Court Opinion

ID: 9412913
Source: CourtListenerOpinion
Date Created: 2023-08-01 22:00:41.089012+00
Date Added: 2024-06-11T16:41:32.303023
License: Public Domain

Case: 23-10319     Document: 00516842296          Page: 1     Date Filed: 08/01/2023

           United States Court of Appeals
                for the Fifth Circuit
                                                                       United States Court of Appeals
                                                                                Fifth Circuit

                                          FILED
                                ____________
                                                                         August 1, 2023
                                  No. 23-10319                           Lyle W. Cayce
                                ____________                                  Clerk

   William T. Mock; Christopher Lewis; Firearms Policy
   Coalition, Incorporated, a nonprofit corporation;
   Maxim Defense Industries, L.L.C.,

                                                            Plaintiffs—Appellants,

                                       versus

   Merrick Garland, U.S. Attorney General,
   in his official capacity as Attorney General of the United States;
   United States Department of Justice;
   Bureau of Alcohol, Tobacco, Firearms, and Explosives;
   Steven Dettelbach, in his official capacity
    as the Director of the Bureau of Alcohol, Tobacco, Firearms and Explosives,

                                           Defendants—Appellees.
                  ______________________________

                  Appeal from the United States District Court
                      for the Northern District of Texas
                            USDC No. 4:23-CV-95
                  ______________________________

   Before Smith, Higginson, and Willett, Circuit Judges.
   Jerry E. Smith, Circuit Judge:
          The National Firearms Act of 1934 (“NFA”) and the Gun Control
   Act of 1968 (“GCA”) are two of the primary means of federal arms regula-
   tion and licensure. To that end, the statutes impose heightened, and at times,
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                                        No. 23-10319

   onerous requirements on manufacturing, selling, and transferring certain
   firearms, including short-barreled rifles (“SBRs”). Pistols and handguns are
   not subject to those extra requirements.
           In 2012, a federal firearms licensee (“FFL”) submitted a “stabilizing
   brace” for review to the Bureau of Alcohol, Tobacco, Firearms and Explo-
   sives (“ATF”) and asked whether that stabilizing brace, when attached to a
   pistol, transformed the pistol into a rifle and thus an SBR. The stabilizing
   brace was intended to attach to the forearm and, according to the licensee, to
   permit disabled and weaker persons to fire pistols more easily. Although the
   brace also could be used to shoulder the weapon, the ATF initially indicated
   that the brace did not transform the pistol into a rifle. Now, a decade later,
   the use of stabilizing braces and braced pistols has dramatically increased.
           So, in 2021, the ATF issued a Proposed Rule 1 indicating that the
   agency would use a point system to classify a firearm with a stabilizing brace
   as either a braced pistol or a rifle. After a comment period, during which the
   agency received hundreds of thousands of negative comments, the ATF pub-
   lished the Final Rule. 2
           The Final Rule scrapped the points-based approach of the Proposed
   Rule and, instead, instituted a six-factor balancing test considering every-
   thing from the weight of the firearm with the stabilizing brace attached to the
   prevalence of Youtubers’ demonstrating the likely use of the weapon.
           The Final Rule went into effect on January 31, 2023, but the ATF
   allowed a grace period of four months, which ended on May 31, 2023, giving

           _____________________
           1
            Factoring Criteria for Firearms with Attached “Stabilizing Braces,” 86 Fed. Reg.
   30826 (June 10, 2021) (“Proposed Rule”).
           2
            Factoring Criteria for Firearms with Attached “Stabilizing Braces,” 88 Fed. Reg.
   6478 (Jan. 31, 2023) (“Final Rule”).

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   owners of weapons now considered SBRs multiple options for compliance,
   including registration under the NFA, before criminal penalties would take
   effect.
             These plaintiffs sued for injunctive relief, alleging various statutory
   deficiencies with the process and substance of the Final Rule. They also
   brought constitutional challenges. The district court denied injunctive relief,
   and after it did not rule expeditiously on a motion for an injunction pending
   appeal, this court enjoined enforcement of the Final Rule against the named
   plaintiffs. Plaintiffs now request that we extend that interim relief.
             We reverse the denial of an injunction because plaintiffs will likely
   succeed on the merits of their Administrative Procedure Act (“APA”) chal-
   lenge. We remand with instruction to adjudicate the remainder of the
   preliminary-injunction factors and determine the scope of any relief.

                                             I.
                                             A.
             As stated, this suit is a challenge to the Final Rule, which announces
   when a device marketed as a stabilizing brace turns a pistol or handgun into a
   rifle. In most cases, such a weapon would subsequently be characterized as a
   short-barreled rifle. But examining the Final Rule, as well as the challenge to
   it, requires reviewing the text and history of the NFA and the GCA. 3
             The NFA applies to “firearms.” 26 U.S.C. § 5861. “Firearms” is a
   term of art—one that is both highly under- and over-inclusive (as compared
   to the word’s ordinary meaning today). For instance, the NFA’s definition

             _____________________
             3
            The Attorney General is authorized to administer and enforce the GCA and the
   NFA. 26 U.S.C. §§ 7801(a)(2)(A), 7805(a); 18 U.S.C. § 926(a). That authority was subse-
   quently delegated to the ATF, which promulgates the challenged rule per those Acts.
   28 C.F.R. § 0.130.

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   of “firearm” does not include pistols—but it does include both “silencer[s]”
   and “poison gas.” See id. § 5845(a), (e), (f). That is because the NFA was
   designed to target “gangster-type weapons” that are “especially dangerous
   and unusual.” 4 Final Rule at 6482.
          Because of this, NFA “firearms” are extensively regulated. And
   SBRs are regulated because an NFA “firearm” includes
          [A] a rifle having a barrel or barrels of less than 16 inches in
          length; . . . a weapon made from a rifle if such weapon as mod-
          ified has an overall length of less than 26 inches or a barrel or
          barrels of less than 16 inches in length; . . . any other weapon,
          as defined in subsection (e); . . . .
          ...
          (e) . . . The term “any other weapon” . . . shall not include a
          pistol or a revolver having a rifled bore . . . .
   26 U.S.C. § 5845(a), (e). Although the NFA does not define a “pistol,” it
   does define a “rifle”:
          The term “rifle” means a weapon designed or redesigned, made
          or remade, and intended to be fired from the shoulder and designed
          or redesigned and made or remade to use the energy of the ex-
          plosive in a fixed cartridge to fire only a single projectile
          through a rifled bore for each single pull of the trigger, and shall
          include any such weapon which may be readily restored to fire
          a fixed cartridge.
   Id. § 5845(c) (emphasis added). Putting all of that together, a weapon is a
   “rifle”—that is, either an ordinary rifle (which is not an NFA “firearm”) or
   a short-barreled rifle (which is)—only if it is “designed,” “made,” and “in-
   tended to be fired from the shoulder.” A weapon that fails any one of those

          _____________________
          4
            To that end, the NFA’s definition of “firearm” also includes machineguns and
   short-barreled shotguns.

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   criteria is neither an ordinary rifle nor a short-barreled rifle. Ergo, a weapon
   not meeting the criteria is not a “firearm” under the NFA. A rifle is different
   from an SBR because of the length of the barrel. And the text also states that
   a “pistol” is not an NFA firearm. Nevertheless, the NFA does not define
   “pistol” or explain how to distinguish a pistol from an SBR.
           Enter the GCA, which supplements and is much broader than the
   NFA. The GCA’s definition of “firearm” includes “any weapon . . . de-
   signed . . . to expel a projectile by the action of an explosive.” 18 U.S.C.
   § 921(a)(3). In other words, the GCA’s definition includes all “firearms”—
   in both the NFA’s specialized use of that word and the ordinary-meaning use.
   The GCA also prohibits certain persons from possessing firearms, see, e.g.,
   id. § 922(g)(1), and, as relevant here, establishes requirements for FFLs who
   wish to sell an SBR, id. § 922(a)(4), (b)(4).
           The definition of “rifle” is essentially identical under the NFA and
   the GCA. See 18 U.S.C. § 921(a)(7); 26 U.S.C. § 5845(c). Similarly, the def-
   initions of an SBR roughly track in both statutes, although the GCA, unlike
   the NFA, expressly defines the term. Compare 18 U.S.C. § 921(a)(8), with
   26 U.S.C. § 5845(a)(3)–(4).
           The GCA further defines a “handgun” as “a firearm which has a
   short stock and is designed to be held and fired by the use of a single hand”
   and “any combination of parts from which a firearm described [before] can
   be assembled.” 18 U.S.C. § 921(a)(30). Per regulations providing for ATF’s
   implementation of the NFA, the term “handgun” includes pistols and revol-
   vers. 27 C.F.R. §§ 478.11, 479.11. 5

           _____________________
           5
              A pistol is a “weapon originally designed, made, and intended to fire a projectile
   (bullet) from one or more barrels when held in one hand, and having: [1] a chamber(s) as
   an integral part(s) of, or permanently aligned with, the bore(s); and [2] a short stock
   designed to be gripped by one hand and at an angle to and extending below the line of the

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           So the main difference between rifles and handguns is the shoulder
   stock. A handgun, intended to be fired with one hand, is statutorily required
   to have a short stock and functionally does not need a longer one for recoil
   management or aim. 6 Yet that statutory emphasis on a stock leads to some
   odd results: An AR-style rifle with a barrel shorter than 16 inches is subject
   to the restrictions of the NFA, while an identical AR-style pistol with similar
   dimensions but missing a shoulder stock is not. 7
           That distinction is important. NFA-regulated firearms require regis-
   tration in the National Firearms Registration and Transfer Record, see
   26 U.S.C. § 5841(a), and are subject to stringent restrictions and require-
   ments. NFA-regulated firearms may not be possessed, made, or transferred
   without the authorization of the Attorney General. Id. §§ 5812, 5822. The
   ATF’s authorization is also required before crossing state lines with an NFA
   weapon. 18 U.S.C. § 922(a)(4); 27 C.F.R. § 478.28. 8

           _____________________
   bore(s).” 27 C.F.R. § 478.11. A revolver is a “projectile weapon, of the pistol type, having
   a breechloading chambered cylinder so arranged that the cocking of the hammer or move-
   ment of the trigger rotates it and brings the next cartridge in line with the barrel for firing.”
   Id. The relevant firearms are primarily pistols, not revolvers, so we use the terms
   “handgun” and “pistol” more or less interchangeably.
           6
            Generally speaking, most pistols are actually fired with two hands, with the dom-
   inant hand gripping the pistol itself and the supporting hand gripping on top of the dom-
   inant hand.
           7
              “AR” stands for “ArmaLite Rifle” (named after the original developer), and
   AR-15 rifles are rifles based on the design of the original AR-15 military rifle. AR-pistols
   are pistol-length versions of the rifle without a stock. See Types of Firearms, U.S. Con-
   cealed Carry Ass’n,
   https://www.usconcealedcarry.com/resources/terminology/types-of-firearms/ (last
   visited July 7, 2023).
           8
             Although state-by-state bans on specific NFA weapons vary greatly, numerous
   states ban, or functionally ban, all SBRs, even if the NFA’s requirements are followed. See,
   e.g., What NFA Firearms Are Permitted by Each State?, Nat’l Gun Trusts (Aug. 8,
   2018), https://www.nationalguntrusts.com/blogs/nfa-gun-trust-atf-information-

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           Importers, manufacturers, and dealers of SBRs must register with the
   ATF, must pay a special occupation tax annually, and must register any SBR
   they manufacture. See 26 U.S.C. §§ 5801–02; 5841(c). Finally, when pur-
   chased by individuals, most NFA-regulated firearms, including SBRs, are
   subject to a $200 transfer tax stamp. Id. § 5811; 27 C.F.R. § 479.11. Although
   that financial burden is not particularly onerous today, 9 in 1934, when the
   NFA was enacted, the tax was explicitly intended to tax these weapons out
   of existence. 10 In today’s dollars, $200 in 1934 is approximately $4,500. 11

           _____________________
   database-blog/nfa-items-permitted-by-state.
           9
              A more burdensome issue today may be the time it takes to register a firearm
   under the NFA. In comments on the Proposed Rule, commentators asserted that regis-
   tration often takes many months to a year. Final Rule at 6558. The ATF’s response was
   less than reassuring, merely noting that “NFA processing times continue to decline as
   efficiencies and technology improve.” Id. at 6559. Named plaintiff Christopher Lewis
   specifically mentioned the long delays in his declaration:
              I have specific plans to purchase at least one additional braced pistol
           within the next three to four months, so long as such purchase would not
           subject me to any civil or criminal fines or penalties and could be purchased
           without submitting to the heightened requirements of the NFA, including
           but not limited to . . . the delays imposed by the ATF and other federal
           agencies in administering the NFA.
           10
             As the ATF itself avers, the purpose of the NFA was to “curtail, if not prohibit,
   transactions in NFA firearms . . . . The $200 making and transfer taxes on most NFA
   firearms were considered quite severe and adequate to carry out Congress’ purpose to
   discourage or eliminate transactions in these firearms.” National Firearms Act, ATF
   (Apr. 7, 2020), https://www.atf.gov/rules-and-regulations/national-firearms-act.
           11
               CPI Inflation Calculator, U.S. Bureau of Lab. Stats.,
   https://www.bls.gov/data/inflation_calculator.htm. The tax was set at the approximate
   market price of a machine gun in 1934. See National Firearms Act: Hearing on H.R. 9066
   Before the H. Comm. on Ways & Means, 73d Cong. 12 (1934) (statement of Homer S.
   Cummings, Att’y Gen. of the United States).
           Inflation adjustment also does not capture the severity of the tax. The tax was on
   a per-weapon basis, and in 1940, the average citizen earned only $1,368 a year. See Diane
   Petro, Brother, Can You Spare a Dime? The 1940 Census: Employment and Income, Pro-
   logue Mag., Spring 2012,

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           This especially restrictive regime resulted from panic over gangster-
   related violence and thus was instituted to regulate “weapons likely to be
   used for criminal purposes.” United States v. Thompson/Ctr. Arms Co.,
   504 U.S. 505, 517 (1992) (plurality opinion). Attorney General Homer Cum-
   mings testified,
               A sawed-off shotgun is one of the most dangerous and
           deadly weapons. A machine gun, of course, ought never to be
           in the hands of any private individual. There is not the slightest
           excuse for it, not the least in the world, and we must, if we are
           going to be successful in this effort to suppress crime in
           America, take these machine guns out of the hands of the crim-
           inal class.
   National Firearms Act: Hearings on H.R. 9066 Before the H. Comm. on Ways &
   Means, 73d Cong. 6 (1934). Although not the focus of the Attorney General’s
   comment, sawed-off shotguns were particularly valued for their ability to be
   easily concealed and to unleash devastating damage at short range. 12
           No one was under any misconception that gangsters would obey the
   strictures of the NFA. Indeed, Attorney General Cummings expounded, “I
   do not expect criminals to comply with this law; I do not expect the under-
   world to be going around giving their fingerprints and getting permits to carry
   these weapons, but I want to be in a position . . . to convict [them] because

           _____________________
   https://www.archives.gov/publications/prologue/2012/spring/1940.html.
           12
              As the ATF asserts, the NFA was a “direct response to gang violence” and
   accordingly “imposed criminal, regulatory and tax requirements on weapons favored by
   gangsters: machine guns, silencers and sawed-off shotguns.” National Firearms Act, 1934,
   ATF (Sept. 28, 2016), https://www.atf.gov/our-history/timeline/national-firearms-act-
   1934; see also Brian L. Frye, The Peculiar Story of United States v. Miller, 3 N.Y.U. J.L. &
   Liberty 48, 67 (2008) (quoting a New York Times article from 1939 noting that the
   “favorite arm” of “bank robbers, gangsters and other criminals” was the sawed-off
   shotgun.).

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   [they have] not complied.” 13
          Given that focus on “public safety,” Congress may have believed that
   “a[ny] long gun with a shortened barrel is both dangerous, because its con-
   cealability fosters its use in illicit activity, and unusual, because of its height-
   ened capability to cause damage.” United States v. Cox, 906 F.3d 1170, 1185
   (10th Cir. 2018) (cleaned up). Accordingly, the initial draft of the NFA
   would have regulated a “pistol, revolver, shotgun having a barrel less than
   sixteen inches in length, or any other firearm capable of being concealed on
   the person, a muffler or silencer therefor, or a machine gun.” 14
          But that was not the version that Congress passed. Instead, the final
   text of the NFA specifically exempts “a pistol or a revolver having a rifled
   bore” from its coverage. 26 U.S.C. § 5845(e). And when Congress enacted
   the GCA 30 years later to expand federal firearms regulation, the statute
   defined handguns but did not include any additional restrictions on them.
          And again, those statutory restrictions have teeth: Failure to comply
   with the requirements of the NFA and GCA carries severe consequences.
   Violating the GCA exposes one to criminal penalties, including fines and a
   maximum of five years’ imprisonment. 18 U.S.C. § 924(a)(1). Violating the
   NFA carries the potential for ten years’ imprisonment, 26 U.S.C. § 5871,
   seizure and forfeiture of the firearm, id. § 5872, an assessment of tax liabili-
   ties, 27 C.F.R. § 479.191, and a fine up to $250,000 for an individual and
   $500,000 for an organization. 18 U.S.C. § 3571(b)–(c). As failure to comply
   can also be a felony, a violation may also lead to a lifetime ban on ownership
   of firearms. See 18 U.S.C. § 922(g)(1).

          _____________________
          13
            National Firearms Act: Hearings on H.R. 9066 Before the H. Comm. on Ways &
   Means, 73d Cong. 22 (1934).
          14
               Id. at 1.

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                                              B.
           Consequently, there are immense incentives not to own an SBR but
   instead to have a non-NFA-regulated pistol. Enter the stabilizing brace.
   Otherwise known as a pistol brace, it is a device attached to the rearward part
   of a handgun. Though braces work in different ways, the general concept is
   that they attach to or support the forearm in some way, either by straps or
   another mechanism, and easily allow safe and comfortable pistol-firing with
   one hand.
           In 2012, the first stabilizing brace was submitted to the ATF for
   review. The applicant asked whether the attachment of that device would
   change the pistol’s classification under firearm laws. 15 The applicant stated
   that the brace was designed so that disabled persons could fire heavy pistols
   more safely and comfortably. 16 The ATF examined the sample and con-
   cluded that the submitted brace did “not convert that weapon to be fired
   from the shoulder and would not alter the classification of a pistol or other
   firearm.” Final Rule at 6479.
           Post-submission, these styles of braces increased in popularity, and
   the ATF avers that over the past decade, many of them were being used to
   fire heavy pistols from the shoulder without using the features of the brace.
   See id. Still, ATF regulations defining braces and the legality of their uses
           _____________________
           15
               The ATF’s Firearms and Ammunition Technology Division (“FATD”) deter-
   mines whether a firearm is regulated under either the GCA or the NFA. Because the
   FATD is part of ATF, we, for simplicity, attribute FATD decisions and letters to the ATF.
   See How Do I Send in a Firearm or Ammunition to FATD for Classification?, ATF (May 26,
   2020),       https://www.atf.gov/firearms/qa/how-do-i-send-firearm-or-ammunition-fatd-
   classification.
           16
             See, e.g., About Us, SB Tactical,
   https://www.sb-tactical.com/about/company/ ; see also Letter for John Spencer, Chief,
   Firearms Technology Branch, ATF, from Alex Bosco, NST Global (Nov. 8, 2012); Final
   Rule at 6560.

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   have not been a model of clarity.
            In March 2014, for example, the ATF posited that although it clas-
   sifies weapons “based on their physical design characteristics . . . [and]
   usage/functionality . . . does influence the intended design, it is not the sole
   criterion for determining the [weapon’s classification].” Letter from ATF
   #2014-301737 (Mar. 5, 2014). The ATF explicitly claimed that it does not
   “classify weapons based on how an individual uses a weapon.” Id. As a
   result, an individual’s improperly firing a braced pistol from the shoulder did
   not reclassify the pistol as a short-barreled rifle. Id.
            Then in October of that year, the ATF backtracked and asserted that
   subjective use, instead of design criteria, may change a weapon’s classifi-
   cation. Letter from ATF #2014-302492 (Oct. 28, 2014). Still, by December
   of that year, the ATF approved devices such as the Shockwave Blade Pistol
   stabilizer for use, so long as the device was “used as originally designed and
   NOT used a shoulder stock.” Letter from ATF #2014-302672 (Dec. 15,
   2014).
            In 2015, in response to requests for clarification, the ATF issued an
   Open Letter noting that “[a]ny person who intends to use a handgun stabiliz-
   ing brace as a shoulder stock on a pistol (having a rifled barrel under 16 inches
   in length or a smooth bore firearm with a barrel under 18 inches in length)
   must first file an ATF Form 1 and pay the applicable tax because the resulting
   firearm will be subject to all provisions of the NFA.” 17
            In 2017, the ATF noted that “incidental, sporadic, or situational ‘use’
   of an arm-brace (in its original approved configuration)” did not constitute a
   “redesign” under the NFA and so did not transform the weapon. Letter
            _____________________
            17
              Max M. Kingery, ATF, Open Letter on the Redesign of “Stabilizing Braces”
   (Jan. 16, 2015).

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   from ATF #9000:GM, 5000 (Mar. 27, 2017). “Therefore, an NFA firearm
   has not necessarily been made when the device is not re-configured for use as
   a shoulder stock—even if the attached firearm happens to be fired from the
   shoulder.” Id. As of 2019, the ATF asserted in criminal prosecutions that
   “ATF letters do correctly state that they consider a firearm with a pistol
   brace to not be a rifle under the NFA for purposes of the NFA.” 18
           On the other hand, the ATF asserts that manufacturers were making
   pistol braces so consumers could functionally obtain SBRs without the
   required authorization. 19 Nonetheless, the ATF maintained that stabilizing
   braces were not stocks and that pistols equipped with braces were not short-
   barreled rifles. Exceptions to that general position appeared only when objec-
   tive design features indicated that a weapon was “intended to be fired from
   the shoulder.” 26 U.S.C. § 5845(c). 20 Regardless of their individual merit,
   those determinations proceeded on somewhat of an ad hoc basis, and the
   unifying logic was not always discernable.
           Over this period, the number of pistol braces in America increased
   rapidly, as ATF’s letter rulings approving the braces helped create a thriving

           _____________________
           18
              Sentencing Hr’g Tr. at 38, United States v. Kamali, No. 3:18-cr-00288 (D. Conn.
   Sept. 30, 2019), ECF 110.
           19
               For example, the ATF points to manufacturer SB Tactical’s alleging that its
   braces were “ATF compliant” even though the ATF had evaluated only two of the twenty
   stabilizing braces SB Tactical was selling. See Final Rule at 6492.
           20
              The ATF rejected a pistol brace with rearward ridges on the brace, as the ridges
   “serve[d] no functional purpose in the design of a pistol brace” and instead served only to
   support shoulder fire. See Final Rule at 6488. Similarly, the ATF rejected a weapon design
   that featured both a pistol brace and a forward grip because the forward grip would be useful
   only for two-handed firing, and therefore its presence indicated that the brace’s only pur-
   pose was to support shoulder fire. Id. at 6485. The agency also rejected a “two-strap”
   style brace design whose straps “were not long enough to wrap around the shooter’s arm,”
   as without the straps, the brace’s only purpose was to support shoulder fire. Id. at 6493.

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   market. Thus, “[b]y late 2020,” the ATF had “concluded” that “previous
   . . . classification determinations had led to confusion and there was a need to
   provide clarity to the firearm industry and public on how [the agency] evalu-
   ates firearms equipped with a ‘stabilizing brace.’” Final Rule at 6494. As of
   2023, the ATF estimates there are about 3 million pistol braces in circulation
   (with 7 million at the high end). 21
           Pistol braces also have been used in multiple violent crimes. The ATF
   specifically points to mass shootings in Boulder, Colorado, and Dayton,
   Ohio, where mass shooters killed a combined 19 persons while purportedly
   using a pistol brace as a shoulder stock. Id. at 6508. In the Final Rule, the
   ATF theorizes that SBRs are “dangerous and unusual due to both their
   concealability and their heightened ability to cause damage.” Id. at 6499. In
   support, the ATF notes that since 2015, approximately 63 firearms with sta-
   bilizing braces have been identified in criminal investigations, and there are
   about 105 firearms cases or investigations involving braced weapons. Id. 22
           In response to this regulatory confusion and purported safety threat,
   the ATF published the Proposed Rule through a Notice of Proposed Rule-
   making (“NPRM”) on June 10, 2021. The NPRM proposed to amend the
   Bureau’s regulations “to clarify when a rifle is ‘intended to be fired from the

           _____________________
           21
              ATF, RIN 1140-AA55, Factoring Criteria for Firearms with
   Attached “Stabilizing Braces”: Final Regulatory Impact Analysis
   and       Final       Regulatory       Flexibility      Analysis   18 (2023),
   https://www.atf.gov/rules-and-regulations/docs/undefined/atf2021r-
   08stabilizingbracefrriapdf/download [hereinafter Final Regulatory Impact
   Analysis].
           22
              The ATF suggests that statistic likely undercounts the total number. Still, com-
   pare that number to the annual average of 17,730 people in the United States who are killed
   by guns in homicides (for which Everytown includes shootings by the police). Everystat:
   How does gun violence impact the communities you care about?, Everytown for Gun
   Safety, https://everystat.org/ (last visited July 7, 2023).

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                                     No. 23-10319

   shoulder’” when “equipped with a purported ‘stabilizing brace’” so that the
   ATF could “determine whether these weapons would be considered a . . .
   ‘short-barreled rifle’ under the [GCA] or a . . . ‘firearm’ subject to regulation
   under the [NFA].” Proposed Rule at 30826.
          The NPRM focused on a weapon’s “objective design features.” Id.
   at 30828. “Similar to . . . Form 4590, used to determine if a firearm is ‘sport-
   ing’ for purposes of importation,” the ATF proposed to use a new “Work-
   sheet 4999 to determine if a firearm is designed and intended to be fired from
   the shoulder.” Id. at 30830 (internal quotations added).
          That Worksheet assigned points to various design criteria to indicate
   whether a brace device, in conjunction with the firearm, was intended to be
   shouldered when fired. Id. at 30830–31. If the Worksheet yielded a “total
   point value . . . equal to or greater than 4—in either Section II or III—then
   the firearm, with the attached ‘stabilizing brace,’” would be considered a
   “rifle.” Id. at 30829. And it would very likely be considered a short-barreled
   rifle, too, thereby triggering the NFA and the GCA. The ATF then accepted
   comments until September 8, 2021. Id. at 30826.
          Needless to say, the Proposed Rule was controversial. Comments
   were overwhelmingly negative, with 217,000 of the 237,000 comments made
   in opposition (~92%). See Final Rule at 6497. Approximately 44% of those
   comments were form letters. Id. In contrast, of the 8% of comments in
   support of the NPRM, only 10% were unique, with the rest being form letters.
   Id.
          Although the Worksheet attempted to let the populace know, with
   objective criteria, whether their respective weapons with a brace would be
   classified as rifles, the implementation left much to be desired in practice.
   Just as a short example of the many issues with the Worksheet, determining
   whether an accessory only “[i]ncorporates shoulder stock design feature(s)”

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                                      No. 23-10319

   or instead was “[b]ased on a known shoulder stock design” has some
   inherent level of subjectivity. See Proposed Rule at 30830–31. Additionally,
   some design characteristics were doubly penalized, such as whether the sta-
   bilizing support had a “fin-type” design without an arm strap or whether the
   stabilizing brace was adjustable. See Final Rule at 6530. On the other hand,
   the Proposed Rule did provide specific examples of how an individual could
   grade his firearm: It graded three firearms with attached stabilizing braces
   per Worksheet 4999. And one, an AR-type firearm with an SB-Mini acces-
   sory, passed muster as an approved braced handgun, not a rifle. Proposed
   Rule at 30834–37. The Proposed Rule also had an estimated cost over ten
   years, at a 3% discount rate, of $114.7 million. Id. at 30845.
          Nonetheless, as the ATF recounts in the Final Rule, the Proposed
   Rule was complex and confusing. So about eighteen months later, the ATF
   published the Final Rule. In it, the Worksheet approach was abandoned en-
   tirely. It instead interpreted the NFA’s and GCA’s definitions of “rifle”
   with a two-step process. First, the Final Rule amended the definition of rifle
   under 27 C.F.R. §§ 478.11 and 479.11 to state that the term “desired or re-
   designed, made or remade, and intended to be fired from the shoulder”
   includes
          a weapon that is equipped with an accessory, component, or
          other rearward attachment (e.g., a “stabilizing brace”) that pro-
          vides surface area that allows the weapon to be fired from the shoul-
          der, provided other factors . . . indicate that the weapon is de-
          signed, made, and intended to be fired from the shoulder.
   Final Rule at 6480 (emphasis added). Second, the other factors are
          (1) Whether the weapon has a weight or length consistent with
          the weight or length of similarly designed rifles;
          (2) Whether the weapon has a length of pull, measured from
          the center of the trigger to the center of the shoulder stock or

                                           15
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                                      No. 23-10319

          other rearward accessory, component or attachment (including
          an adjustable or telescoping attachment with the ability to lock
          into various positions along a buffer tube, receiver extension,
          or other attachment method), that is consistent with similarly
          designed rifles;
          (3) Whether the weapon is equipped with sights or a scope with
          eye relief that require the weapon to be fired from the shoulder
          in order to be used as designed;
          (4) Whether the surface area that allows the weapon to be fired
          from the shoulder is created by a buffer tube, receiver exten-
          sion, or any other accessory, component, or other rearward at-
          tachment that is necessary for the cycle of operations;
          (5) The manufacturer’s direct and indirect marketing and pro-
          motional materials indicating the intended use of the weapon;
          and
          (6) Information demonstrating the likely use of the weapon in
          the general community.
   Id. The ATF explains in the Final Rule that “[a]ll of the objective design
   features and factors listed in the rule that indicate the weapon is designed,
   made, and intended to be fired from the shoulder are derived from the NPRM
   and proposed Worksheet 4999.” Id. The agency also emphasizes repeatedly
   that the Final Rule does not ban stabilizing braces or prohibit firearms with a
   stabilizing brace. See e.g., id. at 6480, 6506, 6509.
          The ATF theorized that under this new definition of “rifle,” approx-
   imately 99% of pistols with stabilizing braces would be classified as rifles 23; it
   issued approximately 60 contemporaneous adjudications with the Rule clas-
   sifying various configurations of firearms with stabilizing braces as rifles.24
          _____________________
          23
               See Final Regulatory Impact Analysis, supra note 21, at 21.
          24
          See ATF, Common Weapon Platforms with Attached ‘Stabil-
   izing Brace’ Designs That Are Short-Barreled Rifles (2023),

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                                           No. 23-10319

   No explanations are included for how the ATF came to its conclusion as to
   each weapon and platform. The AR-type firearm with an SB-Mini accessory,
   determined to be a braced pistol under the Proposed Rule, now appears to be
   adjudicated as an SBR under the Final Rule. 25 We also cannot find a single
   given example of a pistol with a stabilizing brace that would constitute an
   NFA-exempt braced pistol. 26
           Regardless, the ATF emphasizes that no stabilizing braces or firearms
   with stabilized braces are banned. Instead, if the clarified definitions indicate
   that a firearm owner now possesses an SBR, the ATF provided five options:
           1. Remove the short barrel and attach a 16-inch or longer rifled
           barrel to the firearm.
           2. Permanently remove and dispose of, or alter, the “stabilizing
           _____________________
   https://www.atf.gov/rules-and-regulations/docs/undefined/bracefinalruleguidance-non-
   commercial/download; ATF, Commercially Available Firearms Equipped
   with a ‘Stabilizing Brace’ That Are Short-Barreled Rifles (2023),
   https://www.atf.gov/rules-and-regulations/docs/undefined/bracefinalruleguidance-
   commerciallypdf/download.
           25
             See ATF, Common Weapon Platforms with Attached ‘Stabil-
   izing Brace’ Designs That Are Short-Barreled Rifles 8–9
   (2023), https://www.atf.gov/rules-and-
   regulations/docs/undefined/bracefinalruleguidance-non-commercial/download.
           26
              The ATF did helpfully note that a design feature that prevents shouldering
   would keep a braced pistol from being classified as a rifle. See Final Rule at 6530 (“A poten-
   tial example of such a feature is a permanently attached protrusion that would dig into a
   shooter’s shoulder should the firearm be fired from the shoulder.”). Presumably, a stabil-
   izing brace with a spike on the end of it may pass muster.
            A recent post states that the “‘other factors’ (including, for example, total weight,
   length-of-pull, and the presence of raised optics) are almost always present in some com-
   bination in heavy pistol set-ups,” so the Rule “has the effect of classifying almost all braced
   pistols as SBRs.” A.W. Geisel, Litigation Highlight: Legal Challenges to ATF Rule on
   Stabilizing Braces, Duke Center for Firearms Law (Mar. 22, 2023),
   https://firearmslaw.duke.edu/2023/03/litigation-highlight-legal-challenges-to-atf-rule-
   on-stabilizing-braces/.

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                                          No. 23-10319

           brace” such that it cannot be reattached.[ 27 28]
           3. Turn the firearm into a local ATF office.
           4. Destroy the firearm.
           5. Register the firearm with the ATF as an SBR per NFA
           requirements.[ 29]

           _____________________
           27
              The ATF notes that removing a stabilizing brace from a firearm originally re-
   ceived as an SBR would produce a weapon “made from a rifle” under the NFA, which
   generally requires registration. The ATF affirms that it would use its discretion not to
   require the registration of any of these firearms so long as the reconfiguration was made by
   May 31, 2023. Final Rule at 6570.
           28
             Plaintiffs observe that ATF Director Steve Dettelbach provided inaccurate tes-
   timony to the House Judiciary Committee on the operation of this portion of the Final
   Rule―to-wit, when questioned by Rep. Thomas Massie about the number of persons who
   had already complied with the Final Rule, Dettelbach stated that he did not have the num-
   ber on hand but could provide it post-hearing. He volunteered that the ATF could not
   count compliance for persons who merely removed a non-compliant brace from a firearm.
   He specifically said,
               We wrote the rule to make it easy to comply with. If somebody just, at
           their home, detaches the weapon from the brace and keeps them apart, uh,
           they do not have to register anything. They can keep the brace. They can
           keep the business end of the gun.
   Oversight of ATF, Hearing Before the H. Judiciary Comm., 118th Cong. (Apr. 26, 2023),
   video available at https://www.youtube.com/watch?v=k91Ugjn9dWE (between 1:54:00–
   1:56:30)).
           That is not a correct description of the operation of this portion of the Rule, which
   the government somewhat acknowledges in its brief. The ATF primarily blames the hear-
   ing format and directs this panel to review a supplemental letter sent from the agency to
   the House Judiciary Committee after the hearing.
           29
              If an owner chose to register his firearm with the ATF before May 31, 2023, the
   ATF would not require him to pay the $200 tax on registration. See Final Rule at 6571.
   The ATF has additionally suggested that an owner who does not believe the statute covers
   his weapon can comply with the Final Rule, pay the tax, and then sue for a refund. Com-
   pliance would require engraving the weapon and placing it on a national registry. See id.
   at 6554, 6563. There is no given process for undoing or recouping those compliance costs.

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                                           No. 23-10319

   Final Rule at 6570.
           Although the Final Rule became effective January 31, 2023, the ATF
   delayed the compliance date to May 31, 2023. Id. at 6478. Anyone possessing
   a braced firearm that the ATF considers, after the Final Rule, to be a rifle,
   and subsequently, a non-NFA-registered firearm, is subject to criminal pun-
   ishment. Id. at 6498.
           The ATF reported it received about 250,000 applications to register
   pistol-brace-equipped firearms before the deadline, for an estimated
   registration-compliance rate (on the high end) of approximately 8%. 30 The
   number of pistol braces removed from weapons or otherwise surrendered to
   the ATF or destroyed is unknown. 31

                                                C.
           Groups of dissatisfied plaintiffs sued to enjoin the Final Rule or post-
   pone its effective date. Though multiple cases are percolating through the
   courts, 32 the present lawsuit has four named plaintiffs.
           William Mock and Christopher Lewis are Texas residents who own at
   least one braced pistol and would purchase more if not for the Final Rule.
   Maxim Defense is a firearms manufacturer and retailer specializing in stabil-
   izing braces and braced pistols. Maxim Defense alleges that the majority of

           _____________________
           30
             Stephen Gutowski, ATF Says a Quarter Million Guns Registered Under Pistol-
   Brace Ban, The Reload (June 2, 2023), https://thereload.com/atf-says-a-quarter-
   million-guns-registered-under-pistol-brace-rule/.
           31
                Id.
           32
              See, e.g., Firearms Regulatory Accountability Coal., Inc. v. Garland, 1:23-cv-00024
   (D.N.D.); Texas v. ATF, 6:23-cv-00013 (S.D. Tex.); Colon v. ATF, 8:23-cv-00223 (M.D.
   Fla.); Second Amendment Found. v. ATF, 3:21-cv-00116 (N.D. Tex.); Britto v. ATF, 2:23-cv-
   00019 (N.D. Tex.); Watterson v. ATF, 4:23-cv-00080 (E.D. Tex.); Nat’l Rifle Ass’n of Am.,
   Inc. v. ATF, 3:23-cv-01471 (N.D. Tex.).

                                                19
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                                     No. 23-10319

   its revenue comes from products that would be subject to the additional
   restrictions of the Final Rule. The Firearms Policy Coalition is a nonprofit
   gun-rights organization whose membership includes individual gun owners,
   licensed manufacturers and retailers, gun ranges, firearms trainers and
   educators, and many others. Mock, Lewis, and Maxim Defense are members
   of the Firearms Policy Coalition.
          As stated, the district court denied a preliminary injunction. First, the
   court held that the ATF likely had statutory authority to issue the Final Rule
   and that the Rule’s criteria do not violate the NFA. The court also rejected
   arguments that it should apply the rule of lenity, or hold the Rule void for
   vagueness, as the Rule “track[s] the statutory definition” and was “compre-
   hensible enough to put a person of ordinary intelligence on notice.”
          Next, the district court reviewed plaintiffs’ APA challenge. The court
   indicated that the Final Rule was interpretative, not legislative. Regardless,
   the court found the Rule did not fail the logical outgrowth test anyway, as the
   Proposed Rule put the public on notice of the subjects, issues, and criteria the
   Final Rule would use and address. Finally, the district court rejected plain-
   tiffs’ constitutional claims, holding that the First Amendment was not vio-
   lated, as the rule did not proscribe speech, nor did it violate the Second
   Amendment. The Second Amendment did not “bar the imposition of tradi-
   tional registration and licensing requirements commonly associated with fire-
   arm ownership,” and plaintiffs’ historical-record evidence was deemed
   inadequate.
          Plaintiffs then moved for an injunction pending appeal, which this
   Court’s motions panel granted while also expediting the appeal. This merits
   panel granted a motion for clarification, explaining that the “plaintiffs in this
   case” covered the customers and members of Maxim Defense and the Fire-
   arms Policy Coalition, “whose interests [those organizations] have repre-

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                                     No. 23-10319

   sented since day one of this litigation.” We additionally clarified that the
   injunction included the individual plaintiffs’ family members. Before this
   merits panel now is the appeal of the order denying a preliminary injunction,
   over which we have appellate jurisdiction per 28 U.S.C. § 1292(a)(1).

                                          II.
          “Although the ultimate decision whether to grant or deny a prelim-
   inary injunction is reviewed only for abuse of discretion, a decision grounded
   in erroneous legal principles is reviewed de novo.” Byrum v. Landreth,
   566 F.3d 442, 445 (5th Cir. 2009) (quoting Women’s Med. Ctr. v. Bell,
   248 F.3d 411, 419 (5th Cir. 2001)). Preliminary injunctions are extraordinary
   remedies, and the moving party must satisfy four factors:
          (1) a substantial likelihood of success on the merits, (2) a sub-
          stantial threat of irreparable injury if the injunction is not
          issued, (3) that the threatened injury if the injunction is denied
          outweighs any harm that will result if the injunction is granted,
          and (4) that the grant of an injunction will not disserve the pub-
          lic interest.
   Id. (quoting Speaks v. Kruse, 445 F.3d 396, 399–400 (5th Cir. 2006)). The
   government’s and the public’s interests merge when the government is a
   party. Nken v. Holder, 556 U.S. 418, 435 (2009).

                                         III.
          No party disputes that the authority to administer and enforce the
   GCA and the NFA is vested in the Attorney General, see 18 U.S.C. § 926(a),
   26 U.S.C. §§ 7801(a)(2)(A), 7805(a), who then delegated that authority to
   the ATF, see 28 C.F.R. § 0.130. Specifically, 28 C.F.R. § 0.130(a) states that
   “the Director of [the ATF] shall: (a) Investigate, administer, and enforce the
   laws related to alcohol, tobacco, firearms, explosives, and arson . . . including
   exercising the functions and powers of the Attorney General under [provi-

                                          21
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                                           No. 23-10319

   sions including the NFA and GCA].”
           Indeed, previous ATF regulations using this authority to classify cer-
   tain weapons and devices as subject to or exempt from federal regulation have
   been recognized consistently in courts nationwide. 33 Yet plaintiffs challenge
   the ATF’s statutory authority to issue the Final Rule. Plaintiffs aver that
   “[t]he Final Rule, which redefines the term ‘rifle’ to encompass what the
   NFA’s plain terms exclude, is an impermissible reading of the plain limits of
   the statute.” Alternatively, plaintiffs urge this court to apply the rule of lenity
   in the context of the ATF’s authority to promulgate rules governing what
   devices fall into the statutory definition of a rifle.
           In Cargill, our en banc court addressed the rule of lenity in the specific
   context of the definition of a “machinegun” and whether a bump stock
   device was covered under it. 57 F.4th at 469–71. We held that “ambiguity
   concerning the ambit of criminal statutes should be resolved in favor of
   lenity.” Id. at 469 (quoting Rewis v. United States, 401 U.S. 808, 812 (1971)).
   Plaintiffs also challenge whether Congress’s delegation of authority to the
   Bureau fails the nondelegation doctrine. 34 Although these claims may be
   colorable, we decline to address them because plaintiffs have a substantial

           _____________________
           33
                See Cargill v. Garland, 57 F.4th 447, 450 (5th Cir. 2023) (en banc), petition for
   cert. filed (Apr. 6, 2023) (No. 22-976); see also Guedes v. ATF, 920 F.3d 1, 6–7 (D.C. Cir.
   2019), judgment entered, 762 F. App’x 7 (D.C. Cir. 2019) (per curiam).
           34
             Though we have never reasoned that those delegations to the ATF violate the
   nondelegation doctrine, there are perhaps serious concerns about the constitutionality of
   the ATF’s interpreting criminal statutes. Although we sidestepped the issue, the en banc
   court pondered whether “[t]he delegation raised serious constitutional concerns by making
   ATF the expositor, executor, and interpreter of criminal laws.” Cargill, 57 F.4th at 471
   (quoting Aposhian v. Wilkinson, 989 F.3d 890, 900 (10th Cir. 2021) (Tymkovich, C.J.,
   dissenting)).

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                                            No. 23-10319

   likelihood of success based on their APA challenge.

                                                 IV.
           We move on to plaintiffs’ claim that the Final Rule violates the APA’s
   procedural and substantive requirements. On that front, plaintiffs establish
   a substantial likelihood of success on the merits. The ATF incorrectly main-
   tains that the Final Rule is merely interpretive, not legislative, and thus not
   subject to the logical-outgrowth test. The Final Rule affects individual rights,
   speaks with the force of law, and significantly implicates private interests.
   Thus, it is legislative in character. Then, because the Final Rule bears almost
   no resemblance in manner or kind to the Proposed Rule, the Final Rule fails
   the logical-outgrowth test and violates the APA.

                                                  A.
           Legislative rules are ones with the “force and effect of law,” 35 while
   interpretive rules “advise the public of the agency’s construction of the
   statutes and rules which it administers. 36 As a result, “[a] court is not re-
   quired to give effect to an interpretive regulation.” Chrysler Corp., 441 U.S.
   at 315 (internal quotations omitted). Only legislative rules must go through
   notice and comment rulemaking under 5 U.S.C. § 553(b)–(c). 37 Perez,
   575 U.S. at 96.
           Most litigation about whether a rule should be properly considered
   legislative or interpretive arises because the agency did not go through the

           _____________________
           35
            Perez v. Mortgage Bankers Ass’n, 575 U.S. 92, 96 (2015) (quoting Chrysler Corp. v.
   Brown, 441 U.S. 281, 302–03 (1979)).
           36
                Id. at 97 (quoting Shalala v. Guernsey Mem’l Hosp., 514 U.S. 87, 99 (1995)).
           37
             Concurrently, “interpretive rules, general statements of policy, or rules of
   agency organization, procedure, or practice” do not have to go through notice and com-
   ment. 5 U.S.C. § 553(b)(A).

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                                           No. 23-10319

   time and expense of notice-and-comment rulemaking. The interesting twist
   here is that the ATF chose to go through notice and comment before promul-
   gating the Final Rule. As a result, whether the Final Rule is legislative or
   interpretive should not be the crux of the APA challenge. Because of plain-
   tiffs’ chosen litigation strategy, however, it is. Plaintiffs have focused on
   whether the Final Rule was a logical outgrowth of the Proposed Rule, see Long
   Island Care at Home, Ltd. v. Coke, 551 U.S. 158, 174 (2007), a requirement
   only for legislative rules. 38 Though the analysis requires reviewing first prin-
   ciples, we agree. The Final Rule is a legislative rule.
           The difference between legislative and interpretive rules has been
   described as “enshrouded in considerable smog.” 39 And our court has not
   exactly spoken with one voice, in a cognizable and consistent manner, about
   how to tell the difference.
           “[I]t is only when the agency seeks to make substantive law that notice
   and comment is required.” 40 But determining when an agency is making

           _____________________
           38
             Even if the Final Rule is properly considered interpretive and not legislative, the
   Rule could have still been tested for procedural regularity and challenged as arbitrary and
   capricious in violation of 5 U.S.C. § 706(2)(a). As the Supreme Court made clear in Perez,
   the public is not without recourse even if an agency attempts to “skirt” the strictures of
   notice and comment with an interpretive rule. See 575 U.S. at 105–06.
           In the present case, such a challenge may have succeeded. But the words “arbi-
   trary and capricious” appear nowhere in plaintiffs’ opening brief, nor does the statutory
   standard of § 706(2)(a). “A party forfeits an argument . . . by failing to adequately brief the
   argument on appeal.” Rollins v. Home Depot USA, 8 F.4th 393, 397 (5th Cir. 2021).
           39
             Am. Mining Cong. v. Mine Safety & Health Admin., 995 F.2d 1106, 1108 (D.C. Cir.
   1993) (quoting Gen. Motors Corp. v. Ruckelshaus, 742 F.2d 1561, 1565 (D.C. Cir. 1984)
   (en banc)).
           40
             Flight Training Int’l, Inc. v. FAA, 58 F.4th 234, 241 n.5 (5th Cir. 2023). Flight
   Training also attempted to clarify the distinction between legislative and substantive rules:
              Legislative rules are sometimes called “substantive rules.” In truth,
           the requirement of notice and comment attaches only to rules that are both

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                                           No. 23-10319

   substantive law is the million-dollar question. 41
           This circuit does not look just to whether a rule “limits discretion or
   uses binding language,” as “[i]f a law is mandatory, it is natural for an
   agency’s restatement of the law to speak in mandatory terms as well.” Flight
   Training, 58 F.4th at 242. On the other hand, legislative rules functionally
   “affect individual rights” and “creat[e] new law.” Davidson v. Glickman,
   169 F.3d 996, 999 (5th Cir. 1999) (internal quotations omitted). Yet, if all the
   rule is doing is interpreting existing law, it is not substantive and thus is not
   legislative in character. Flight Training, 58 F.4th at 241 n.5; see also 5 U.S.C.
   § 553(b)(A).
           This court has not laid out a clear test appropriate to resolve the ques-
   tion. With that in mind, we adopt Judge Ezra’s methodology in Cargill v.
   Barr, 42 in which he largely adopted the D.C. Circuit’s framework, see, e.g.,

           _____________________
           “substantive” and “legislative.” A rule may be called “substantive,” in
           the sense that it is neither procedural nor a mere policy statement, if it is
           binding on the rights and obligations of private persons.
   Id. (citing Texas v. United States, 809 F.3d 134, 171, 176 (5th Cir. 2015), aff’d by an equally
   divided court, 579 U.S. 547 (2016)).
           41
              Neither plaintiffs nor the ATF properly states this circuit’s test. Plaintiffs point
   to the rule this court laid out for policy statements, not interpretive rules, citing Texas v.
   United States, 809 F.3d at 171. On the other hand, the ATF merely notes that the rule is
   purportedly not legislative because “were an individual to be charged with unlawful pos-
   session, a court would determine whether the statute—not the Rule—covered the con-
   duct.” That reading is too restrictive and ignores an inquiry into the rule’s effect. It also
   begs the question—the ATF (or other government entity) would presumably be charging
   an individual with a violation of the statute solely because of the rule.
           42
               See 502 F. Supp. 3d 1163 (W.D. Tex. 2020), aff’d sub nom. Cargill v. Garland,
   20 F.4th 1004 (5th Cir. 2021), rev’d, 57 F.4th 447 (5th Cir. 2023) (en banc), petition for cert.
   filed (Apr. 6, 2023) (No. 22-976). Neither the vacated panel opinion nor the en banc opin-
   ion addressed whether the ATF’s bump stock rule was a legislative or interpretive rule,
   although our en banc court assumed for the sake of argument that it was legislative. See
   Cargill v. Garland, 57 F.4th at 458 n.6.

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   Guedes, 920 F.3d at 17–20, to determine whether the ATF’s bump stock rule
   was legislative or interpretive, see Cargill, 502 F. Supp. 3d at 1185. The test
   has five factors, and we are not bound by an agency’s classification of its
   action. See U.S. Dep’t of Labor v. Kast Metals Corp., 744 F.2d 1145, 1149 (5th
   Cir. 1984).
             The five factors are, first, whether the agency intended to speak with
   the force of law. See Cargill, 502 F. Supp. 3d at 1184 (citing Encino Motorcars,
   LLC v. Navarro, 579 U.S. 211, 215 (2016)). We examine the “language
   actually used by the agency.” Id. (quoting Cmty. Nutrition Inst. v. Young, 818
   F.2d 943, 946 (D.C. Cir. 1987)). Second, we see whether the agency pub-
   lished its rule in the Code of Federal Regulations. Id. (citing Am. Mining
   Cong., 995 F.2d at 1112). Third, we examine whether the agency “explicitly
   invoked its general legislative authority.” Id. (citing Am. Mining Cong.,
   995 F.2d at 1109). Fourth, we note whether the agency claimed Chevron
   deference. 43 Id. (citing Guedes, 920 F.3d at 18–19)). Finally, in the Fifth
   Circuit, courts scrutinize “whether the rule ‘will produce [] significant
   effects on private interests.’” Id. (quoting Gulf Restoration Network v.
   McCarthy, 738 F.3d 227, 236 (5th Cir. 2015) (alteration in original)).
             We can start with the easy factors. The ATF did not invoke Chevron
   deference, cutting against holding that the Final Rule is legislative. Next, the
   Final Rule is published in the Code of Federal Regulations. Publication in
   the C.F.R. is limited to rules “having general applicability and legal effect,”
   44 U.S.C. § 1510, which cuts in favor of the Final Rule’s being legislative.
   Guedes observed that “amendments [to C.F.R. provisions] would be highly
   unusual for a mere interpretive rule.” 920 F.3d at 19. The Final Rule plainly

             _____________________
             43
                  Referring to Chevron, U.S.A., Inc. v. Nat. Res. Def. Council. Inc., 467 U.S. 837
   (1984).

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   amends two C.F.R. provisions (27 C.F.R. §§ 478.11, 479.11). 44 See Final Rule
   at 6480.
           The other three factors are more difficult. First, we must determine
   whether the agency intended to speak with the force of law. In Guedes, the
   D.C. Circuit found it persuasive that the published rule on bump stocks used
   language informing bump stock owners that their devices “will be prohibited”
   upon the rule’s effective date. 920 F.3d at 18 (quoting 83 Fed. Reg. 66514,
   66514). Guedes also keyed in on other important terms, which included that
   the bump stock rule affirmed that “[a]nyone currently in possession of a
   bump-stock-type device is not acting unlawfully unless they fail to relinquish
   or destroy their device after the effective date of this regulation.” Id. (quoting
   83 Fed. Reg. at 66523) (alteration in original) (second emphasis added).
   Additionally, the rule at issue in Guedes “provide[d] specific information
   about acceptable methods of disposal, as well as the timeframe under which
   disposal must be accomplished to avoid violating” the “interpreted” statute.
   Id. (quoting 83 Fed. Reg. at 66530). Finally, the D.C. Circuit also found it
   noteworthy that the rule asserted that only future possession of the bump
   stock devices would be criminalized. Id.
           All of those indicators are present in the Final Rule. Though the
   government carefully designates that the Final Rule does not “ban” stabiliz-
   ing braces, the language of the Final Rule maintains that if an individual has
   an NFA-regulated firearm post-Final Rule ‘clarification,’ he must perform
   one of five options to avoid violating the NFA. See Final Rule at 6572. Simi-
   larly to Guedes, the Final Rule provided information about acceptable dis-

           _____________________
           44
             At oral argument, ATF’s counsel was asked whether he was aware of any other
   time a government agency had published an interpretive rule in the C.F.R. yet still went
   through notice and comment. ATF’s counsel could point only to the bump-stock rule at
   issue in Guedes. Oral Argument at 39:05–40:00.

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   posal methods and gave a timeframe for compliance (by May 31, 2023). See
   id. at 6478, 6572.
           The above shows “prospective, binding language.”                              Cargill,
   502 F. Supp. 3d at 1184. Our conclusion is bolstered by the ATF’s responses
   to commentators alleging that the Proposed Rule was an unconstitutional ex
   post facto law. In response, the ATF suggested that the regulation would not
   “criminalize past conduct.” Instead, the agency, through “enforcement dis-
   cretion,” would give unlicensed individuals 120 days to comply with federal
   law “to avoid civil and criminal penalties,” and the agency was waiving “past
   making and transfer taxes.” Final Rule at 6552–53. Those statements, and
   others throughout the Rule, evince an effort to “directly govern[] the con-
   duct of members of the public, affecting individual rights and obligations.”
   Guedes, 920 F.3d at 18 (quoting Long Island Care, 551 U.S. at 172) (alteration
   in original). 45
           Second, we must determine whether the ATF “explicitly invoked its
   general legislative authority.” Cargill, 502 F. Supp. 3d at 1184 (quoting Am.
   Mining, 995 F.2d at 1112). The answer is yes. The Final Rule cites 26 U.S.C.
   § 7801(a)(2), 28 U.S.C.§ 599A(b)(1), (c)(1), and 28 C.F.R. § 0.130(a)(1)–(2)
   and affirms that those provisions vest “the responsibility for administering
   and enforcing the NFA and GCA” in the Attorney General (and then by del-
   egation to the ATF Director). See Final Rule at 6481. That authority pro-
   vides the ATF the ability to promulgate the Final Rule.
           Finally, we apply the substantial-impact test to see whether the Final
   Rule will “produce . . . significant effects on private interests.” Cargill,
           _____________________
           45
              That prong also cuts against the ATF’s contention that the “relevant portions
   of the Rule are not final agency action . . . [and the Rule] does not itself determine any legal
   rights or impose any legal obligations, as would be required to demonstrate finality,” citing
   Bennett v. Spear, 520 U.S. 154, 178 (1997).

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   502 F. Supp. 3d at 1184 (quoting Gulf Restoration, 783 F.3d at 236). That test
   is the “primary means . . . [to] look beyond the label ‘procedural’ to deter-
   mine whether a rule is of the type Congress thought appropriate for public
   participation.” Texas v. United States, 787 F.3d 733, 765 (5th Cir. 2015)
   (quoting Kast Metals Corp., 744 F.2d at 1153).
          As applied, that test strongly favors determining the Final Rule to be
   legislative, not interpretive. The ATF’s calculations indicate that, using the
   low estimate of 3 million firearms equipped with stabilizing braces, the “com-
   bined private societal and government annualized cost of under this final rule
   would be $245.6 million and $266.9 million” at a 3 percent and 7 percent
   discount rate, respectively. 46 The total cost over ten years is anywhere from
   $1,874,405,737 to $2,095,312,630 (depending on the discount rate). 47 Those
   numbers increase considerably if we review the calculations using the high
   estimate of 7 million firearms equipped with stabilizing braces. 48 In Cargill,
   Judge Ezra found the substantial-impact test was met through a ‘mere’ econ-
   omic impact of $102.5 million. 502 F. Supp. 3d at 1185. Accordingly, “[t]his
   adjustment imposes the type of ‘significant effect[] on private interests’ char-
   acteristic of legislative rules.” Id. (quoting Gulf Restoration, 783 F.3d at 236).
          Inspecting the Final Rule from 10,000 feet, it has significant implica-
   tions for braced-pistol owners. If the government is correct, and the rule is
   only interpretive, millions of Americans were committing a felony the entire
   time they owned a braced pistol. Guedes expounded on the extraordinary
   implications of that determination:
                 The government now characterizes the Rule’s effective
          _____________________
          46
               See Final Regulatory Impact Analysis, supra note 21, at 65–66.
          47
               Id.
          48
               See id. at 66–67.

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           date as merely marking the end of a period of discretionary
           withholding of enforcement, in that the Rule informs the public
           that the Department will not pursue enforcement action
           against individuals who sold or possessed bump stocks prior to
           the effective date. Once again, that is not what the Rule says.
           The government engages in enforcement discretion when it
           voluntarily refrains from prosecuting a person even though he is
           acting unlawfully. The Rule, by contrast, announces that a per-
           son in possession of a bumpstock type device is not acting un-
           lawfully unless they fail to relinquish or destroy their device
           after the effective date of this regulation. That is the language of
           a legislative rule establishing when bump-stock possession will be-
           come unlawful, not an interpretive rule indicating it has always
           been unlawful.
   920 F.3d at 20 (cleaned up) (final emphasis added). Although the govern-
   ment has been more circumspect here, the overall implication and conclusion
   are the same. Before the Final Rule, the ATF would not prosecute an indi-
   vidual for owning a braced pistol. There was no indication that persons or
   organizations acted unlawfully before the Final Rule’s publication by pos-
   sessing or transferring a braced pistol. Post-Final Rule, the government has
   attempted to claim that the stabilizing braces were always unlawful—but that
   is flatly unpersuasive given the history of ATF regulation and action. The
   character of the rule is legislative. 49
           The ATF’s main rebuttal is that “were an individual to be charged
   with unlawful possession, a court would determine whether the statute—not
   the Rule—covered the conduct.” That is too clever by half. We do not look
   at just the prosecutorial effect of the Rule—we scrutinize the Rule as a whole
           _____________________
           49
              The ATF consistently states that it averred “firearms equipped with ‘braces’
   may be short-barreled rifles,” citing Final Rule at 6487. But the ATF often issued letter
   rulings permitting braced pistols to proliferate instead of enforcing the law against persons
   it now, overnight, deems to be potential felons.

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   and determine its effects. 50 In Appalachian Power Co. v. EPA, 208 F.3d 1015
   (D.C. Cir. 2000), the court found that an EPA guidance document was a
   legislative rule despite the document’s denying it was compulsory. The court
   examined the whole document and was struck that “the entire Guidance,
   from beginning to end—except the last paragraph—reads like a ukase. It
   commands, it requires, it orders, it dictates.” Id. at 1023. The same appears
   true here. The factors as a whole indicate that the Final Rule is a legislative
   rule.

                                                 B.
           Because the Final Rule is properly characterized as a legislative rule,
   it must follow the APA’s procedural requirements for notice and comment,
   including providing the public with a meaningful opportunity to comment on
   the proposed rule. See 5 U.S.C. § 553(c). After the required NPRM is pub-
   lished in the Federal Register, with “either the terms or substance of the pro-
   posed rule or a description of the subjects and issues involved,” id.
   § 553(b)(3), “the final rule the agency adopts must be a logical outgrowth of
   the rule proposed,” Long Island Care, 551 U.S. at 174 (cleaned up). If the
   logical-outgrowth requirement is not satisfied, a court must set aside the
   agency action found to be “without observance of procedure required by
   law.” 5 U.S.C. § 706(2)(D).
           In the Fifth Circuit, the logical-outgrowth rule requires the NPRM to
   provide “fair notice” of the eventual Final Rule. Tex. Ass’n of Mfrs. v. U.S.
   Consumer Prod. Safety Comm’n, 989 F.3d 368, 381 (5th Cir. 2012) (citing Long
   Island Care, 551 U.S. at 174). “If interested parties ‘should have anticipated’

           _____________________
           50
             Moreover, as mentioned supra, prosecution will ensue only because of the Final
   Rule. Nor is it likely that any reviewing court would fail to consider the Rule in any criminal
   prosecution.

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   that the change was possible, and thus reasonably should have filed their
   comments on the subject during the notice-and-comment period, then the
   rule is deemed to constitute a logical outgrowth of the proposed rule.” Id. at
   381–82 (quoting Am. Coke & Coal Chems. Inst. v. EPA, 452 F.3d 930, 938
   (D.C. Cir. 2006)).
          An NPRM is not required to “specifically identify every precise pro-
   posal which the agency may ultimately adopt as a final rule.” Chem. Mfrs.
   Ass’n v. EPA, 870 F.2d 177, 203 (5th Cir. 1989) (cleaned up). Instead, an
   NPRM must “adequately frame the subjects for discussion such that the
   affected party should have anticipated the agency’s final course in light of the
   initial notice.” Huawei Techs. USA, Inc. v. FCC, 2 F.4th 421, 447 (5th Cir.
   2021) (cleaned up).
          As plaintiffs persuasively posit, the NPRM and the Final Rule bear
   little resemblance to one another. The Proposed Rule centered entirely on
   Worksheet 4999, which determined, by an extensive point system, whether
   a firearm was a “rifle” under the NFA. See Proposed Rule at 30830–31.
   Although the Worksheet was flawed in many aspects, it focused on the design
   of a firearm with the stabilizing brace and attempted to provide objective
   measurement criteria for whether a particular stabilizing brace was a
   shoulder-fired design that would be subject to the NFA and GCA.
          Unsurprisingly, the comments on the Proposed Rule concentrated on
   implementing Worksheet 4999. See Final Rule at 6510–48. The Worksheet
   was the focal point of the entire Proposed Rule, to the extent that the ATF
   represented that “[t]he ATF Worksheet 4999 is necessary to enforce the law
   consistently.” Proposed Rule at 30829. Nothing in the Proposed Rule put
   the public on notice that the Worksheet would be replaced with a six-factor
   test based on almost entirely subjective criteria. Nor was the public, which
   criticized the subjective nature of the purportedly objective criteria of Work-

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   sheet 4999 and its overbreadth, see, e.g., Final Rule at 6513–14, 6521–22, 6527,
   6529–30, put on notice that not only would the ATF change the criteria, but
   it also would make the criteria so expansive as to subject an estimated 99% of
   stabilizing braces on the market to enhanced regulations 51 and increase the
   economic effect of the Rule by over $100 million. 52
          As the district court found, the logical-outgrowth test requires that the
   proposed rule “fairly apprises interested persons of the subjects and issues
   the agency is considering,” citing Chemical Mfrs. Ass’n, 870 F.2d at 203. But
   merely informing the public, in a generic sense, of the broad subjects and
   issues the Final Rule would address is insufficient. Instead, the Proposed and
   Final Rule must be alike in kind so that commentators could have reasonably
   anticipated the Final Rule.
          Commentators were given the Proposed Rule. They reacted nega-
   tively, piling in almost 217,000 comments of “general dissatisfaction” with
   the use of Worksheet 4999. See Final Rule at 6510, 6513. Nevertheless,
   nowhere in the Proposed Rule did the ATF give notice that it was considering
   getting rid of the Worksheet for a vaguer test. Instead, the “Comments
   Sought” section of the Proposed Rule requested only “additional criteria
   that should be considered” and comments on whether the ATF “selected
   the most appropriate criteria.” Proposed Rule at 30850. Removing all
   objective criteria operates a rug-pull on the public.
          The ATF’s counterarguments are not compelling.                        The Bureau
   primarily avers that the factors in the Final Rule are “derived from the
   NPRM and proposed Worksheet 4999,” citing the Final Rule at 6480.
   Furthermore, the agency alleges that the changes were made because of the
          _____________________
          51
               See Final Regulatory Impact Analysis, supra note 21, at 21.
          52
               Compare Proposed Rule at 30845 tbl.2, with Final Rule at 6573 tbl.2.

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   aforementioned dissatisfaction with the Proposed Rule. But proclaiming
   something to be the case, even in the Federal Register, does not make it so,
   hence why “[a]n agency . . . does not have carte blanche to establish a rule
   contrary to its original proposal simply because it receives suggestions to alter
   it during the comment period.” Chocolate Mfrs. Ass’ n of the U.S. v. Block,
   755 F.2d 1098, 1104 (4th Cir. 1985). Instead, an “[a]gency notice must
   describe the range of alternatives being considered with reasonable
   specificity.” Small Refiner Lead Phase-Down Task Force v. EPA, 705 F.2d 506,
   549 (D.C. Cir. 1983). If comments indicated that the method in the Proposed
   Rule was so unworkable that the entire procedure needed to be replaced, then
   the proper process would be to start the notice-and-comment process again
   and receive public comments on the new test.
          With that in mind, commentators reading the Proposed Rule’s lan-
   guage could not have reasonably foreseen that the Final Rule would replace
   the Worksheet entirely with a more subjective six-factor test. It was indeed
   “reasonably foreseeable” that changes would be made between the NPRM
   and the Final Rule, see Long Island Care, 551 U.S. at 175, but the specific
   changes in the Final Rule, and their scope, were not. In short, the fatal flaw
   is conceptual: Whereas the Worksheet allowed an individual to analyze his
   own weapon and gave each individual an objective basis to disagree with the
   ATF’s determinations, the Final Rule vests the ATF with complete discre-
   tion to use a subjective balancing test to weigh six opaque factors on an invisi-
   ble scale.
          Under the Final Rule, it is nigh impossible for a regular citizen to
   determine what constitutes a braced pistol, and outside of the sixty contem-
   poraneous adjudications that the ATF released, whether a specified braced

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                                           No. 23-10319

   pistol requires NFA registration. 53 Various AR pistols without a recognizable
   “brace” may fall into the strictures of the Final Rule. 54 Such an owner may
   not be on notice that his firearm is subject to criminal penalties without
   registration.
           Nor does the ATF bother to clarify the matter. The agency maintains
   that its six-factor test objectively assesses “design features common to
   rifles.” See Final Rule at 6513. But it simultaneously declares that the objec-
   tive criteria given to assess certain factors “are not themselves determina-
   tive,” see id. at 6518, and that adjudications are made “on a case-by-case
   basis,” id. at 6495.
           Predictably then, the six-part test provides no meaningful clarity about
   what constitutes an impermissible stabilizing brace. The ATF did not pro-
   vide explanations with its contemporaneous adjudications that certain
           _____________________
           53
                See supra note 25.
           54
              The ATF includes a picture of an AR-type pistol with a padded buffer tube as a
   potential example of a pistol not classified as a rifle because the buffer tube is required for
   the cycle of operations. The ATF states that “[a]n AR-type pistol with a standard 6 to 6½
   inch buffer tube may not be designed and intended to be fired from the shoulder even if the
   buffer tube provides surface area that allows the firearm to be shoulder fired because it is
   required for the cycle of operations of the weapon.” ATF, Final Rule 2021R-08F:
   Factoring Criteria for Firearms with Attached “Stabilizing
   Braces” 19 (2023) (emphasis added), https://www.atf.gov/rules-and-
   regulations/docs/undefined/finalrule2021r-08f508pdf/download
            But the ATF is not explicit about when the amount of padding on a required buffer
   tube matters or about whether the AR-type pistol shown would, in fact, be adjudicated as
   not a rifle after looking at all of the other factors (we note that the epistemic modality
   marker “may” is used instead of a verb denoting certainty). From our view, the padding
   on the end of the buffer tube is unnecessary for operation, although the buffer tube itself is.
   But see Final Rule at 6485 (finding that a foam-padded stabilizer tube on a Glock-type pistol
   with an overmold kit was an SBR). So both the AR-pistol and the Glock-type pistol can be
   fired from the shoulder with the padding, and both have “a surface area that allows shoul-
   dering.” Id. at 6529. The ATF merely states that it would analyze other factors in the rule.
   Id. at 6529–30.

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   weapons and platforms with stabilizing braces were SBRs under the Final
   Rule, nor did the ATF provide a single example of a stabilizing brace with a
   handgun that would be permitted under the Final Rule. Nor is the Final Rule
   even logically coextensive with the examples provided in the Proposed Rule.
           For example, it is wholly unclear why the AR-type firearm with an SB-
   Mini accessory, adjudicated as an approved braced handgun in the NPRM,
   see Proposed Rule at 30834–37, is not adjudicated the same way under the
   Final Rule. 55 What is more, the ATF’s bald assertion, in briefing, that “the
   Rule provides clear guidance about particular braced pistol designs that
   include true arm braces for one-handed firing and are therefore not subject to
   the NFA” is supported by no citations to the Final Rule and no examples of
   any designs are identified in the Final Rule.
           Other serious infirmities in the Final Rule that vastly expand its scope
   are unrelated to, and do not correlate with, anything mentioned in the Pro-
   posed Rule. In particular, the requirements involving analysis of third par-
   ties’ actions, such as the “manufacturer’s direct and indirect marketing and
   promotional materials,” and “[i]nformation demonstrating the likely use of
   the weapon in the general community,” Final Rule at 6480, would hold citi-
   zens criminally liable for the actions of others, who are likely unknown, unaf-
   filiated, and uncontrollable by the person being regulated. 56 None of those
   factors was included in the Proposed Rule, and we cannot say “that the ulti-

           _____________________
           55
             See ATF, Common Weapon Platforms with Attached ‘Stabil-
   izing Brace’ Designs That Are Short-Barreled Rifles 8–9
   (2023), https://www.atf.gov/rules-and-
   regulations/docs/undefined/bracefinalruleguidance-non-commercial/download.
           56
              None of those issues would be a problem if the ATF adjudicated stabilizing
   braces systematically, such as by stating that a particular manufacturer’s specific brace was
   impermissible, instead of adjudicating braces on an entirely ad hoc basis. But the ATF
   considered and explicitly rejected that approach. See Final Rule at 6513.

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   mate changes in the proposed rule were in character with the original scheme
   or a logical outgrowth of the notice.” Chocolate Mfrs., 755 F.2d at 1107.
           Nor is the agency correct that “any error would be harmless.” Al-
   though our circuit has held that plaintiffs challenging an agency’s error for
   procedural challenges must “demonstrate prejudice,” City of Arlington v.
   FCC, 668 F.3d 229, 243 (5th Cir. 2012) (cleaned up), aff’d, 569 U.S. 290
   (2013), plaintiffs have easily proven that. As they have illustrated, they could
   not comment on the specifics of the Final Rule, given how vastly different the
   Proposed and Final Rule turned out. As a result, plaintiffs were not on
   notice, 57 nor could they comment on the expanded rule. That is sufficient
   prejudice. 58
           In conclusion, it is relatively straightforward that the Final Rule was
   not a logical outgrowth of the Proposed Rule, and the monumental error was

           _____________________
           57
              This is in direct contrast to City of Arlington, where the FCC did adequately put
   the plaintiffs on notice that the agency was considering changing the proposed rule, nor
   were the FCC’s changes substantially different in kind from what it had proposed previ-
   ously, and what petitioners had a chance to comment on. See 668 F.3d at 235, 244–45.
           58
              The ATF cites City of Waukesha v. EPA, 320 F.3d 228, 246 (D.C. Cir. 2003) (per
   curiam), to support the proposition that plaintiffs would have had to submit additional and
   different comments. That requirement has no Fifth Circuit support, and in any event, the
   plaintiffs have suggested, through briefing, a number of comments they would have liked
   to have made against the Final Rule. Moreover, as City of Waukesha itself declares,
           [T]here are also situations where prejudice need not be shown by petition-
           ers in a notice-and-comment rulemaking challenge, “where the agency has
           entirely failed to comply with notice-and-comment requirements, and the
           agency has offered no persuasive evidence that possible objections to its
           final rules have been given sufficient consideration” . . . . [A] rule re-
           quiring petitioners in all “logical outgrowth” cases to show what addi-
           tional comments they would have submitted had notice been adequate
           would improperly merge the analysis on the merits of whether the final
           rule is a “logical outgrowth” with any applicable prejudice analysis.
   320 F.3d at 246 (quoting Shell Oil Co. v. EPA, 950 F.2d 741, 752 (D.C. Cir. 1991)).

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   prejudicial. The Final Rule therefore must be set aside as unlawful or other-
   wise remanded for appropriate remediation. 59

                                                 V.
           Plaintiffs are likely to succeed on the merits and have thus carried part
   of their burden to obtain a preliminary injunction. The order of the district
   court to the contrary is reversed.
           Plaintiffs must satisfy the other preliminary injunction factors: There
   must be irreparable harm, and the balance of equities and the public interest
   must favor injunctive relief. The district court did not conduct that analysis,
   having erroneously found that the plaintiffs failed on the first factor.
           Although plaintiffs urge this court to conduct this analysis ourselves
   and enter a nationwide injunction, we decline to do so now. For preliminary
   injunctions, “none of the . . . prerequisites has a fixed quantitative value.
   Rather, a sliding scale is utilized, which takes into account the intensity of
   each in a given calculus.” Texas v. Seatrain Int’l, S.A., 518 F.2d 175, 180 (5th
   Cir. 1975). A preliminary injunction is an “extraordinary remedy,” and the
   “burden of persuasion on all . . . requirements” is on the movant party. Big
   Tyme Invs., L.L.C. v. Edwards, 985 F.3d 456, 464 (5th Cir. 2021) (quoting
   Dennis Melancon, Inc., v. City of New Orleans, 703 F.3d 262, 268 (5th Cir.
   2012)). Although plaintiffs succeed on the first factor, the others are yet to
   be determined. 60

           _____________________
           59
               Because plaintiffs are likely to succeed on the merits of their APA challenge, it is
   unnecessary to address their constitutional claims. See, e.g., Braidwood Mgmt., Inc. v EEOC,
   70 F.4th 914, 940 n.60 (5th Cir. 2023). Moreover, because this panel is hearing the case as
   only an appeal from the denial of a preliminary injunction, those difficult questions are
   better left for non-expedited briefing in a plenary proceeding on the merits.
           60
            There is authority that the first factor―likelihood of success on the merits―is the
   most important of the preliminary injunction factors. See Def. Distributed v. United States

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           Given the nature of the remedy and the fact that in this posture, the
   district court has not conducted extensive fact-finding or built a record for
   this court, we remand for a ruling on a preliminary injunction. The paucity
   of the current record on appeal makes it inappropriate for this court to step
   in before the district court has ruled. 61
           Similarly, determining the scope of injunctive relief is better suited to
   the district court in the first instance. “American courts of equity did not
   provide relief beyond the parties to the case . . . [although] an injunction
   could benefit non-parties as long as that benefit was merely incidental.” Feds
   for Med. Freedom v. Biden, 63 F.4th 366, 387 (5th Cir. 2023) (en banc) (cleaned
   up). For that reason, “nationwide injunctions are [not] required or even the
   norm.” Louisiana v. Becerra, 20 F.4th 260, 263 (5th Cir. 2021) (per curiam).
           Still, in certain circumstances, nationwide relief is appropriate and
   may be necessary for the benefit of all parties. In Feds for Medical Freedom,
   for example, the en banc court permitted a nationwide injunction because the
   organization’s membership numbered thousands, and the members were
   scattered nationwide. 63 F.4th at 387–89. In those circumstances, we rea-
   soned that “limiting the relief to only those before [the court] would prove
   unwieldy and would only cause more confusion.” Id. at 388. Moreover,
   injunctions should be crafted to “provide complete relief to the plaintiffs.”
   Califano v. Yamasaki, 442 U.S. 682, 702 (1979).

           _____________________
   Dep’t of State, 838 F.3d 451, 463 (5th Cir. 2016) (Jones, J., dissenting); cf. Tesfamichael v.
   Gonzales, 411 F.3d 169, 176 (5th Cir. 2005) (Smith, J.). Still, even with a strong likelihood
   of success, a district court cannot give the other factors short shrift. See Winter v. Nat. Res.
   Def. Council, 555 U.S. 7, 21–26 (2008).
           61
               See Chavez v. Plan Benefit Servs., Inc., 957 F.3d 542, 547 (5th Cir. 2020)
   (“Appellate judges are not finders of fact, and . . . it’s up to the district judge to find the
   facts.”) (footnote omitted).

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                                           No. 23-10319

           The present case is also not the only one involving a challenge to the
   Final Rule. Multiple judges within this circuit have already issued injunc-
   tions against the Final Rule, following the initial one issued here, enjoining
   enforcement against members of various gun rights organizations. 62 It is
   already uncertain how many persons are now subject to these injunctions or
   how the ATF would enforce the Final Rule against non-enjoined parties.
   There is a need for consistent application of the law, and this court may not
   have all the required facts. Accordingly, the district court is better situated
   to weigh the facts and fashion the most appropriate relief.
                                          * * * * *
           For the foregoing reasons, we REVERSE the order denying a prelim-
   inary injunction and REMAND with instruction to consider that motion
   expeditiously. To ensure relative stability, we MAINTAIN the preliminary
   injunction pending appeal that the motions panel issued on May 23, 2023, as
   clarified by this merits panel on May 26, 2023. 63 This court’s injunction will
   expire 60 days from the date of this decision, or once the district court rules
   on a preliminary injunction, whichever occurs first. We direct the district
   court to rule within 60 days.
           We place no limitation on the matters that the conscientious district
   court may address on remand, and we give no indication of what decisions it
   should reach, regarding a preliminary injunction or any other matter.

           _____________________
           62
             See, e.g., Texas v. ATF, No. 6:23-CV-00013, 2023 WL 3763895 (S.D. Tex.
   May 31, 2023); Order, Second Amend. Found., Inc. v. ATF, No. 3:21-cv-00116 (N.D. Tex.
   May 31, 2023), ECF No. 65.
           63
              See, e.g., In re JPMorgan Chase & Co., 916 F.3d 494, 498 (5th Cir. 2019)
   (Smith, J.) (“We continue the stay of the district court’s . . . order for thirty days to give
   the court full opportunity to reconsider that order.”).

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   Don R. Willett, Circuit Judge, concurring:
          I join the majority’s careful opinion in full measure. I write separately
   because I suspect that the Final Rule would likely fail constitutional muster
   even if it were a logical outgrowth of the worksheet idea that preceded it.
          Rearward attachments, besides making a pistol less concealable,
   improve a pistol’s stability, and thus a user’s accuracy. Accuracy, in turn,
   promotes safety. Even for attachments that convert a pistol into a rifle under
   the statutes, ATF has not identified any historical tradition of requiring
   ordinary citizens to endure a lengthy, costly, and discretionary approval
   process just to use accessories that make an otherwise lawful weapon safer.
   Instead, the NFA tends to regulate weapons that inflict indiscriminate
   destruction: “machinegun[s]”, short-barreled “shotgun[s],” and “smooth
   bore” weapons (and for that matter, “explosive[s]”, “grenade[s]”, and
   “poison gas”). 1 Weapons that begin as rifles, too, are more difficult to keep
   accurate once the barrel starts shrinking.
          In my view, protected Second Amendment “conduct” likely includes
   making common, safety-improving modifications to otherwise lawfully
   bearable arms. 2 Remember: ATF agrees that the weapons here are lawfully
   bearable pistols absent a rearward attachment. Congress might someday try
   to add heavy pistols to the NFA and the GCA, but it hasn’t yet. These pistols
   are therefore lawful. Adding a rearward attachment—whether as a brace or a
   stock—makes the pistol more stable and the user more accurate. I believe
   these distinctions likely have constitutional significance under Bruen.

          _____________________
          1
              26 U.S.C. § 5845.
          2
              New York State Rifle & Pistol Ass’n, Inc. v. Bruen, 142 S. Ct. 2111, 2130 (2022).

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         Still, at this early stage, I agree that the majority’s APA analysis is
   enough for today, even if the constitutional questions may soon return.

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                                         No. 23-10319

   Stephen A. Higginson, Circuit Judge, dissenting:
           Almost ninety years ago, Congress passed the National Firearms Act
   (“NFA”) as a registration regime for uniquely dangerous weapons. By
   congressional delegation, the Bureau of Alcohol, Tobacco, Firearms and
   Explosives (“ATF”) must “take Care” that this legislation is enforced.
   U.S. Const. art. II, § 3. To carry out this responsibility, ATF has tried to
   close a loophole 1 in its enforcement of Congress’s century-old regulation—
   not ban—of particularly dangerous firearms. Judge Reed O’Connor upheld
   ATF’s clarifying rule, concluding that these plaintiffs’ arguments against it
   lacked merit. I would affirm.

           _____________________
           1
              See Factoring Criteria for Firearms With Attached “Stabilizing Braces,” 88 Fed.
   Reg. 6,478, 6,495, 6,497 (Jan. 31, 2023) [hereinafter, “Final Rule”] (citing media
   commentary that the Dayton, Ohio mass shooter’s modified gun “May have Exploited a
   Legal Loophole,” and broadly agreeing with commenters that the proposed role would
   “close the ‘Arm Brace Loophole’” and prevent gun companies from “circumvent[ing] the
   law through the use of ‘braces’”). To illustrate the “Arm Brace Loophole” in the context
   of this case, consider the below photographs taken from the parties’ briefs. The guns on
   the top are equipped with a “stabilizing brace.” The guns on the bottom are equipped with
   a stock. It is undisputed that stocks convert the guns into NFA-regulated short-barreled
   rifles (“SBRs”). It was confirmed at oral argument that one of the individual plaintiffs in
   this case owns the “braced pistol” depicted on the top left.

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                                         I.
          As we have explained before, “[o]nly under extraordinary
   circumstances will we reverse the denial of a preliminary injunction.” Future
   Proof Brands, LLC v. Molson Coors Beverage Co., 982 F.3d 280, 288 (5th Cir.
   2020) (citation omitted). Unlike the majority, I would not reverse Judge
   O’Connor’s determination that the plaintiffs have failed to demonstrate a
   substantial likelihood of success on their claim under the Administrative
   Procedure Act (“APA”). In my view, ATF did not violate the APA’s notice-
   and-comment requirements when it: (i) on June 10, 2021, published a notice
   of proposed rulemaking on “Factoring Criteria for Firearms With Attached
   ‘Stabilizing Braces,’” 86 Fed. Reg. 30,826 (June 10, 2021); (ii) received and
   reviewed over 237,000 comments on that proposal from “individuals,
   lawyers, government officials, and various interest groups,” Final Rule at
   6,497; and (iii) on January 31, 2023, responded to those comments with its
   Final Rule on the subject. Id. at 6,478.
                                         A.
          The plaintiffs’ APA argument is that ATF failed to provide notice and
   invite comment on its Final Rule. This argument gets off the ground only if
   the Final Rule is legislative, rather than interpretive, in nature. This is
   because interpretive rules, like some other types of agency action, are not
   subject to the APA’s notice-and-comment requirements. See 5 U.S.C.
   § 553(b)(A).
          In their fifty-four-page brief, the plaintiffs dedicate a portion of one
   paragraph—spanning about half a page—to the proposition that the Rule is
   legislative rather than interpretive. In that short section, the plaintiffs
   contend that the legislative-interpretive distinction is governed by “two
   criteria” enumerated in our decision in Texas v. United States, 809 F.3d 134,
   171 (5th Cir. 2015). As the majority acknowledges, this is wrong. The

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   elements cited by the plaintiffs distinguish legislative rules from policy
   statements, not interpretive rules, and ATF has not argued that its Rule is a
   policy statement. After attempting to apply these two inapposite criteria to
   ATF’s Final Rule, the plaintiffs conclude their discussion of the legislative-
   interpretive divide and move on.
           The majority forgives this misfire and attempts to fill the gap itself. I
   would not do so. While we might defensibly remedy a mistaken movant’s
   legal error if the error is small or readily correctable, that is not our situation.
   Discerning whether a rule is interpretive rather than legislative is difficult.
   Courts have described the distinction between interpretive and legislative
   rules as “‘fuzzy,’ ‘tenuous,’ ‘blurred,’ ‘baffling,’ and ‘enshrouded in
   considerable smog.’” Richard J. Pierce, Jr., Distinguishing Legislative Rules
   from Interpretative Rules, 52 Admin. L. Rev. 547, 547–48 (2000) (citing
   circuit-court cases). And the issue is not an obscure one. As one scholar
   recently observed, “the question of whether a supposedly informal
   pronouncement of an administrative agency is actually a rule that should have
   been adopted through notice-and-comment procedure may well be the single
   most frequently litigated and important issue of rulemaking procedure before
   the federal courts today.” Ronald M. Levin, Rulemaking and the Guidance
   Exemption, 70 Admin. L. Rev. 263, 265 (2018).                             The legislative-
   interpretive distinction is both complicated and significant.
           Indeed, as the majority observes, our court has not “laid out a clear
   test appropriate to resolve the question.” Ante, at 25. Nor would I use this
   case to establish such a test. Again, the plaintiffs’ briefing on the matter is a
   half-page discussion consisting entirely of legal error. 2 Predictably, at oral

           _____________________
           2
              ATF’s response brief is hardly better, reciting a generic definition of interpretive
   rules to assert that its Final Rule is interpretive.

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   argument there was little, if any, discussion of the “factors” the majority now
   adopts as the law of our circuit. Judicial restraint strongly counsels against
   the creation and application of a new test, in an infamously difficult area of
   administrative law, in an expedited matter, without the benefit of meaningful
   adversarial briefing.
          Reflective of these difficulties, the test crafted and applied by the
   majority creates more problems than solutions. Most significantly, the last
   of the majority’s five factors, which it describes as “primary,” ante, at 29, is
   misplaced. The majority writes that, “in the Fifth Circuit, courts scrutinize
   ‘whether the rule will produce significant effects on private interests.’”
   Ante, at 26 (cleaned up). This “substantial-impact test,” the majority says,
   is the “primary means” to “determine whether a rule is the type Congress
   thought appropriate for public participation.” Ante, at 28-29 (cleaned up)
   (quoting Texas v. United States, 787 F.3d 733, 765 (5th Cir. 2015)). The
   majority then concludes that this factor “strongly favors determining the
   Final Rule to be legislative, not interpretive” because ATF estimates that the
   annualized cost of the Rule will exceed $240 million. Ante, at 29.
          On its own terms, factually, that assessment is plausible—$240
   million is a lot. The problem is that the “substantial-impact test” is not
   instructive in the interpretive-legislative analysis. The majority borrows its
   five factors from a district court’s analysis in another case against ATF. That
   district court, and this majority, find support for this fifth factor in Gulf
   Restoration Network v. McCarthy, 783 F.3d 227 (5th Cir. 2015). But Gulf
   Restoration did not involve the distinction between interpretive and
   legislative rules. It instead asked, for the purpose of judicial reviewability,
   whether an agency’s action was best understood as a nonenforcement
   decision or a denial of a rulemaking petition. Id. at 235. Gulf Restoration does
   not support the majority’s assertion that courts in this circuit “scrutinize”

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   the “effects on private interests” to distinguish legislative from interpretive
   rules. 3
              The majority’s later citation to Texas v. United States for its
   “substantial-impact test” further reveals that this factor does not belong. See
   787 F.3d at 765. In Texas, we explained that we use the substantial-impact
   test to “look beyond the label ‘procedural’ to determine whether a rule is of
   the type Congress thought appropriate for public participation.”                           Id.
   (alteration in original) (quoting U.S. Dep’t of Lab. v. Kast Metals Corp., 744
   F.2d 1145, 1153 (5th Cir. 1984)). But there is the crux: the substantial-impact
   test is instructive in assessing purportedly procedural rules—not interpretive
   rules. Procedural rules are enumerated separately in the APA as a type of
   agency action not subject to notice and comment. See 5 U.S.C. § 553(b)(A)
   (exempting from notice and comment “interpretative rules, general
   statements of policy, or rules of agency organization, procedure, or practice”
   (emphasis added)). Here, ATF has not asserted that the Final Rule is

              _____________________
              3
               While the court in Gulf Restoration did note that it is an “essential feature[] of
   substantive rules” to “grant rights, impose obligations, or produce other significant effects
   on private interests,” 783 F.3d at 236, the court did not apply this rubric to determine
   whether a rule was interpretive. And a run-down of that language indicates that it has no
   relevance to interpretive rules. In observing that “significant effects on private interests”
   is a feature of substantive rules, the court in Gulf Restoration cited the D.C. Circuit’s
   decision in American Hospital Ass’n v. Bowen, 834 F.2d 1037, 1045 (D.C. Cir. 1987). Bowen
   in turn sources this language from Batterton v. Marshall, 648 F.2d 694, 702 (D.C. Cir. 1980).
   And in Batterton, the D.C. Circuit introduced the language in describing positive features
   of legislative rules without reference to those rules’ specific, and distinct, non-legislative
   counterparts: interpretive rules, policy statements, and procedural rules. See 5 U.S.C.
   § 553(b)(A). The remainder of its opinion makes clear that a rule’s substantial effect on
   private interests bears on the distinction between legislative and procedural rules. Tellingly,
   the court does not refer again to “private rights and interests” until it assesses whether the
   challenged action is a rule of “agency organization, procedure, or practice.” Batterton, 648
   F.2d at 707-08. The test features nowhere in the court’s separate analysis of whether the
   agency’s action is an interpretive rule. See id. at 705-06.

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   procedural. 4 The substantial-impact test, “primary” for the majority, is not
   germane.
           We have said as much before, including in Kast Metals, from which the
   court in Texas derived its rule. There, we agreeingly quoted the D.C. Circuit
   that “the substantial impact test has no utility in distinguishing between
   [interpretive and substantive rules].” Kast Metals, 744 F.2d at 1155 n.19 (5th
   Cir. 1984) (first emphasis added) (second alteration in original) (quoting
   Cabais v. Egger, 690 F.2d 234, 238 (D.C. Cir. 1982)). Six months later, we
   rejected a plaintiff’s APA argument that the challenged regulation’s
   “‘substantial impact’ on affected parties nonetheless required notice and
   comment rulemaking,” because the “substantial impact test is not a vehicle
   for imposing judicial notions of procedural propriety over and above what the
   APA mandates.” Baylor Univ. Med. Ctr. v. Heckler, 758 F.2d 1052, 1061 (5th
   Cir. 1985).
           Other courts similarly confirm that a rule’s “substantial impact” tells
   us little about whether it is legislative rather than interpretive. E.g., Energy
   Rsrvs. Grp., Inc. v. Dep’t of Energy, 589 F.2d 1082, 1094–95 (Temp. Emer. Ct.
   App. 1978) (explaining that “under the ‘substantial impact’ test every

           _____________________
           4
              Instead, ATF has consistently argued—and the district court agreed—that the
   Final Rule is an interpretive rule, which “clarifies, rather than creates, law.” Flight
   Training Int’l, Inc. v. FAA, 58 F.4th 234, 240 (5th Cir. 2023) (citation omitted).
   Interpretive rules “advise the public of the agency’s construction of the statutes and rules
   which it administers.” Perez v. Mortgage Bankers Ass’n, 575 U.S. 92, 97 (2015) (citation
   omitted). That is what ATF has repeatedly explained that it is doing, both in the Final Rule
   and in its briefing to us. E.g., Final Rule at 6,478. Accordingly, as ATF further asserts, in
   any enforcement proceeding involving a firearm whose regulatory status is contested,
   courts would apply the statutory language, not the interpretative criteria embodied in
   ATF’s Final Rule. The loophole confounding citizens and ATF alike therefore should be
   ours to sort out, affording no Chevron deference to ATF’s interpretive input as laid out in
   the Rule. See United States v. Mead Corp., 533 U.S. 218, 232 (2001). Vitally, in such an
   enforcement proceeding, the court would have the benefit of assessing a particular firearm.

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   significant interpretative rule automatically becomes a legislative rule by
   virtue of its effect,” and that “[t]here is nothing in the APA to warrant
   employment of the ‘substantial impact’ test to classify interpretative and
   legislative rules”); Brit. Caledonian Airways, Ltd. v. C.A.B., 584 F.2d 982,
   989 (D.C. Cir. 1978) (“Merely because a Rule has a wide-ranging effect does
   not mean that it is ‘legislative’ rather than ‘interpretative.’” (citation
   omitted)).
           To summarize, the substantial-impact test, utilized by the majority, ill
   fits—indeed, inexorably answers 5—the question this case presents. That
   leaves the majority’s other four factors, which may or may not prove a
   workable means of distinguishing between legislative and interpretive rules.
   We cannot know. No party in the case has briefed the factors—their wisdom
   in general or their specific application to this Rule. The district court had no
   such opportunity either.
          In any event, these plaintiffs have rested a critical component of their
   APA claim on an analysis that is both cursory and incorrect. I would
   accordingly hold that, in this preliminary-injunction posture, they have failed
   to demonstrate that they are substantially likely to succeed on the merits of
   that claim, 6 as they have not shown that ATF’s Final Rule is legislative rather
   than interpretive and therefore subject to the APA’s notice-and-comment
   requirements.

           _____________________
          5
              See Energy Rsrvs. Grp., 589 F.2d at 1094–95.
          6
                Future Proof Brands, 982 F.3d at 288 (“A preliminary injunction is ‘an
   extraordinary remedy which should not be granted unless the party seeking it has clearly
   carried its burden of persuasion.’” (cleaned up) (emphasis added) (citation omitted)).

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                                          B.
          But even if they had, their APA claim would still fail. That’s because,
   even assuming that ATF’s Final Rule is legislative in nature, the plaintiffs
   have not shown that the APA’s procedural requirements were not met.
          Plaintiffs contend that ATF’s Final Rule does not sufficiently
   resemble the proposed rule, thereby depriving them of notice and an
   opportunity to comment. In a recent opinion, our court reiterated what the
   APA requires in this respect. See Huawei Techs. USA, Inc. v. Fed. Commc’ns
   Comm’n, 2 F.4th 421, 447-49 (5th Cir. 2021). We explained that an agency’s
   notice suffices if the final rule “is a ‘logical outgrowth’ of the proposed rule,
   meaning the notice must ‘adequately frame the subjects for discussion’ such
   that ‘the affected party “should have anticipated” the agency’s final course
   in light of the initial notice.’” Id. at 447 (quoting Nat’l Lifeline Ass’n v. FCC,
   921 F.3d 1102, 1115 (D.C. Cir. 2019)); see Long Island Care at Home, Ltd. v.
   Coke, 551 U.S. 158, 174 (2007). The notice need not “specifically identify
   every precise proposal which the agency might ultimately adopt.” Huawei,
   2 F.4th at 448 (cleaned up) (quoting Chem. Mfrs. Ass’n v. EPA, 870 F.2d 177,
   203 (5th Cir. 1989)). To the contrary, “[t]he APA notice requirement is
   satisfied if the notice fairly apprises interested persons of the subjects and
   issues the agency is considering.” Chem. Mfrs. Ass’n, 870 F.2d at 203.
          We are bound by our court’s Huawei standard, and ATF’s notice of
   the proposed rule easily meets it.
          While the plaintiffs complain that the Final Rule “scrap[ped]” the
   proposed Worksheet and its point system, this objection rings hollow in light
   of the overwhelmingly negative response to the Worksheet. ATF explained
   in its publication of the Final Rule that, “[a]fter careful consideration of the
   comments received regarding the complexity in understanding the proposed
   Worksheet,” as well as the “methodology used in the Worksheet,” the Final

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   Rule would not use the Worksheet and its point system. Final Rule at 6,480.
   This is a straightforward case, then, where “the changes reflected in the final
   rule were instigated by industry comments,” indicating that “the final rule
   was a logical outgrowth of the comments received.” Chem. Mfrs. Ass’n, 870
   F.2d at 203.
           Indeed, to find an example of the severe criticisms ATF received from
   persons fully “apprise[d] of the issues at stake,” id. at 217, we need look no
   further than a comment submitted by plaintiffs’ counsel on behalf of a gun-
   rights center.        The center protested that ATF’s Worksheet was
   “incomprehensible,” and “ill-defined,” and that, in practice, states will be
   “forc[ed] . . . to guess how the ATF may apply the Worksheet to a particular
   firearm.” Letter to Denise Brown from Cody J. Wisniewski, at 2, 15,
   Mountain States Legal Foundation, Center to Keep and Bear Arms (Sept. 8,
   2021). The center speculated that the classification process may be so
   “tedious and incomprehensible” that state agencies may “simply not
   cooperate with the ATF out of sheer inability.” Id. at 15. Far from an
   unanticipated change in course, the possible elimination of the Worksheet
   was the subject of extensive comment. 7               See Huawei, 2 F.4th at 448-49
   (explaining that an APA petitioner’s comments on the agency’s proposed

           _____________________
           7
             Other commenters criticized the point-based rigidity of the Worksheet system.
   E.g., Comment ID ATF-2021-0002-97129 (June 21, 2021) (criticizing ATF’s “hard-to-
   follow points system” under which, “if [a] gun scores four points or more in either of two
   separate sections, it would be automatically considered an SBR”); Comment ID ATF-
   2021-0002-133210 (Aug. 18, 2021) (criticizing “the use of . . . a rigid points system”
   because most “modern firearms” can “be easily modified in form and function”);
   Comment ID ATF-2021-0002-146180 (Aug. 30, 2021) (“disagree[ing] with the points
   scoring proposed” because, “[f]or example, the ability to use sights and stabilize a firearm
   off body should not automatically qualify the firearm as being designed for shoulder
   usage”).

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   rule undermined the petitioner’s assertion that it lacked fair notice of the
   final rule’s contents).
          The plaintiffs also broadly complain that the Final Rule replaced the
   proposed rule’s “objective” factors with “subjective” factors. They assert
   that the Worksheet used “objective measurement criteria,” while the Final
   Rule uses an “indeterminate multi-factor test” based on “subjective
   criteria,” with no explanation of “how these factors are to be weighed against
   each other.” But again, the plaintiffs’ own response to the proposed rule
   contradicts their argument. Most notably, the Firearms Policy Coalition—a
   plaintiff in this case—submitted a ten-page comment opposing the proposed
   rule. See Comment on Proposed Rule no. ATF 2021R-08, Firearms Policy
   Coalition (Sept. 8, 2021) [hereinafter, “Coalition Comment”].            In its
   comment, the Coalition complained that the proposed rule’s factors were
   “highly subjective,” “malleable,” and “indeterminate.” Id. at 3. It further
   protested that ATF proposed to “preserve ad hoc discretion” to classify a
   braced pistol as a short-barreled rifle irrespective of its Worksheet score, and
   that “such open-ended discretion renders the proposed criteria/factors
   meaningless.” Id. at 4. The Coalition characterized ATF’s discretion as
   “un-check-able,” “free-ranging,” and “unpredictable.” Id. It asserted that
   ATF’s discretion leaves “no meaningful objective criteria against which to
   measure its conduct.” Id. Again, then, plaintiffs’ own comments reveal that
   the proposed rule “should have enabled—and in fact, did enable—[them] to
   anticipate those aspects of the final rule [they] claim[] were not properly
   noticed.” Huawei, 2 F.4th at 448. And even if the Final Rule is, as the
   plaintiffs contend, “more subjective and . . . less consistent” than the
   Worksheet, that does not mean that the proposed rule did not provide
   adequate notice under the APA. It may be that ATF did not respond to the
   public’s comments as the plaintiffs would have liked, but the alleged “rug-
   pull” is difficult to square with the record.

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           Finally, plaintiffs protest that the Worksheet, unlike the Final Rule,
   had an “emphasis on the design of the firearm rather than possible uses.”
   But this line of argument is contradicted by the Final Rule itself, as well as—
   again—plaintiffs’ own comments. On the Rule itself, the design features of
   the firearm remain the overwhelming focus. ATF first asks whether the
   weapon is “equipped with an accessory, component, or other rearward
   attachment . . . that provides surface area that allows the weapon to be fired
   from the shoulder.” Final Rule at 6,480. Only if so, ATF proceeds to assess
   six factors, four of which pertain exclusively to the design of the firearm. Id.
   The other two factors—marketing materials and information about the
   device’s likely use—do, in a sense, look beyond the physical features of the
   device to perceive shoulder use, but the proposed rule provided notice of that
   pragmatic, objective likelihood as well. Tellingly, the Coalition complained
   about precisely this issue, writing that the proposed criteria “go beyond the
   design and manufacture of the weapon and seek to divine some heretofore
   unknowable intent.” 8 Coalition Comment at 3. Yet again, the complaints
   raised in this litigation were fully aired in comments to the agency. This is a
   meaningful indicator that the notice-and-comment requirement was
   satisfied. See Huawei, 2 F.4th at 448-49 (finding no notice-and-comment
           _____________________
           8
               Objections to ATF’s assessment of intent make little sense in light of the
   statute’s plain focus on “inten[t] to be fired from the shoulder.” 26 U.S.C. § 5845(c). As
   the First Circuit explained in upholding an ATF rule about silencers, “it is hard to believe
   that Congress intended to invite manufacturers to evade the NFA’s carefully constructed
   regulatory regime simply by asserting an intended use for a part that objective evidence in
   the record . . . indicates is not actually an intended one.” Sig Sauer, Inc. v. Brandon, 826
   F.3d 598, 602 (1st Cir. 2016). And while the court in Sig Sauer was focused on “objective
   evidence” in the form of physical design features, the same holds true for any and all
   objective evidence that is probative of intent—including, for example, how a device is
   actually used in the community. See Washington v. Davis, 426 U.S. 229, 253 (1976) (Stevens,
   J., concurring) (“Frequently the most probative evidence of intent will be objective
   evidence of what actually happened rather than evidence describing the subjective state of
   mind of the actor.”)

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   violation where the complaining litigant’s comments to the agency revealed
   that the agency’s “initial notice and subsequent comments alerted [the
   litigant] to the issues it flags” in court).
           ATF has candidly acknowledged the preexisting uncertainty as to its
   classification of braced pistols, above all because manufacturers have
   increasingly commercialized “braces” that appear indistinguishable from
   stocks. See supra note 1; Final Rule at 6,479. This is why ATF proposed its
   rule—to explain its approach to classification of these devices, a task
   necessary for its constitutionally mandated enforcement of Congress’s laws.
   See 86 Fed. Reg. at 30,826.              Hundreds of thousands of commenters
   responded, many critical of the point system embodied in the proposed
   Worksheet. Responsively, ATF revisited its proposed approach, eliminating
   the point system but retaining its best effort to identify design, manufacture,
   and usage criteria that give meaning to the congressional focus on whether a
   firearm is shoulder-fired.           Under our case law, I can find nothing
   objectionable in this process.
           For these reasons, I respectfully disagree with my colleagues that ATF
   violated the APA’s procedural requirements. 9 ATF’s proposed rule set out
   to “clarify when a rifle is ‘intended to be fired from the shoulder.’” 86 Fed.
   Reg. at 30,826. The proposal “fairly acquainted [the public] with the subject

           _____________________
           9
              My colleagues embrace the plaintiffs’ account of ATF’s supposed rug-pull, but
   in so doing—as with their interpretive-rule gloss—they perilously heighten the burden to
   a near-impossible one for executive enforcement of federal law. For example, the majority
   says that, to satisfy the logical-outgrowth standard, a proposed and final rule “must be alike
   in kind.” Ante, at 33. The majority cites no authority for this proposition. More
   importantly, an “alike in kind” requirement is at odds with our decades-old rule that the
   APA’s “notice requirement is satisfied if the notice fairly apprises interested persons of the
   subjects and issues the agency is considering.” Chem. Mfrs. Ass’n, 870 F.2d at 203
   (emphases added).

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   and issues” central to the Final Rule. Huawei, 2 F.4th at 449. That is “all
   § 553 demands.” Id. (citing Chem Mfrs. Ass’n, 870 F.2d at 203).
                                           C.
          Moreover, as the majority observes, APA deficiencies are subject to a
   harmless-error rule. United States v. Johnson, 632 F.3d 912, 930 (5th Cir.
   2011). The need to show prejudice is yet another obstacle to plaintiffs’ APA
   claim. Even if ATF’s Final Rule is legislative, and even if the Final Rule is not
   a logical outgrowth of the proposed rule, these plaintiffs were not prejudiced
   by any notice-and-comment deficiency. Plaintiffs fail to explain what it is
   they would have liked to say regarding the Final Rule that they were unable
   to say in response to the proposed rule. Because ATF’s “process addressed
   the same issues raised by [the plaintiffs] and because [they] ‘make[] no
   showing that the outcome of the process would have differed . . . had notice
   been at its meticulous best,’” id. at 933 (citation omitted), any APA
   deficiency on ATF’s part was harmless.
                                   *        *         *
          I would affirm Judge O’Connor’s conclusion that the plaintiffs have
   failed to demonstrate a likelihood of success on the merits of their APA claim.

                                           II.
          The majority’s finding on the APA claim has obviated any need to
   assess the plaintiffs’ Second Amendment challenge. But Judge Willett’s
   succinct concurring views may benefit from an equally succinct counterpoint.

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                                          A.
          Judge Willett says that braces on pistols improve accuracy, and that
   “[a]ccuracy, in turn, promotes safety.” Ante, at 41 (Willett, J.). In his view,
   “making common, safety-improving modifications” to guns is Second-
   Amendment-protected conduct. Id.
          I disagree that these braces are, in relevant regard, “safety-improving
   modifications.” After all, as a plurality of the Supreme Court has observed,
   it is “clear from the face of the [NFA] that [its] object was to regulate certain
   weapons likely to be used for criminal purposes,” and “the regulation of
   short-barreled rifles . . . addresses a concealable weapon likely to be so used.”
   United States v. Thompson/Ctr. Arms Co., 504 U.S. 505, 517 (1992) (plurality
   opinion) (emphasis added).       Indeed, as some commenters observed in
   response to ATF’s proposed rule, “short-barreled rifles are uniquely
   dangerous because they ‘combine the power of shoulder-mounted rifles with
   the concealability of handguns’ and . . . ‘stabilizing braces’ are functionally
   equivalent to shoulder stocks.” Final Rule at 6,498. Other commenters,
   “including former law enforcement officers,” favored the proposed rule
   because braced pistols, “as evidenced by their use in the Boulder[, Colorado]
   and Dayton[, Ohio] mass shootings, ‘are unusually dangerous because they
   can be easily concealed like a handgun but have the firepower and accuracy of a
   rifle.’” Id. (emphases added). Increased concealability and accuracy, at least
   in the hands of killers, is not “safe”—it is lethal.
                                          B.
          Relatedly, I agree with the district court that these plaintiffs are far
   from demonstrating a substantial likelihood of success on their challenge
   under New York State Rifle & Pistol Ass’n, Inc. v. Bruen, 142 S. Ct. 2111
   (2022).

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          First, until told otherwise by the Supreme Court, I am persuaded that
   uniquely dangerous weapons, including short-barreled rifles, are not covered
   by the Second Amendment. As the Supreme Court recognized in Heller,
   “the Second Amendment does not protect those weapons not typically
   possessed by law-abiding citizens for lawful purposes.” District of Columbia
   v. Heller, 554 U.S. 570, 625 (2008). That’s because there is a “historical
   tradition of prohibiting the carrying of ‘dangerous and unusual weapons.’”
   Id. at 627 (citing, inter alia, 4 Commentaries on the Laws of
   England 148-49 (1769)). And the Supreme Court’s more recent decision
   in Bruen left Heller’s dangerous-and-unusual carveout intact. See Bruen, 142
   S. Ct. at 2128, 2143. Accepting, as the plaintiffs do, 10 that “short-barred
   rifles” are constitutionally regulated under the NFA, I fail to see how ATF’s
   Final Rule, which merely identifies criteria for classifying materially
   indistinguishable devices alike—that is, as SBRs—implicates the text of the
   Second Amendment.
          Second, it bears emphasizing that ATF’s Final Rule, like the NFA
   itself, does not ban anything. The NFA is instead a registration law, akin to
   a licensing regime, which the plurality in Bruen was careful to point out as
   requiring fact-specific assessment. See id. at 2138 n.9. The plurality told us
   that some licensing regimes pose no constitutional problem because they do
   not necessarily burden the Second Amendment right. Id.; cf. United States v.
   McNulty, No. 22-10037, __ F. Supp. 3d __, 2023 WL 4826950, at *5
   (D. Mass. July 27, 2023) (“[I]t is incorrect to posit that Bruen has upended
   the presumptive constitutionality of measures seeking to regulate firearms
   commerce.”). In this case, these plaintiffs have failed to demonstrate that
   the NFA’s century-old registration scheme for uniquely dangerous

          _____________________
          10
               Plaintiffs do not lodge a constitutional attack against the NFA itself.

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   devices—upheld long ago by the Supreme Court in United States v. Miller,
   307 U.S. 174, 178 (1939)—is more like New York’s licensing system struck
   down in Bruen, rather than the permissible regimes accepted as constitutional
   in the plurality’s footnote 9.

                                        III.
          While I dissent from the reversal of Judge O’Connor’s denial of a
   preliminary injunction, I note that the majority has remanded to the district
   court with no restrictions. I join the majority to emphasize that Judge
   O’Connor is free to go in any direction, including limiting any injunctive
   relief to an appropriately narrow scope, or finding that the balance of equities
   favors issuing no injunction at all. As the majority acknowledges, a district
   court is best positioned to make these determinations in the first instance.

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