

agency provided no evidence as to how 

this number was determined. 

One commenter stated that the rule 

would ‘‘reduce consumer value’’ by 

reducing the number of available parts 

kits because it would hurt hobbyists 

who enjoy building their own firearms 

and take away the privacy of owning an 

unmarked firearm. One commenter 

stated that not all FFLs have the 

equipment to mark firearms and that 

Type 07 manufacturers that do have the 

equipment may not want to mark PMFs. 

This commenter did not believe there 

are enough FFLs with the proper 

equipment for the number of firearms 

that will need to be marked. One 

commenter stated that chapter 6 of the 

RIA did not address the costs associated 

with recordkeeping for PMFs. 

Department Response 

ATF disagrees that it needed to 

calculate the loss of tax revenue due to 

acquiring serializing equipment. 

Estimating tax revenue is beyond the 

scope of the rule and is speculative, 

especially since companies are not 

required to purchase equipment, much 

less become FFLs. ATF also disagrees 

that it did not properly estimate the 

total number of PMFs affected by the 

rule or that it underestimated the 

number of firearms affected per 

individual. Neither the proposed nor 

final rule requires the serialization of all 

PMFs in circulation. This aspect of the 

rule affects only firearm parts kits with 

a partially complete frame or receiver 

held by FFLs and PMFs that are 

transferred through an FFL; therefore, 

ATF account for only kits and PMFs 

held by FFLs or that may go through 

FFLs. However, in the final analysis, 

ATF provides an estimate of the total 

number of PMFs in circulation, along 

with potential costs to individuals who 

go through an FFL for services 

associated with marking their PMFs. 

FFLs are not required to acquire 

equipment to serialize firearms. Should 

they choose to receive a PMF from a 

non-FFL, the FFL could either require 

the individual to serialize the PMF prior 

to acceptance or directly oversee the 

engraving by another FFL or even a nonFFL. PMFs that may have been accepted 

into inventory prior to the effective date 

of this rule may also be outsourced for 

marking to a licensed manufacturer or 

gunsmith within the 60-day grace 

period. ATF revised the estimated costs 

to assume those with existing 

gunsmithing capabilities will perform 

engraving services in-house. FFLs 

without marking capabilities will either 

dispose of their inventory, outsource the 

inventory to another FFL that has 

marking capabilities, or directly oversee 

the engraving by a non-FFL. 

Furthermore, in the NPRM, ATF 

assumed that individuals with PMFs 

would not choose to undertake repairs 

or customization of their PMFs so as to 

avoid marking requirements; therefore, 

it did not anticipate those costs to 

individuals. Based on gunsmithing 

experience from subject matter experts 

from the Firearms Ammunition 

Technology Division, most individuals 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24721 

141OMB, Circular A–4 at 2 (Sept. 17, 2003), 

available at https://www.whitehouse.gov/wpcontent/uploads/legacy_drupal_files/omb/circulars/ 

A4/a-4.pdf (last visited Mar. 23, 2022). 

seeking repairs or customization 

typically do not seek bluing or other 

services at the same time they are 

seeking engraving services. ATF concurs 

that the analysis in the NPRM regarding 

engraving was inaccurate. ATF agrees 

that a more likely scenario is that there 

may be some FFLs that sell firearm parts 

kits with a partially complete frame or 

receiver that also offer gunsmithing 

services. These FFLs will not need to 

purchase embossing equipment; rather, 

they can use their existing staff and 

equipment to serialize their existing 

inventory of kits. For FFLs that do not 

employ gunsmiths or have existing 

gunsmithing equipment, ATF estimates 

that these FFLs will contract out 

engraving services to another FFL, 

supervise the engraving services from a 

non-FFL, or dispose of their inventory. 

In order to simplify costs, ATF 

estimated only serialization from FFLs 

and not non-FFLs being supervised by 

the contracting FFL. 

ATF concurs with commenters that 

there would be an additional cost for 

hobbyists and has updated the 

economic analysis accordingly. ATF 

revisited its estimate of the cost to have 

multiple serial numbers on a firearm 

because, under the final rule, the 

definitions identify only one frame or 

receiver per firearm and therefore the 

vast majority of firearms will only have 

one serial number per firearm. Because 

only one regulated part will be defined 

as a ‘‘frame or receiver,’’ ATF 

anticipates the cost would not be 

prohibitive for hobbyists. 

Although FFLs are regulated, ATF 

does not have any records or data 

reflecting the number of weapon or 

frame or receiver kits with a partially 

complete frame or receiver that FFLs 

may have in their inventories. 

Furthermore, the Paperwork Reduction 

Act prevents ATF from surveying more 

than nine companies for information 

without going through the formal 

procedures to collect information from 

the public. See 44 U.S.C. 3502(3)(A)(i). 

As stated above, ATF revised the 

methodology to ascertain the number of 

FFLs affected and the number of firearm 

parts kit with a partially complete frame 

or receiver by relying on information 

from ATF’s field divisions to estimate 

this population, which was determined 

to be the best available information 

available for the analysis. 

i. Records Retention 

1. Population 

Comments Received 

ATF received various comments 

regarding the population affected by the 

cost of record retention. Some 

commenters stated that the cost of 

shipping all firearm records to ATF was 

not accounted for or that ATF’s 

estimated shipping cost was too low to 

account for shipments from all FFLs. 

Another commenter suggested that, 

regardless of whether an FFL ships 

records to ATF voluntarily, all FFLs 

should be accounted for, not only the 

ones that currently destroy their records 

that are over 20 years old. One 

commenter stated that ATF should have 

done an advanced notice of proposed 

rulemaking to find out the number of 

FFLs that retain their records for more 

than 20 years instead of relying on 

subject matter expert estimates. The 

commenter also believed that ATF’s 

estimate that less than 10 percent (or 

5,407) of dealers and collectors are not 

retaining their records beyond 20 years 

is too low because the RIA lists the 

number of FFLs at 113,204, and 10 

percent of this number is 11,320, which 

is twice what is listed in the RIA. 

Department Response 

The Department disagrees with 

commenters who said the agency 

underestimated the cost per FFL and 

that it should have taken into account 

the costs borne by all FFLs. Federal law, 

see 18 U.S.C. 923(g)(4); 27 CFR 478.127, 

already requires FFLs to send all of their 

out-of-business records to ATF. ATF 

does not consider these costs as 

attributable to the rule because the duty 

to send out-of-business records to ATF 

is an existing statutory and regulatory 

requirement. In the NPRM, ATF 

estimated that most FFLs currently store 

records beyond 20 years and will not be 

affected by the indefinite records 

retention requirement. As described 

below, the cost burden for extending the 

record retention requirement will affect 

only a subset of the total number of 

FFLs. Furthermore, the Office of 

Management and Budget (‘‘OMB’’) 

explains that the baseline for measuring 

a rule’s costs should be ‘‘what the world 

will be like if the proposed rule is not 

adopted.’’ 141 Prior to the publication of 

the NPRM, the majority of FFLs 

maintained records until 

discontinuance of business or licensed 

activity regardless of whether they 

remained in business for 20 years or not. 

Because any alternative, including the 

proposed rule, would be a comparison 

against this baseline, only the 

incremental cost above this baseline is 

attributed to this rule. 

The 113,204 total number of FFLs is 

for all types of FFLs at the time of the 

analysis. Records retention affects a 

subset of all FFLs, in particular, Type 01 

and Type 02 FFLs, because licensed 

manufacturers (Types 06, 07, and 10) 

and importers (Types 08 and 11) 

generally maintain permanent 

consolidated production, acquisition, 

and disposition records in accordance 

with 27 CFR 478.129(d) and ATF 

Rulings 2011–1 and 2016–3. 

Additionally, ATF estimates that 

licensed collectors (Type 03) generally 

maintain their curio or relic collection 

records until discontinuance of licensed 

activity. At the time of the NPRM, there 

were only 60,079 Type 01 and 02 FFLs, 

and of those, fewer than 10 percent were 

estimated to be destroying their records 

that were more than 20 years old. In the 

RIA for the final rule, ATF reiterates 

that records retention primarily affects 

Types 01 and 02 FFLs, and thus not all 

FFLs are listed in the overview of the 

analysis. 

2. Costs 

Comments Received 

Various commenters suggested that 

the new reporting requirements alone 

should have made the rule economically 

significant. Commenters suggested that 

ATF did not account for the influx of 

transactions records for multiple 

‘‘frames’’ or ‘‘receivers’’ or the influx of 

transaction records from purchases of 

firearm parts kit with a partially 

complete ‘‘frame or receiver’’ that would 

be disposed of as a ‘‘firearm’’ under the 

rule. Similarly, one commenter 

suggested ATF should use NICS checks 

and population growth models to 

account for the increased number of 

transactions and number of records in 

the future. 

One commenter suggested that, in 

2018, nine million firearms were 

manufactured. Accounting only for nine 

million firearms, the cost burden per 

record was estimated to be $0.02 per 

record. One commenter argued that the 

NPRM’s cost estimate of $68,939 does 

not realistically encompass the 

recordkeeping requirements for all 

79,869 FFLs because the number of 

records retained and therefore 

submitted will grow over time. This 

commenter further suggested that, based 

on the NPRM estimate of $68,939 for the 

entire industry, the per shipment cost 

for all records over 20 years would be 

$0.86 per FFL, which the commenter 

asserted was too low. Other commenters 

stated that the RIA estimated only 

additional storage costs for ATF but not 

the costs to FFLs. 


jspears on DSK121TN23PROD with RULES2
24722 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

Several commenters suggested that 

the NPRM did not account for the 

increase in the number of records FFLs 

will have to maintain due to the 

increased number of transactions likely 

to happen if a firearm has multiple 

serial numbers. One estimated that the 

recordkeeping burden for ATF Forms 

4473 would increase by 437 million. 

One commenter stated FFLs that have 

voluntarily retained records beyond 20 

years will have a greater cost of storing 

records indefinitely than FFLs that 

destroyed or surrendered records older 

than 20 years because the FFLs that 

retained their records will overall have 

more records that will need to be stored. 

This commenter believed that the rule 

change will encourage FFLs to destroy 

records beyond 20 years prior to the 

change, which will hurt ATF’s ability to 

trace firearms. 

One commenter estimated that it 

would cost the firearms industry $8.1 

billion to develop and secure electronic 

records and that it would cost ATF $546 

million annually to maintain and 

support electronic storage of records. 

Several commenters suggested that the 

low records retention cost described in 

the RIA was due to an over-reliance on 

savings from converting paper records 

to electronic storage. One commenter 

suggested that the cost for electronic 

storage should include a team of 

employees to create and maintain 

electronic storage for the FFL. 

One commenter suggested that ATF 

relied too heavily on subject matter 

experts for assumptions used in the RIA 

and noted that the experts’ 

methodologies were unknown to the 

public. Furthermore, this commenter 

questioned the assumption that all FFLs 

would send their records older than 20 

years to ATF. One commenter suggested 

that ATF consider an alternative to this 

requirement with a time frame between 

20 years and indefinite. 

Department Response 

The Department did not account for 

the potential increase in the number of 

records stored due to an increase in 

transactions recorded for multiple 

‘‘frames’’ or ‘‘receivers;’’ however, this 

cost no longer needs to be accounted for 

as a result of changes to the definition 

of firearm frame or receiver. 

Nonetheless, the Department concurs 

that there will be an increase in firearms 

records because there could be more 

firearms transactions; this could 

increase the overall record retention 

cost. There were 14 million NICS checks 

in 2010 and almost 40 million NICS 

checks in 2021. In the cost section of 

chapter 7 of the RIA, ATF forecasts the 

estimated increase in Form 4473 

applications based on the number of 

reported NICS checks and NFA 

applications by year and estimates the 

increase in shipping costs for FFLs to 

send their records to ATF when their 

business or licensed activity is 

discontinued. 

Under the initial RIA, the $68,939 

cost to retain records beyond the 

existing 20-year requirement was not 

distributed among the total 113,204 

FFLs. ATF subject matter experts report 

that most FFLs already retain records 

indefinitely beyond the existing 20-year 

requirement until discontinuance of 

business or licensed activity. For most 

FFLs, this practice is already an 

industry standard and thus the cost of 

this practice is not attributable to this 

rule. Therefore, as stated in the NPRM 

and the final rule, not all FFLs will 

incur recordkeeping costs as a result of 

this rule’s implementation. However, 

ATF agrees that there may be some FFLs 

that do not maintain records 

indefinitely or that transfer their records 

to a successor FFL. These FFLs may 

now incur additional recordkeeping 

costs to comply with this rule. Costs 

were estimated for these FFLs and ATF 

has revised the final analysis. 

Because FFLs are required by 18 

U.S.C. 923(g)(4) and 27 CFR 478.127 to 

send all of their records to ATF upon 

absolute discontinuance of their 

business or licensed activity, ATF does 

not consider costs for FFLs to ship their 

records to ATF upon such a 

discontinuance to be a cost of this rule; 

instead, it is a cost of the existing 

requirement in 18 U.S.C. 923(g)(4) and 

27 CFR 478.127. ATF did not receive 

comments that would otherwise 

contradict the recordkeeping analysis; 

therefore, the NPRM cost analysis 

remains the same. 

Most FFLs have and will continue to 

retain records, and this rule will not 

affect these FFLs. As stated above, most 

FFLs retain records for more than 20 

years. This existing activity pre-dates 

the final rule, and costs of this activity 

thus are not attributable to the rule. 

However, the small number of FFLs that 

currently destroy records older than 20 

years could incur some costs. For 

purposes of the final RIA, ATF estimates 

that, in an effort to reduce their costs, 

these FFLs may utilize electronic 

storage. Furthermore, most FFLs that 

use electronic formats of A&D records or 

electronic Forms 4473 outsource these 

software applications to a third party 

rather than hiring staff and building the 

program in-house; therefore, ATF is not 

incorporating the cost for an FFL to 

create and maintain electronic storage of 

their records. 

ATF uses subject matter experts as the 

best available information when it lacks 

data because there is no requirement to 

regulate or track certain activities or 

items. However, ATF was able to use 

trace data and out-of-business records as 

a proxy to estimate the number of FFLs 

that do not retain records older than 20 

years and that therefore could be 

affected by this rule. For this final rule, 

ATF determined this to be the best 

available information. Also, in its final 

analysis, ATF revised the costs for FFLs 

that currently voluntarily ship records 

older than 20 years. Upon promulgation 

of this rule, these FFLs will no longer 

be able to ship their records to ATF that 

are older than 20 years without 

discontinuing business or licensed 

activity. However, shipping out-ofbusiness records remains an option 

should these FFLs choose to 

discontinue their current licensed 

business or activity and apply for a new 

license for a business that maintains an 

electronic recordkeeping system so that 

they may dispose of their paper records 

to ATF. 

3. Benefits 

Comments Received 

Some commenters stated that ATF did 

not quantify or monetize benefits for the 

record retention requirement. One 

commenter suggested that the benefits 

do not outweigh the costs. One 

commenter asserted that ATF did not 

demonstrate how many crimes would be 

solved through tracing firearms over 20 

years old. Some commenters believed 

that, with records older than 20 years, 

ATF would be unable to identify the 

most recent owner of the firearm 

because too much time would have 

passed, and this would lead to increased 

failures in tracing. One commenter 

believed ATF failed to meet the 

requirements of the APA because it did 

not explain how electronic records 

would lower the cost of storing records, 

nor did ATF explain why it did not 

include this information. 

Department Response 

Tracing a firearm that was involved in 

a criminal activity is an existing 

requirement and not a new requirement 

attributable to this rule. Based on the 

amount of records previously received 

by the NTC, ATF anticipates the cost 

burden for this requirement will be 

small. Commenters are incorrect in their 

assumption that the rule would lead to 

an increased rate of failed traces because 

the records are too old. To the contrary, 

being able to trace a firearm to the first 

unlicensed transferee of the firearm 

from a firearms licensee, no matter how 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24723 

long ago, provides useful investigative 

leads to law enforcement. Furthermore, 

this final rule now includes, in Section 

IV.B.5.d of this preamble, information 

on the number of traces submitted over 

the past 12 years that could not be 

successfully completed because the 

licensee informed ATF it did not have 

the record for that firearm because the 

record was more than 20 years old and 

had been destroyed. 

ATF disagrees with respect to putting 

forth additional analysis regarding 

electronic storage. The option for 

electronic storage is an existing option 

and this rule only expressly codifies and 

expands that option for licensees in an 

alternate method approved by the 

Director. See ATF Rul. 2016–1; ATF 

Rul. 2016–2. Specifically, it is 

anticipated that the option for 

maintaining electronic storage of ATF 

Forms 4473 will be updated via an ATF 

Ruling issued contemporaneously with 

this final rule. 

j. Form Updates 

Comments Received 

Commenters asserted that the cost to 

update software for electronic 

recordkeeping was understated. Some 

commenters feared that it would cost a 

significant amount of money to update 

existing software to track multiple serial 

numbers because current systems allow 

for only a single serial number. Other 

commenters stated that some FFLs 

would need to acquire new software 

systems because the existing systems 

may no longer be supported by the 

original developer to make updates. 

Some commenters suggested that ATF 

did not account for extra time needed to 

enter multiple serial numbers into 

records. 

Department Response 

ATF concurs that, based on public 

comments, it would likely cost a 

significant amount of money to revamp 

software programs to account for 

multiple serial numbers. For this and 

other reasons, ATF has revised the 

definition of ‘‘frame or receiver’’ so that 

it describes a single part of a weapon as 

the frame or receiver, meaning that 

generally only one serial number would 

need to be recorded per firearm in the 

same manner as under current 

regulations. The rare exceptions would 

be if a manufacturer or importer chooses 

not to adopt an existing serial number 

on a firearm that is remanufactured or 

imported, or if a multi-piece frame or 

receiver had been assembled from 

modular subparts with different serial 

numbers marked on the same frame or 

receiver. Therefore, no cost was 

attributed to this requirement. 

k. Government Costs 

Comments Received 

Many commenters stated that the 

government would incur additional 

costs associated with lawsuits filed 

against the rule. Some commenters 

worried that States will lose sales and 

tax revenue because companies will go 

out of business. Other commenters 

expressed concern that the government 

would spend more money arresting and 

incarcerating law-abiding people who 

they believed would become criminals 

under this rule. One commenter stated 

that the rule would lead to increased 

cost to the government because the 

government would need additional 

personnel, equipment, and training to 

enforce the rule. 

Department Response 

The Department did not account for 

the cost of lawsuits because costs due to 

potential lawsuits would be speculative. 

Although ATF estimated there could be 

a number of businesses that go out of 

business, there is no guarantee of 

accuracy in the number of businesses 

that would go out of business due to 

implementation of the rule; therefore, 

ATF deemed it too speculative to 

estimate a loss in tax revenue. 

Furthermore, ATF is not spending more 

money to arrest people who make and 

possess PMFs as a result of this rule. As 

stated earlier, nothing in this rule 

prevents unlicensed law-abiding 

citizens and hobbyists from making 

their own firearms by using 

commercially produced parts or by 

using 3D printers; or from transferring 

PMFs to others as long as they are not 

engaged in a business or activity 

requiring a license. If such persons wish 

to engage in the business of 

manufacturing, importing, or dealing in 

firearms, they must obtain a license like 

any other manufacturer, importer, or 

dealer. 

l. Lack of Benefits 

Comments Received 

Many commenters claimed that the 

assertion that PMFs are used in crimes 

is not supported by the BJS survey on 

how criminals acquire firearms 

(referenced earlier in Section IV.B.8 of 

this preamble), and that the rule’s 

asserted benefits are not supported by 

the FBI’s Uniform Crime Statistics. 

Many commenters stated that firearms 

are used in a small percentage of crimes. 

They claimed that the number of 

firearms recovered at crime scenes is 

low and not all perpetrators are arrested 

and convicted. One commenter stated 

that the RIA failed to show why the lack 

of serial numbers is important to 

criminals and did not consider other 

methods that the criminal may use 

(removing a serial number or using a 

different type of weapon) to circumvent 

the new requirements. Another 

commenter asserted that there is no 

evidence that PMFs are the weapon of 

choice for criminals. 

Many commenters argued that ATF 

did not show how the proposed rule 

would reduce crime. Some commenters 

stated the NPRM did not indicate the 

number of traces that identified the 

perpetrator, resulted in an arrest, or 

substantially affected the prosecution of 

the criminal. Nor did it provide the 

percentage of unserialized firearms used 

in crimes or show how many crimes 

could be solved if PMFs could be traced. 

A commenter asserted that, if the data 

is available, the public should be able to 

comment on it. Another commenter 

pointed to studies that suggest that 

firearms restrictions do not have an 

impact on gun violence. One commenter 

argued that the tracing of serialized 

firearms has failed to reduce deaths 

caused by these weapons. 

Another commenter stated that the 

majority of firearms traces are for 

weapon offenses, not violent crimes 

such as homicides, assaults, or 

robberies. ‘‘Mere weapon offenses,’’ 

according to the commenter, ‘‘cause no 

immediate harm,’’ and ‘‘thus the vast 

majority of traces do not involve the 

remediation of many violent uses of 

guns.’’ The commenter also argued that 

the ‘‘costs of failing to obtain a 

conviction on a weapon offense [are] 

minuscule,’’ especially because ‘‘the 

perpetrator will likely be convicted of 

some other associated crime.’’ This 

commenter also stated that ATF failed 

to show how an increase in traces 

would lead to increased arrests and 

convictions and that ATF did not 

provide a monetary benefit of this 

supposed increase. Because only a small 

number of firearms required to be 

marked under this rule will ever be 

traced, according to the commenter, the 

‘‘external costs’’ of failed tracing are low 

and do not support the burden of the 

rulemaking. Another commenter argued 

that homicides committed with PMFs 

would be a very small portion of cases 

that would be addressed by this rule, 

while another commenter claimed that 

it would take 30 years of homicides 

committed with PMFs to equal one year 

of homicides committed with serialized 

firearms. 

One commenter stated that, although 

ATF reported the number of traces that 

include suspected PMFs and the 


jspears on DSK121TN23PROD with RULES2
24724 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

number of homicides related to the 

usage of PMFs, ATF did not attempt to 

monetize these deaths and injuries. 

Another commenter stated that ATF 

failed to show the value or benefits, 

either individually or on the whole, of 

regulating firearms kits with a partially 

complete frame or receiver or 

unassembled frames and receivers and 

related parts kits. One commenter stated 

that ATF failed to explain why it cannot 

monetize or quantify the purported 

benefit of consistent marking 

requirements. The commenter stated 

that the agency failed to explain who 

benefits and how large the benefits are, 

thus not meeting its burden under the 

APA. The commenter argued that ATF 

could have provided the benefit of 

easing marking requirements without 

adding additional marking 

requirements. 

One commenter stated that there is no 

need for regulation because PMF owners 

can voluntarily mark their firearms. If 

they choose not to, the commenter said, 

it is because they do not find a benefit 

in it and only hurt themselves if the 

firearm is lost or stolen. The commenter 

also stated that ATF failed to provide 

information on the number of lost or 

stolen PMFs or parts kits and the 

number of these firearms or kits that 

could not be returned to the legal owner 

due to the lack of a serial number. 

Additionally, the commenter said ATF 

failed to show how often criminals 

receive PMFs using a straw purchaser. 

Another commenter argued that the rule 

will not deter straw purchasers. 

Department Response 

The Uniform Crime Statistics 

referenced by commenters are compiled 

through the FBI’s Uniform Crime 

Reporting (‘‘UCR’’) Program. The UCR 

Program, however, does not collect 

crime information on PMFs. As a result, 

ATF did not rely upon UCR Program 

data to explain the rise in suspected 

PMFs that are recovered and traced from 

crime scenes. FBI Uniform Crime 

Statistics were not considered pertinent 

for present purposes and were not used 

in analyzing the costs and benefits of 

this rule. 

Furthermore, based on tracing and 

National Integrated Ballistics 

Information Network data, many law 

enforcement agencies may not be 

reporting PMFs accurately, and 

therefore, ATF believes that the number 

of PMFs reported as being used in 

crimes is significantly smaller than the 

actual number. Aware of these potential 

reporting errors, the number of PMFs 

ATF has presented in the RIAs 

accompanying the NPRM and this final 

rule is likely to be much lower than the 

actual number recovered. ATF did, 

however, provide more quantifiable 

benefits in the final RIA based on an 

increased ability to trace all firearms, 

and particularly, PMFs. ATF reiterates 

that the primary benefit of the final rule 

is promoting public safety and 

restricting felons and other prohibited 

persons’ access to firearms. 

m. Proposed Alternatives 

Comments Received 

Thousands of commenters claimed 

that ATF did not mention any one of the 

regulatory alternatives proposed by the 

wider firearms industry that several 

commenters believe were raised with 

ATF during an early 2021 meeting 

reported by the Wall Street Journal. See 

Zusha Elinson, Ghost-Gun Concerns 

Prompt Feds to Meet With Firearms 

Makers, Wall St. J. (Mar. 26, 2021), 

available at https://www.wsj.com/ 

articles/ghost-gun-concerns-promptfeds-to-meet-with-firearms-makers11616756403 (last visited Mar. 23, 

2022). Other commenters asserted that 

ATF failed to adequately consider or 

explain why it was not considering the 

regulatory alternatives provided in the 

NPRM. For example, one industry 

member stated that, of its four 

regulatory alternatives, ATF did not 

explain regulatory alternative number 

one, which was no change, and 

regulatory alternative number three, 

which was to grandfather all existing 

firearms. For instance, the commenter 

stated that ATF did not explain for 

alternative number three why it would 

be difficult to bring enforcement actions 

against the continued manufacturing of 

noncompliant receivers or explain why 

the burden of doing so would not be 

justified by the alleged fact that there 

are ‘‘no costs’’ associated with the third 

option’s implementation. 

Numerous commenters opposed to 

the NPRM stated that ATF should 

grandfather in all personally owned 

items to preserve citizens’ civil liberties 

and to avoid criminal entrapment. Some 

commenters suggested that ATF allow 

non-FFLs to continue selling unfinished 

lower receivers while placing the 

burden on the consumer to register the 

firearm with an FFL once the consumer 

completes the process of privately 

manufacturing a lower receiver. The 

commenter argued that it is illogical to 

require manufacturers and retailers of 

unfinished lower receivers to adhere to 

a regulatory system that is a ‘‘veiled 

scheme of forced compliance against 

gun owners.’’ In the commenter’s 

opinion, only when an unfinished lower 

receiver is finished by the end user can 

the final owner be identified and the 

markings be completed and known (e.g., 

gauge or caliber). 

One commenter suggested that ATF 

consider non-regulatory alternatives 

such as corrective taxes and subsidies, 

aid from non-governmental 

organizations, tort law, public service 

advocacy, and private contracting. 

Another commenter suggested that ATF 

consider other alternatives, such as 

requiring that records be retained for 

longer than 20 years (but less than 

indefinitely) or allowing anyone to mark 

weapons. 

Department Response 

The Department disagrees with 

commenters who stated that ATF did 

not consider regulatory alternatives 

proposed by the wider firearms industry 

during an early 2021 meeting reported 

by the Wall Street Journal because ATF 

was not presented with any regulatory 

alternatives other than keeping the 

current limited and outdated 

definitions. 

The ‘‘no change’’ alternative has no 

costs or benefits because it would 

involve maintaining the status quo. This 

alternative was considered but not 

implemented because the GCA requires 

that all firearms be regulated. Currently, 

the vast majority of firearms fall outside 

the scope of the existing regulatory 

definition of ‘‘frame or receiver.’’ Due to 

recent court rulings, it would be 

difficult for the Department to continue 

to successfully prosecute criminal 

activity relying on the existing 

regulatory definition of ‘‘frame or 

receiver’’ because that definition does 

not capture the vast majority of firearm 

designs. 

With respect to grandfathering all 

existing firearms, the proposed rule 

sought to allow manufacturers and 

importers to mark firearms of the same 

design and configuration in the same 

manner as before the effective date of 

the final rule. The final rule makes clear 

that almost all firearms ATF previously 

classified as falling within the definition 

of ‘‘frame or receiver’’ prior to issuance 

of the final rule are grandfathered and 

may continue to be marked in the same 

manner as before the effective date of 

the final rule. The only exceptions are 

certain ATF classifications of partially 

complete, disassembled, or 

nonfunctional frames or receivers 

because, at the time of classification of 

those articles, ATF may not have been 

provided with, or did not examine, a 

full and complete parts kit containing 

those items along with any associated 

templates, jigs, molds, equipment, tools, 

instructions, guides, or marketing 

materials that were made available by 

the seller or distributor of the item or kit 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24725 

to the purchaser or recipient of the item 

or kit. As explained in this final rule, 

these items and materials are necessary 

for ATF and others to make a proper 

firearm classification under the GCA 

and NFA (if applicable). 

To clarify, existing firearm parts kits 

with a partially complete frame or 

receiver, and PMFs owned by or 

serviced by FFLs that were determined 

not to be ‘‘frames or receivers’’ as 

defined prior to this rule, will not be 

grandfathered in, meaning that FFLs 

may be required to mark these firearms 

in accordance with the new regulations 

if the FFLs wish to maintain them in 

their inventories. This rule does not 

require unlicensed PMF owners to do 

anything to their firearms maintained 

solely for personal use. 

ATF has determined that the ‘‘nonregulatory alternative’’ of imposing a 

higher tax on firearms that are currently 

being regulated would only make the 

cost of regulated firearms more 

expensive to the public and would not 

affect the PMFs or firearm parts kits that 

currently fall outside of the regulatory 

regime. Subjecting firearms to higher 

taxes would not ensure that all firearms, 

whether commercially or privately 

made, are treated the same under the 

regulations when they enter interstate 

commerce. This in turn would not 

achieve ATF’s objectives of ensuring 

that felons and prohibited persons are 

not able to obtain firearms and that 

firearms can be traced. The objective of 

this rule is not to make firearms more 

expensive or more difficult for the 

public to obtain; rather, the objectives of 

the rule are to ensure that all firearms, 

as defined by the GCA, are regulated 

similarly; to remove the current 

regulatory definitions of ‘‘frame or 

receiver’’ and replace them with 

definitions that capture the vast 

majority of firearm designs and 

advancements in firearms technology; to 

allow law enforcement to trace firearms, 

including PMFs; and to prevent felons 

and other prohibited persons from 

easily acquiring firearms. It is not clear 

how implementing corrective taxes 

would prevent criminals from obtaining 

firearms or help law enforcement 

officers solve crimes. 

It is not clear how the commenter’s 

suggested alternative scenarios using 

non-regulatory alternatives (e.g., tort or 

public advocacy) would be carried out. 

However, these alternatives are out of 

ATF’s purview and beyond the scope of 

this regulation; therefore, these 

alternatives were not considered. 

Although the alternative of requiring 

record retention for longer than 20 

years, but less than indefinitely, was 

considered, ATF determined that this 

alternative was not the best course of 

action. Because firearms are durable 

items that can be in circulation for many 

decades or even beyond 100 years, an 

alternative specifying a specific time 

frame for record retention requirements 

would not align with the shelf life of 

most firearms. Thus, without the 

indefinite retention requirement 

imposed by this rule, ATF would 

continue to encounter the problem of 

not being able to successfully trace older 

firearms that are used in the 

commission of a crime. As a result, ATF 

does not believe such alternatives 

would achieve the intended benefits of 

this final rule. 

n. Final Regulatory Flexibility Analysis 

Comments Received 

Many commenters asserted that the 

rule will have a significant impact on 

small businesses. Other commenters 

argued that a robust small business 

analysis was not performed. Some 

commenters stated that the rule will 

have a negative impact on many small 

businesses, including those owned by 

veterans and families. They further 

stated the rule would impact businesses 

that sell firearms parts as well as those 

that specialize in firearms 

customization. 

A major distributor of firearms parts 

pointed out that ATF failed to explain 

how there can be a significant financial 

impact on individual businesses but not 

all the businesses in the same industry. 

One commenter listed multiple reasons 

the Initial Regulatory Flexibility Act 

(‘‘IRFA’’) was, in the commenter’s 

opinion, not done according to law. The 

reasons included a lack of a statement 

of objectives and legal basis for the 

proposed rule; a lack of evidence that 

the 132,023 affected entities would 

experience minimal or no cost; a failure 

to accurately estimate the affected 

population of non-FFL retailers; a lack 

of sufficient analysis on the impact on 

non-FFL retailers; and a failure to 

provide sufficient analysis of the impact 

on the unfinished lower receiver 

market. The commenter stated that there 

was no analysis addressing the cost of 

becoming licensed or providing options 

that would have the same result as 

regulation. Additionally, the commenter 

believed the market for unfinished 

receivers would be quickly diminished. 

One commenter stated that the IFRA 

analysis contained errors, such as ATF’s 

failure to monetize or quantify benefits 

or explain why it did not do so and 

ATF’s dismissal or underestimation of 

costs. 

One commenter asserted that the rule 

has ‘‘net negative benefits’’ so it should 

not move forward. The commenter 

believed that the change in record 

retention requirements would result in 

fewer successful firearm traces because 

of the increased number of documents 

retained. Several commenters stated that 

ATF failed to provide the actual number 

of small businesses that would be 

affected and the estimated costs that the 

affected entities would incur. 

Some commenters stated that 

manufacturers of unfinished receivers 

and firearm parts kits with an 

unfinished frame or receiver would 

choose not to obtain an FFL and instead 

go out of business. This would hurt 

firearms manufacturers because they 

purchase these items as part of their 

production process. Several commenters 

suggested that this rule will result in 

significant job losses in manufacturing. 

One commenter stated that this rule 

would affect his ability to expand his 

business and another commenter stated 

that it had put off business expansion 

and new hiring because of the rule. 

Another commenter stated that, because 

of the anticipated increase in the price 

of unfinished receivers as a result of the 

rule, he would no longer be able to 

provide classes in firearms safety, 

maintenance, and marksmanship. 

One commenter stated that the real 

cost of the proposed rule is not the lost 

revenue of the affected companies but 

the loss in the value of these companies, 

which hurts the companies’ owners. 

The commenter also stated that ATF 

failed to show the anticipated number of 

jobs lost and the value associated with 

the loss. 

Many commenters asserted that ATF 

underestimated the cost to the industry. 

One commenter stated that small 

businesses would need to acquire 

engraving equipment and inventory 

tracking systems. Those businesses that 

could not afford this expense, according 

to the commenter, would be forced to 

destroy inventory. One commenter 

stated that both large and small entities 

would need to spend time and money 

to ensure compliance with the new 

regulations. One commenter argued that 

ATF did not consider the true cost to 

non-manufacturing FFLs for equipment 

purchases and training, and for the 

volume of PMFs needing serialization to 

recoup the return on the investment. 

Department Response 

ATF agrees that different entities will 

experience a range of costs as outlined 

by the different chapters of the RIA, and 

ATF revised the regulatory flexibility 

analysis to describe the largest impact 

on small businesses, which is that some 

businesses will no longer continue 


jspears on DSK121TN23PROD with RULES2
24726 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

operations. The IRFA has been updated 

to reflect these costs. 

ATF concurs that large and small 

entities may require time to research 

and understand regulations. However, 

this is already an existing cost of 

regulations in this industry in general 

and is not a new requirement specific to 

this rule. Therefore, it is not considered 

a cost of this rule. In accordance with 

the Small Business Regulatory 

Enforcement Fairness Act (‘‘SBREFA’’), 

a small business compliance guide will 

be published because this final rule will 

impact a significant number of small 

businesses. 

o. APA Requirements 

Comments Received 

One commenter suggested that this 

rule should be considered both a 

regulatory and economically significant 

rule because of its impact on a 

substantial number of small businesses, 

as indicated in the RIA. Another 

commenter believed that the rule 

violated Executive Order 12866. 

Department Response 

As stated in the NPRM, this rule is a 

‘‘significant regulatory action’’ under 

section 3(f)(4) of Executive Order 12866; 

however, this rule is not ‘‘economically 

significant,’’ as that term is defined in 

the Executive Order. An ‘‘economically 

significant’’ rule is one estimated to cost 

$100 million or more in one given year. 

This rule is not expected to reach that 

threshold. As discussed in the Final 

Regulatory Flexibility Analysis 

(‘‘FRFA’’), ATF agrees that this rule 

could potentially affect small businesses 

that only manufacture or deal in firearm 

kits with a partially complete frame or 

receiver, but notes that whether a rule 

has significant impacts on small 

businesses does not determine if the 

rule is economically significant under 

Executive Order 12866. Nevertheless, 

because this rule has the potential to 

significantly affect small businesses, 

ATF has performed an IRFA and a 

FRFA. 

p. Congressional Review Act 

Comments Received 

One commenter disagreed with the 

Department’s claim in the NPRM that 

this rulemaking is not a ‘‘major rule,’’ 

which is defined in 5 U.S.C. 804(2), in 

part, as a rule that ‘‘resulted in or is 

likely to result in . . . an annual effect 

on the economy of $100,000,000 or 

more’’ or; ‘‘significant adverse effects on 

. . . innovation.’’ 

Department Response 

ATF disagrees that this this is a 

‘‘major rule’’ as defined under 5 U.S.C. 

804(2). This rule is estimated to cost less 

than $100 million in any given year, as 

outlined in the standalone RIA. Further, 

the Department disagrees this rule 

stifles or impacts innovation. To the 

contrary, the regulations are being 

updated to accommodate changes in 

firearms technology and terminology, 

and the industry may develop new 

innovations to comply with the updated 

regulations. 

q. Unfunded Mandate 

One commenter believed that the rule 

would exceed the one-year allowable 

threshold of $177 million (adjusted for 

inflation since 1995) set by the 

Unfunded Mandates Reform Act. See 2 

U.S.C. 658c. 

Department Response 

ATF disagrees that the rule will be a 

major rule under the Unfunded 

Mandates Reform Act. The rule is 

estimated to cost less than $100 million 

in any given year, as outlined in the 

standalone RIA. 

14. Other Concerns With the Rule 

a. Comment Process 

Comments Received 

At least one commenter claimed that 

there were concerns in online groups 

and boards that a number of comments 

meeting the guidelines for being 

publicly posted were ‘‘subsequently 

deleted,’’ thus ‘‘forcing people to issue 

new comments for the rule,’’ or that 

comments were moderated prior to 

publishing, raising a free speech 

concern. The commenter stated that, 

although these comments might have 

contained offensive language or have 

included threats, or may have been 

similar to other comments indicating 

spam, those comments should still have 

been considered as either supporting or 

opposing the proposed rule. Another 

commenter stated that the agency’s 

instructions that commenters selfidentify and provide contact 

information ‘‘severely limit the degree 

and amount of public participation.’’ 

They also argued that these instructions 

chilled speech protected by the First 

Amendment and discouraged members 

of the public from commenting. Because 

of this, the commenter stated that ATF 

should re-open the comment period. 

Department Response 

ATF received just over 290,000 

comments during the 90-day comment 

period. The vast majority of comments 

were received through the online 

Federal portal (www.regulations.gov) 

with the balance coming through mail 

and fax. The NPRM’s Public 

Participation section informed the 

public that there may be a significant 

delay between the time a person 

submits a comment through one of the 

three methods before it becomes visible 

online due to the volume of comments 

received on any given day. The Federal 

Docket Management System (‘‘FDMS’’), 

the portal through which Federal 

agencies manage their rulemaking 

dockets, requires the agency to review 

comments before making them visible to 

the public on regulations.gov. With the 

exception of a limited ability to redact, 

FDMS does not allow agency users of 

the system to alter or change the 

substance of a comment. ATF posted 

and reviewed comments, even 

numerous duplicate comments (i.e., 

comments from the same submitter with 

the same content) that were generally 

consistent with the posting guidelines, 

i.e., comments that did not contain 

excessive profanity or contain 

inappropriate or sensitive content. No 

comments were deleted or removed, 

unless upon request of a submitter. 

The Department disagrees that ATF’s 

instructions that commenters selfidentify ‘‘severely limit the degree and 

amount of public participation,’’ chill 

speech, or discourage the public from 

commenting, as evidenced by the 

volume of comments received on the 

NPRM, as well as the content of some 

comments that expressly declared that 

they will not comply with any 

regulation. ATF has historically 

requested persons to self-identify and 

include contact information largely in 

the event that a person makes a 

comment that the agency would like to 

follow up on to gain further information 

or perspective from the commenter. 

There were recent updates to the online 

Federal portal that allowed the public to 

submit comments under an 

‘‘Anonymous’’ feature; ATF accepted, 

posted, and considered these comments. 

Accordingly, the Department disagrees 

that ATF should re-open the comment 

period. 

b. No Federalism Impact Statement 

Comments Received 

At least one commenter asserted that 

ATF should have prepared a federalism 

summary for the NPRM pursuant to 

Executive Order 13132, entitled 

‘‘Federalism.’’ This Executive Order is a 

directive meant to ‘‘guarantee the 

division of governmental 

responsibilities between the national 

government and the States’’ and 

‘‘further the policies of the Unfunded 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24727 

142 64 FR 43225 (Aug. 10, 1999). 

143 ‘‘Policies that have federalism implications’’ 

are defined as ‘‘regulations . . . that have 

substantial direct effects on States, on the 

relationship between the national government and 

the States, or on the distribution of power and 

responsibilities among the various levels of 

government.’’ E.O. 13132, sec. 1(a). 

144See 18 U.S.C. 922(b)(2) (making it unlawful for 

a licensee to sell or deliver any firearm to any 

person in any State where the purchase or 

possession by such person would violate any State 

law or published ordinance); 18 U.S.C. 923(d)(1)(F) 

(requiring license applicants to certify compliance 

with State and local law). 

145See footnotes 24, 35, and 121, supra; see also 

86 FR at 27730 n.62. However, State and local 

jurisdictions are not entitled to redefine, amend, or 

exempt persons from the provisions of Federal law. 

Mandates Reform Act.’’ 142 Under 

Section 6 of the Executive Order, 

agencies are not permitted, to the extent 

practicable and permitted by law, to 

issue any regulation that has 

‘‘federalism implications’’ 143 if the 

regulation imposes substantial direct 

compliance costs on State and local 

governments and is not required by 

statute, or if the regulation preempts 

State laws, unless the agency consults 

with State and local officials and 

prepares a federalism impact summary. 

The commenter argued that, although 

the NPRM acknowledged that States 

have chosen different policymaking 

paths to regulate or not regulate PMFs 

or kits, the Department and ATF failed 

to engage in a federalism analysis of its 

‘‘constitutional and statutory authority 

for [its] action’’ in accordance with 

section 3(b) of the Executive Order. That 

section requires such analysis and 

consultation with State or local officials 

if the agency’s action limits the 

policymaking discretion of the States 

and if ‘‘there are significant 

uncertainties as to whether national 

action is authorized or appropriate.’’ 

The commenter further argued that, 

pursuant to section 4(a) of the Executive 

Order, the NPRM failed to acknowledge 

that the Federal re-definition of 

‘‘firearm’’ and mandated marking 

requirements would preempt State laws, 

such as State laws on the storage and 

transportation of firearms and on the 

marking or registration of PMFs. Finally, 

the commenter observed that State laws 

often rely on Federal classifications. For 

all these reasons, according to the 

commenter, States might be directly 

affected by the NPRM. 

Department Response 

The Department disagrees that a 

federalism impact statement is needed 

for this rulemaking under Executive 

Order 13132. This rule, which 

implements the GCA, does not preempt 

State laws or impose a substantive 

compliance cost on States. Under the 

GCA, 18 U.S.C. 927, State and local 

jurisdictions may enact their own 

requirements and restrictions on 

firearms unless there is a direct and 

positive conflict such that the two 

cannot be reconciled or consistently 

stand together. State and local 

jurisdictions are therefore free to create 

their own definitions of terms such as 

‘‘firearm’’ and ‘‘frame or receiver’’ to be 

applied for purposes of State or local 

law within their respective 

jurisdictions. They are free to mandate 

their own requirements concerning the 

marking, storage, sale, and 

transportation of firearms.144 This rule 

points out that numerous State and local 

jurisdictions have, in fact, enacted their 

own restrictions on unmarked, 

unserialized, 3D-printed, or 

undetectable firearms, and firearms with 

obliterated, removed, or altered serial 

numbers, and have adopted 

requirements to report or record the 

serial number marked on pawned 

firearms.145 This rule as proposed and 

finalized does not purport to impose 

any costs upon or otherwise limit the 

authority of State and local 

governments. To the contrary, the GCA 

and NFA implementing regulations at 

27 CFR 478.58 and 479.52, which are 

not being amended, expressly state that 

holders of Federal firearms licenses and 

NFA taxpayers are not conferred any 

right or privilege to conduct business or 

activity contrary to State or other law, 

and that they are not immune from 

punishment for conducting a firearm or 

ammunition business or activity in 

violation of State or other law. 

V. Final Rule 

A. Definition of ‘‘Firearm’’ 

The rule finalizes, with minor 

changes, the amendments proposed in 

the NPRM to the definition of ‘‘firearm’’ 

in part 478, which clarify that this term 

includes a weapon parts kit that is 

designed to or may readily be 

completed, assembled, restored, or 

otherwise converted to expel a projectile 

by the action of an explosive. 

B. Definition of ‘‘Frame or Receiver’’ 

The final rule accepts the 

recommendations of numerous 

commenters and provides a new 

definition to remove and replace the 

terms ‘‘firearm frame or receiver’’ and 

‘‘frame or receiver’’ in §§ 478.11 and 

479.11 (referencing § 478.12). The new 

definition, set forth in a new § 478.12, 

separately defines ‘‘frame’’ for 

handguns, and ‘‘receiver’’ for rifles, 

shotguns, and other weapons that expel 

a projectile other than handguns. Rather 

than a definition that describes any 

housing for any fire control component, 

these definitions now describe only a 

single housing or structural component 

for one specific fire control component 

of a given weapon including ‘‘variants 

thereof,’’ a term that is also defined. For 

handguns, or variants thereof, it is the 

housing or structure for the primary 

energized component designed to hold 

back the hammer, striker, bolt, or 

similar component prior to initiation of 

the firing sequence (i.e., sear or 

equivalent), even if pins or other 

attachments are required to connect 

such component to the housing or 

structure. For rifles, shotguns, and 

projectile weapons other than 

handguns, or variants thereof, it is the 

housing or structure for the primary 

component designed to block or seal the 

breech prior to initiation of the firing 

sequence (i.e., bolt, breechblock, or 

equivalent), even if pins or other 

attachments are required to connect 

such component to the housing or 

structure. 

The final rule amends the definitional 

supplement to ‘‘frame or receiver’’ 

entitled ‘‘firearm muffler or silencer 

frame or receiver’’ to define a single 

component of a complete firearm 

muffler or silencer device as the frame 

or receiver, and clarifies how the 

definition applies to a modular device 

with more than one housing or structure 

for the primary internal sound reduction 

components. Specifically, the terms 

‘‘frame’’ and ‘‘receiver’’ mean the 

housing or structure for the primary 

internal component designed to reduce 

the sound of a projectile (i.e., baffles, 

baffling material, expansion chamber, or 

equivalent) (formerly, ‘‘essential 

internal components’’). Additionally, 

the terms ‘‘frame’’ and ‘‘receiver’’ now 

exclude ‘‘a removable end cap of an 

outer tube or modular piece.’’ 

The final rule does not adopt the 

definitional supplement of ‘‘split or 

modular frame or receiver,’’ though a 

definition was added to define the term 

‘‘multi-piece frame or receiver’’ and text 

was added to explain how and when 

such a frame or receiver must be 

marked. In this regard, the rebuttable 

presumption in the definition of ‘‘frame 

or receiver’’ was amended in the final 

rule to explain that the marked 

subpart(s) of a multi-piece frame or 

receiver must be presumed to be part of 

the frame or receiver of a weapon or 

device absent an ATF classification or 

other reliable evidence to the contrary. 

The final rule amends the supplement 

to the proposed definition of ‘‘frame or 

receiver’’ entitled ‘‘partially complete, 

disassembled, or inoperable frame or 

receiver’’ by: (1) Replacing the term 


jspears on DSK121TN23PROD with RULES2
24728 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

‘‘inoperable’’ with the more accurate 

term ‘‘nonfunctional’’; (2) clarifying that 

this supplement also addresses frame or 

receiver parts kits; (3) explaining what 

it means for a frame or receiver to 

function as a frame or receiver; 

(4) removing the definition ‘‘partially 

complete,’’ and, instead, expressly 

excluding from the definition of ‘‘frame 

or receiver’’ forgings, castings, printings, 

extrusions, unmachined bodies, or 

similar articles that have not yet reached 

a stage of manufacture where they are 

clearly identifiable as an unfinished 

component part of a weapon (e.g., 

unformed blocks of metal, liquid 

polymers, and other raw materials); (5) 

clarifying the items that the Director 

may consider when classifying a 

partially complete, disassembled, or 

nonfunctional frame or receiver; and (6) 

providing detailed examples of what 

would and would not be a ‘‘frame or 

receiver’’ that may readily be 

completed, assembled, restored, or 

otherwise ‘‘converted’’ to a functional 

state. 

The final rule makes minor changes to 

the proposed supplement to the 

definition of ‘‘frame or receiver’’ 

entitled ‘‘destroyed frame or receiver.’’ 

For example, the final rule removes 

examples of specific ATF approved 

methods of destruction in the regulatory 

text in favor of general terminology. 

Additionally, the final rule clarifies that 

the term ‘‘frame or receiver’’ includes 

the specific component of a complete 

weapon or complete firearm muffler or 

silencer device, including variants 

thereof, determined (classified) by the 

Director to be defined as a firearm 

‘‘frame or receiver’’ prior to publication 

of the final rule, except for 

determinations concluding that a 

partially complete, disassembled, or 

nonfunctional frame or receiver 

(including a weapon or frame or 

receiver parts kit) was not, or did not 

include, a firearm ‘‘frame or receiver’’ as 

previously defined. This ‘‘grandfather’’ 

provision also includes nonexclusive 

examples and diagrams of previously 

classified weapons. 

C. Definition of ‘‘Readily’’ 

The final rule makes minor changes to 

the proposed definition of ‘‘readily’’ in 

Parts 478 and 479 to make clear that it 

applies to any process, action, or 

physical state, and that the listed factors 

are only relevant to firearm 

classifications. 

D. Definitions of ‘‘Complete Weapon’’ 

and ‘‘Complete Muffler or Silencer 

Device’’ 

The final rule makes minor 

amendments to the proposed definitions 

of ‘‘complete weapon’’ and ‘‘complete 

muffler or silencer device’’ in Parts 478 

and 479 by deleting ‘‘as designed’’ as it 

modified the phrase ‘‘necessary to 

function.’’ This change was necessary to 

ensure that firearms are not designed to 

avoid marking time limits by 

eliminating a nonessential component 

in the manufacturing process. 

E. Definition of ‘‘Privately Made 

Firearm’’ 

The final rule makes minor changes to 

the proposed definition of ‘‘privately 

made firearm’’ in part 478 to make it 

consistent with the changes to the 

definitions of ‘‘frame or receiver’’ and 

‘‘importer’s or manufacturer’s serial 

number,’’ and for clarity regarding the 

exclusion for pre-October 22, 1968 

manufactured firearms. 

F. Definition of ‘‘Importer’s or 

Manufacturer’s Serial Number’’ 

The final rule modifies the proposed 

definition of ‘‘Importer’s or 

manufacturer’s serial number’’ in part 

478. The term means the serial number 

placed by a licensee on a firearm, 

including any full or abbreviated license 

number, any such identification on a 

privately made firearm, or a serial 

number issued by the Director. It also 

specifies that for purposes of 18 U.S.C. 

922(k) and § 478.34, the term shall 

include any associated licensee name, 

or licensee city or State placed on a 

firearm. These changes ensure that these 

markings are considered a part of the 

‘‘importer’s or manufacturer’s serial 

number’’ because a firearm is difficult to 

trace without this information. 

G. Definition of ‘‘Gunsmith’’ 

This rule finalizes with clarifying 

changes the proposed definition of 

‘‘engaged in the business’’ as it applies 

to a ‘‘gunsmith’’ in part 478. Most 

significantly, the final rule makes clear 

that licensed dealer-gunsmiths are not 

required to be licensed as manufacturers 

if they only perform gunsmithing 

services on existing firearms for their 

customers, or for another licensee’s 

customers, because the work is not 

being performed to create firearms for 

sale or distribution. These services may 

include customizing a customer’s 

complete weapon by changing its 

appearance through painting, 

camouflaging, or engraving, applying 

protective coatings, or by replacing the 

original barrel, stock, or trigger 

mechanism with drop-in replacement 

parts. 

Licensed dealer-gunsmiths may also 

purchase complete weapons, make 

repairs (e.g., by replacing worn or 

broken parts), and resell them without 

being licensed as manufacturers. 

Likewise, under the final rule, licensed 

dealer-gunsmiths may make such 

repairs for other licensees who plan to 

resell them without being licensed as a 

manufacturer. They may also place 

marks of identification on PMFs they 

may purchase and sell, or under the 

direct supervision of another licensee in 

accordance with this rule. Persons 

performing these activities are 

distinguished from persons who engage 

in the business of completing or 

assembling parts or parts kits, applying 

coatings, or otherwise producing new or 

remanufactured firearms (frames or 

receivers or complete weapons) for sale 

or distribution. Such persons must be 

licensed as manufacturers. 

H. Marking Requirements for Firearms 

The final rule makes a number of 

amendments to the proposed marking 

requirements in parts 478 and 479. In 

addition to minor changes to conform 

the marking requirements to the new 

definition of ‘‘frame or receiver’’ that 

describes a single component, the final 

rule amends the text to explain how and 

by when multi-piece frames or receivers 

are to be identified, and that an 

identified modular subpart thereof may 

only be removed and replaced under 

certain limited conditions. With regard 

to the size and depth of markings, a 

minor change was made to clarify that 

only the serial number and associated 

license number need be marked in a 

print size no smaller than 1⁄16 inch. In 

the section addressing the meaning of 

marking terms, the final rule also 

defines the term ‘‘identify’’ to mean 

placement of identifying markings, 

clarifies that the term ‘‘legibly’’ means 

that the unique identification number 

within a serial number may include 

non-numeric characters, and also 

clarifies that the term ‘‘conspicuous’’ 

means that the markings must be 

capable of being easily seen with the 

naked eye. 

As to the time period for 

manufacturers to identify the firearms 

they produce, the term ‘‘from 

completion of the active manufacturing 

process’’ was not adopted in favor of the 

clearer statement ‘‘the entire 

manufacturing process has ended.’’ The 

exclusion from the time period for 

firearms ‘‘actively awaiting materials’’ 

was replaced with a rebuttable 

presumption that firearms awaiting 

materials, parts, or equipment repair to 

be completed are presumed, absent 

reliable evidence to the contrary, to be 

in the manufacturing process. Also, the 

time limits to mark firearms 

differentiate in the final rule between 

non-NFA complete weapons and frames 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24729 

146ATF Rulings are different from private letter 

firearms classifications. ATF issues formal public 

rulings (as distinguished from ‘‘private letter 

firearm classifications’’ to individual industry 

members) to promote uniform understanding and 

application of the laws and regulations it 

administers. ATF Rulings apply the law and 

regulations to a specific set of facts, and apply 

retroactively unless otherwise indicated, whereas 

private letter firearm classifications are in response 

to a private inquiry for a determination regarding 

a specific item or parts kit by ATF. Rulings do not 

have the force and effect of ATF regulations, but 

may be cited and relied upon as precedents in the 

disposition of similar cases. See 27 CFR 70.701(d) 

(as in effect on January 23, 2003, and continued by 

28 CFR 0.133(a)(2), (3)). 

147See 27 CFR 478.11 and 479.11 (‘‘Words in the 

plural form shall include the singular, and vice 

versa . . . .’’); FFL Newsletter, May 2012, at 5 (‘‘If 

a firearm is marked with two manufacturer’s names, 

or multiple manufacturer and importer names, FFLs 

should record each manufacturers’ and importers’ 

[sic] name in the A&D record.’’). 

or receivers disposed of separately, 

which must be marked within seven 

days after completion of the 

manufacturing process, and NFA 

firearms and parts defined as firearms, 

which must be marked by close of the 

next business day. This provides a 

reasonable grace period in which to 

mark firearms manufactured and makes 

them consistent with their respective 

recordkeeping requirements under the 

GCA and NFA. The final rule does not 

adopt the proposed seven-day 

alternative for manufacturers to record 

acquisitions of non-NFA firearms if 

commercial records are maintained, as it 

was not necessary in light of the sevenday grace period to mark non-NFA 

weapons. NFA weapons and parts must 

be marked and recorded by close of the 

next business day after manufacture. 

Furthermore, the final rule does not 

adopt the provision allowing licensees 

to obtain a variance for the period of 

time in which to mark their firearms 

because the grace periods being codified 

in the final rule are reasonable and well 

known to the industry. 

The final rule makes minor 

conforming amendments to the 

proposed requirement to mark PMFs. 

Additionally, unlike the proposed rule, 

the final rule allows licensed or 

unlicensed engravers to mark firearms 

on licensees’ behalf (with the requesting 

licensee’s information) provided: (1) 

The identification takes place under the 

direct supervision of the requesting 

licensee without the engraver taking the 

firearm into inventory; and (2) the 

markings otherwise meet the 

identification requirements. Also, the 

final rule text incorporates guidance 

from the NPRM’s preamble that an 

acceptable method of identifying a PMF 

is by placing the serial number on a 

metal serial number plate permanently 

embedded into a polymer frame or 

receiver, or other method approved by 

the Director. 

With regard to the marking 

exceptions, the final rule expands the 

rules allowing licensees to adopt (and 

not mark) the serial number or other 

identifying markings under certain 

conditions. Specifically, in light of 

comments received, the final rule allows 

licensed manufacturers to adopt (and 

not mark) the serial number and other 

markings previously placed on a firearm 

that has not been sold, shipped, or 

otherwise disposed of to a person other 

than a licensee (i.e., newly 

manufactured firearms). This change 

would supersede ATF Ruling 2009–5, 

which requires ATF to be notified when 

marks are adopted as an alternative to 

marking. The final rule also provides 

more specificity than the proposed rule 

on how licensees who remanufacture or 

import firearms may adopt (and not 

mark) the markings on firearms that 

were sold, shipped, or disposed of to a 

nonlicensee. The final rule allows 

licensed manufacturers to adopt the 

serial number and other identifying 

markings previously placed on a firearm 

by another licensee provided the 

manufacturer is performing services as a 

gunsmith (as defined in § 478.11) on 

existing firearms that are not for sale or 

distribution by a licensee. Further, the 

final rule allows licensees to adopt the 

unique identification number placed on 

a PMF by its unlicensed maker so long 

as the number is not duplicated on 

another firearm of the licensee, the 

number otherwise meets the 

identification requirements, and the 

licensee adds their abbreviated FFL 

number as a prefix to the existing 

identification number so that the 

firearm can be traced to the licensee 

who identified the firearm. 

The final rule also differs from the 

proposed rule in that it does not require 

firearm muffler or silencer parts that are 

transferred for further manufacture or 

repair to be ‘‘actively’’ in the 

manufacturing or repair process if those 

parts are being transferred for those 

purposes. In this regard, the definition 

of ‘‘transfer’’ in part 479 has been 

finalized as proposed to exclude 

temporary conveyances solely for repair, 

identification, evaluation, research, 

testing, or calibration. 

The final rule retains the marking 

grandfathering provision, but revises the 

text to remove ‘‘and configuration’’ and 

defines ‘‘new design’’ to explain when 

a frame or receiver is eligible for this 

exception. Notably, the more limited 

final definition of ‘‘new design’’ only 

applies to changes in the design of the 

existing frame or receiver to the extent 

it has been functionally modified or 

altered, as distinguished from 

performing a cosmetic process that adds 

to or changes the decoration of the 

frame or receiver (e.g., painting or 

engraving), or by adding or replacing 

stocks, barrels, or accessories to the 

frame or receiver. 

With respect to the voluntary process 

for seeking an ATF classification of 

firearms, the final rule clarifies that a 

firearm sample submitted to ATF must 

include all accessories and attachments 

relevant to such classification, and that 

each request for classification of a 

partially complete, disassembled, or 

nonfunctional item or kit must contain 

any associated templates, jigs, molds, 

equipment, or tools that are made 

available by the seller or distributor of 

the item or kit to the purchaser or 

recipient of the item or kit, and any 

instructions, guides, or marketing 

materials if they will be made available 

by the seller or distributor with the item 

or kit. Further, submissions of armor 

piercing ammunition with a projectile 

or projectile core constructed entirely 

from one or a combination of tungsten 

steel alloys, steel, iron, brass, bronze, 

beryllium copper, or depleted uranium 

must include a list of known handguns 

in which the ammunition may be used. 

These changes will help to ensure that 

ATF can make a proper classification of 

firearms and armor piercing 

ammunition. The final rule also clarifies 

that ATF classifications of a specific 

component as a frame or receiver, as 

distinguished from other firearms 

determinations, may be considered 

applicable to or authoritative with 

respect to other firearms produced by 

the requestor that are similar so that a 

separate classification does not need to 

be submitted to know which portion of 

a similar weapon to mark.146

I. Recordkeeping 

Because firearms would not have 

more than one frame or receiver, the 

final rule does not finalize the proposed 

changes to Parts 447, 478, and 479 to 

refer to in the plural form the 

manufacturer or importer name, country 

of manufacture, or serial number in 

required records. However, in the 

unlikely event there is more than one 

manufacturer or importer, country of 

manufacture, or serial number marked 

on a firearm, licensees must still record 

more than one name, country, or serial 

number in accordance with the existing 

regulatory requirements.147 In addition, 

the final rule substitutes ‘‘transaction 

number’’ for ‘‘serial number’’ in part 478 

with respect to the manner in which 

ATF Forms 4473 must be maintained to 

avoid confusion with the ‘‘importer’s or 

manufacturer’s serial number’’ placed 


jspears on DSK121TN23PROD with RULES2
24730 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

148See 27 CFR 70.701(d)(2) (as in effect on 

January 23, 2003, and continued by 28 CFR 

0.133(a)(2), (3)); Rulings, ATF (Oct. 20, 2021), 

available at https://www.atf.gov/rules-andregulations/rulings. 

149The term ‘‘amplified’’ is used to describe a 

situation where no change is being made in a prior 

published position, but the prior position is being 

extended to apply to a variation of the fact situation 

set forth in the new ruling. Thus, if an earlier ruling 

held that a principle applied to (A), and the new 

ruling holds that the same principle also applies to 

(B), the earlier ruling is amplified. See Rulings, ATF 

(Oct. 20, 2021), available at https://www.atf.gov/ 

rules-and-regulations/rulings. 

150The term ‘‘clarified’’ is used to describe a 

situation where the language in a prior ruling is 

being made clear because the language has caused, 

or may cause, some confusion. It is not used where 

a position in a prior ruling is being changed. See 

Rulings, ATF (Oct. 20, 2021), available at https:// 

www.atf.gov/rules-and-regulations/rulings. 

on a firearm. Further, the proposed 

recordkeeping requirement in part 478 

to record a ‘‘serial number’’ is amended 

to clarify that any license number either 

as a prefix, or if remanufactured or 

imported, separated by a semicolon, 

must be recorded in the serial number 

column for accurate tracing. The final 

rule also amends the proposed 

recordkeeping requirement for 

manufacturers in part 478 to make clear 

that production and acquisition records 

for non-NFA firearms manufactured or 

otherwise acquired must be recorded 

within seven days, not by close of the 

next business day as stated in the 

proposed rule, though NFA firearms 

must be recorded by close of the next 

business day unless there is a sufficient 

commercial record of acquisition, in 

which case the grace period to record 

would be extended until the seventh 

day. 

With regard to the licensee’s 

acquisition of PMFs into inventory, the 

final rule clarifies in part 478 that the 

serial number need not be immediately 

recorded if the firearm is being 

identified by the licensee, or marked 

under the licensee’s direct supervision, 

in accordance with § 478.92(a)(2). Once 

marked, the acquisition entry must be 

updated. Further, unlike the proposed 

rule, the final rule expressly allows 

licensed dealer-gunsmiths, 

manufacturers, and importers to 

conduct same-day adjustments or 

repairs of unmarked PMFs without 

marking them so long as they do not 

accept them into inventory overnight 

and they are returned to the person from 

whom they were received. If, however, 

the licensee has possession of the 

firearm from one day to another or 

longer, the firearm must be recorded as 

an ‘‘acquisition,’’ and then as a 

‘‘disposition’’ in the A&D records upon 

return to the same customer. PMFs are 

thereby treated similarly to 

commercially produced firearms when 

same-day adjustments or repairs are 

conducted. Additionally, the final rule 

clarifies that a PMF must be recorded as 

an acquisition whenever it is marked for 

identification, including same-day or 

on-the-spot. The only exception is when 

another licensee places markings for, 

and under the direct supervision of, the 

licensee who recorded the acquisition. 

In that circumstance, the licensee 

marking the firearm need not enter the 

PMF as an acquisition or mark the PMF 

with their own information. 

The rule also finalizes with minor 

changes the proposed amendment to 

§ 479.103 that allows manufacturers to 

delay submission of an ATF Form 2, 

Notice of Firearms Manufactured or 

Imported, if firearm muffler or silencer 

parts are transferred between qualified 

licensees for further manufacture or to 

complete new devices that are registered 

upon completion of the device, or to 

repair existing, registered devices. 

J. Record Retention 

This rule finalizes with few changes 

the proposed requirement in part 478 

that all licensees retain their records 

until business or licensed activity is 

discontinued, either on paper or in an 

electronic alternate method approved by 

the Director, at the business or 

collection premises readily accessible 

for inspection. The final rule made 

changes to § 478.50(a) to make clear that 

the warehouse for storage of firearms or 

ammunition inventory may also be used 

for the storage of records over 20 years 

of age. The warehouse may not be used 

to conduct other business activities, 

which would require a separate license 

and fee. 18 U.S.C. 923(a). 

K. Effect on Prior ATF Rulings and 

Procedures 

ATF publishes formal rulings and 

procedures to promote uniform 

understanding and application of the 

laws and regulations it administers, and 

to provide uniform methods for 

performing operations in compliance 

with the requirements of the law and 

regulations. ATF Rulings represent 

ATF’s guidance as to the application of 

the law and regulations to the entire 

state of facts involved, and apply 

retroactively unless otherwise 

indicated.148 Certain ATF Rulings and 

one ATF Procedure are impacted by this 

final rule, as follows: 

The following rulings are hereby 

superseded: ATF Ruling 2009–1 

(Firearms Manufacturing Activities— 

Camouflaging or Engraving Firearms); 

ATF Ruling 2009–5 (Firearms 

Manufacturing Activities, Identification 

Markings of Firearms); ATF Ruling 

2010–10 (Manufacturing Operations 

May be Performed by Licensed 

Gunsmiths Under Certain Conditions); 

ATF Ruling 2011–1 (Importers 

Consolidated Records); ATF Ruling 

2012–1 (Time Period for Marking 

Firearms Manufactured); ATF Ruling 

2013–3 (Adopting Identification of 

Firearms); and ATF Ruling 2016–3 

(Consolidation of Records Required for 

Manufacturers). 

The following rulings are hereby 

amplified: 149 ATF Ruling 2002–6 

(Identification of Firearms, Armor 

Piercing Ammunition, and Large 

Capacity Ammunition Feeding Devices); 

ATF Ruling 2016–1 (Requirements to 

Keep Firearms Records Electronically) 

and ATF Ruling 2016–2 (Electronic ATF 

Form 4473). 

The following rulings and procedure 

are hereby clarified: 150 Revenue Ruling 

55–342 (FFLs Assembling Firearms from 

Component Parts); ATF Ruling 77–1 

(Gunsmithing at Shooting Events); ATF 

Ruling 2009–2 (Installation of Drop In 

Replacement Parts); ATF Ruling 2010– 

3 (Identification of Maxim Side-Plate 

Receivers); ATF Ruling 2015–1 

(Manufacturing and Gunsmithing), and 

ATF Procedure 2020–1 (Recordkeeping 

Procedure for Non-Over-the-Counter 

Firearm Sales By Licensees to 

Unlicensed In-State Residents That Are 

NICS Exempt). 

L. Severability 

Based on the comments received in 

opposition to this rule, there is a 

reasonable possibility that this rule will 

be subject to litigation challenges. The 

Department has determined that this 

rule implements and is fully consistent 

with governing law. However, in the 

event any provision of this rule, an 

amendment or revision made by this 

rule, or the application of such 

provision or amendment or revision to 

any person or circumstance is held to be 

invalid or unenforceable by its terms, 

the remainder of this rule, the 

amendments or revisions made by this 

rule, and the application of the 

provisions of such rule to any person or 

circumstance shall not be affected and 

shall be construed so as to give them the 

maximum effect permitted by law. 

VI. Statutory and Executive Order 

Review 

A. Executive Orders 12866 and 13563 

Executive Orders 13563 (Improving 

Regulation and Regulatory Review) and 

12866 (Regulatory Planning and 

Review) direct agencies to assess the 

costs and benefits of available regulatory 

alternatives and, if regulation is 

necessary, to select regulatory 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24731 

approaches that maximize net benefits 

(including potential economic benefits, 

environmental benefits, public health 

and safety effects, distributive impacts, 

and equity). Executive Order 13563 

emphasizes the importance of 

quantifying both costs and benefits, 

reducing costs, harmonizing rules, and 

promoting flexibility. 

The Office of Information and 

Regulatory Affairs at OMB has 

determined that while this final rule is 

not economically significant, it is a 

‘‘significant regulatory action’’ under 

section 3(f)(4) of Executive Order 12866 

because this final rule raises novel legal 

or policy issues arising out of legal 

mandates. Accordingly, the rule has 

been reviewed by OMB. 

1. Need for Federal Regulatory Action 

In the NPRM, ATF stated that this 

rule would address externalities. Public 

comments stated that externalities deal 

with inefficiencies from market 

transactions, not actions dealing with 

the government. ATF concurs that this 

rule would not address externalities due 

to market inefficiencies; therefore, to 

avoid any confusion, ATF has removed 

language that suggested this rule would 

address a market inefficiency. 

Regardless, the publication of this final 

rule remains necessary to enforce the 

GCA and NFA. 

Agencies take regulatory action for 

various reasons. One of the reasons is to 

carry out Congress’s policy decisions, as 

expressed in statutes. Here, this 

rulemaking aims to implement 

Congress’s policy decision to require 

licensing, marking, recordkeeping, and 

background checks so that firearms can 

be traced if used in crime, and to 

prevent prohibited persons from 

acquiring them. 

This final rule is necessary is to 

address recent court cases, which have 

narrowly construed ATF’s current 

regulatory definition of ‘‘frame or 

receiver.’’ Such a narrow construction of 

the regulatory term creates the 

possibility that future courts may hold 

that the majority of regulated firearm 

frames or receivers do not meet the 

existing definition. Furthermore, 

administrative inspections, criminal 

investigations, and prosecutions are 

hindered when PMFs, which are 

untraceable, are accepted into and 

disposed of from a licensee’s inventory, 

and when firearms records are 

destroyed after 20 years despite the 

need of these records to combat criminal 

activities. 

This final rule updates the existing 

definition of ‘‘frame or receiver’’ to 

account for technological advances in 

the industry and ensure that firearms 

continue to remain under the regulatory 

regime as intended by the enactment of 

the GCA, including accounting for 

manufacturing of firearm parts kits and 

PMFs made from those kits. The narrow 

interpretation of what constitutes a 

‘‘frame or receiver’’ by some courts may 

potentially allow persons to avoid: (1) 

Having to obtain a license to engage in 

the business of manufacturing or 

importing frames or receivers; (2) 

identifying frames or receivers with a 

serial number and other traceable 

markings; (3) maintaining records of 

frames or receivers produced or 

imported through which they can be 

traced; and (4) running NICS checks on 

potential transferees to determine if they 

are legally prohibited from receiving or 

possessing firearms when they acquire 

frames or receivers. In turn, this would 

allow otherwise prohibited persons to 

acquire frames or receivers that can 

quickly be assembled into 

semiautomatic weapons easily and 

without a background check. 

If no portion of split or multi-piece 

frames or receivers were subject to any 

existing regulations, such as marking, 

recordkeeping, or background checks, 

law enforcement’s ability to trace 

semiautomatic firearms used in the 

commission of a crime would be 

severely impeded. This final rule makes 

consistent the marking requirements for 

firearms to facilitate tracing in the event 

a firearm is used in the commission of 

a crime. In order to accommodate the 

additional PMF marking requirements, 

this final rule clarifies and expands the 

definition of ‘‘gunsmithing.’’ In 

addition, this final rule requires FFLs to 

retain all firearms records, either in hard 

copy or electronically, until the Federal 

firearms licensed business or licensed 

activity is discontinued. For more 

specific details regarding the need for 

regulation, please refer to the specific 

chapters of the standalone RIA 

pertaining to each provision of this final 

rule. 

2. Summary of Affected Population, 

Costs, and Benefits 

Table 2 provides a summary of the 

affected population and anticipated 

costs and benefits of promulgating this 

rule. 

TABLE 2—SUMMARY OF AFFECTED POPULATION, COSTS, AND BENEFITS

Category Final rule 

Applicability ............................................................................................... • Definition of Frame or Receiver. 

• Updates Marking Requirements. 

• New Gunsmith Definition. 

• Updates Record Retention. 

Affected Population .................................................................................. • 113,204 FFLs. 

• 19,449 FFL Type 07 manufacturers. 

• 43 Non-FFL manufacturers. 

• 114,001 FFL dealers, pawnbrokers, and collectors. 

• 24 Non-FFL dealers. 

• Approximately 1 million individual owners. 

Total Costs to Industry, Public, and Government (7 percent Discount 

Rate).

$14.3 million annualized. 

Benefits (7 percent Discount Rate) .......................................................... Not estimated. 

Benefits (Qualitative) ................................................................................ • Provides clarity to courts on what constitutes a firearm frame or receiver. 

• Adapts to new technology/terminology. 

• Makes consistent marking requirements. 

• Eases certain marking requirements. 

• Increases tracing of crime scene firearms to prosecute criminals. 

• Restricts felons and other prohibited persons from acquiring PMFs. 


jspears on DSK121TN23PROD with RULES2
24732 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

3. Changes From the NPRM to FR 

Section V of this preamble describes 

the regulatory text of the final rule and 

the changes from the proposed rule. The 

following is a list of substantive 

changes: 

(1) Definition of ‘‘Frame or Receiver’’ 

• The final rule describes one part of 

a projectile weapon that will be either 

the ‘‘frame’’ or ‘‘receiver’’ with 

examples and pictures still provided. 

• The final rule defines ‘‘variant’’ and 

more clearly grandfathers existing 

classifications (e.g., AR–15/M–16 

variants). 

• The final rule clarifies the one part 

of a firearm muffler or silencer device 

that is the frame or receiver and 

addresses how modular silencers are 

marked. 

• The final rule defines ‘‘multi-piece 

frame or receiver’’ and specifically 

addresses how such parts must be 

marked. 

• The final rule clarifies the 

supplement titled ‘‘partially complete, 

disassembled, or inoperable [now 

‘nonfunctional’] frame or receiver’’ and 

provides examples. 

• The final rule clarifies the materials 

that need to be submitted when 

voluntarily seeking a firearm or armor 

piercing ammunition classification from 

ATF. 

(2) PMFs 

• The final rule requires FFLs to mark 

and record PMFs only when they are 

received or otherwise acquired into 

inventory, but allows PMFs to be 

adjusted or repaired and returned on the 

same day without marking. 

• The final rule allows FFLs to 

directly supervise a nonlicensee who 

may mark the PMF for the licensee in 

accordance with the regulations. 

• The final rule clarifies who is 

required to be licensed as a gunsmith 

eligible to mark PMFs without a 

manufacturer’s license. 

(3) Marking 

• The final rule defines ‘‘new design’’ 

to inform manufacturers as to when they 

are required to mark firearms they 

manufacture in accordance with the 

new marking requirements (i.e., either 

FFL name, city, and State; or FFL name 

and abbreviated FFL number placed on 

the frame or receiver). 

• The final rule expands adoption of 

marking allowances and addresses an 

additional three circumstances where 

markings can be adopted. These include 

newly manufactured firearms, 

manufacturers performing gunsmithing 

services, and PMFs marked by 

nonlicensees. 

• The final rule provides that an 

acceptable way for PMFs to be marked 

is by placing the serial number on a 

metal plate that is permanently 

embedded into a polymer frame or 

receiver, or other method approved by 

the Director. 

(4) Recordkeeping 

• The final rule clarifies that 

manufacturers have seven days to enter 

non-NFA firearms into their records, 

and by close of the next business day for 

manufactured NFA firearms. 

• The final rule clarifies that licensed 

dealers (including gunsmiths), 

manufacturers, and importers may 

conduct adjustments or repairs of all 

firearms without recording them as 

acquisitions or dispositions provided 

they are returned to the person from 

whom they were received on the same 

day. 

• The final rule clarifies that PMFs 

must be recorded as an acquisition 

when a licensee places marks of 

identification, and as a disposition upon 

return (unless the licensee is marking 

under the direct supervision of another 

licensee who recorded the acquisition). 

(5) Record Retention 

• The final rule clarifies that FFLs are 

required to maintain their records until 

licensed activity is discontinued. 

B. Executive Order 13132 

This regulation will not have 

substantial direct effects on the States, 

the relationship between the Federal 

Government and the States, or the 

distribution of power and 

responsibilities among the various 

levels of government. Therefore, in 

accordance with section 6 of Executive 

Order 13132 (Federalism), the Attorney 

General has determined that this 

regulation does not have sufficient 

federalism implications to warrant the 

preparation of a federalism summary 

impact statement. 

C. Executive Order 12988 

This regulation meets the applicable 

standards set forth in sections 3(a) and 

3(b)(2) of Executive Order 12988 (Civil 

Justice Reform). 

D. Regulatory Flexibility Act (‘‘RFA’’) 

The RFA establishes ‘‘as a principle of 

regulatory issuance that agencies shall 

endeavor, consistent with the objectives 

of the rule and of applicable statutes, to 

fit regulatory and informational 

requirements to the scale of the 

businesses, organizations, and 

governmental jurisdictions subject to 

regulation. To achieve this principle, 

agencies are required to solicit and 

consider flexible regulatory proposals 

and to explain the rationale for their 

actions to assure that such proposals are 

given serious consideration.’’ Public 

Law 96–354, sec. 2(b), 94 Stat. 1164, 

1165 (1980). 

Under the RFA, the agency is required 

to consider if this rule will have a 

significant economic impact on a 

substantial number of small entities. 

Agencies must perform a review to 

determine whether a rule will have such 

an impact. If the agency determines that 

it will, the agency must prepare a 

regulatory flexibility analysis as 

described in the RFA. 

Under the RFA (5 U.S.C. 604(a)), the 

final regulatory flexibility analysis 

(‘‘FRFA’’) must contain: 

• A statement of the need for, and 

objectives of, the rule; 

• a statement of the significant issues 

raised by the public comments in 

response to the initial regulatory 

flexibility analysis, a statement of the 

assessment of the agency of such issues, 

and a statement of any changes made in 

the proposed rule as a result of such 

comments; 

• the response of the agency to any 

comments filed by the Chief Counsel for 

Advocacy of the Small Business 

Administration in response to the 

proposed rule, and a detailed statement 

of any change made to the proposed rule 

in the final rule as a result of the 

comments; 

• a description of and an estimate of 

the number of small entities to which 

the rule will apply or an explanation of 

why no such estimate is available; 

• a description of the projected 

reporting, recordkeeping, and other 

compliance requirements of the rule, 

including an estimate of the classes of 

small entities which will be subject to 

the requirement and the type of 

professional skills necessary for 

preparation of the report or record; and 

• a description of the steps the agency 

has taken to minimize the significant 

economic impact on small entities 

consistent with the stated objectives of 

applicable statutes, including a 

statement of the factual, policy, and 

legal reasons for selecting the alternative 

adopted in the final rule and why each 

one of the other significant alternatives 

to the rule considered by the agency that 

affect the impact on small entities was 

rejected. 

ATF estimates that this final rule will 

have a significant impact on a 

substantial number of small businesses. 

Therefore, ATF has prepared an FRFA. 

For more details regarding the impacts 

to small businesses, please refer to the 

standalone RIA located on the docket. 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24733 

E. Small Business Regulatory 

Enforcement Fairness Act of 1996 

This rule is likely to have a significant 

economic impact on a substantial 

number of small entities under the 

Small Business Regulatory Enforcement 

Fairness Act of 1996 (‘‘SBREFA’’), 5 

U.S.C. 601 et seq. Accordingly, the 

Department prepared an initial 

regulatory flexibility analysis (IRFA) for 

the proposed rule and prepared an 

FRFA for the final rule. 5 U.S.C. 603– 

04. Furthermore, a small business 

compliance guide will be published as 

required by SBREFA. 

F. Congressional Review Act 

Pursuant to the Congressional Review 

Act, 5 U.S.C. 801 et seq., OMB’s Office 

of Information and Regulatory Affairs 

has determined this rule is not a ‘‘major 

rule,’’ as defined by 5 U.S.C. 804(2). 

This rule will not result in an annual 

effect on the economy of $100 million 

or more; a major increase in costs or 

prices; or significant adverse effects on 

competition, employment, investment, 

productivity, innovation, or on the 

ability of United States-based 

enterprises to compete with foreignbased enterprises in domestic and 

export markets. While there may be 

impacts on employment, investment, 

productivity, or innovation, these 

impacts will not have a significant 

impact on the overall economy. 

G. Unfunded Mandates Reform Act of 

1995 

This rule will not result in the 

expenditure by State, local, and Tribal 

governments, in the aggregate, or by the 

private sector, of $100 million or more 

in any one year (adjusted for inflation), 

and it will not significantly or uniquely 

affect small governments. Therefore, no 

actions were deemed necessary under 

the provisions of the Unfunded 

Mandates Reform Act of 1995, Public 

Law 104–4, 109 Stat. 48. 

H. Paperwork Reduction Act of 1995 

This rule would call for collections of 

information under the Paperwork 

Reduction Act of 1995, 44 U.S.C. 3501 

et seq. As defined in 5 CFR 1320.3(c), 

‘‘collection of information’’ comprises 

reporting, recordkeeping, monitoring, 

posting, labeling, and other similar 

actions. The title and description of the 

information collection, a description of 

those who must collect the information, 

and an estimate of the total annual 

burden follow. The estimate covers the 

time for reviewing instructions, 

searching existing sources of data, 

gathering and maintaining the data 

needed, and completing and reviewing 

the collection. 

Under the provisions of this proposed 

rule, there is a one-time increase in 

paperwork burdens of identification 

markings placed on firearms as well as 

additional transaction records. This 

requirement would be added to an 

existing approved collection covered by 

OMB control numbers 1140–0018, 

1140–0032, 1140–0050, and 1140–0067. 

Title: Application for a Federal 

Firearms License. 

OMB Control Number: OMB 1140– 

0018. 

Proposed Use of Information: This 

collection of information is necessary to 

ensure that anyone who wishes to be 

licensed as required by 18 U.S.C. 923 

meets the requirements to obtain the 

desired license. 

Description and Number of 

Respondents: Currently there are 13,000 

applications for a license. This final rule 

will effect a one-time increase in one 

respondent. 

Frequency of Response: There will be 

a recurring response for all currently 

existing FFLs. This final rule would 

affect a one-time number of one 

response (13,001 respondents * 1 

response). 

Burden of Response: This includes 

recurring time burden of one hour. ATF 

anticipates a one-time hourly burden of 

one hour per respondent. 

Estimate of Total Annual Burden: The 

current burden listed in this collection 

of information is 13,000 hours. The new 

burden, as a result of this final rule, is 

a one-time hourly burden of 13,001 

(13,001 respondents * 1 time response 

* 1 hourly burden per respondent). 

Title: Records of Acquisition and 

Disposition, Type 01/02 Dealer of 

Firearms. 

OMB Control Number: OMB 1140– 

0032. 

Proposed Use of Information: The 

recordkeeping requirements as 

contemplated by 18 U.S.C. 923, as 

amended, are for the primary purpose of 

facilitating ATF’s authority to inquire 

into the disposition of any firearm in the 

course of a criminal investigation, and 

conduct compliance inspections. 

Because the regulations require uniform 

formats for recordkeeping, the records 

serve a major secondary purpose: 

Granting ATF Officers the ability to 

examine records for firearms traces or 

compliance inspections, per 18 U.S.C. 

923(g)(1)(B), (C). 

Description and Number of 

Respondents: Currently there are 60,790 

respondents. The final rule will not 

increase the number of respondents, 

though we anticipate that 116 current 

respondents will have firearm parts kits 

and will therefore have an additional 

burden under this final rule. 

Frequency of Response: There will be 

a recurring response for all currently 

existing Type 01 and Type 02 FFLs. The 

frequency of response will be dependent 

on the inventory and sales of FFLs. 

Burden of Response: The burden of 

response was estimated at 60,790 hours 

for inspections. No burden was 

attributed to entries in records. 

Estimate of Total Annual Burden: The 

current burden listed in this collection 

of information is 60,790 hours. The new 

burden, as a result of the final rule, is 

an hourly burden of 116 hours (116 

respondents * 10 items * 2 responses * 

0.05 hourly burden per entry). 

Title: Identification Markings Placed 

on Firearms. 

OMB Control Number: OMB 1140– 

0050. 

Proposed Use of Information: ATF 

would use this information in fighting 

crime by facilitating the tracing of 

firearms used in criminal activities. The 

systematic tracing of firearms from the 

manufacturer or U.S. importer to the 

retail purchaser also enables law 

enforcement agencies to identify 

suspects involved in criminal 

violations, determine if a firearm is 

stolen, and provide other information 

relevant to a criminal investigation. 

Description and Number of 

Respondents: Currently there are 12,252 

licensed manufacturers of firearms and 

1,343 licensed importers. Of the 

potential number of licensed dealers 

and licensed pawnbrokers, ATF 

estimates that those directly affected 

would be a one-time surge of 42 

licensed dealers and 74 licensed 

pawnbrokers. The final rule would 

affect a one-time surge of 116 

respondents. 

Frequency of Response: There will be 

a recurring response for all currently 

existing 13,595 licensed manufacturers 

and licensed importers. The final rule 

would affect a one-time number of 1,160 

responses (116 one-time respondents 

*10 responses). There will be an annual 

increase of 101,136 responses (42 

respondents * 2,408 responses). 

Burden of Response: This includes a 

recurring time burden of one minute. 

Estimate of Total Annual Burden: The 

current burden listed in this collection 

of information is 85,630 hours. The new 

burden, as a result of the final rule, is 

a one-time hourly burden of 19 (116 

one-time respondents * 10 responses * 

0.016667 hourly burden per 

respondent). The new recurring burden 

as a result of the final rule is 1,686 hours 

(42 existing respondents * 2,408 

responses * 0.016667 hourly burden). 

Title: Licensed Firearms 

Manufacturers Records of Production, 

Disposition, and Supporting Data. 


jspears on DSK121TN23PROD with RULES2
24734 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

OMB Control Number: OMB 1140– 

0067. 

Proposed Use of Information: ATF 

would use this information for criminal 

investigation or regulatory compliance 

with the Gun Control Act of 1968. The 

Attorney General may inspect or 

examine the inventory and records of a 

licensed importer, licensed 

manufacturer, or licensed dealer, 

without such reasonable cause or 

warrant, and during the course of a 

criminal investigation of a person or 

persons other than the licensee, in order 

to ensure compliance with the 

recordkeeping requirements of 18 U.S.C. 

923(g)(1)(A). The Attorney General may 

also inspect or examine any records 

relating to firearms involved in a 

criminal investigation that are traced to 

the licensee, or firearms that may have 

been disposed of during the course of a 

bona fide criminal investigation. 18 

U.S.C. 923(g)(1)(B), (C). 

Description and Number of 

Respondents: The current number of 

respondents is 9,056 firearm 

manufacturers. The final rule will affect 

a subset of existing respondents (42 

respondents). 

Frequency of Response: There will be 

a recurring response for all 9,056 

licensed manufacturers. The final rule 

will effect an increase in records of 

202,272 responses. 

Burden of Response: This includes a 

recurring time burden of 1 minute. The 

burden resulting from the final rule is 

3,371 hours annually. 

Estimate of Total Annual Burden: The 

current burden listed in this collection 

of information is 201,205 hours. The 

new burden, as a result of the final rule, 

is 3,371 hours (42 respondents * 

0.016667 hours * 4,816 responses). 

Disclosure 

Copies of the final rule, proposed 

rule, and comments received in 

response to the proposed rule will be 

available for public inspection through 

the Federal eRulemaking portal, http:// 

regulations.gov, or by appointment 

during normal business hours at: ATF 

Reading Room, Room 1E–063, 99 New 

York Ave. NE, Washington, DC 20226; 

telephone: (202) 648–8740. 

List of Subjects 

27 CFR Part 447 

Administrative practice and 

procedure, Arms and munitions, 

Chemicals, Customs duties and 

inspection, Imports, Penalties, 

Reporting and recordkeeping 

requirements, Scientific equipment, 

Seizures and forfeitures. 

27 CFR Part 478 

Administrative practice and 

procedure, Arms and munitions, 

Exports, Freight, Imports, 

Intergovernmental relations, Law 

enforcement officers, Military 

personnel, Penalties, Reporting and 

recordkeeping requirements, Research, 

Seizures and forfeitures, Transportation. 

27 CFR Part 479 

Administrative practice and 

procedure, Arms and munitions, Excise 

taxes, Exports, Imports, Military 

personnel, Penalties, Reporting and 

recordkeeping requirements, Seizures 

and forfeitures, Transportation. 

Authority and Issuance 

Accordingly, for the reasons 

discussed in the preamble, 27 CFR parts 

447, 478, and 479 are amended as 

follows: 

PART 447—IMPORTATION OF ARMS, 

AMMUNITION AND IMPLEMENTS OF 

WAR 

■ 1. The authority citation for 27 CFR 

part 447 continues to read as follows: 

Authority: 22 U.S.C. 2778; E.O. 13637, 78 

FR 16129 (Mar. 8, 2013). 

■ 2. Amend § 447.11 by adding, in 

alphabetical order, definitions for 

‘‘Frame or receiver’’, and ‘‘Privately 

made firearm’’, to read as follows: 

§ 447.11 Meaning of terms. 

* * * * * 

Frame or receiver. The term ‘‘frame or 

receiver’’ shall have the same meaning 

as in 27 CFR 478.12. 

* * * * * 

Privately made firearm. The term 

‘‘privately made firearm’’ shall have the 

same meaning as in 27 CFR 478.11. 

* * * * * 

§ 447.42 [Amended] 

■ 3. In § 447.42 amend paragraph 

(a)(1)(iv)(A) by adding the phrase ‘‘of 

the defense article, or ‘‘privately made 

firearm’’ (if a firearm privately made in 

the United States)’’ after the word 

‘‘manufacturer’’. 

§ 447.45 [Amended] 

■ 4. In § 447.45 amend paragraph 

(a)(2)(ii) by adding the phrase ‘‘, or 

‘‘privately made firearm’’ (if a firearm 

privately made in the United States)’’ 

after ‘‘defense article’’. 

PART 478—COMMERCE IN FIREARMS 

AND AMMUNITION 

■ 5. The authority citation for 27 CFR 

part 478 continues to read as follows: 

Authority: 5 U.S.C. 552(a); 18 U.S.C. 847, 

921–931; 44 U.S.C. 3504(h). 

■ 6. Amend § 478.11 by: 

■ a. In the introductory text, removing 

the word ‘‘section’’ and adding, in its 

place, the word ‘‘subpart’’; 

■ b. Adding, in alphabetical order, 

definitions for ‘‘Complete muffler or 

silencer device’’ and ‘‘Complete 

weapon’’; 

■ c. In the definition of ‘‘Engaged in the 

business’’ revising paragraph (d); 

■ d. Revising the definition of 

‘‘Firearm’’; 

■ d. Removing the definition of 

‘‘Firearm frame or receiver’’; 

■ e. Adding, in alphabetical order, 

definitions for ‘‘Frame or receiver’’, 

‘‘Importer’s or manufacturer’s serial 

number’’, ‘‘Privately made firearm 

(PMF)’’, and ‘‘Readily’’; and 

The revisions and additions read as 

follows: 

§ 478.11 Meaning of terms. 

* * * * * 

Complete muffler or silencer device. A 

firearm muffler or firearm silencer that 

contains all component parts necessary 

to function, whether or not assembled or 

operable. 

Complete weapon. A firearm other 

than a firearm muffler or firearm 

silencer that contains all component 

parts necessary to function, whether or 

not assembled or operable. 

* * * * * 

Engaged in the business— * * * 

(d) Gunsmith. A person who, as a 

service performed on existing firearms 

not for sale or distribution, devotes 

time, attention, and labor to repairing or 

customizing firearms, making or fitting 

special barrels, stocks, or trigger 

mechanisms to firearms, or placing 

marks of identification on privately 

made firearms in accordance with this 

part, as a regular course of trade or 

business with the principal objective of 

livelihood and profit, but such term 

shall not include a person who 

occasionally repairs or customizes 

firearms (including identification), or 

occasionally makes or fits special 

barrels, stocks, or trigger mechanisms to 

firearms. In the case of firearms for 

purposes of sale or distribution, such 

term shall include a person who 

performs repairs (e.g., by replacing worn 

or broken parts) on complete weapons, 

or places marks of identification on 

privately made firearms, but shall not 

include a person who manufactures 

firearms (i.e., frames or receivers or 

complete weapons) by completion, 

assembly, or applying coatings, or 

otherwise making them suitable for use, 

requiring a license as a manufacturer; 

* * * * * 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24735 

Firearm. Any weapon, including a 

starter gun, which will or is designed to 

or may readily be converted to expel a 

projectile by the action of an explosive; 

the frame or receiver of any such 

weapon; any firearm muffler or firearm 

silencer; or any destructive device; but 

the term shall not include an antique 

firearm. In the case of a licensed 

collector, the term shall mean only 

curios and relics. The term shall include 

a weapon parts kit that is designed to or 

may readily be completed, assembled, 

restored, or otherwise converted to 

expel a projectile by the action of an 

explosive. The term shall not include a 

weapon, including a weapon parts kit, 

in which the frame or receiver of such 

weapon is destroyed as described in the 

definition ‘‘frame or receiver’’. 

* * * * * 

Frame or receiver. The term ‘‘frame or 

receiver’’ shall have the same meaning 

as in § 478.12. 

* * * * * 

Importer’s or manufacturer’s serial 

number. The serial number placed by a 

licensee on a firearm, including any full 

or abbreviated license number, any such 

identification on a privately made 

firearm, or a serial number issued by the 

Director. For purposes of 18 U.S.C. 

922(k) and § 478.34, the term shall 

include any associated licensee name, 

or licensee city or State placed on a 

firearm. 

* * * * * 

Privately made firearm (PMF). A 

firearm, including a frame or receiver, 

completed, assembled, or otherwise 

produced by a person other than a 

licensed manufacturer, and without a 

serial number placed by a licensed 

manufacturer at the time the firearm 

was produced. The term shall not 

include a firearm identified and 

registered in the National Firearms 

Registration and Transfer Record 

pursuant to chapter 53, title 26, United 

States Code, or any firearm 

manufactured or made before October 

22, 1968 (unless remanufactured after 

that date). 

* * * * * 

Readily. A process, action, or physical 

state that is fairly or reasonably 

efficient, quick, and easy, but not 

necessarily the most efficient, speediest, 

or easiest process, action, or physical 

state. With respect to the classification 

of firearms, factors relevant in making 

this determination include the 

following: 

(1) Time, i.e., how long it takes to 

finish the process; 

(2) Ease, i.e., how difficult it is to do 

so; 

(3) Expertise, i.e., what knowledge 

and skills are required; 

(4) Equipment, i.e., what tools are 

required; 

(5) Parts availability, i.e., whether 

additional parts are required, and how 

easily they can be obtained; 

(6) Expense, i.e., how much it costs; 

(7) Scope, i.e., the extent to which the 

subject of the process must be changed 

to finish it; and 

(8) Feasibility, i.e., whether the 

process would damage or destroy the 

subject of the process, or cause it to 

malfunction. 

* * * * * 

■ 7. Add § 478.12 to subpart B to read 

as follows: 

§ 478.12 Definition of Frame or Receiver. 

(a) Except as otherwise provided in 

this section, the term ‘‘frame or 

receiver’’ means the following— 

(1) The term ‘‘frame’’ means the part 

of a handgun, or variants thereof, that 

provides housing or a structure for the 

primary energized component designed 

to hold back the hammer, striker, bolt, 

or similar component prior to initiation 

of the firing sequence (i.e., sear or 

equivalent), even if pins or other 

attachments are required to connect 

such component to the housing or 

structure. 

(2) The term ‘‘receiver’’ means the 

part of a rifle, shotgun, or projectile 

weapon other than a handgun, or 

variants thereof, that provides housing 

or a structure for the primary 

component designed to block or seal the 

breech prior to initiation of the firing 

sequence (i.e., bolt, breechblock, or 

equivalent), even if pins or other 

attachments are required to connect 

such component to the housing or 

structure. 

(3) The terms ‘‘variant’’ and ‘‘variants 

thereof’’ mean a weapon utilizing a 

similar frame or receiver design 

irrespective of new or different model 

designations or configurations, 

characteristics, features, components, 

accessories, or attachments. For 

example, an AK-type firearm with a 

short stock and a pistol grip is a pistol 

variant of an AK-type rifle, an AR-type 

firearm with a short stock and a pistol 

grip is a pistol variant of an AR-type 

rifle, and a revolving cylinder shotgun 

is a shotgun variant of a revolver. 

(4) The following are nonexclusive 

examples that illustrate the above 

definitions: 

(i) Hinged or single framed revolvers: 

The frame is the part of the revolver that 

provides a structure designed to hold 

the sear. 

(ii) Colt 1911, Beretta/Browning/FN 

Herstal/Heckler & Koch/Ruger/Sig 

Sauer/Smith & Wesson/Taurus 

hammer-fired semiautomatic pistols: 

The frame is the lower portion of the 

pistol, or grip, that provides housing for 

the sear. 


jspears on DSK121TN23PROD with RULES2ER26AP22.001</GPH>
24736 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

(iii) Glock variant striker-fired 

semiautomatic pistols: The frame is the 

lower portion of the pistol, or grip, that 

provides housing for the sear. 

(iv) Sig Sauer P250/P320 variant 

semiautomatic pistols: The frame is the 

internal removable chassis of the pistol 

that provides housing for the energized 

component (i.e., sear or equivalent). 

(v) Bolt action rifles: The receiver is 

the part of the rifle that provides a 

structure for the bolt. 


jspears on DSK121TN23PROD with RULES2ER26AP22.002</GPH> ER26AP22.003</GPH> ER26AP22.004</GPH>
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24737 

(vi) Break action, lever action, or 

pump action rifles and shotguns: The 

receiver is the part of the rifle or 

shotgun that provides housing for the 

bolt, breechblock, or equivalent. 

(vii) AK variant firearms: The receiver 

is the part of the weapon that provides 

housing for the bolt. 

(viii) Steyr AUG variant firearms: The 

receiver is the central part of the 

weapon that provides housing for the 

bolt. 


jspears on DSK121TN23PROD with RULES2ER26AP22.005</GPH> ER26AP22.006</GPH> ER26AP22.007</GPH>
24738 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

(ix) Thompson machineguns and 

semiautomatic variants, and L1A1, FN 

FAL, FN FNC, MP38, MP40, and SIG 

550 firearms, and HK machineguns and 

semiautomatic variants: The receiver is 

the upper part of the weapon that 

provides housing for the bolt. 

(x) Sten, Sterling, and Kel-Tec SUB– 

2000 firearms: The receiver is the 

central part of the weapon, or tube, that 

provides housing for the bolt. 


jspears on DSK121TN23PROD with RULES2ER26AP22.008</GPH> ER26AP22.009</GPH> ER26AP22.010</GPH>
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24739 

(b) Firearm muffler or silencer frame 

or receiver. The terms ‘‘frame’’ and 

‘‘receiver’’ shall mean, in the case of a 

firearm muffler or firearm silencer, the 

part of the firearm, such as an outer tube 

or modular piece, that provides housing 

or a structure for the primary internal 

component designed to reduce the 

sound of a projectile (i.e., baffles, 

baffling material, expansion chamber, or 

equivalent). In the case of a modular 

firearm muffler or firearm silencer 

device with more than one such part, 

the terms shall mean the principal 

housing attached to the weapon that 

expels a projectile, even if an adapter or 

other attachments are required to 

connect the part to the weapon. The 

terms shall not include a removable end 

cap of an outer tube or modular piece. 

(c) Partially complete, disassembled, 

or nonfunctional frame or receiver. The 

terms ‘‘frame’’ and ‘‘receiver’’ shall 

include a partially complete, 

disassembled, or nonfunctional frame or 

receiver, including a frame or receiver 

parts kit, that is designed to or may 

readily be completed, assembled, 

restored, or otherwise converted to 

function as a frame or receiver, i.e., to 

house or provide a structure for the 

primary energized component of a 

handgun, breech blocking or sealing 

component of a projectile weapon other 

than a handgun, or internal sound 

reduction component of a firearm 

muffler or firearm silencer, as the case 

may be. The terms shall not include a 

forging, casting, printing, extrusion, 

unmachined body, or similar article that 

has not yet reached a stage of 

manufacture where it is clearly 

identifiable as an unfinished component 

part of a weapon (e.g., unformed block 

of metal, liquid polymer, or other raw 

material). When issuing a classification, 

the Director may consider any 

associated templates, jigs, molds, 

equipment, tools, instructions, guides, 

or marketing materials that are sold, 

distributed, or possessed with the item 

or kit, or otherwise made available by 

the seller or distributor of the item or kit 

to the purchaser or recipient of the item 

or kit. The following are nonexclusive 

examples that illustrate the definitions: 

Example 1 to paragraph (c)—Frame or 

receiver: A frame or receiver parts kit 

containing a partially complete or 

disassembled billet or blank of a frame 

or receiver that is sold, distributed, or 

possessed with a compatible jig or 

template is a frame or receiver, as a 

person with online instructions and 

common hand tools may readily 

complete or assemble the frame or 

receiver parts to function as a frame or 

receiver. 

Example 2 to paragraph (c)—Frame or 

receiver: A partially complete billet or 

blank of a frame or receiver with one or 

more template holes drilled or indexed 

in the correct location is a frame or 

receiver, as a person with common hand 

tools may readily complete the billet or 

blank to function as a frame or receiver. 

Example 3 to paragraph (c)—Frame or 

receiver: A complete frame or receiver of 

a weapon that has been disassembled, 

damaged, split, or cut into pieces, but 

not destroyed in accordance with 

paragraph (e), is a frame or receiver. 

Example 4 to paragraph (c)—Not a 

receiver: A billet or blank of an AR–15 

variant receiver without critical interior 

areas having been indexed, machined, 

or formed that is not sold, distributed, 

or possessed with instructions, jigs, 

templates, equipment, or tools such that 

it may readily be completed is not a 

receiver. 

Example 5 to paragraph (c)—Not a 

receiver: A flat blank of an AK variant 

receiver without laser cuts or indexing 

that is not sold, distributed, or 

possessed with instructions, jigs, 

templates, equipment, or tools is not a 

receiver, as a person cannot readily fold 

the flat to provide housing or a structure 

for the primary component designed to 

block or seal the breech prior to 

initiation of the firing sequence. 

(d) Multi-piece frame or receiver. The 

term ‘‘multi-piece frame or receiver’’ 

shall mean a frame or receiver that may 

be disassembled into multiple modular 

subparts, i.e., standardized units that 

may be replaced or exchanged. The term 

shall not include the internal frame of 

a pistol that is a complete removable 

chassis that provides housing for the 

energized component, unless the chassis 

itself may be disassembled. The 

modular subpart(s) identified in 

accordance with § 478.92 with an 

importer’s or manufacturer’s serial 

number shall be presumed, absent an 

official determination by the Director or 

other reliable evidence to the contrary, 

to be part of the frame or receiver of a 

weapon or device. 

(e) Destroyed frame or receiver. The 

terms ‘‘frame’’ and ‘‘receiver’’ shall not 

include a frame or receiver that is 

destroyed. For purposes of these 

definitions, the term ‘‘destroyed’’ means 

that the frame or receiver has been 

permanently altered such that it may 

not readily be completed, assembled, 

restored, or otherwise converted to 

function as a frame or receiver. 

Acceptable methods of destruction 

include completely melting, crushing, 

or shredding the frame or receiver, or 

other method approved by the Director. 

(f)(1) Frame or receiver classifications 

based on which part of the weapon was 

classified as such before April 26, 2022. 

Except as provided in paragraph (f)(2) of 

this section, the terms ‘‘frame’’ and 

‘‘receiver’’ shall include the specific 

part of a complete weapon, including 

variants thereof, determined (classified) 

by the Director to be defined as a 

firearm frame or receiver prior to April 

26, 2022. Any such part that is 

identified with an importer’s or 

manufacturer’s serial number shall be 

presumed, absent an official 

determination by the Director or other 

reliable evidence to the contrary, to be 

the frame or receiver of the weapon. The 

following is a nonexclusive list of such 

weapons and the specific part 

determined by the Director to be the 

firearm frame or receiver as they existed 

on that date: 

(i) AR–15/M–16 variant firearms: The 

receiver is the lower part of the weapon 

that provides housing for the trigger 

mechanism and hammer (i.e., lower 

receiver). 


jspears on DSK121TN23PROD with RULES2
24740 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

(ii) Ruger Mark IV pistol: The frame is 

the upper part of the weapon that 

provides housing for the bolt or 

breechblock. 

(iii) Benelli 121 M1 Shotgun: The 

receiver is the lower part of the weapon 

that provides housing for the trigger 

mechanism. 

(iv) Vickers/Maxim, Browning 1919, 

M2, and box-type machineguns and 

semiautomatic variants: The receiver is 

the side plate of the weapon that is 

designed to hold the charging handle. 


jspears on DSK121TN23PROD with RULES2ER26AP22.011</GPH> ER26AP22.012</GPH> ER26AP22.013</GPH>
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24741 

(2) Frame or receiver classifications of 

partially complete, disassembled, or 

nonfunctional frames or receivers before 

April 26, 2022. Prior determinations by 

the Director that a partially complete, 

disassembled, or nonfunctional frame or 

receiver, including a parts kit, was not, 

or did not include, a ‘‘firearm frame or 

receiver’’ under § 478.11, or ‘‘frame or 

receiver’’ under § 479.11 of this 

subchapter, as those terms were defined 

prior to April 26, 2022, shall not 

continue to be valid or authoritative 

after that date. Such determinations 

shall include those in which the 

Director determined that the item or 

parts kit had not yet reached a stage of 

manufacture to be, or include, a 

‘‘firearm frame or receiver’’ under 

§ 478.11, or ‘‘frame or receiver’’ under 

§ 479.11 of this subchapter, as those 

terms were defined prior to [date of 

publication of the rule]. 

§ 478.47 [Amended] 

■ 8. In § 478.47 amend paragraph (a) by 

removing the words ‘‘serial number’’ 

and adding in its place ‘‘unique license 

number’’. 

§ 478.50 [Amended] 

■ 9. In § 478.50 amend paragraph (a) by 

adding the phrase ‘‘, or if such 

warehouse is used by the licensee for 

the storage of records as provided in 

§ 478.129’’ after the phrase ‘‘at the 

licensed premises served by such 

warehouse’’. 

§ 478.92 [Amended] 

■ 10. Amend § 478.92 by revising 

paragraph (a) and adding paragraph (c) 

to read as follows: 

§ 478.92 Identification of firearms and 

armor piercing ammunition. 

(a)(1) Firearms manufactured or 

imported by licensees. Except as 

otherwise provided in this section, 

licensed manufacturers and licensed 

importers of firearms must legibly 

identify each firearm they manufacture 

or import as follows: 

(i) Serial number, name, place of 

business. By engraving, casting, 

stamping (impressing), or otherwise 

conspicuously placing or causing to be 

engraved, cast, stamped (impressed) or 

otherwise placed on the frame or 

receiver thereof, an individual serial 

number, in a manner not susceptible of 

being readily obliterated, altered, or 

removed. The serial number must not 

duplicate any serial number placed by 

the licensee on any other firearm. The 

frame or receiver must also be marked 

with either: their name (or recognized 

abbreviation), and city and State (or 

recognized abbreviation) where they 

maintain their place of business; or their 

name (or recognized abbreviation) and 

the serial number beginning with their 

abbreviated Federal firearms license 

number, which is the first three and last 

five digits, as a prefix to the unique 

identification number, followed by a 

hyphen, e.g., ‘‘12345678-[unique 

identification number]’’; and 

(ii) Model, caliber or gauge, foreign 

manufacturer, country of manufacture. 

By engraving, casting, stamping 

(impressing), or otherwise 

conspicuously placing or causing to be 

engraved, cast, stamped (impressed) or 

placed on the frame or receiver, or 

barrel or pistol slide (if applicable) 

thereof, certain additional information. 

This information must be placed in a 

manner not susceptible of being readily 

obliterated, altered, or removed. The 

additional information shall include: 

(A) The model, if such designation 

has been made; 

(B) The caliber or gauge; 

(C) When applicable, the name of the 

foreign manufacturer; and 

(D) In the case of an imported firearm, 

the name of the country in which it was 

manufactured. For additional 

requirements relating to imported 

firearms, see Customs regulations at 19 

CFR part 134. 

(iii) Multi-piece frame or receiver. In 

the case of a multi-piece frame or 

receiver, the modular subpart that is the 

outermost housing or structure designed 

to house, hold, or contain either the 

primary energized component of a 

handgun, breech blocking or sealing 

component of a projectile weapon other 

than a handgun, or internal sound 

reduction component of a firearm 

muffler or firearm silencer, as the case 

may be, shall be the subpart of the 

multi-piece frame or receiver identified 

in accordance with this section. If more 

than one subpart is similarly designed 

to house, hold, or contain such primary 

component (e.g., left and right halves), 

each of those subparts must be 

identified with the same serial number 

and associated licensee information not 

duplicated on any other frame or 

receiver. The identified subpart(s) of a 

complete (assembled or unassembled) 

multi-piece frame or receiver shall not 

be removed and replaced (see § 478.34, 

18 U.S.C. 922(k), and 26 U.S.C. 5861(g) 

and (h)), unless— 

(A) The subpart replacement is not a 

firearm under 26 U.S.C. 5845; 

(B) The subpart replacement is 

identified by the licensed manufacturer 

of the original subpart with the same 

serial number and associated licensee 

information in the manner prescribed by 

this section; and 

(C) The original subpart is destroyed 

under the licensed manufacturer’s 

control or direct supervision prior to 

such placement. 

(iv) Frame or receiver, machinegun 

conversion part, or muffler or silencer 

part disposed of separately. Each part 

defined as a frame or receiver or 

modular subpart thereof described in 

paragraph (a)(1)(iii) of this section, 

machinegun, or firearm muffler or 

firearm silencer that is not a component 

part of a complete weapon or complete 

muffler or silencer device at the time it 

is sold, shipped, or otherwise disposed 

of by the licensee must be identified as 

required by this section with an 

individual serial number not duplicated 

on any other firearm and all additional 

identifying information, except that the 

model designation and caliber or gauge 

may be omitted if that information is 


jspears on DSK121TN23PROD with RULES2ER26AP22.014</GPH>
24742 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

unknown at the time the part is 

identified. 

(v) Size and depth of markings. The 

engraving, casting, or stamping 

(impressing) of the serial number and 

additional information must be to a 

minimum depth of .003 inch, and the 

serial number and any associated 

license number in a print size no 

smaller than 1⁄16 inch. The size of the 

serial and license number is measured 

as the distance between the latitudinal 

ends of the character impression 

bottoms (bases). The depth of all 

markings required by this section is 

measured from the flat surface of the 

metal and not the peaks or ridges. 

(vi) Period of time to identify firearms. 

Licensed manufacturers shall identify 

firearms they manufacture within the 

period of time set forth in the following 

subparagraphs (A) and (B), and licensed 

importers must identify firearms they 

import within the period prescribed in 

§ 478.112. For purposes of these 

subparagraphs, firearms awaiting 

materials, parts, or equipment repair to 

be completed are presumed, absent 

reliable evidence to the contrary, to be 

in the manufacturing process. 

(A) Complete non-National Firearms 

Act weapons, and frames or receivers of 

such weapons. Complete weapons not 

defined as firearms under 26 U.S.C. 

5845 shall be identified not later than 

the seventh day following the date the 

entire manufacturing process has ended 

for the weapon, or prior to disposition, 

whichever is sooner. Each part, 

including a replacement part, defined as 

a frame or receiver or modular subpart 

thereof described in paragraph (a)(1)(iii) 

of this section (other than a machinegun 

or firearm muffler or firearm silencer) 

that is not a component part of a 

complete weapon at the time it is sold, 

shipped, or otherwise disposed of shall 

be identified not later than the seventh 

day following the date the entire 

manufacturing process has ended for the 

frame or receiver or modular subpart, or 

prior to disposition, whichever is 

sooner. 

(B) Complete National Firearms Act 

weapons and devices, and machinegun 

and muffler or silencer parts. Complete 

weapons defined as firearms under 26 

U.S.C. 5845, and complete muffler or 

silencer devices, shall be identified not 

later than close of the next business day 

following the date the entire 

manufacturing process has ended for the 

weapon or device, or prior to 

disposition, whichever is sooner. Each 

part or modular subpart defined as a 

machinegun (i.e., frame or receiver or 

conversion part), or firearm muffler or 

firearm silencer, that is not a component 

part of a complete weapon or complete 

firearm muffler or silencer device at the 

time it is sold, shipped, or otherwise 

disposed of shall be identified not later 

than close of the next business day 

following the date the entire 

manufacturing process has ended for the 

part, or prior to disposition, whichever 

is sooner. 

(2) Privately made firearms (PMFs). 

Unless previously identified by another 

licensee in accordance with, and except 

as otherwise provided by, this section, 

licensees must legibly and 

conspicuously identify each privately 

made firearm or ‘‘PMF’’ received or 

otherwise acquired (including from a 

personal collection) not later than the 

seventh day following the date of 

receipt or other acquisition, or before 

the date of disposition (including to a 

personal collection), whichever is 

sooner. PMFs must be identified by 

placing, or causing to be placed under 

the licensee’s direct supervision, an 

individual serial number on the frame 

or receiver, which must not duplicate 

any serial number placed by the 

licensee on any other firearm. The serial 

number must begin with the licensee’s 

abbreviated Federal firearms license 

number, which is the first three and last 

five digits, as a prefix to a unique 

identification number, followed by a 

hyphen, e.g., ‘‘12345678-[unique 

identification number]’’. The serial 

number must be placed in a manner 

otherwise in accordance with this 

section, including the requirements that 

the serial number be at the minimum 

size and depth, and not susceptible of 

being readily obliterated, altered, or 

removed. An acceptable method of 

identifying a PMF is by placing the 

serial number on a metal plate that is 

permanently embedded into a polymer 

frame or receiver, or other method 

approved by the Director. 

(3) Meaning of marking terms. For 

purposes of this section, the term 

‘‘identify’’ means placing marks of 

identification, the terms ‘‘legible’’ and 

‘‘legibly’’ mean that the identification 

markings (including a unique 

identification number) use exclusively 

Roman letters (e.g., A, a, B, b, C, c) and 

Arabic numerals (e.g., 1, 2, 3), or solely 

Arabic numerals, and may include a 

hyphen, and the terms ‘‘conspicuous’’ 

and ‘‘conspicuously’’ mean that the 

identification markings are capable of 

being easily seen with the naked eye 

during normal handling of the firearm, 

and are unobstructed by other markings 

when the complete weapon or device is 

assembled. 

(4) Exceptions—(i) Alternate means of 

identification. The Director may 

authorize other means of identification 

to identify firearms upon receipt of a 

letter application or prescribed form 

from the licensee showing that such 

other identification is reasonable and 

will not hinder the effective 

administration of this part. 

(ii) Destructive devices. In the case of 

a destructive device, the Director may 

authorize other means of identification 

to identify that weapon upon receipt of 

a letter application or prescribed form 

from the licensee. The application shall 

show that engraving, casting, or 

stamping (impressing) such a weapon as 

required by this section would be 

dangerous or impracticable and that the 

alternate means of identification 

proposed will not hinder the effective 

administration of this part. 

(iii) Adoption of identifying markings. 

Licensees may adopt existing markings 

previously placed on a firearm and are 

not required to mark a serial number or 

other identifying markings in 

accordance with this section, as follows: 

(A) Newly manufactured firearms: 

Licensed manufacturers may adopt the 

serial number and other identifying 

markings previously placed on a firearm 

by another licensed manufacturer 

provided the firearm has not been sold, 

shipped, or otherwise disposed of to a 

person other than a licensee, and the 

serial number adopted is not duplicated 

on any other firearm. 

(B) Remanufactured or imported 

firearms. Licensed manufacturers and 

licensed importers may adopt the serial 

number or other identifying markings 

previously placed on a firearm that 

otherwise meets the requirements of this 

section that has been sold, shipped, or 

otherwise disposed of to a person other 

than a licensee provided that, within the 

period and in the manner herein 

prescribed, the licensee legibly and 

conspicuously places, or causes to be 

placed, on the frame or receiver either: 

Their name (or recognized 

abbreviation), and city and State (or 

recognized abbreviation) where they 

maintain their place of business; or their 

name (or recognized abbreviation) and 

abbreviated Federal firearms license 

number, which is the first three and last 

five digits, individually (i.e., not as a 

prefix to the serial number adopted) 

after the letters ‘‘FFL’’, in the following 

format: ‘‘FFL12345678’’. The serial 

number adopted must not duplicate any 

serial number adopted or placed on any 

other firearm, except that if a licensed 

importer receives two or more firearms 

with the same foreign manufacturer’s 

serial number, the importer may adopt 

the serial number by adding letters or 

numbers to that serial number, and may 

include a hyphen. 

(C) Manufacturers performing 

gunsmithing services. Licensed 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24743 

manufacturers may adopt the serial 

number or other identifying markings 

previously placed on a firearm by 

another licensee provided the 

manufacturer is performing services for 

a nonlicensee as a gunsmith (as defined 

in § 478.11) on existing firearms not for 

sale or distribution. 

(D) Privately made firearms marked 

by nonlicensees. Unless previously 

identified by another licensee in 

accordance with this section, licensees 

may adopt a unique identification 

number previously placed on a privately 

made firearm by an unlicensed person, 

but not duplicated on any other firearm 

of the licensee, that otherwise meets the 

identification requirements of this 

section provided that, within the period 

and in the manner herein prescribed, 

the licensee legibly and conspicuously 

places, or causes to be placed, on the 

frame or receiver thereof a serial number 

beginning with their abbreviated 

Federal firearms license number, which 

is the first three and last five digits, 

followed by a hyphen, before the 

existing unique identification number, 

e.g., ‘‘12345678-[unique identification 

number]’’. 

(iv)(A) Firearm muffler or silencer 

parts transferred between qualified 

manufacturers for further manufacture 

or to complete new devices. Licensed 

manufacturers qualified under 27 CFR 

part 479 may transfer a part defined as 

a firearm muffler or firearm silencer to 

another qualified manufacturer without 

immediately identifying or registering 

such part provided that it is for further 

manufacture (i.e., machining, coating, 

etc.) or manufacturing a complete 

muffler or silencer device. Once the new 

device with such part is completed, the 

manufacturer who completes the device 

shall identify, record, and register it in 

the manner and within the period 

specified in this part for a complete 

muffler or silencer device. 

(B) Firearm muffler or silencer 

replacement parts transferred to 

qualified manufacturers or dealers to 

repair existing devices. Licensed 

manufacturers qualified under part 479 

may transfer a replacement part defined 

as a firearm muffler or firearm silencer 

other than a frame or receiver to a 

qualified manufacturer or dealer 

without identifying or registering such 

part provided that it is for repairing a 

complete muffler or silencer device that 

was previously identified, recorded, and 

registered in accordance with this part 

and part 479. 

(v) Frames or receivers designed 

before August 24, 2022. Licensed 

manufacturers and licensed importers 

may continue to identify the same 

component of a firearm (other than a 

PMF) defined as a frame or receiver as 

it existed before August 24, 2022 with 

the same information required to be 

marked by paragraphs (a)(1)(i) and 

(a)(1)(ii) of this section that were in 

effect prior to that date, and any rules 

necessary to ensure such identification 

shall remain effective for that purpose. 

Any frame or receiver with a new design 

manufactured after August 24, 2022 

must be marked with the identifying 

information and within the period 

prescribed by this section. For purposes 

of this paragraph, the term ‘‘new 

design’’ means that the design of the 

existing frame or receiver has been 

functionally modified or altered, as 

distinguished from performing a 

cosmetic process that adds to or changes 

the decoration of the frame or receiver 

(e.g., painting or engraving), or by 

adding or replacing stocks, barrels, or 

accessories to the frame or receiver. 

(vi) Privately made firearms acquired 

before August 24, 2022. Licensees shall 

identify in the manner prescribed by 

this section, or cause another person to 

so identify, each privately made firearm 

received or otherwise acquired 

(including from a personal collection) 

by the licensee before August 24, 

2022within sixty (60) days from that 

date, or prior to the date of final 

disposition (including to a personal 

collection), whichever is sooner. 

* * * * * 

(c) Voluntary classification of firearms 

and armor piercing ammunition. The 

Director may issue a determination 

(classification) to a person whether an 

item, including a kit, is a firearm or 

armor piercing ammunition as defined 

in this part upon receipt of a written 

request or form prescribed by the 

Director. Each such voluntary request or 

form submitted shall be executed under 

the penalties of perjury with a complete 

and accurate description of the item or 

kit, the name and address of the 

manufacturer or importer thereof, and a 

sample of such item or kit for 

examination. A firearm sample must 

include all accessories and attachments 

relevant to such classification as each 

classification is limited to the firearm in 

the configuration submitted. Each 

request for classification of a partially 

complete, disassembled, or 

nonfunctional item or kit must contain 

any associated templates, jigs, molds, 

equipment, or tools that are made 

available by the seller or distributor of 

the item or kit to the purchaser or 

recipient of the item or kit, and any 

instructions, guides, or marketing 

materials if they will be made available 

by the seller or distributor with the item 

or kit. Upon completion of the 

examination, the Director may return 

the sample to the person who made the 

request unless a determination is made 

that return of the sample would be or 

place the person in violation of law. 

Submissions of armor piercing 

ammunition with a projectile or 

projectile core constructed entirely from 

one or a combination of tungsten steel 

alloys, steel, iron, brass, bronze, 

beryllium copper, or depleted uranium 

must include a list of known handguns 

in which the ammunition may be used. 

Except for the classification of a specific 

component as the frame or receiver of a 

particular weapon, a determination 

made by the Director under this 

paragraph shall not be deemed by any 

person to be applicable to or 

authoritative with respect to any other 

sample, design, model, or configuration. 

■ 11. Revise § 478.122 to read as 

follows: 

§ 478.122 Records maintained by 

importers. 

(a) Except for adjustment or repair of 

a firearm that is returned to the person 

from whom it was received on the same 

day, each licensed importer shall record 

the name of the importer and 

manufacturer, type, model, caliber or 

gauge, country or countries of 

manufacture (if imported), and serial 

number (including any associated 

license number either as a prefix, or if 

remanufactured or imported, separated 

by a semicolon) of each firearm 

imported or otherwise acquired 

(including a frame or receiver to be 

disposed of separately), the date of such 

importation or other acquisition, and if 

otherwise acquired, the name and 

address, or the name and license 

number of the person from whom it was 

received. Privately made firearms shall 

be recorded in accordance with 

§ 478.125(i). The information required 

by this paragraph shall be recorded not 

later than 15 days following the date of 

importation or other acquisition in a 

format containing the applicable 

columns set forth in paragraph (b) of 

this section. 

(b) A record of each firearm disposed 

of by an importer and a separate record 

of armor piercing ammunition 

dispositions to governmental entities, 

for exportation, or for testing or 

experimentation authorized under the 

provisions of § 478.149 shall be 

maintained by the licensed importer on 

the licensed premises. The record shall 

show the date of such sale or other 

disposition, and the name and license 

number of the licensee to whom the 

firearm was transferred, or if disposed of 

to a nonlicensee, the name and address 

of the person, or the transaction number 


jspears on DSK121TN23PROD with RULES2
24744 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

of the Firearms Transaction Record, 

Form 4473, if the licensee transferring 

the firearm sequentially numbers the 

Forms 4473 and files them numerically. 

In the event the licensee records a 

duplicate entry with the same firearm 

and acquisition information, whether to 

close out an old record book or for any 

other reason, the licensee shall record a 

reference to the date and location of the 

subsequent entry (e.g., date of new 

entry, book name/number, page number, 

and line number) as the disposition. The 

information required by this paragraph 

(b) shall be entered in the proper record 

book not later than the seventh day 

following the date of the transaction. 

Such information shall be recorded in 

formats containing the applicable 

columns below, except that for armor 

piercing ammunition, the information 

and format shall also include the 

quantity of projectiles: 

TABLE 1 TO PARAGRAPH (b)—FIREARMS IMPORTER OR MANUFACTURER ACQUISITION AND DISPOSITION RECORD

Description of firearm Import/manufacture/acquisition Disposition 

Importer, 

manufacturer, and/ 

or ‘‘privately made 

firearm’’ (PMF) 

(if privately made in 

the U.S.) 

Type Model Caliber or 

gauge 

Country or 

countries of 

manufacture 

(if imported) 

Serial No. 

Date of import, 

manufacture, 

or acquisition 

Name and 

address of 

nonlicensee; 

or if licensee, 

name and 

license No. 

(if acquired) 

Date of 

disposition Name 

Address of 

nonlicensee; 

license No. of 

licensee; or 

Form 4473 

transaction 

No. if such 

forms filed 

numerically 

TABLE 2 TO PARAGRAPH (b)—ARMOR PIERCING AMMUNITION IMPORTER OR MANUFACTURER DISPOSITION RECORD

Date of 

disposition Manufacturer Caliber or gauge 

Quantity of 

projectiles Transferee—name and address 

(c) The Director may authorize 

alternate records to be maintained by a 

licensed importer to record the 

acquisition and disposition of firearms 

and armor piercing ammunition when it 

is shown by the licensed importer that 

such alternate records will accurately 

and readily disclose the information 

required by this section. A licensed 

importer who proposes to use alternate 

records shall submit a letter application 

to the Director and shall describe the 

proposed alternate records and the need 

therefor. Such alternate records shall 

not be employed by the licensed 

importer until approval in such regard 

is received from the Director. 

■ 12. Revise § 478.123 to read as 

follows: 

§ 478.123 Records maintained by 

manufacturers. 

(a) Except for adjustment or repair of 

a firearm that is returned to the person 

from whom it was received on the same 

day, each licensed manufacturer shall 

record the name of the manufacturer 

and importer (if any), type, model, 

caliber or gauge, and serial number 

(including any associated license 

number either as a prefix, or if 

remanufactured or imported, separated 

by a semicolon) of each firearm 

manufactured or otherwise acquired 

(including a frame or receiver to be 

disposed of separately), the date of such 

manufacture or other acquisition, and if 

otherwise acquired, the name and 

address or the name and license number 

of the person from whom it was 

received. Privately made firearms shall 

be recorded in accordance with 

§ 478.125(i). The information required 

by this paragraph shall, in the case of a 

firearm other than a firearm defined in 

26 U.S.C. 5845, be recorded not later 

than the seventh day following the date 

of such manufacture or other 

acquisition. In the case of a firearm 

defined in 26 U.S.C. 5845, such 

information shall be recorded by close 

of the next business day following the 

date of such manufacture or other 

acquisition, except that, when a 

commercial record is held by the 

licensed manufacturer separately from 

other commercial documents and 

readily available for inspection, 

containing all acquisition information 

required for the record, the period for 

making the required entry into the 

record may be delayed not to exceed the 

seventh day following the date of 

receipt. The information required by 

this paragraph shall be recorded in a 

format containing the applicable 

columns prescribed by § 478.122. 

(b) A record of each firearm disposed 

of by a manufacturer and a separate 

record of armor piercing ammunition 

dispositions to governmental entities, 

for exportation, or for testing or 

experimentation authorized under the 

provisions of § 478.149 shall be 

maintained by the licensed 

manufacturer on the licensed premises. 

The record shall show the date of such 

sale or other disposition, and the name 

and license number of the licensee to 

whom the firearms were transferred, or 

if disposed of to a nonlicensee, the 

name and address of the person, or the 

transaction number of the Firearms 

Transaction Record, Form 4473, if the 

licensee transferring the firearm 

sequentially numbers the Forms 4473 

and files them numerically. In the event 

the licensee records a duplicate entry 

with the same firearm and acquisition 

information, whether to close out an old 

record book or for any other reason, the 

licensee shall record a reference to the 

date and location of the subsequent 

entry (e.g., date of new entry, book 

name/number, page number, and line 

number) as the disposition. The 

information required by this paragraph 

shall be entered in the proper record 

book not later than the seventh day 

following the date of the transaction. 

Such information shall be recorded in a 

format containing the applicable 

columns prescribed by § 478.122, except 

that for armor piercing ammunition, the 

information and format shall also 

include the quantity of projectiles. 

(c) The Director may authorize 

alternate records to be maintained by a 

licensed manufacturer to record the 

acquisition or disposition of firearms 

and armor piercing ammunition when it 

is shown by the licensed manufacturer 

that such alternate records will 

accurately and readily disclose the 

information required by this section. A 

licensed manufacturer who proposes to 

use alternate records shall submit a 

letter application to the Director and 

shall describe the proposed alternate 

record and the need therefor. Such 

alternate records shall not be employed 

by the licensed manufacturer until 

approval in such regard is received from 

the Director. 

■ 13. Amend § 478.124 by: 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24745 

■ a. In paragraph (b) removing the word 

‘‘serial’’ before ‘‘number’’; 

■ b. Revising paragraph (c)(4); and 

■ c. In paragraph (f) revising the fourth 

sentence and adding a new fifth 

sentence. 

The addition and revision read as 

follows: 

§ 478.124 Firearms transaction record. 

* * * * * 

(c) * * * 

(4) The licensee shall identify the 

firearm to be transferred by listing on 

the Form 4473 the name of the 

manufacturer, the name of the importer 

(if any), the type, model, caliber or 

gauge, and the serial number (including 

any associated license number either as 

a prefix, or if remanufactured or 

imported, separated by a semicolon) of 

the firearm. Where no manufacturer 

name has been identified on a privately 

made firearm, the words ‘‘privately 

made firearm’’ (or abbreviation ‘‘PMF’’) 

shall be recorded as the name of the 

manufacturer. 

* * * * * 

(f) * * * The licensee shall identify 

the firearm to be transferred by listing 

in the Forms 4473 the name of the 

manufacturer, the name of the importer 

(if any), the type, model, caliber or 

gauge, and the serial number of the 

firearm to be transferred. Where no 

manufacturer name has been identified 

on a privately made firearm, the words 

‘‘privately made firearm’’ (or 

abbreviation ‘‘PMF’’) shall be recorded 

as the name of the manufacturer. * * * 

* * * * * 

■ 14. Amend § 478.125 by revising 

paragraphs (e), (f) and (i) to read as 

follows: 

§ 478.125 Record of receipt and 

disposition. 

* * * * * 

(e) Firearms receipt and disposition 

by dealers. Except for adjustment or 

repair of a firearm that is returned to the 

person from whom it was received on 

the same day, each licensed dealer shall 

enter into a record each receipt and 

disposition of firearms. In addition, 

before commencing or continuing a 

firearms business, each licensed dealer 

shall inventory the firearms possessed 

for such business and shall record the 

same in the record required by this 

paragraph. The record required by this 

paragraph shall be maintained in bound 

form in the format prescribed below. 

The purchase or other acquisition of a 

firearm shall, except as provided in 

paragraphs (g) and (i) of this section, be 

recorded not later than the close of the 

next business day following the date of 

such purchase or acquisition. The 

record shall show the date of receipt, 

the name and address or the name and 

license number of the person from 

whom received, the name of the 

manufacturer and importer (if any), the 

model, serial number (including any 

associated license number either as a 

prefix, or if remanufactured or 

imported, separated by a semicolon), 

type, and the caliber or gauge of the 

firearm. In the event the licensee 

records a duplicate entry with the same 

firearm and acquisition information, 

whether to close out an old record book 

or for any other reason, the licensee 

shall record a reference to the date and 

location of the subsequent entry (e.g., 

date of new entry, book name/number, 

page number, and line number) as the 

disposition. The sale or other 

disposition of a firearm shall be 

recorded by the licensed dealer not later 

than seven days following the date of 

such transaction. When such 

disposition is made to a nonlicensee, 

the firearms transaction record, Form 

4473, obtained by the licensed dealer 

shall be retained, until the transaction is 

recorded, separate from the licensee’s 

Form 4473 file and be readily available 

for inspection. When such disposition is 

made to a licensee, the commercial 

record of the transaction shall be 

retained, until the transaction is 

recorded, separate from other 

commercial documents maintained by 

the licensed dealer, and be readily 

available for inspection. The record 

shall show the date of the sale or other 

disposition of each firearm, the name 

and address of the person to whom the 

firearm is transferred, or the name and 

license number of the person to whom 

transferred if such person is a licensee, 

or the firearms transaction record, Form 

4473, transaction number if the licensed 

dealer transferring the firearm 

sequentially numbers the Forms 4473 

and files them numerically. The format 

required for the record of receipt and 

disposition of firearms is as follows: 

TABLE 2 TO PARAGRAPH (e)—FIREARMS DEALER ACQUISITION AND DISPOSITION RECORD

Description of firearm Receipt Disposition 

Manufacturer, importer 

(if any), or 

‘‘privately made firearm’’ 

(PMF) 

Model Serial No. Type Caliber or 

gauge Date 

Name and address of 

nonlicensee; 

or if licensee, name and 

license No. 

Date Name 

Address of nonlicensee; 

license No. of 

licensee; or Form 4473 

transaction No. 

if such forms filed numerically 

(f) Firearms receipt and disposition by 

licensed collectors. (1) Each licensed 

collector shall enter into a record each 

receipt and disposition of firearms 

curios or relics. The record required by 

this paragraph shall be maintained in 

bound form under the format prescribed 

below. The purchase or other 

acquisition of a curio or relic shall, 

except as provided in paragraphs (g) and 

(i) of this section, be recorded not later 

than the close of the next business day 

following the date of such purchase or 

other acquisition. The record shall show 

the date of receipt, the name and 

address or the name and license number 

of the person from whom received, the 

name of the manufacturer and importer 

(if any), the model, serial number 

(including any associated license 

number either as a prefix, or if 

remanufactured or imported, separated 

by a semicolon), type, and the caliber or 

gauge of the firearm curio or relic. In the 

event the licensee records a duplicate 

entry with the same firearm and 

acquisition information, whether to 

close out an old record book or for any 

other reason, the licensee shall record a 

reference to the date and location of the 

subsequent entry (e.g., date of new 

entry, book name/number, page number, 

and line number) as the disposition. The 

sale or other disposition of a curio or 

relic shall be recorded by the licensed 

collector not later than seven days 

following the date of such transaction. 

When such disposition is made to a 

licensee, the commercial record of the 

transaction shall be retained, until the 

transaction is recorded, separate from 

other commercial documents 

maintained by the licensee, and be 

readily available for inspection. The 

record shall show the date of the sale or 

other disposition of each firearm curio 

or relic, the name and address of the 

person to whom the firearm curio or 

relic is transferred, or the name and 

license number of the person to whom 

transferred if such person is a licensee, 


jspears on DSK121TN23PROD with RULES2
24746 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

and the date of birth of the transferee if 

other than a licensee. In addition, the 

licensee shall cause the transferee, if 

other than a licensee, to be identified in 

any manner customarily used in 

commercial transactions (e.g., a driver’s 

license), and note on the record the 

method used. 

(2) The format required for the record 

of receipt and disposition of firearms by 

collectors is as follows: 

TABLE 3 TO PARAGRAPH (f)(2)—FIREARMS COLLECTOR ACQUISITION AND DISPOSITION RECORD

Description of firearm Receipt Disposition 

Manufacturer, 

importer 

(if any), 

or ‘‘privately 

made firearm’’ 

(PMF) 

Model Serial No. Type Caliber or 

gauge Date 

Name and 

address of 

nonlicensee; or 

if 

licensee, name 

and 

license No. 

Date 

Name and 

address of 

nonlicensee; or 

if 

licensee, name 

and 

license No. 

Date of birth if 

nonlicensee 

Driver’s license 

No. or other 

identification if 

nonlicensee 

* * * * * 

(i) Privately made firearms. Except for 

adjustment or repair of a firearm that is 

returned to the person from whom it 

was received on the same day, licensees 

must record each receipt or other 

acquisition (including from a personal 

collection) and disposition (including to 

a personal collection) of a privately 

made firearm as required by this part. 

For purposes of this paragraph, the 

terms ‘‘receipt’’ and ‘‘acquisition’’ shall 

include same-day or on-the-spot 

placement of identifying markings 

unless another licensee is placing the 

markings for, and under the direct 

supervision of, the licensee who 

recorded the acquisition. In that case, 

the licensee placing the markings need 

not record an acquisition from the 

supervising licensee or disposition upon 

return. The serial number need not be 

immediately recorded if the firearm is 

being identified by the licensee, or 

under the licensee’s direct supervision 

with the licensee’s serial number, in 

accordance with § 478.92(a)(2). Once the 

privately made firearm is so identified, 

the licensee shall update the record of 

acquisition entry with the serial 

number, including the license number 

prefix, and shall record its disposition 

in accordance with this section. In this 

part and part 447, where no 

manufacturer name has been identified 

on a privately made firearm (if privately 

made in the United States), the words 

‘‘privately made firearm’’ (or 

abbreviation ‘‘PMF’’) shall be recorded 

as the name of the manufacturer. 

■ 15. In § 478.125a amend paragraph 

(a)(4) by: 

■ a. In the first sentence removing the 

words ‘‘serial number’’ and add in their 

place ‘‘serial number (including any 

associated license number either as a 

prefix, or if remanufactured or 

imported, separated by a semicolon)’’; 

■ b. Adding a new third sentence; and 

■ c. Designating the table as table 1 and 

revising newly designated table 1. 

The addition and revision read as 

follows: 

§ 478.125a Personal firearms collection. 

(a) * * * 

(4) * * * Where no manufacturer 

name has been identified on a privately 

made firearm, the words ‘‘privately 

made firearm’’ (or abbreviation ‘‘PMF’’) 

shall be recorded as the name of the 

manufacturer. * * * 

TABLE 1 TO PARAGRAPH (a)(4)—DISPOSITION RECORD OF PERSONAL FIREARMS

Description of firearm Disposition 

Manufacturer, importer (if 

any), or ‘‘privately made 

firearm’’ (PMF) 

Model Serial No. Type Caliber or 

gauge Date Name and address (business address if licensee) 

Date of birth 

if nonlicensee 

■ 16. Amend § 478.129 by revising 

paragraphs (b), (d) and (e) to read as 

follows: 

§ 478.129 Record retention. 

* * * * * 

(b) Firearms Transaction Record. 

Licensees shall retain each Form 4473 

until business or licensed activity is 

discontinued, either on paper, or in an 

electronic alternate method approved by 

the Director, at the business premises 

readily accessible for inspection under 

this part. Paper forms over 20 years of 

age may be stored at a separate 

warehouse, which shall be considered 

part of the business premises for this 

purpose and subject to inspection under 

this part. Forms 4473 shall be retained 

in the licensee’s records as provided in 

§ 478.124(b), provided that Forms 4473 

with respect to which a sale, delivery, 

or transfer did not take place shall be 

separately retained in alphabetical (by 

name of transferee) or chronological (by 

date of transferee’s certification) order. 

* * * * * 

(d) Records of importation and 

manufacture. Licensees shall maintain 

records of the importation, manufacture, 

or other acquisition of firearms, 

including ATF Forms 6 and 6A as 

required by subpart G of this part, until 

business or licensed activity is 

discontinued. Licensed importers’ 

records and licensed manufacturers’ 

records of the sale or other disposition 

of firearms after December 15, 1968, 

shall be retained until business is 

discontinued, either on paper or in an 

electronic alternate method approved by 

the Director, at the business premises 

readily accessible for inspection under 

this part. Paper records that do not 

contain any open disposition entries 

and with no dispositions recorded 

within 20 years may be stored at a 

separate warehouse, which shall be 

considered part of the business premises 

for this purpose and subject to 

inspection under this part. 

(e) Records of dealers and collectors. 

The records prepared by licensed 

dealers and licensed collectors of the 

sale or other disposition of firearms and 

the corresponding record of receipt of 

such firearms shall be retained until 

business or licensed activity is 

discontinued, either on paper, or in an 

electronic alternate method approved by 

the Director, at the business or 

collection premises readily accessible 

for inspection under this part. Paper 

records that do not contain any open 

disposition entries and with no 

dispositions recorded within 20 years 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24747 

may be stored at a separate warehouse, 

which shall be considered part of the 

business or collection premises for this 

purpose and subject to inspection under 

this part. 

* * * * * 

PART 479—MACHINE GUNS, 

DESTRUCTIVE DEVICES, AND 

CERTAIN OTHER FIREARMS 

■ 17. The authority citation for part 479 

continues to read as follows: 

Authority: 26 U.S.C. 5812; 26 U.S.C. 5822; 

26 U.S.C. 7801; 26 U.S.C. 7805. 

§ 479.11 [Revised] 

■ 18. Amend § 479.11 as follows: 

■ a. Add, in alphabetical order, 

definitions for ‘‘Complete muffler or 

silencer device’’ and ‘‘Complete 

weapon’’; 

■ b. Revise the definition of ‘‘Frame or 

receiver’’; 

■ c. Add the definition of ‘‘Readily’’; 

and 

■ d. Add a sentence at the end of the 

definition of ‘‘Transfer’’. 

The additions and revisions read as 

follows: 

§ 479.11 Meaning of terms. 

* * * * * 

Complete muffler or silencer device. A 

muffler or silencer that contains all 

component parts necessary to function, 

whether or not assembled or operable. 

Complete weapon. A firearm other 

than a muffler or silencer that contains 

all component parts necessary to 

function, whether or not assembled or 

operable. 

* * * * * 

Frame or receiver. The term ‘‘frame or 

receiver’’ shall have the same meaning 

as in § 478.12 of this subchapter. 

* * * * * 

Readily. A process, action, or physical 

state that is fairly or reasonably 

efficient, quick, and easy, but not 

necessarily the most efficient, speediest, 

or easiest process, action, or physical 

state. With respect to the classification 

of firearms, factors relevant in making 

this determination include the 

following: 

(1) Time, i.e., how long it takes to 

finish the process; 

(2) Ease, i.e., how difficult it is to do 

so; 

(3) Expertise, i.e., what knowledge 

and skills are required; 

(4) Equipment, i.e., what tools are 

required; 

(5) Parts availability, i.e., whether 

additional parts are required, and how 

easily they can be obtained; 

(6) Expense, i.e., how much it costs; 

(7) Scope, i.e., the extent to which the 

subject of the process must be changed 

to finish it; and 

(8) Feasibility, i.e., whether the 

process would damage or destroy the 

subject of the process, or cause it to 

malfunction. 

* * * * * 

Transfer. * * * For purposes of this 

part, the term shall not include the 

temporary conveyance of a lawfully 

possessed firearm to a manufacturer or 

dealer qualified under this part for the 

sole purpose of repair, identification, 

evaluation, research, testing, or 

calibration and return to the same 

lawful possessor. 

* * * * * 

■ 19. Revise § 479.102 to read as 

follows: 

§ 479.102 Identification of firearms. 

(a) Identification required. Except as 

otherwise provided in this section, you, 

as a manufacturer, importer, or maker of 

a firearm, must legibly identify the 

firearm as follows: 

(1) Serial number, name, place of 

business. By engraving, casting, 

stamping (impressing), or otherwise 

conspicuously placing or causing to be 

engraved, cast, stamped (impressed) or 

otherwise placed on the frame or 

receiver thereof, an individual serial 

number, in a manner not susceptible of 

being readily obliterated, altered, or 

removed. The serial number must not 

duplicate any serial number placed by 

you on any other firearm. The frame or 

receiver must also be marked with 

either: Your name (or recognized 

abbreviation), and city and State (or 

recognized abbreviation) where you as a 

manufacturer or importer maintain your 

place of business, or in the case of a 

maker, where you made the firearm; or 

if a manufacturer or importer, your 

name (or recognized abbreviation) and 

the serial number that begins with your 

abbreviated Federal firearms license 

number, which is the first three and last 

five digits, as a prefix to a unique 

identification number, followed by a 

hyphen, e.g., ‘‘12345678-[unique 

identification number]’’; and 

(2) Model, caliber or gauge, foreign 

manufacturer, country of manufacture. 

By engraving, casting, stamping 

(impressing), or otherwise 

conspicuously placing or causing to be 

engraved, cast, stamped (impressed) or 

placed on the frame or receiver, or 

barrel or pistol slide (if applicable) 

thereof certain additional information. 

This information must be placed in a 

manner not susceptible of being readily 

obliterated, altered, or removed. The 

additional information shall include: 

(i) The model, if such designation has 

been made; 

(ii) The caliber or gauge; 

(iii) When applicable, the name of the 

foreign manufacturer or maker; and 

(iv) In the case of an imported firearm, 

the name of the country in which it was 

manufactured. For additional 

requirements relating to imported 

firearms, see Customs regulations at 19 

CFR part 134. 

(3) Multi-piece frame or receiver. In 

the case of a multi-piece frame or 

receiver, the modular subpart that is the 

outermost housing or structure designed 

to house, hold, or contain either the 

primary energized component of a 

handgun, breech blocking or sealing 

component of a projectile weapon other 

than a handgun, or internal sound 

reduction component of a firearm 

muffler or firearm silencer, as the case 

may be, shall be the subpart of a multipiece frame or receiver identified in 

accordance with this section. If more 

than one subpart is similarly designed 

to house, hold, or contain such primary 

component (e.g., left and right halves), 

each of those subparts must be 

identified with the same serial number 

and associated licensee information not 

duplicated on any other frame or 

receiver. The identified subpart(s) of a 

complete (assembled or unassembled) 

multi-piece frame or receiver shall not 

be removed and replaced (see § 478.34 

of this subchapter, 18 U.S.C. 922(k), and 

26 U.S.C. 5861(g) and (h)), unless— 

(A) The subpart replacement is not a 

firearm under 26 U.S.C. 5845; 

(B) The subpart replacement is 

identified by the qualified manufacturer 

of the original subpart with the same 

serial number and associated licensee 

information in the manner prescribed by 

this section; and 

(C) The original subpart is destroyed 

under the manufacturer’s control or 

direct supervision prior to such 

placement. 

(4) Frame or receiver, machine gun 

conversion part, or silencer part 

disposed of separately. Each part 

defined as a frame or receiver or 

modular subpart thereof described in 

paragraph (a)(3) of this section, 

machinegun, or firearm muffler or 

firearm silencer that is not a component 

part of a complete weapon or complete 

muffler or silencer device at the time it 

is sold, shipped, or otherwise disposed 

of by you must be identified as required 

by this section with an individual serial 

number not duplicated on any other 

firearm and all additional identifying 

information, except that the model 

designation and caliber or gauge may be 

omitted if that information is unknown 

at the time the part is identified. 


jspears on DSK121TN23PROD with RULES2
24748 Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 

(5) Size and depth of markings. The 

engraving, casting, or stamping 

(impressing) of the serial number and 

additional information must be to a 

minimum depth of .003 inch, and the 

serial number and any associated 

license number in a print size no 

smaller than 1⁄16 inch. The size of the 

serial and license number is measured 

as the distance between the latitudinal 

ends of the character impression 

bottoms (bases). The depth of all 

markings required by this section is 

measured from the flat surface of the 

metal and not the peaks or ridges. 

(6) Period of time to identify firearms. 

You shall identify a complete weapon or 

complete muffler or silencer device no 

later than close of the next business day 

following the date the entire 

manufacturing process has ended for the 

weapon or device, or prior to 

disposition, whichever is sooner. You 

must identify each part or modular 

subpart defined as a machine gun (frame 

or receiver, or conversion part) or 

muffler or silencer that is not a 

component part of a complete weapon 

or complete muffler or silencer device at 

the time it is sold, shipped, or otherwise 

disposed of no later than close of the 

next business day following the date the 

entire manufacturing process has ended 

for the part, or prior to disposition, 

whichever is sooner. For purposes of 

this paragraph, firearms awaiting 

materials, parts, or equipment repair to 

be completed are presumed, absent 

reliable evidence to the contrary, to be 

in the manufacturing process. Importers 

must identify imported firearms within 

the period prescribed in § 478.112 of 

this subchapter. 

(7) Meaning of marking terms. For 

purposes of this section, the term 

‘‘identify’’ means placing marks of 

identification, the terms ‘‘legible’’ and 

‘‘legibly’’ mean that the identification 

markings (including any unique 

identification number) use exclusively 

Roman letters (e.g., A, a, B, b, C, c) and 

Arabic numerals (e.g., 1, 2, 3), or solely 

Arabic numerals, and may include a 

hyphen, and the terms ‘‘conspicuous’’ 

and ‘‘conspicuously’’ mean that the 

identification markings are capable of 

being easily seen with the naked eye 

during normal handling of the firearm 

and are unobstructed by other markings 

when the complete weapon or device is 

assembled. 

(b) Exceptions—(1) Alternate means 

of identification. The Director may 

authorize other means of identification 

to identify firearms upon receipt of a 

letter application or prescribed form 

from you showing that such other 

identification is reasonable and will not 

hinder the effective administration of 

this part. 

(2) Destructive devices. In the case of 

a destructive device, the Director may 

authorize other means of identification 

to identify that weapon upon receipt of 

a letter application or prescribed form 

from you. The application shall show 

that engraving, casting, or stamping 

(impressing) such a weapon as required 

by this section would be dangerous or 

impracticable and that the alternate 

means of identification proposed will 

not hinder the effective administration 

of this part. 

(3) Adoption of identifying markings. 

You may adopt existing markings and 

are not required to mark a serial number 

or other identifying markings previously 

placed on a firearm in accordance with 

this section, as follows: 

(A) Newly manufactured firearms. 

Manufacturers may adopt the serial 

number and other identifying markings 

previously placed on a firearm by 

another manufacturer provided the 

firearm has not been sold, shipped, or 

otherwise disposed of to a person other 

than a qualified manufacturer, importer, 

or dealer, and the serial number adopted 

is not duplicated on any other firearm. 

(B) Remanufactured or imported 

firearms. Manufacturers and importers 

may adopt the serial number or other 

identifying markings previously placed 

on a firearm that otherwise meets the 

requirements of this section that has 

been sold, shipped, or otherwise 

disposed of to a person other than a 

licensee provided that, within the 

period and in the manner herein 

prescribed, the manufacturer or 

importer legibly and conspicuously 

places, or causes to be placed, on the 

frame or receiver either: Their name (or 

recognized abbreviation), and city and 

State (or recognized abbreviation) where 

they maintain their place of business; or 

their name (or recognized abbreviation) 

and abbreviated Federal firearms license 

number, which is the first three and last 

five digits, individually (i.e., not as a 

prefix to the serial number adopted) 

after the letters ‘‘FFL’’, in the following 

format: ‘‘FFL12345678’’. The serial 

number adopted must not duplicate any 

serial number adopted or placed on any 

other firearm, except that if an importer 

receives two or more firearms with the 

same foreign manufacturer’s serial 

number, the importer may adopt the 

serial number by adding letters or 

numbers to that serial number, and may 

include a hyphen. 

(C) Manufacturers performing 

gunsmithing services. Manufacturers 

may adopt the serial number or other 

identifying markings previously placed 

on a firearm by a qualified 

manufacturer, importer, or dealer, 

provided the manufacturer is 

performing services as a gunsmith (as 

defined in § 478.11 of this subchapter) 

on existing firearms not for sale or 

distribution. 

(4)(i) Firearm muffler or silencer parts 

transferred between qualified 

manufacturers for further manufacture 

or to complete new devices. 

Manufacturers qualified under this part 

may transfer a part defined as a muffler 

or silencer to another qualified 

manufacturer without immediately 

identifying or registering such part 

provided that it is for further 

manufacture (i.e., machining, coating, 

etc.) or manufacturing a complete 

muffler or silencer device. Once the new 

device with such part is completed, the 

manufacturer who completes the device 

shall identify and register it in the 

manner and within the period specified 

in this part for a complete muffler or 

silencer device. 

(ii) Firearm muffler or silencer 

replacement parts transferred to 

qualified manufacturers or dealers to 

repair existing devices. Manufacturers 

qualified under this part may transfer a 

replacement part defined as a muffler or 

silencer other than a frame or receiver 

to a qualified manufacturer or dealer 

without identifying or registering such 

part provided that it is for repairing a 

complete muffler or silencer device that 

was previously identified and registered 

in accordance with this part and part 

478. 

(5) Frames or receivers designed 

before August 24, 2022. Manufacturers 

and importers may continue to identify 

the same component of a firearm 

defined as a frame or receiver as it 

existed before August 24, 2022 with the 

same information required to be marked 

by paragraphs (a)(1) and (a)(2) of this 

section that were in effect prior to that 

date, and any rules necessary to ensure 

such identification shall remain 

effective for that purpose. Any frame or 

receiver with a new design 

manufactured after August 24, 2022 

must be marked with the identifying 

information and within the period 

prescribed by this section. For purposes 

of this paragraph, the term ‘‘new 

design’’ means that the design of the 

existing frame or receiver has been 

functionally modified or altered, as 

distinguished from performing a 

cosmetic process that adds to or changes 

the decoration of the frame or receiver 

(e.g., painting or engraving), or by 

adding or replacing stocks, barrels, or 

accessories to the frame or receiver. 

(c) Voluntary classification of 

firearms. The Director may issue a 

determination (classification) to a 


jspears on DSK121TN23PROD with RULES2
Federal Register / Vol. 87, No. 80 / Tuesday, April 26, 2022 / Rules and Regulations 24749 

person whether an item, including a kit, 

is a firearm as defined in this part upon 

receipt of a written request or form 

prescribed by the Director. Each such 

voluntary request or form submitted 

shall be executed under the penalties of 

perjury with a complete and accurate 

description of the item or kit, the name 

and address of the manufacturer or 

importer thereof, and a sample of such 

item or kit for examination. A firearm 

sample must include all accessories and 

attachments relevant to such 

classification as each classification is 

limited to the firearm in the 

configuration submitted. Each request 

for classification of a partially complete, 

disassembled, or nonfunctional item or 

kit must contain any associated 

templates, jigs, molds, equipment, or 

tools that are made available by the 

seller or distributor of the item or kit to 

the purchaser or recipient of the item or 

kit, and any instructions, guides, or 

marketing materials if they will be made 

available by the seller or distributor 

with the item or kit. Upon completion 

of the examination, the Director may 

return the sample to the person who 

made the request unless a determination 

is made that return of the sample would 

be or place the person in violation of 

law. Except for the classification of a 

specific component as the frame or 

receiver of a particular weapon, a 

determination made by the Director 

under this paragraph shall not be 

deemed by any person to be applicable 

to or authoritative with respect to any 

other sample, design, model, or 

configuration. 

§ 479.103 [Amended] 

■ 20. In § 479.103, at the beginning of 

the third sentence, remove the word 

‘‘All’’ and add in its place ‘‘Except as 

provided in § 479.102(b)(4), all’’. 

Merrick B. Garland, 

Attorney General. 

[FR Doc. 2022–08026 Filed 4–25–22; 8:45 am] 

BILLING CODE 4410–FY–P 


jspears on DSK121TN23PROD with RULES2