United States Court of Appeals 

for the Federal Circuit ______________________ 

NATIONAL ORGANIZATION OF VETERANS’ 

ADVOCATES, INC., PETER CIANCHETTA, 

MICHAEL REGIS, ANDREW TANGEN,

Petitioners

v.

SECRETARY OF VETERANS AFFAIRS,

Respondent

______________________ 

2020-1321

______________________ 

Petition for review pursuant to 38 U.S.C. Section 502.

______________________ 

Decided: September 20, 2022

______________________ 

BLAKE E. STAFFORD, Latham & Watkins LLP, Washington, DC, argued for petitioners. Also represented by 

SHANNON MARIE GRAMMEL, ROMAN MARTINEZ. 

 MOLLIE LENORE FINNAN, Commercial Litigation 

Branch, Civil Division, United States Department of Justice, Washington, DC, argued for respondent. Also represented by BRIAN M. BOYNTON, ERIC P. BRUSKIN, MARTIN F.

HOCKEY, JR.; JULIE HONAN, Y. KEN LEE, Office of General 

Counsel, United States Department of Veterans Affairs, 

Washington, DC. 

 ______________________ 

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2 NOVA v. SECRETARY OF VETERANS AFFAIRS

Before NEWMAN, PROST, and CUNNINGHAM, Circuit 

Judges.

Opinion for the court filed by Circuit Judge CUNNINGHAM. 

Dissenting opinion filed by Circuit Judge PROST.

CUNNINGHAM, Circuit Judge.

At the heart of the government’s scheme for awarding 

disability benefits to veterans is a rating schedule. The Department of Veterans Affairs adopted this rating schedule 

to standardize the evaluation of how severely diseases and 

injuries resulting from military service impair veterans’ 

earning capacity. 38 C.F.R. § 4.1. The rating schedule is, 

in turn, divided into diagnostic codes that provide disability ratings for various symptoms or conditions.

National Organization of Veterans’ Advocates, Inc., Peter Cianchetta, Michael Regis, and Andrew Tangen petition this court under 38 U.S.C. § 502 to review the VA’s

interpretation of two of these diagnostic codes: DCs 5055 

and 5257, both found at 38 C.F.R. § 4.71a. The VA set out 

its interpretation of DC 5055 in Agency Interpretation of 

Prosthetic Replacement of a Joint, 80 Fed. Reg. 42,040 

(July 16, 2015) (the “Knee Replacement Guidance” or 

“Guidance”), and VA Adjudication Procedures Manual 

M21-1 Section III.iv.4.A.6.a (the “Knee Replacement Manual Provision”). The VA set out its interpretation of 

DC 5257 in Manual Section III.iv.4.A.6.d (the “Knee Joint 

Stability Manual Provision”). 

For the reasons provided below, we conclude that the 

Knee Replacement Manual Provision is not a reviewable 

agency action. We also hold that the Knee Replacement 

Guidance is arbitrary and capricious under the controlling 

precedent of Hudgens v. McDonald, 823 F.3d 630 (Fed. Cir. 

2016). Finally, we dismiss the challenge to the Knee Joint 

Stability Manual Provision as moot. Accordingly, we 

grant-in-part and dismiss-in-part the petition.

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NOVA v. SECRETARY OF VETERANS AFFAIRS 3

BACKGROUND

I. The VA’s Interpretation of DC 5055

Petitioners seek review of two interpretive rules. To 

introduce the VA’s interpretation of DC 5055, we must 

turn back to the claim at issue in Hudgens. In that case, 

the VA regional office (“RO”) denied Michael A. Hudgens, 

a U.S. Army veteran, a 100-percent disability evaluation 

for his partial prosthetic knee replacement under DC 5055 

because the RO found that DC 5055 applied only to total 

knee replacements. Hudgens, 823 F.3d at 632–33. The 

Board of Veterans’ Appeals and the United States Court of 

Appeals for Veterans Claims both affirmed the RO’s conclusion that DC 5055 did not apply to Mr. Hudgens’s partial knee replacement claim. Id. at 633–34. Mr. Hudgens 

then appealed to this court. Id. at 634.

On July 16, 2015, twelve days before the Secretary’s final brief in Hudgens was due with this court, the VA published the Knee Replacement Guidance. Id. The Guidance 

stated that the VA was providing notice of the agency’s 

“longstanding interpretation of DCs 5051 to 5056” as 

providing for a 100-percent evaluation “when the total 

joint, rather than the partial joint, has been replaced by a 

prosthetic implant.” 80 Fed. Reg. at 42,040. The VA also 

announced in the Guidance that an “explanatory note” 

would be added to 38 C.F.R. § 4.71a stating that the “term 

‘prosthetic replacement’ in diagnostic codes 5051 through 

5056 means a total replacement of the named joint.”1 Id.

at 42,041.

In Hudgens, we nevertheless reversed the judgment of 

the Veterans Court and remanded for further proceedings. 

1 The VA also included an exception to this interpretation for DC 5054, which relates to hip replacements. 

Knee Replacement Guidance, 80 Fed. Reg. at 42,041–42. 

That exception is not relevant here. 

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4 NOVA v. SECRETARY OF VETERANS AFFAIRS

823 F.3d at 640. We held that DC 5055 “does not unambiguously exclude [partial knee] replacements.” Id. at 637 

(emphasis omitted). We further concluded that the Secretary’s interpretation of DC 5055 could not be afforded Auer

deference for two reasons. First, the Secretary’s interpretation “conflict[ed]” with “numerous inconsistent rulings by 

the Board” holding that partial knee replacements could be 

evaluated under DC 5055. Id. at 638–39. Second, the Knee 

Replacement Guidance was a “post hoc rationalization” 

“conveniently adopted to support the Veterans Court’s interpretation in this case.” Id. at 639. Finally, we held that 

Mr. Hudgens’s “interpretation of DC 5055 is permitted by 

the text of the regulation,” meaning that we had to apply 

the pro-veteran canon, see id.; see also Brown v. Gardner, 

513 U.S. 115, 117–18 (1994), and “resolve any doubt in the 

interpretation of DC 5055 in his favor,” Hudgens, 823 F.3d 

at 639. His claim, therefore, could be evaluated under 

DC 5055. Id.

On November 21, 2016, six months after our decision 

in Hudgens, the VA informed RO adjudicators of how the 

agency intended to reconcile our decision in that case with 

the Knee Replacement Guidance. J.A. 4, 28. In the Knee 

Replacement Manual Provision, the VA directed RO adjudicators to not evaluate under DC 5055 any claims for partial knee replacements “filed and decided on or after July 

16, 2015.” J.A. 28. Claims filed before July 16, 2015, and

pending as of that date were to be evaluated under 

DC 5055 if doing so would be more favorable than evaluating the same claims under another applicable diagnostic 

code. Id. Finally, claims filed before July 16, 2015, and 

adjudicated before that date were not to be revised. Id.

Four years later, the VA amended DC 5055 following 

notice-and-comment to “clarify VA’s intent to provide a 

minimum evaluation following only total joint replacement.” Schedule for Rating Disabilities: Musculoskeletal 

System and Muscle Injuries, 85 Fed. Reg. 76,453, 76,454, 

76,456 (Nov. 30, 2020). The change was effective February 

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NOVA v. SECRETARY OF VETERANS AFFAIRS 5

7, 2021. Id. at 76,453. On February 8, the VA rescinded 

the Knee Replacement Manual Provision. J.A. 246–47. 

But “the new Manual provisions still reference the historical Knee Replacement Manual Provision because adjudicators use the historical guidance to rate claims that were 

pending as of February 7, 2021[,] and that include rating 

periods prior to that date.” Resp’t’s Br. 12; see J.A. 318. 

II. The VA’s Interpretation of DC 5257

The second rule was stated in the Knee Joint Stability 

Manual Provision. When this Manual provision was promulgated in 2018, J.A. 111, 113, DC 5257 assigned a 10-percent rating for “Slight” knee instability, a 20-percent rating 

for “Moderate” instability, and a 30-percent rating for “Severe” instability. 38 C.F.R. § 4.71a (2018). The Knee Joint 

Stability Manual Provision directed RO adjudicators to determine whether a claimant had slight, moderate, or severe 

instability by measuring the amount of movement in the 

joint. J.A. 113. The Manual provision associated slight instability with 0–5 millimeters of joint translation, moderate instability with 5–10 millimeters of joint translation, 

and severe instability with 10–15 millimeters of joint 

translation. Id. On January 21, 2021, following our decision in National Organization of Veterans’ Advocates, Inc. 

v. Secretary of Veterans Affairs, 981 F.3d 1360 (Fed. Cir. 

2020) (en banc) (“NOVA 2020”), the VA rescinded the Knee

Joint Stability Manual Provision. J.A. 183, 228.

III. The Instant Appeal

On January 3, 2020, NOVA filed a petition for review 

of the Knee Replacement Manual Provision and the Knee 

Joint Stability Manual Provision. NOVA 2020, 981 F.3d at 

1365–66. NOVA later amended the petition to add Messrs. 

Cianchetta, Regis, and Tangen—three members of 

NOVA—as petitioners and to challenge the Knee Replacement Guidance. Id. at 1368. In NOVA 2020, we held that 

NOVA has associational standing to challenge the Guidance and both Manual provisions. Id. at 1371. We further 

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6 NOVA v. SECRETARY OF VETERANS AFFAIRS

held that we have jurisdiction under 38 U.S.C. § 502 to review the VA’s interpretation of DCs 5055 and 5257.2 Id. at 

1378, 1382. It was left for a merits panel to determine 

whether the Knee Replacement Guidance or the Knee Replacement Manual Provision constitutes an independently

reviewable interpretive rule and to render a decision on the 

merits of the petition. Id. at 1383, 1386. 

DISCUSSION

I. The Knee Replacement Manual Provision

We begin by resolving the jurisdictional question left 

open by NOVA 2020. We hold that the Knee Replacement 

Guidance—not the Knee Replacement Manual Provision—

constitutes the final agency action subject to review under 

§ 502. As we explained in NOVA 2020: “Manual provisions 

that merely republish prior agency interpretations or restate existing law . . . are not reviewable under section 

502.” Id. at 1382.

The Knee Replacement Guidance predates the Knee 

Replacement Manual Provision, and the Manual provision 

makes no “substantive change” to the Guidance. Id.; see 

J.A. 1, 25, 28–29. The Manual provision takes as its key 

date July 16, 2015, the day the VA promulgated the Guidance. J.A. 1, 28. For partial knee replacement claims filed 

on or after that date, the Manual provision directs RO adjudicators not to award evaluations under DC 5055, 

thereby implementing the rule put forward in the Guidance. J.A. 1, 28. The Manual provision even explains that 

its rule stems from the explanatory note added by the Guidance. J.A. 28. Under the Manual provision, partial knee 

2 Specifically, we have jurisdiction over the amended 

petition because either the Knee Replacement Guidance or 

the Knee Replacement Manual Provision is reviewable under § 502, regardless of which is the reviewable interpretive rule under § 552(a)(1). NOVA 2020, 981 F.3d at 1382.

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NOVA v. SECRETARY OF VETERANS AFFAIRS 7

replacement claims filed before July 16, 2015, may still be 

evaluated under DC 5055, such that the Knee Replacement 

Guidance has no effect on their adjudication. J.A. 28–29. 

Petitioners contend that this “temporal limitation is 

not contained in the Knee Replacement Guidance,” so the 

Manual provision is substantively different from the Guidance. Pet’rs’ Br. 50. But there is no suggestion in the Guidance that it is to have retroactive effect; indeed, the 

Guidance states that it has an effective date of July 16, 

2015. J.A. 1. Thus, the Manual provision does not provide 

instructions to RO adjudicators that are substantively inconsistent with the Knee Replacement Guidance. Because 

it “merely republish[es]” the Guidance, the Knee Replacement Manual Provision is not a final agency action subject 

to review under § 502. NOVA 2020, 981 F.3d at 1382–83. 

II. The Knee Replacement Guidance

Having concluded that the Knee Replacement Guidance is the reviewable agency action, we now consider 

whether the Guidance is arbitrary and capricious. We conclude that it is.

A. Standard of Review

“We review petitions under 38 U.S.C. § 502 in accordance with the standard set forth in the Administrative Procedure Act (‘APA’), 5 U.S.C. §§ 701–706.” Paralyzed 

Veterans of Am. v. Sec’y of Veterans Affs., 345 F.3d 1334, 

1339 (Fed. Cir. 2003) (citing Nyeholt v. Sec’y of Veterans 

Affs., 298 F.3d 1350, 1355 (Fed. Cir. 2002)). Under the 

APA, we “hold unlawful and set aside agency action” that 

is “arbitrary [and] capricious,” is “not in accordance with 

law,” or is promulgated “without observance of procedure 

required by law.” 5 U.S.C. §§ 706(2)(A), (D).

B. The Text of DC 5055

We are asked to determine whether the VA’s interpretation of DC 5055 is arbitrary and capricious or contrary to 

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8 NOVA v. SECRETARY OF VETERANS AFFAIRS

law. As always, we begin our analysis by looking to the 

regulatory text. See Chase Bank USA, N.A. v. McCoy, 562 

U.S. 195, 204 (2011). “[I]f there is only one reasonable construction of a regulation,” then a court should not defer to 

any conflicting agency interpretation. Kisor v. Wilkie, 139 

S. Ct. 2400, 2415 (2019). 

We look to the text of DC 5055 on the date that the VA 

promulgated the Knee Replacement Guidance. See Chase 

Bank, 562 U.S. at 204. On July 16, 2015, DC 5055 stated:

5055 Knee replacement (prosthesis).

Prosthetic replacement of knee joint:

For 1 year following implantation of prosthesis 

..................... 100

With chronic residuals consisting of severe 

painful motion or weakness in the affected extremity ..................... 60

With intermediate degrees of residual 

weakness, pain or limitation of motion rate 

by analogy to diagnostic codes 5256, 5261, 

or 5262.

Minimum rating ..................... 30

38 C.F.R. § 4.71a (2015).

In Hudgens, we held that DC 5055 does not unambiguously exclude partial knee replacements. 823 F.3d at 637. 

Accordingly, the text of DC 5055 does not resolve whether 

the Knee Replacement Guidance is arbitrary and capricious. Id. at 637–38. The Secretary argues that we are not 

bound by this holding in Hudgens because DC 5055 has 

subsequently been “clarified” by the addition of the explanatory note. Resp’t’s Br. 31. The Secretary asserts that the 

explanatory note is “plain and unambiguous” in stating 

that “the term ‘prosthetic replacement’ in diagnostic 

codes 5051 through 5056 means a total replacement of the 

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NOVA v. SECRETARY OF VETERANS AFFAIRS 9

named joint.” Id. at 30 (quoting 38 C.F.R. § 4.71a, 

DCs 5051–56, Note (2020)).

We reject this circular argument. We are evaluating 

whether the Guidance constitutes a valid interpretation of 

DC 5055. The Guidance itself inserted the explanatory 

note into DC 5055. J.A. 1–3. The Secretary would have us 

hold that the Guidance articulates the only reasonable 

reading of DC 5055 because the Guidance itself says so. 

See generally Resp’t’s Br. 29–31. That cannot be correct. 

Indeed, the Secretary’s argument contravenes a basic tenet 

of administrative law. Agencies must “use the same procedures when they amend or repeal a rule as they used to 

issue the rule in the first instance.” Perez v. Mortg. Bankers Ass’n, 575 U.S. 92, 101 (2015); see 5 U.S.C. § 551(5). 

The VA promulgated DC 5055 following notice-and-comment rulemaking procedures in 1978. Updating the Schedule for Rating Disabilities, 43 Fed. Reg. 45,348, 45,348–50 

(Oct. 2, 1978). Therefore, the Secretary cannot have 

amended DC 5055 without going through notice-and-comment.

In Hudgens, we considered the same version of 

DC 5055 that existed when the VA promulgated the Knee 

Replacement Guidance. Compare 38 C.F.R. § 4.71a (2015), 

with Hudgens, 823 F.3d at 632 (quoting 38 C.F.R. § 4.71a). 

We thus follow Hudgens and conclude that DC 5055 is ambiguous as to whether it includes partial knee replacements.

C. Deference 

We next consider, as we did in Hudgens, whether we 

must defer to the Secretary’s interpretation under Auer v. 

Robbins, 519 U.S. 452 (1997). We conclude that Hudgens

is still controlling precedent and so we cannot afford the 

Secretary’s interpretation Auer deference. 

In Hudgens, we gave two reasons for why the Secretary’s interpretation of DC 5055—excluding partial knee 

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10 NOVA v. SECRETARY OF VETERANS AFFAIRS

replacements—was not entitled to Auer deference. 823 

F.3d at 638–39. First, “the agency’s interpretation conflict[ed] with a prior [agency] interpretation”—namely, 

“numerous inconsistent rulings by the Board.” Id. at 638

(second brackets in original) (quoting Christopher v. 

SmithKline Beecham Corp., 567 U.S. 142, 155 (2012)). Second, the Secretary’s interpretation was a “post hoc rationalization” “adopted to support the Veterans Court’s 

interpretation.” Id. at 639. The second reason regarding 

post hoc rationalization is not relevant here as we are addressing only the interpretation put forward in the Knee 

Replacement Guidance, not a previous agency interpretation that the Secretary is justifying with the Knee Replacement Guidance. See Oral Arg. at 01:47–02:07, available at

https://oralarguments.cafc.uscourts.gov/default.aspx?fl=20

-1321_12092021.mp3 (“Q: [G]oing forward, if [the Guidance] therefore is not to advance a defense of past agency 

action, we are now talking about using it to defend subsequent agency action. To me, that’s a real distinction that 

has heft, right? A [from petitioners]: I agree it’s a distinction, your honor.”). Therefore, this leaves our first reason

in Hudgens that “numerous inconsistent rulings by the 

Board” foreclose the VA’s interpretation. 823 F.3d at 638. 

The Secretary contends that we should not characterize Board interpretations “as representing the agency’s official position.” Resp’t’s Br. 33–35. The Secretary notes 

that “to receive Auer deference, ‘the interpretation must at 

least emanate from those actors, using those vehicles, understood to make authoritative policy in the relevant context.’” Id. at 34 (internal brackets omitted) (quoting Kisor, 

139 S. Ct. at 2416). The Board is not such an authoritative 

actor, the Secretary asserts, because it issues more than 

100,000 non-precedential decisions a year where the judges 

act individually rather than in panels. Id. at 35 (citing 

Board of Veterans’ Appeals Annual Report to Congress 

(FY 2020), https://www.bva.va.gov/docs/Chairmans_Annual_Rpts/BVA2020AR.pdf). In the Secretary’s view, these 

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NOVA v. SECRETARY OF VETERANS AFFAIRS 11

facts, together with our statement in NOVA 2020 that 

Board decisions “appear not to be entitled to Auer deference,” 981 F.3d at 1382 n.14, “erodes the foundation” of our 

holding in Hudgens, Oral Arg. at 29:50–52.

The Secretary’s argument is beside the point. Neither 

in Hudgens nor in this case is the issue whether Board decisions are entitled to Auer deference. See id. at 17:28–

18:00 (petitioners emphasizing that they are not arguing 

that Board decisions should be entitled to Auer deference). 

Rather, the issue is whether the existence of conflicting 

prior Board decisions can preclude the application of Auer

deference to the subsequent VA interpretation in the Knee 

Replacement Guidance. As we explain below, no relevant 

law or facts have changed since our decision in Hudgens, 

and so we continue to be bound by our conclusion that prior 

conflicting Board decisions interpreting DC 5055 preclude 

application of Auer deference to the Knee Replacement 

Guidance.

Since our decision in Hudgens, the Supreme Court has

addressed Auer deference in Kisor. In Kisor, the Court 

found “it worth reinforcing some of the limits inherent in 

the Auer doctrine.” 139 S. Ct. at 2415. First, the Supreme 

Court held that before applying Auer deference, courts 

must “carefully consider the text, structure, history, and 

purpose of a regulation” and conclude that “the regulation 

is genuinely ambiguous.” Id. Second, the agency’s interpretation must also be “reasonable” and “come within the 

zone of ambiguity the court has identified after employing 

all its interpretive tools.” Id. at 2415–16. Third, “a court 

must make an independent inquiry into whether the character and context of the agency interpretation entitles it to 

controlling weight.” Id. at 2416. This third part of the Auer

inquiry is relevant here. The Supreme Court gave a list of

several “especially important markers for identifying when 

Auer deference is and is not appropriate” given the character and context of the interpretation. Id.

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12 NOVA v. SECRETARY OF VETERANS AFFAIRS

The first of these markers, the Court explained, is that 

only “authoritative” agency interpretations should be afforded Auer deference. Id. “That constraint follows from 

the logic of Auer deference—because Congress has delegated rulemaking power, and all that typically goes with it, 

to the agency alone.” Id. In other words, Auer deference is 

available only when agencies exercise their “delegated 

rulemaking power.” 

But not all agency actions exercising such power can 

receive Auer deference. See Kristin E. Hickman & Richard 

J. Pierce, Jr., Administrative Law § 3.8.3 (6th ed. 2022) 

(summarizing that under Kisor an agency interpretation 

being “authoritative” is one of five conditions that must be 

met before that interpretation can receive Auer deference). 

The Supreme Court proceeded to separately summarize 

case law holding that an agency interpretation should not 

receive Auer deference when it conflicts with a prior interpretation and “creates ‘unfair surprise’ to regulated parties.” Kisor, 139 S. Ct. at 2417–18 (quoting Long Island 

Care at Home, Ltd. v. Coke, 551 U.S. 158, 170 (2007)). Such 

agency actions do not reflect the “fair and considered judgment” of the agency. Id. at 2417 (quoting Christopher, 567 

U.S. at 155). Where there is such an “upending of reliance,” 

the lack of “‘fair warning’ outweigh[s] the reasons to apply 

Auer.” Id. at 2418 (quoting Christopher, 567 U.S. at 156). 

Accordingly, the primary concern of this constraint on Auer

deference is the expectations that the agency has previously engendered. 

Indeed, an agency can create such expectations even if 

it has not previously put forward an “authoritative” agency 

interpretation. Id. at 2418 (“[T]he upending of reliance 

may happen without such an explicit interpretive 

change.”); see also Romero v. Barr, 937 F.3d 282, 291 (4th 

Cir. 2019) (“[T]he upending of reliance may happen without such an explicit interpretive change. Rather, an agency 

may—instead of issuing a new interpretation that conflicts 

with an older one—set forth an interpretation for the first 

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NOVA v. SECRETARY OF VETERANS AFFAIRS 13

time that is contrary to an established practice to which the 

agency has never objected.” (internal citation omitted)). As 

Kisor explains, in Christopher, the Supreme Court “refused 

to defer to an interpretation that would have imposed retroactive liability on parties for longstanding conduct that 

the agency had never before addressed.” Kisor, 139 S. Ct. 

at 2418 (citing Christopher, 567 U.S. at 155–56). In other 

words, even the absence of prior agency action can cause a 

new interpretation to be an “upending of reliance,” preventing that interpretation from receiving Auer deference. 

Christopher, 567 U.S. at 155–58. Kisor merely reiterated 

that conflicting agency interpretations cannot receive Auer

deference because they cause “unfair surprise” or an “upending of reliance.” 139 S. Ct. at 2417–18 (quoting Long 

Island, 551 U.S. at 170); accord Charles H. Koch, Jr. & 

Richard Murphy, 3 Administrative Law & Practice § 10:26

(3d ed. 2022) (“In Christopher . . . the circumstance that 

mattered most to the Court was the element of unfair surprise.”). Kisor did not change the exception to Auer deference applied in Hudgens. See Hudgens, 823 F.3d at 638–39 

(citing Christopher, 567 U.S. at 155).

The fact that the Board, as it did before Hudgens, issues numerous non-precedential decisions by single judges

each year does not alter our decision. Of the relevant Board 

decisions issued before the VA promulgated the Guidance, 

the vast majority applied DC 5055 to partial knee replacements. Id. at 637–38 & n.3 (noting Mr. Hudgens’s argument that 17 out of 21 Board decisions issued prior to 

Hudgens interpreted DC 5055 to cover partial knee replacements); Hudgens v. Gibson, 26 Vet. App. 558, 566 

(2014) (“Gibson”) (Kasold, C.J., dissenting) (noting that 

there were “at least 11 Board decisions that have interpreted DC 5055 to cover partial knee replacements and 

only 3 that have interpreted it as limited solely to total 

knee replacements”), rev’d sub nom. Hudgens v. McDonald, 

823 F.3d 630 (Fed. Cir. 2016). And although Board decisions are non-precedential and issued by single judges, 

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14 NOVA v. SECRETARY OF VETERANS AFFAIRS

they are—as we held in Hudgens—“the final decision[s] for 

the Secretary on all questions in matters affecting the provision of benefits” and provide persuasive authority to the 

Veterans Court on the interpretation of regulations. Hudgens, 823 F.3d at 638 (quoting Gibson, 26 Vet. App. at 566 

(Kasold, C.J., dissenting) (citing 38 U.S.C. § 7104(c))). As 

such, there is “weight accorded to Board interpretations of 

VA regulations” that can engender reliance interests and 

foreclose application of Auer deference to the later conflicting Knee Replacement Guidance.3 Id. 

3 The dissent concludes that the Guidance does not 

upend reliance because it applies prospectively and not retrospectively. Diss. at 3. But the dissent does not identify 

cases where courts have relied on a distinction between 

prospective and retrospective conflicting agency interpretations. Instead, the Supreme Court has held that the “disruption of expectations may occur when an agency 

substitutes one view of a rule for another.” Kisor, 139 S Ct. 

at 2418. An agency interpretation is not entitled to Auer 

deference when the interpretation “does not reflect the 

agency’s fair and considered judgment,” which may occur 

“when the agency’s interpretation conflicts with a prior interpretation” or is a “post hoc rationalization.” Christopher, 567 U.S. at 155. Thus, courts have not given Auer

deference to conflicting agency interpretations that are applied in subsequent proceedings. See, e.g., Romero, 937 

F.3d at 296–97 (declining to give Auer deference to precedential decision of Attorney General that Board of Immigration Appeals applied to end administrative closure of 

case); Rafferty v. Denny’s, Inc., 13 F.4th 1166, 1187 (11th 

Cir. 2021) (declining to give Auer deference to agency Opinion Letter issued prior to filing of complaint at issue). The 

Guidance, like the Board decision in Hudgens, conflicts 

with prior interpretations, which forecloses Auer deference. See Hudgens, 823 F.3d at 637–38 & n.3.

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NOVA v. SECRETARY OF VETERANS AFFAIRS 15

We are thus still bound by the conclusion in Hudgens

that the interpretive rule embodied in the Knee Replacement Guidance cannot qualify for Auer deference because

it conflicts with most prior Board decisions interpreting

DC 5055. See id. at 638–39.

D. Pro-Veteran Canon of Construction

We also must follow Hudgens, apply the pro-veteran 

canon, and defer to Petitioners’ interpretation of DC 5055.4 

We held in Hudgens that “[e]ven if the government’s asserted interpretation of DC 5055 is plausible, it would be 

appropriate under [the pro-veteran canon] only if the [regulatory] language unambiguously supported the government’s interpretation.” Id. at 639 (cleaned up) (quoting 

Sursely v. Peake, 551 F.3d 1351, 1357 (Fed. Cir. 2009)). Petitioners’ interpretation of DC 5055, which is the same as 

that of Mr. Hudgens, “is permitted by the text of the regulation.” Id. “DC 5055 is under the heading ‘Prosthetic Implants’ and merely lists a schedule of ratings for the 

condition ‘Knee replacement (prosthesis),’ without elaboration or limitation of the condition.” Id. (citing 38 C.F.R. 

§ 4.71a (2015)). The Secretary argues that we are not 

bound by the analysis of the pro-veteran canon in Hudgens 

only because the VA has subsequently added the explanatory note. Resp’t’s Br. 36–37. But we have already concluded that the explanatory note cannot influence our 

interpretation of DC 5055. So, we follow Hudgens, apply 

4 “This court has not definitively resolved at what 

stage the pro-veteran canon applies and whether it precedes any claims of deference to an agency interpretation.” 

Roby v. McDonough, 2021 WL 3378834, at *8 (Fed. Cir. 

Aug. 4, 2021). Because we conclude that the Secretary’s 

interpretation is not entitled to Auer deference, we decline 

to opine on whether the pro-veteran canon precedes or follows Auer deference.

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16 NOVA v. SECRETARY OF VETERANS AFFAIRS

the pro-veteran canon, and resolve any doubt in Petitioners’ favor.

* * *

For these reasons, we conclude that the Secretary’s interpretation of DC 5055 is arbitrary and capricious and vacate the Knee Replacement Guidance.

III. The Knee Joint Stability Manual Provision

Finally, we turn to the Knee Joint Stability Manual 

Provision. The parties agree that this issue is moot because the Secretary rescinded the Manual provision. 

Pet’rs’ Br. 54–55; Resp’t’s Br. 55–56. We concur. Although 

Petitioners ask us to declare that the Manual provision is 

invalid ab initio, see Pet’rs’ Br. 55, we do not have the authority to make such a ruling on the merits when the issue 

is moot, see Powell v. McCormack, 395 U.S. 486, 496 n.7 

(1969).

CONCLUSION

Accordingly, we grant the petition as to the Knee Replacement Guidance and dismiss the petition as to the 

Knee Replacement Manual Provision and Knee Joint Stability Manual Provision. 

GRANTED-IN-PART, DISMISSED-IN-PART

COSTS

No costs.

Case: 20-1321 Document: 147 Page: 16 Filed: 09/20/2022
United States Court of Appeals 

for the Federal Circuit ______________________ 

NATIONAL ORGANIZATION OF VETERANS' 

ADVOCATES, INC., PETER CIANCHETTA, 

MICHAEL REGIS, ANDREW TANGEN,

Petitioners

v.

SECRETARY OF VETERANS AFFAIRS,

Respondent

______________________ 

2020-1321

______________________ 

Petition for review pursuant to 38 U.S.C. Section 502.

______________________ 

PROST, Circuit Judge, dissenting.

At issue here is the Secretary’s guidance interpreting

diagnostic code 5055 (“DC 5055”) as limited to total knee 

replacements. See 80 Fed. Reg. 42040 (July 16, 2015)

(“Guidance”). The Secretary published the Guidance during a prior appeal, Hudgens v. McDonald, 823 F.3d 630

(Fed. Cir. 2016). There, when urged to apply the Guidance 

retrospectively, we withheld deference under Auer v. Robbins, 519 U.S. 452 (1997), because we concluded that the 

Guidance was a post-hoc rationalization in conflict with 

prior Board decisions. Hudgens, 823 F.3d at 638–39. 

Then, with Auer off the table, we resorted to the pro-veteran canon, which instructs that “interpretive doubt is to 

be resolved in the veteran’s favor,” Brown v. Gardner, 

513 U.S. 115, 118 (1994). Invoking that rule, Hudgens held 

Case: 20-1321 Document: 147 Page: 17 Filed: 09/20/2022
2 NOVA v. SECRETARY OF VETERANS AFFAIRS

for the veteran solely because his interpretation was “permitted by the text of the regulation.” 823 F.3d at 639 (emphasis added). The majority concludes it is compelled to 

follow the same exact path laid out in Hudgens. I disagree. 

And, as I read it, so did Hudgens—which explicitly suggested that going forward the Secretary was free to do what 

he did here. Even if the majority is correct that DC 5055 is 

ambiguous, which I take as given for purposes of this dissent, our two reasons for avoiding Auer in Hudgens do not 

apply here, where we instead confront the Guidance’s prospective application. And the pro-veteran canon does not 

preclude deference here either. I respectfully dissent. 

I 

I begin with Hudgens and my disagreement that it resolves this case. In Hudgens, we found DC 5055 ambiguous. Id. at 637. We withheld Auer deference from the 

Secretary’s interpretation, however, which he published 

during that appeal. Id. at 638. We did so for two reasons, 

both drawn from the Supreme Court’s decision in Christopher v. SmithKline Beecham Corp., 567 U.S. 142, 155 

(2012). Because I conclude that neither of those reasons 

applies in the context of this case, I disagree that Hudgens

precludes us from deferring to the Guidance, and I ultimately conclude that’s what we should do. 

One reason we gave for declining to defer in Hudgens

was that the Guidance was an improper post-hoc rationalization. 823 F.3d at 639. The majority acknowledges, and 

I agree, that this rationale doesn’t apply in the circumstances of this case. Maj. 10. So that pillar of Hudgens is 

gone. 

That “leaves our [other] reason” for withholding deference in Hudgens, Maj. 10—i.e., that the Guidance “conflicts 

with a prior [agency] interpretation.” 823 F.3d at 639 (alteration in original) (quoting Christopher, 567 U.S. at 155). 

More than six years ago, in Hudgens, we looked backwards

and noted that prior Board decisions “favor[ed] 

Case: 20-1321 Document: 147 Page: 18 Filed: 09/20/2022
NOVA v. SECRETARY OF VETERANS AFFAIRS 3

Mr. Hudgens’s view.” Id. “The precise number,” we continued, was “not important.” Id. at 638 n.3. Perhaps it was 

“11 out of 14,” id. at 637, or even “17 out of 21 according to 

[Mr. Hudgens’s] count,” id. at 638 n.3. “What [was] important,” we said, was that these embodied “the vast majority of Board decisions considering the question.” Id. 

The “primary concern” underlying this rationale was 

“the expectations that the agency ha[d] previously engendered.” Maj. 12. That is, “unfair surprise,” upending of 

“reliance,” and lack of “fair warning” ultimately outweighed the reasons to apply Auer. Christopher, 567 U.S. 

at 156–57; see Maj. 12. This remaining pillar of Hudgens, 

the majority believes, still stands. In my view, it doesn’t. 

Specifically, this Hudgens rationale is inapplicable for a 

straightforward reason: in Hudgens, the Secretary tried to 

apply the Guidance retrospectively to Mr. Hudgens’s claim, 

but it now applies only prospectively—signifying both the 

presence of “fair warning” and the absence of “unfair surprise” or upended “reliance” here. As the majority recognizes, the Secretary implemented Hudgens by indicating 

that DC 5055 would cover both partial and total knee replacements for claims filed before the Guidance (like 

Mr. Hudgens’s) but would cover only total knee replacements (per the Guidance) for future claims (like the relevant claims here). Maj. 4. So, where’s the unfair surprise? 

The upending of reliance? The lack of fair warning? There 

is none. 

The majority downplays this distinction and instead 

relies on the same handful of “[d]ecisions issued before the 

[Secretary] promulgated the Guidance,”1 Maj. 13

1 Notably, in view of Kisor v. Wilkie, “Board decisions . . . appear not to be entitled to Auer deference.” Nat’l 

Org. of Veterans’ Advocs., Inc. v. Sec’y of Veterans Affs., 

981 F.3d 1360, 1382 n.14 (Fed. Cir. 2020) (en banc) (citing

139 S. Ct. 2400, 2424 (2019) (stating that the Solicitor 

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4 NOVA v. SECRETARY OF VETERANS AFFAIRS

(emphasis added), which petitioners say “still create the 

conflict today,” Oral Arg. at 10:35–40, No. 20-1321.2 I 

doubt the majority would say that, whenever the Secretary 

corrects a Board interpretation, Auer is forever unavailable; indeed, that position seems contrary to Hudgens itself: 

“If the Secretary is dissatisfied with the Board’s interpretation . . . , the Secretary may instruct the Board regarding 

what the Secretary believes is the correct interpretation.” 

Hudgens, 823 F.3d at 638. 

II

My conclusion above—that neither of the two Auer-defeating rationales of Hudgens applies—leaves me in quite 

a different place from the majority. Because the majority 

calls upon the pro-veteran canon after taking Auer off the 

table, Maj. 15–16, it does not find itself caught between two 

rules that “counsel contrary outcomes.” See Hudgens, 

823 F.3d at 639 n.5. It erroneously avoids that predicament the same way Hudgens did, by deciding there are 

“firm grounds upon which to conclude that Auer deference 

does not apply.” Id. 

Having concluded that those grounds (whatever their 

initial firmness) have given way, however, I do not have the 

same luxury. I must answer the “difficult and unresolved” 

question of which of these two ambiguity-resolving rules 

“gets triggered first”—Auer or the pro-veteran canon. See

Kisor v. McDonough, 995 F.3d 1347, 1358 (Fed. Cir. 2021)

(Prost, C.J., concurring in denial of rehearing en banc) 

General suggested Auer deference may be inappropriate 

for Board decisions)). True, that’s not the issue here, 

Maj. 11, but Kisor at minimum provides reason to question 

the “weight” Hudgens assigned those decisions. Hudgens, 

823 F.3d at 638. 2 https://oralarguments.cafc.uscourts.gov/default.as

px?fl=20-1321_12092021.mp3. 

Case: 20-1321 Document: 147 Page: 20 Filed: 09/20/2022
NOVA v. SECRETARY OF VETERANS AFFAIRS 5

(“Prost Kisor Concurrence”). At least regarding the ambiguity presented in this case, I conclude the answer is Auer. 

I begin with two preliminary points. One, the Supreme 

Court has never applied the pro-veteran canon to a regulation, and Hudgens was the only decision of this court, until 

today, to do so. As I’ve said before, “if the pro-veteran 

canon is based on the theory that it is a proxy for congressional intent, one wonders why it should apply to regulations as well as statutes, or at least whether it would apply 

with equal force.” Prost Kisor Concurrence, 995 F.3d 

at 1349 n.2. Neither Hudgens nor the majority attempts to 

justify why it should so apply. 

Two, even if I agreed with the majority that Auer is off 

the table and the canon is the appropriate tool to employ 

here, the majority’s application of the canon—hinging on 

Hudgens’s statement that the veteran’s interpretation is 

“permitted by the text of the regulation,” is flawed. Maj. 15

(emphasis added) (quoting 823 F.3d at 639). Hudgens, importantly, was decided before the Supreme Court decided 

Kisor v. Wilkie. On remand following the Court’s decision, 

we said the pro-veteran canon “does not apply unless ‘interpretive doubt’ is present,” and that “[t]hat precondition 

is not satisfied where a sole reasonable meaning is identified through the use of ordinary textual analysis tools[] before consideration of the pro-veteran canon.” Kisor v. 

McDonough, 995 F.3d 1316, 1325–26 (Fed. Cir. 2021)

(quoting Brown, 513 U.S. at 117–18), cert. denied, 

142 S. Ct. 756 (2022).3 At the same time, we rejected the 

view that applying the canon is proper so long as the text 

does not “preclude[]” or “expressly exclude the veteran’s interpretation.” See id. at 1336–37 (Reyna, J., dissenting); 

3 The Supreme Court subsequently declined the invitation to address “the appropriate use of the pro-veteran 

canon.” See Petition for Writ of Certiorari at 11, Kisor, 

142 S. Ct. 756 (No. 21-465). 

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6 NOVA v. SECRETARY OF VETERANS AFFAIRS

see also Kisor, 995 F.3d at 1372 (O’Malley, J., dissenting 

from denial of rehearing en banc) (advocating that the 

canon applies “[w]here differing plausible, reasonable interpretations of the terms of a regulation are possible” (emphasis added)). As I’ve said at length elsewhere, we 

shouldn’t apply the pro-veteran canon “merely because a 

veteran-friendly construction is possible.” Prost Kisor Concurrence, 995 F.3d at 1355. 

With those important preliminaries out of the way, I 

conclude for the reasons below that the pro-veteran canon

does not preclude Auer deference here because (A) it is not 

one of the “traditional tools” we must apply before deferring under Auer and (B) resolution of the ambiguity here is 

best understood as delegated to the agency, not the courts. 

A 

In view of the Supreme Court’s instruction that “a 

court must exhaust all the ‘traditional tools’ of construction” before finding ambiguity and deferring under Auer, 

Kisor, 139 S. Ct. at 2415 (cleaned up), I must first consider 

the suggestion that the pro-veteran canon is “one such traditional tool,” Pet’rs’ Br. 35, 44 n.10 (quoting Procopio v. 

Wilkie, 913 F.3d 1371, 1383 (Fed. Cir. 2019) (en banc) 

(O’Malley, J., concurring)); see also Kisor v. Shulkin, 

880 F.3d 1378, 1381 (Fed. Cir. 2018) (O’Malley, J., dissenting from denial of rehearing en banc) (“The [pro-veteran 

canon] is one of those rules of statutory construction.”). I 

conclude it is not. 

Although the Court has not expressly disabused us of 

the notion that the pro-veteran canon is one of the “traditional tools,” it has made clear that not all canons fall 

within this category.4 One example is a similar tiebreaking 

4 Kisor repeatedly describes the “traditional tools” as 

at least including “text, structure, history, and purpose.” 

E.g., 139 S. Ct. at 2415. The Court’s omission of the proCase: 20-1321 Document: 147 Page: 22 Filed: 09/20/2022
NOVA v. SECRETARY OF VETERANS AFFAIRS 7

rule, the rule of lenity. In Yates v. United States, the Court 

stated that “[f]inally, if our recourse to traditional tools of 

statutory construction leaves any doubt . . . , we would invoke the rule that ambiguity concerning the ambit of criminal statutes should be resolved in favor of lenity.” 

574 U.S. 528, 547–48 (2015) (cleaned up). And more recently in Shular v. United States, the Court explained that 

lenity “applies only when, after consulting traditional canons of statutory construction, we are left with an ambiguous statute.” 140 S. Ct. 779, 787 (2020). As I’ve observed, 

the Supreme Court’s invocation of the pro-veteran canon 

across its “relatively short” history—typically just to “further confirm an interpretation that [the Court] reached by 

analyzing text and context”— resembles the rule of lenity 

and reflects this same order of operations. See Prost Kisor

Concurrence, 995 F.3d at 1350–55.5

The pro-veteran canon’s normative character also supports my conclusion that it is not one of the contemplated 

“traditional tools.” Descriptive canons, like the traditional 

tools mentioned in Kisor, “are just specific applications of 

the basic goal of interpretation: finding the ordinary 

veteran canon from this list might be unremarkable except 

that one of the two questions presented in Kisor at the certiorari stage was whether Auer should yield to the pro-veteran canon. The Court did not grant certiorari on that 

question. 

5 A different (and more dubious) conception of the 

pro-veteran canon is not as a tiebreaking rule, but as a 

broad liberal-construction principle. Prost Kisor Concurrence, 995 F.3d at 1351–54. This view ignores that “[l]egislation is . . . the art of compromise, the limitations 

expressed in statutory terms [are] often the price of passage, and no statute yet known pursues its stated purpose 

at all costs.” Henson v. Santander Consumer USA Inc., 

137 S. Ct. 1718, 1725 (2017) (cleaned up). 

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8 NOVA v. SECRETARY OF VETERANS AFFAIRS

meaning of statutory text.” Arangure v. Whitaker, 911 F.3d 

333, 340 (6th Cir. 2018). But the pro-veteran canon is a 

substantive canon that “enter[s] the calculus when judges 

‘need some way to finish the job and to pick from among 

the possible meanings that their primary interpretive tools 

have identified.’” Prost Kisor Concurrence, 995 F.3d 

at 1350 (quoting Caleb Nelson, What Is Textualism?, 

91 Va. L. Rev. 347, 394 (2005)); see also Vitol, Inc. v. United 

States, 30 F.4th 248, 253 (5th Cir. 2022) (“[O]nly . . . after 

plain meaning and application of the interpretive canons 

are found lacking . . . do the so-called substantive canons

. . . come into play.” (cleaned up)). They “express the law’s 

supposed preferences when certain close interpretive calls 

arise.” Calderon v. Sixt Rent a Car, LLC, 5 F.4th 1204, 

1219 (11th Cir. 2021) (Newsom, J., concurring). Accordingly, “[a]mbiguity canons merely instruct courts on how to 

‘choos[e] between equally plausible interpretations of ambiguous text.’” W. Virginia v. EPA, 142 S. Ct. 2587, 2620 

n.3 (2022) (Gorsuch, J., concurring) (second alteration in 

original) (quoting Amy Coney Barrett, Substantive Canons 

and Faithful Agency, 90 B.U. L. Rev. 109, 109 (2010)). Any 

other role makes no sense “as a logical matter.” Prost Kisor

Concurrence, 995 F.3d at 1354. “[I]f ‘interpretive doubt’ is 

a precondition for applying the canon,” then “the existence 

of interpretive doubt must be determined without employing the canon.” Id. “Otherwise, circularity results.” Id. 

For these reasons, the pro-veteran canon is not one of 

the “traditional tools” we must apply before concluding that 

a regulation is ambiguous. Rather, it kicks in after a conclusion of ambiguity—similar to the way lenity, Chevron, 

Auer, and other ambiguity-triggered rules do.6 

6 Concluding otherwise would mean “the VA, alone 

among the executive agencies, is not entitled to deference 

in interpreting its regulations,” which “would be 

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NOVA v. SECRETARY OF VETERANS AFFAIRS 9

B 

Having concluded that the pro-veteran canon need not 

be applied before finding ambiguity and applying Auer, I 

also conclude that Auer provides the proper resolution of

the ambiguity in this case. In my view, deciding which rule 

applies here requires recognizing that “ambiguity is essentially a delegation of policymaking authority to the governmental actor charged with interpreting” the relevant 

provision, and that the pro-veteran canon and Auer deference are each a type of delegation—just to different actors. 

See Barrett, supra, at 123. Like Chevron deference, which

“treat[s] statutory ambiguity as a delegation of gap-filling 

authority to an administrative agency,” id. at 182 n.66, 

Auer deference is similarly “rooted in a presumption about 

congressional intent,” i.e., “that Congress would generally 

want the agency to play the primary role in resolving regulatory ambiguities,” Kisor, 139 S. Ct. at 2412, as well as

an “awareness that resolving genuine regulatory ambiguities often entails the exercise of judgment grounded in policy concerns,” id. at 2413 (cleaned up). “[T]he core theory 

of Auer deference is that sometimes the law runs out, and 

policy-laden choice is what is left over.” Id. at 2415. 

In a similar vein, “a judge applying a canon like lenity”—or the pro-veteran canon—“to implement unclear text 

is not deviating from her best understanding of Congress’s 

instructions”—that “Congress left the problem to her.” See

Barrett, supra, at 123. Accordingly, “we presume[] Congress intended to invest interpretive power in whichever 

actor was best positioned to develop expertise about the

given problem,” Kisor, 139 S. Ct. at 2417 (cleaned up), including “as between agencies and courts,” id. 

anomalous to say the least.” Kisor, 995 F.3d at 1361 

(Hughes, J., concurring in denial of rehearing en banc). 

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10 NOVA v. SECRETARY OF VETERANS AFFAIRS

Here, the ambiguity is in a gap-filling regulation on a 

matter well within the agency’s expertise: the coverage of 

a medical diagnostic code. See id. at 2413 (“Agencies (unlike courts) have unique expertise, often of a scientific or 

technical nature, relevant to applying a regulation to complex or changing circumstances.” (cleaned up)). Specifically, DC 5055 sets forth ratings for knee replacements as 

a subsection of 38 C.F.R. § 4.71a. That regulation, in turn, 

is authorized by 38 U.S.C. § 1155, which broadly instructs 

that “[t]he Secretary shall adopt and apply a schedule of 

ratings of reductions in earning capacity from specific injuries or combination of injuries.” And the Secretary’s explanation for his interpretation is “[t]he progression of this 

area of medical science.” J.A. 1.7 

Conceivably, some regulatory ambiguities might be 

better resolved by courts applying the pro-veteran canon. 

Perhaps, for example, “[w]hen the agency has no comparative expertise in resolving a regulatory ambiguity,” since in 

such a case “Congress presumably would not grant it that 

authority.” Kisor, 139 S. Ct. at 2417 (indicating that 

“[s]ome interpretive issues,” like “the elucidation of a simple common-law property term” or “the award of an attorney’s fee,” “may fall more naturally into a judge’s 

bailiwick”). But that’s not what we have here. Rather, the 

most logical conclusion is that Congress delegated resolution of the ambiguity here to the agency, which must “fill 

7 “The field of orthopedic medicine has progressed to 

such a degree that total prosthetic replacement of a joint is 

not always necessary. . . . Partial replacement has the benefit of not requiring the same length of time for convalescence. The progression of this area of medical science has 

raised an issue as to whether a veteran who undergoes a 

partial replacement of a joint is entitled to the 100-percent 

rating evaluation during the convalescent period under 

DCs 5051 through 5056.” J.A. 1 (footnote omitted). 

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NOVA v. SECRETARY OF VETERANS AFFAIRS 11

out the regulatory scheme Congress has placed under its 

supervision.” Id. at 2418. Indeed, we’ve deferred for similar reasons in the closely related Chevron context. In Buffington v. McDonough, for example, we did so where the 

Secretary “filled a statutory gap.” 7 F.4th 1361, 1367 

(Fed. Cir. 2021). There, we also declined to apply the proveteran canon. Compare id. at 1366 n.5, with id.

at 1374–75 (O’Malley, J., dissenting). Likewise in Terry v. 

Principi we deferred under Chevron to fill a gap instead of 

applying the pro-veteran canon. 340 F.3d 1378, 1383 

(Fed. Cir. 2003). Accordingly, the ambiguity in this case 

implicates the rationales underlying Auer, not the pro-veteran canon. 

III

The Guidance we review here is a forward-looking prescription, not a post-hoc rationalization or a reliance-upending departure from a prior agency position. With Auer

still on the books after Kisor, we must defer to it absent any 

other applicable exceptions. Nothing in Hudgens prevents 

us from doing so in this case. I respectfully dissent. 

Case: 20-1321 Document: 147 Page: 27 Filed: 09/20/2022