Court Opinion

ID: 9840120
Source: CourtListenerOpinion
Date Created: 2023-09-15 14:01:00.765619+00
Date Added: 2024-06-11T10:10:28.464526
License: Public Domain

Case: 21-2299    Document: 61     Page: 1   Filed: 09/15/2023

   United States Court of Appeals
       for the Federal Circuit
                  ______________________

   COLUMBIA SPORTSWEAR NORTH AMERICA,
                     INC.,
              Plaintiff-Appellant

                             v.

     SEIRUS INNOVATIVE ACCESSORIES, INC.,
             Defendant-Cross-Appellant
              ______________________

                   2021-2299, 2021-2338
                  ______________________

    Appeals from the United States District Court for the
 Southern District of California in No. 3:17-cv-01781-HZ,
 Judge Marco A. Hernandez.
                 ______________________

                Decided: September 15, 2023
                  ______________________

     NICHOLAS FREMONT ALDRICH, JR., Schwabe, William-
 son & Wyatt P.C., Portland, OR, argued for plaintiff-appel-
 lant. Also represented by SCOTT D. EADS, SARA KOBAK. Also
 argued by CHRISTOPHER V. CARANI, McAndrews, Held &
 Malloy, Ltd., Chicago, IL.

     SETH MCCARTHY SPROUL, Fish & Richardson, P.C., San
 Diego, CA, argued for defendant-cross-appellant. Also rep-
 resented by CHRISTOPHER MARCHESE, JOHN WINSTON
 THORNBURGH.
                 ______________________
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 2              COLUMBIA SPORTSWEAR NORTH AMERICA, INC. v.
                       SEIRUS INNOVATIVE ACCESSORIES, INC.

     Before PROST, REYNA, and HUGHES, Circuit Judges.
 PROST, Circuit Judge.
     Columbia Sportswear North America, Inc. (“Colum-
 bia”) sued Seirus Innovative Accessories, Inc. (“Seirus”) for
 infringing U.S. Design Patent No. D657,093 (“the D’093 pa-
 tent”). After the district court granted summary judgment
 of infringement and a jury awarded Columbia $3,018,174
 in damages, Seirus appealed to this court. In Columbia I, 1
 we vacated the summary judgment of infringement and re-
 manded for further proceedings.
     On remand, a jury found that Seirus did not infringe.
 Columbia appeals, mainly challenging the jury instruc-
 tions. Seirus conditionally cross-appeals as to damages.
 For the reasons discussed below, we vacate the non-in-
 fringement judgment and remand for further proceedings.
                         BACKGROUND
                               I
      Columbia’s D’093 patent, titled “Heat Reflective Mate-
 rial,” claims “[t]he ornamental design of a heat reflective
 material, as shown and described” in various figures.
 D’093 patent, at [54], [57]. Figure 1, described as “an ele-
 vational view of a heat reflective material,” J.A. 4, is repro-
 duced below:

     1   Columbia Sportswear N. Am., Inc. v. Seirus Inno-
 vative Accessories, Inc., 942 F.3d 1119 (Fed. Cir. 2019) (“Co-
 lumbia I”).
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 J.A. 1704.
     Seirus markets and sells products (e.g., gloves) made
 with material that it calls HeatWave. An image of Heat-
 Wave material appears below:

 Cross-Appellant’s Br. 17 (citing J.A. 3992).
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                              II
                              A
     Columbia sued Seirus in district court, 2 accusing
 Seirus of infringing the D’093 patent via its HeatWave
 products.
      Columbia sought both a construction of the D’093 pa-
 tent’s claim and summary judgment of infringement. The
 district court declined to construe the claim but granted
 summary judgment of infringement all the same. Colum-
 bia Sportswear N. Am., Inc. v. Seirus Innovative Accesso-
 ries, 202 F. Supp. 3d 1186, 1189 (D. Or. 2016) (“SJ
 Opinion”).
      The district court’s summary-judgment opinion began
 with the “ordinary observer” test for design-patent in-
 fringement, drawn from the Supreme Court’s Gorham de-
 cision:
     [I]f, in the eye of an ordinary observer, giving such
     attention as a purchaser usually gives, two designs
     are substantially the same, if the resemblance is
     such as to deceive such an observer, inducing him
     to purchase one supposing it to be the other, the
     first one patented is infringed by the other.

     2   Columbia sued in the U.S. District Court for the
 District of Oregon, which later transferred the case to the
 U.S. District Court for the Southern District of California,
 from which it came to this court on appeal in Columbia I
 and comes again to this court now. See Columbia I,
 942 F.3d at 1124, 1132–33. Because the distinction is im-
 material to our discussion, we refer to the two district
 courts interchangeably as the district court.
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 SJ Opinion, 202 F. Supp. 3d at 1190–91 (alteration in orig-
 inal) (quoting Gorham Co. v. White, 81 U.S. (14 Wall.) 511,
 528 (1871)).
     The district court also addressed the topic of compari-
 son prior art. In a design-patent infringement analysis,
 comparison prior art serves as background when compar-
 ing a claimed and accused design. See id. at 1195 (stating
 that the “ordinary observer is deemed to view the differ-
 ences between the patented design and the accused product
 in the context of the prior art,” and “when the claimed de-
 sign is close to the prior art designs, small differences be-
 tween the accused design and the claimed design are likely
 to be important to the eye of the hypothetical ordinary ob-
 server” (quoting Egyptian Goddess, Inc. v. Swisa, Inc.,
 543 F.3d 665, 676 (Fed. Cir. 2008) (en banc))).
      The district court then discussed two issues relevant
 here. First, it rejected Seirus’s argument that the Seirus
 logo appearing throughout the design of HeatWave mate-
 rial made that design different enough from the claimed
 design to preclude summary judgment of infringement. Id.
 at 1193–94. Indeed, relying on its interpretation of this
 court’s precedent, the district court disregarded the Seirus
 logo altogether in its infringement analysis. Id. at 1193
 (citing L.A. Gear, Inc. v. Thom McAn Shoe Co., 988 F.2d
 1117, 1126 (Fed. Cir. 1993)). Second, the district court
 evaluated the comparison prior art that Seirus had offered
 in support of its non-infringement position. As to U.S. Pa-
 tent Nos. 2,539,690 (“Boorn”) and 1,515,792 (“Respess”),
 the district court found that they “cover[ed] products far
 afield” from the D’093 patent’s heat reflective material and
 therefore were not relevant comparison prior art. See id.
 at 1196. As to U.S. Patent No. 5,626,949 (“Blauer”), how-
 ever, the district court compared it side-by-side with both
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                       SEIRUS INNOVATIVE ACCESSORIES, INC.

 the D’093 patent and the HeatWave material (as shown be-
 low, with Blauer listed as the ’949 patent):

 Id. at 1197. The district court found that “the contrasting
 waves of Seirus’s design are still substantially closer to the
 contrasting wave design disclosed in the D’093 patent than
 either Seirus’s or Columbia’s design is to the pattern dis-
 closed in [Blauer].” Id. (finding that “[t]he waves in
 [Blauer] are not contrasting colors” and that “the waves in
 the Columbia and Seirus designs are very close to the same
 wavelength and amplitude”). In light of this evaluation,
 the district court found that “[t]he overall visual effect of
 the Columbia and Seirus designs [is] nearly identical.” Id.
     With infringement thus established, damages were
 tried to a jury, who awarded Columbia $3,018,174.
                               B
      Seirus appealed the district court’s summary judgment
 of infringement and the jury’s damages award to this court.
 In Columbia I, we vacated the summary judgment, con-
 cluding that the district court erred in two respects.
      First, the district court had improperly declined to con-
 sider the effect of Seirus’s logo in its infringement analysis.
 Columbia I, 942 F.3d at 1130. We explained that, while a
 “would-be infringer should not escape liability for design
 patent infringement if a design is copied but labeled with
 its name,” our precedent “does not prohibit the fact finder
 from considering an ornamental logo, its placement, and its
 appearance as one among other potential differences be-
 tween a patented design and an accused one.” See id.
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 at 1131 (emphasis in original). Second, the district court
 had resolved certain fact issues that should have been left
 to a jury. Among these issues was the impact of Seirus’s
 comparison prior art. In particular, after we described the
 district court’s three-way comparison of the D’093 patent,
 the Seirus HeatWave material, and Blauer—as well as the
 court’s resulting finding that “[t]he overall visual effect of
 the Columbia and Seirus designs [is] nearly identical”—we
 concluded that this factfinding was improper on summary
 judgment. Id. (first alteration in original) (quoting SJ
 Opinion, 202 F. Supp. 3d at 1197).
     We therefore vacated the summary judgment and re-
 manded for further proceedings. Although we noted
 Seirus’s separate arguments concerning damages, we
 “d[id] not reach them because we ha[d] vacated the in-
 fringement finding.” Id. at 1132.
                              III
     Infringement was then tried to a jury. Three aspects
 of that trial are relevant here: (1) the comparison prior art
 (and related arguments), (2) the jury instructions on com-
 parison prior art, and (3) the jury instructions implicating
 the Seirus logo. We discuss each in turn.
                               A
     Before trial, the district court limited admissible com-
 parison prior art to “wave patterns on fabric.” J.A. 421
 (emphasis added). In light of this ruling, Seirus presented
 to the jury Boorn, Respess, and Blauer as alleged compari-
 son prior art.
      Boorn is a 1951 utility patent that discloses a method
 of inlaying plastic threads into plastic sheets. In particu-
 lar, it says that prior-art methods of simply painting,
 stamping, or printing ornamental stripes on the surface of
 a coated fabric or a plastic sheet produce stripes that are
 “likely to wear off readily,” and it seeks to overcome that
 problem by “forcing into such surface preformed plastic
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 8              COLUMBIA SPORTSWEAR NORTH AMERICA, INC. v.
                       SEIRUS INNOVATIVE ACCESSORIES, INC.

 threads or ribbons to thereby embed them in the surface of
 the plastic material and form the desired inlaid striped de-
 sign.” J.A. 1465 col. 1 ll. 1–19.
     Respess is a 1924 utility patent that discloses a “pro-
 cess of making a strong pliable unwoven fabric.” See
 J.A. 1468 col. 1 ll. 13–14. One of the objects of the inven-
 tion is to make such a fabric so that it “may readily be
 formed around the core in making a rubber tire and similar
 articles.” J.A. 1468 col. 1 ll. 22–29.
     Blauer is a 1997 utility patent titled “Breathable Shell
 for Outerwear.” J.A. 1457. It describes its “Field of the
 Invention” as “relat[ing] to fabric constructions for outer-
 wear, and, more particularly, to shell fabric constructions
 for coats, pants, jackets, boots, gloves, and other outer
 clothing that are designed for protection against inclement
 weather.” J.A. 1460 col. 1 ll. 10–15. Its outerwear shell
 seeks to achieve “vapor permeability, water repellency,
 wind obstruction, stain resistance, dimensional stability,
 and external durability.” J.A. 1460 col. 2 ll. 1–8.
      The district court, in addition to admitting these refer-
 ences because they disclosed fabric, precluded Columbia
 from trying to distinguish them as not disclosing heat re-
 flective material. The district court reasoned that allowing
 Columbia to do so (e.g., by argument or witness question-
 ing) would improperly import functional considerations
 into the design-patent infringement analysis. See J.A. 421.
                               B
      Columbia proposed two jury instructions addressing
 the proper scope of comparison prior art. Proposed jury in-
 struction no. 9E (titled “Claim Scope”) stated that “[t]he
 [D’093 patent] is limited to the design of heat reflective ma-
 terials, as shown and described in the patent,” and that
 “[t]he plain and ordinary meaning of ‘heat reflective mate-
 rials’ in the context of the [D’093 patent] does not include
 all materials.”     J.A. 360 (capitalization normalized).
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 Proposed jury instruction no. 9F (titled “What is Prior Art”)
 stated:
     In design patent law, the term “prior art” refers to
     prior designs that address the same subject matter
     or field of endeavor as the patented design or that
     address a field of endeavor so similar that a de-
     signer having ordinary skill would look to articles
     in that field for their designs. The subject matter
     and field of endeavor of the D’093 patent is orna-
     mental designs for heat reflective materials.
 J.A. 369 (capitalization normalized).
      During trial, the district court gave the parties a draft
 of its jury instructions. Columbia took issue with the dis-
 trict court’s draft instruction no. 11, which concerned com-
 parison prior art. Columbia argued that (1) the scope of
 comparison prior art “is not the universe of abstract design
 but is limited to designs of the same article of manufacture
 or of articles so similar that a person of ordinary skill would
 look to such articles for their designs,” and (2) at the very
 least, the jury (as fact finder) should get to decide for them-
 selves whether Boorn, Respess, and Blauer were within the
 proper scope. See J.A. 1172–73 (cleaned up). The district
 court then invited the parties to propose revisions to its
 draft jury instructions. J.A. 1185. Columbia proposed in-
 cluding a sentence in draft instruction no. 11 stating: “The
 term ‘prior art’ refers to prior designs of the same article of
 manufacture or of articles so similar that a person of ordi-
 nary skill would look to such articles for their designs.”
 J.A. 1481.
     The district court declined to include Columbia’s pro-
 posed sentence and gave instruction no. 11 (in relevant
 part) to the jury as follows:
     You must decide what is prior art. Prior art in-
     cludes things that were publicly known, or used in
     a publicly accessible way in this country, or that
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      were patented or described in a publication in any
      country before the creation of the claimed design.
      You must familiarize yourself with the prior art in
      determining whether there has been infringement.
      When the claimed design is visually close to prior
      art designs, small differences between the accused
      design and the claimed design may be important in
      analyzing whether the overall appearances of the
      accused and claimed designs are substantially the
      same.
 J.A. 1521.
     Thus, aside from publication and date requirements—
 matters undisputed as to Boorn, Respess, and Blauer—the
 jury instructions provided no standard by which the jury
 should decide what is comparison prior art.
                               C
     Columbia also proposed two jury instructions address-
 ing Seirus’s logo on the accused HeatWave design. Pro-
 posed jury instruction no. 9B (titled “Design Patent
 Infringement”) stated that “[c]onfusion as to the source or
 provider of the goods accused of infringing is irrelevant to
 determining whether a patent is infringed.” J.A. 348. Pro-
 posed jury instruction no. 9D (titled “Logo/Confusion”)
 stated:
      Labelling a product with source identification or
      branding does not avoid infringement. Consumer
      confusion as to the source or provider of the prod-
      ucts is not a consideration in an infringement anal-
      ysis. [B]ut you may consider an ornamental logo,
      its placement, and its appearance as one among
      other potential differences between a patented de-
      sign and an accused one in deciding whether the
      overall appearance of the patented and accused de-
      sign are substantially similar.
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 J.A. 356.
     The district court’s draft jury instructions did not in-
 clude Columbia’s proposals (at least not verbatim). See Ap-
 pellant’s Br. 37–38. Instead, draft instruction no. 10 did
 two basic things. First, it recited the ordinary-observer
 test: “Two designs are substantially the same if, in the eye
 of an ordinary observer, giving such attention as a pur-
 chaser usually gives, the resemblance between the two de-
 signs is such as to deceive an ordinary observer, inducing
 him to purchase one supposing it to be the other.” Appel-
 lant’s Br. 38; see Gorham, 81 U.S. at 528. Second, it added:
 “You do not need, however, to find that any purchasers
 were actually deceived or confused by the appearance of the
 accused products.” Appellant’s Br. 38.
     Columbia took issue with the district court’s draft in-
 struction no. 10, arguing that it should have added that the
 jury also need not find a likelihood of consumer confusion.
 J.A. 1159–60. Columbia proposed revising a sentence in
 the instruction to state: “You do not need, however, to find
 that any purchasers were actually deceived, nor do you
 need to find any actual confusion or likelihood of confusion
 amongst consumers in the marketplace.” J.A. 1481 (em-
 phasis added). The district court declined to include Co-
 lumbia’s proposed revision and instead gave instruction
 no. 10 (in relevant part) to the jury as follows:
     Two designs are substantially the same if, in the
     eye of an ordinary observer, giving such attention
     as a purchaser usually gives, the resemblance be-
     tween the two designs is such as to deceive an or-
     dinary observer, inducing him to purchase one
     supposing it to be the other. You do not need, how-
     ever, to find that any purchasers were actually de-
     ceived or confused by the appearance of the accused
     products.
 J.A. 1520.
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                          *   *    *
     The jury returned a verdict of non-infringement, and
 the district court accordingly entered judgment for Seirus.
 Columbia appeals, and Seirus conditionally cross-appeals
 as to damages. We have jurisdiction under 28 U.S.C.
 § 1295(a)(1).
                         DISCUSSION
     Our discussion proceeds as follows. Part I addresses
 the parties’ arguments concerning the preclusive effects of
 prior proceedings. Parts II.A and II.B address Columbia’s
 jury-instruction and other challenges concerning compari-
 son prior art and Seirus’s logo. Part III addresses Seirus’s
 conditional cross-appeal.
                               I
     The parties argue that prior proceedings through Co-
 lumbia I create certain preclusive effects here. These ef-
 fects take various labels. Both parties invoke law of the
 case, while Seirus adds judicial estoppel to the mix. We
 reject each of these contentions.
     The law-of-the-case doctrine relies on the force of a
 matter having already been decided in the case. See, e.g.,
 Christianson v. Colt Indus. Operating Corp., 486 U.S. 800,
 817 (1988) (noting that the doctrine “expresses the practice
 of courts generally to refuse to reopen what has been de-
 cided” (cleaned up)). Columbia, citing the district court’s
 previous exclusion of comparison prior art concerning prod-
 ucts “far afield” from heat reflective material, argues that
 this ruling as to what qualifies as comparison prior art be-
 came the law of the case when Seirus failed to challenge it
 in Columbia I. Appellant’s Br. 55–56 (citing SJ Opinion,
 202 F. Supp. 3d at 1196 (excluding Boorn and Respess from
 consideration as comparison prior art)). Seirus does not
 dispute that it failed to challenge that particular ruling in
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 Columbia I. 3 Instead, it maintains that, because Colum-
 bia I vacated the summary judgment, that ruling cannot be
 relied upon as law of the case. Cross-Appellant’s Br. 48–49
 (citing Rumsfeld v. Freedom NY, Inc., 329 F.3d 1320, 1332
 (Fed. Cir. 2003) (“[A] vacated judgment has no preclusive
 force . . . as a matter of the law of the case.” (cleaned up))).
     Columbia’s argument, however, does not implicate law
 of the case so much as it does forfeiture 4—a related, yet
 distinct, concept in this area. See, e.g., Crocker v. Piedmont
 Aviation, Inc., 49 F.3d 735, 739 (D.C. Cir. 1995) (noting

     3    To be sure, Seirus challenged the district court’s
 comparison of the claimed and accused designs with Blauer
 as resulting in factual determinations improperly made
 against it at summary judgment. But it did not challenge
 how the district court decided which comparison prior art
 to consider in the first place. Unsurprisingly, given
 Seirus’s failure to raise that issue, Columbia I did not pass
 upon it. That being so, Seirus’s statements throughout its
 briefing that Columbia I reversed the district court on “ex-
 actly th[at] issue[],” Cross-Appellant’s Br. 12—or that Co-
 lumbia’s position in this appeal regarding comparison prior
 art is “directly contrary to this [c]ourt’s decision in Colum-
 bia I,” id. at 38, 42 (emphasis added)—are inaccurate (at
 best).
     4    Although Columbia’s briefing and several authori-
 ties on this issue use the term “waiver,” we believe “forfei-
 ture” is more accurate. See 18B Charles Alan Wright,
 Arthur R. Miller & Edward H. Cooper, Federal Practice
 and Procedure § 4478.6, pp. 786, 791–92 (3d ed. 2019) (ob-
 serving in this area that, “[a]lthough forfeiture would be a
 more suitable expression,” that term “is not always used;
 waiver often takes its place”); see also In re Google Tech.
 Holdings LLC, 980 F.3d 858, 862–63 (Fed. Cir. 2020) (ex-
 plaining that courts and litigants often use the term
 “waiver” when applying the doctrine of forfeiture).
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 that the bar on litigating issues “omitted from prior ap-
 peals” is “best understood as a species of waiver doctrine”
 and is “analytically distinct” from “law-of-the-case doctrine
 proper”); id. at 739–40; see also 18B Wright & Miller
 § 4478.6 (distinguishing between law of the case and forfei-
 ture). The argument is that Seirus’s failure to challenge
 the district court’s scope-of-comparison-prior-art ruling in
 Columbia I cemented that ruling as, essentially, the law of
 the case. Viewed that way, it is unclear why our disposition
 in Columbia I would relieve Seirus of the consequences of
 its failure to challenge that particular ruling—at least
 given that, aside from recounting the ruling as background,
 Columbia I, 942 F.3d at 1130, our disposition neither ad-
 dressed it nor necessarily disturbed it.
     Still, whether to excuse a forfeiture is generally within
 our discretion. See, e.g., Arthrex, Inc. v. Smith & Nephew,
 Inc., 35 F.4th 1328, 1344 n.7 (Fed. Cir. 2022). And here,
 the circumstances counsel against letting Seirus’s forfei-
 ture dictate what qualifies as comparison prior art.
 Seirus’s forfeiture could fairly cover only the district court’s
 ruling as applied to Boorn and Respess (references the
 court excluded from consideration). The district court con-
 sidered Blauer extensively, so Seirus had no occasion to
 challenge the ruling as applied to Blauer. See United
 States v. Lee, 358 F.3d 315, 324 (5th Cir. 2004) (“An issue
 is not waived if there was no reason to raise it in the initial
 appeal.”). And, because Blauer persisted as potential com-
 parison prior art in the infringement trial, Columbia’s cur-
 rent appeal would in any event require us to articulate the
 proper scope of comparison prior art—an issue of first im-
 pression for this court. See infra Discussion Part II.A. Be-
 cause we are just now articulating this scope, we deem it
 the better course to allow the parties and the district court
 to engage with it afresh—both as to Blauer and other ref-
 erences. Cf. Crocker, 49 F.3d at 740 (noting that an inter-
 vening change in the law will support departing from the
 “previously established law of the case” and that “[t]he
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 preclusive barrier of the waiver doctrine is even one notch
 weaker”).
      Seirus, for its part, likewise invokes law of the case, al-
 beit likewise in a way that implicates forfeiture. According
 to Seirus, when Columbia failed to challenge (in Colum-
 bia I) the district court’s decision not to construe the claim,
 it forfeited the ability to seek a claim construction—thus
 cementing a non-construction as the law of the case and
 barring Columbia from arguing about what a heat reflec-
 tive material is. See Cross-Appellant’s Br. 47–48 (arguing
 that Columbia’s proposed jury instruction—that heat re-
 flective materials not mean all materials—is improper due
 to that alleged forfeiture).
     We reject Seirus’s argument. Insofar as Columbia I
 concerned the D’093 patent, 5 Columbia came to this court
 as the appellee, having prevailed on infringement. We
 therefore do not see—nor has Seirus supplied—any reason
 why Columbia should have quibbled with the district
 court’s decision not to construe the claim. See Laitram
 Corp. v. NEC Corp., 115 F.3d 947, 954 (Fed. Cir. 1997) (dis-
 tinguishing between applying “waiver” as against a prior
 appellant and appellee and noting that the issue was “not
 what [appellee] could supposedly have argued [in the prior
 appeal], but rather what it was required to argue, or indeed
 could properly have argued” (emphasis in original)); see
 also Yesudian ex rel. United States v. Howard Univ.,
 270 F.3d 969, 971 (D.C. Cir. 2001) (“[A]ny forfeiture from
 failure to raise an issue in an initial appeal is far from ab-
 solute, especially where . . . the party failing to present the
 issue was the appellee, defending on a field of battle de-
 fined by the appellant.”). Accordingly, there was no forfei-
 ture here, and therefore nothing amounting to a “law of the

     5   Columbia I also concerned a Columbia utility pa-
 tent that is no longer at issue.
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 case” foreclosing a claim construction or related argu-
 ments.
      Finally, Seirus argues that Columbia should be judi-
 cially estopped from maintaining that the relevant article
 of manufacture—for purposes of infringement-related com-
 parison prior art—is heat reflective material. See Cross-
 Appellant’s Br. 47. Seirus argues that such a position
 would be inconsistent with Columbia’s position at the dam-
 ages trial that the relevant “article of manufacture”—for
 purposes of calculating damages under 35 U.S.C. § 289—is
 an entire end product (e.g., gloves with portions not made
 of HeatWave material).
      We disagree that judicial estoppel is appropriate here.
 Judicial estoppel “is an equitable doctrine invoked by a
 court at its discretion.” New Hampshire v. Maine, 532 U.S.
 742, 750 (2001) (cleaned up). Factors that typically inform
 whether to apply the doctrine include: (1) whether a party’s
 earlier and later positions are “clearly inconsistent”;
 (2) whether the party “succeeded in persuading a court to
 accept” the earlier position; and (3) whether the party
 would “derive an unfair advantage or impose an unfair det-
 riment” on the opposing party if not estopped. Id.
 at 750–51 (cleaned up). Setting aside whether Columbia’s
 positions are “clearly inconsistent”—an issue we do not
 reach in this case, cf. infra Discussion Part III (declining to
 reach Seirus’s damages issues on the merits)—judicial es-
 toppel is an equitable doctrine. And we see no equity in
 letting a position Columbia took while securing a (cur-
 rently inapplicable) damages award impede its efforts to
 secure infringement liability—and thus damages—at all.
 Any incompatibility between a determination of infringe-
 ment and the previously determined damages award may
 be addressed, if at all, if Columbia prevails on infringe-
 ment.
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                               II
     We turn now to Columbia’s challenges to (1) the jury
 instructions (and exclusion of evidence and argument) con-
 cerning comparison prior art and (2) the jury instructions
 implicating Seirus’s logo.
      The parties agree that we should review Columbia’s
 jury-instruction challenges under the law of the regional
 circuit—here, the Ninth Circuit. Appellant’s Br. 46 (citing
 Voda v. Cordis Corp., 536 F.3d 1311, 1328 (Fed. Cir. 2008));
 Cross-Appellant’s Br. 40 (same). We also applied Ninth
 Circuit law in reviewing a jury-instruction challenge in Co-
 lumbia I. 942 F.3d at 1127–28. We do so again here. That
 means we “review de novo whether an instruction states
 the law correctly” and review for abuse of discretion “a dis-
 trict court’s formulation of civil jury instructions.” Peralta
 v. Dillard, 744 F.3d 1076, 1082 (9th Cir. 2014) (en banc);
 id. (noting further that jury instructions must “fairly and
 adequately cover the issues presented, correctly state the
 law, and not be misleading”); see also Gantt v. City of L.A.,
 717 F.3d 702, 706 (9th Cir. 2013) (“Incomplete instructions
 are treated as legal errors and reviewed de novo as well.”). 6

     6    We acknowledge precedent “apply[ing] Federal
 Circuit law to review the legal sufficiency of jury instruc-
 tions on an issue of patent law without deference to the dis-
 trict court.” Eko Brands, LLC v. Adrian Rivera Maynez
 Enters., Inc., 946 F.3d 1367, 1378 (Fed. Cir. 2020) (cleaned
 up); see id. at 1378 & n.4 (asking whether instructions were
 “incomplete as given” and whether they “correctly state[d]
 an issue of patent law” (cleaned up)); see also DSU Med.
 Corp. v. JMS Co., 471 F.3d 1293, 1304 (Fed. Cir. 2006) (en
 banc in relevant part) (“This [c]ourt . . . only orders a new
 trial when errors in the instructions as a whole clearly mis-
 lead the jury.” (cleaned up)). Ultimately, which standard—
 the Ninth Circuit’s or ours—governs here is immaterial
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     We review the district court’s exclusion of evidence or
 argument at trial under the law of the regional circuit. See
 Star Sci., Inc. v. R.J. Reynolds Tobacco Co., 655 F.3d 1364,
 1372 (Fed. Cir. 2011). The Ninth Circuit reviews such rul-
 ings for abuse of discretion. See Wagner v. Cnty. of Mari-
 copa, 747 F.3d 1048, 1052 (9th Cir. 2013) (evidence); U.S.
 Fid. & Guar. Co. v. Lee Invs. LLC, 641 F.3d 1126, 1137
 (9th Cir. 2011) (argument).
     We first address the comparison-prior-art issues, then
 the logo issues.
                              A
                              1
     We begin with the purpose of comparison prior art in a
 design-patent infringement analysis. 7
     Before our en banc opinion in Egyptian Goddess, de-
 sign-patent infringement required satisfying two separate
 tests. One was the ordinary-observer test. Egyptian God-
 dess, 543 F.3d at 670–72 (citing Gorham, 81 U.S. at 528).
 The other was the “point of novelty” test, which asked
 whether the similarity between the claimed and accused
 designs was attributable to the novelty that distinguished

 because our conclusions would be the same under either
 standard. See ADASA Inc. v. Avery Dennison Corp.,
 55 F.4th 900, 914 (Fed. Cir. 2022) (declining to resolve
 which standard of review for jury instructions applies
 when either would produce the same result).
     7    Using prior art in an infringement analysis is, by
 and large, peculiar to design-patent law. In analyzing in-
 fringement of a utility patent (which is the type of patent
 we usually consider), the task generally consists of simply
 comparing the properly construed patent claim to the ac-
 cused product or method. See, e.g., Philip Morris Prods.
 S.A. v. ITC, 63 F.4th 1328, 1348 (Fed. Cir. 2023).
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 the claimed design from the prior art. Id. at 670–72,
 675–76 (discussing Litton Sys., Inc. v. Whirlpool Corp.,
 728 F.2d 1423 (Fed. Cir. 1984)); see Winner Int’l Corp. v.
 Wolo Mfg. Corp., 905 F.2d 375, 376 (Fed. Cir. 1990) (de-
 scribing this test’s purpose as focusing on aspects of a de-
 sign that render it different from the prior art).
     In Egyptian Goddess, we eliminated the point-of-nov-
 elty test as a separate test and held that the ordinary-ob-
 server test is the sole test for design-patent infringement.
 543 F.3d at 678. In doing so, however, we retained a role
 for prior art in cases where “the claimed and accused de-
 signs are not plainly dissimilar.” Id.; accord Ethicon Endo-
 Surgery, Inc. v. Covidien, Inc., 796 F.3d 1312, 1337
 (Fed. Cir. 2015). Specifically, we explained that in such
 cases the ordinary-observer test should be applied with ref-
 erence to prior-art designs, because those designs can in-
 form the perspective of the hypothetical ordinary observer:
     Particularly in close cases, it can be difficult to an-
     swer the question whether one thing is like another
     without being given a frame of reference. The con-
     text in which the claimed and accused designs are
     compared, i.e., the background prior art, provides
     such a frame of reference and is therefore often use-
     ful in the process of comparison. Where the frame
     of reference consists of numerous similar prior art
     designs, those designs can highlight the distinc-
     tions between the claimed design and the accused
     design as viewed by the ordinary observer.
 Egyptian Goddess, 543 F.3d at 676–77; see Int’l Seaway
 Trading Corp. v. Walgreens Corp., 589 F.3d 1233, 1239
 (Fed. Cir. 2009) (noting that Egyptian Goddess “refined the
 ordinary observer test” by incorporating the context of the
 prior art).
    Comparison prior art can help highlight distinctions
 between the claimed and accused designs because
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      [w]hen the differences between [those] design[s]
      are viewed in light of the prior art, the attention of
      the hypothetical ordinary observer will be drawn to
      those aspects of the claimed design that differ from
      the prior art. And when the claimed design is close
      to the prior art designs, small differences between
      the accused design and the claimed design are
      likely to be important to the eye of the hypothetical
      ordinary observer.
 Egyptian Goddess, 543 F.3d at 676. But such art can also
 cut the other way—i.e., it can highlight similarities be-
 tween the claimed and accused designs. As we explained:
      If the accused design has copied a particular fea-
      ture of the claimed design that departs conspicu-
      ously from the prior art, the accused design is
      naturally more likely to be regarded as deceptively
      similar to the claimed design, and thus infringing.
 Id. at 677.
                                2
     As Columbia notes, the proper scope of comparison
 prior art that may be used in an infringement analysis is
 an issue of first impression for this court.
     Columbia correctly states that a design-patent claim’s
 scope is limited to the article of manufacture identified in
 the claim (which here is heat reflective material), and it
 argues that the scope of comparison prior art should be
 likewise limited. Appellant’s Br. 42, 49 (citing In re Sur-
 gisil, L.L.P., 14 F.4th 1380, 1382 (Fed. Cir. 2021)). Seirus,
 though quick to say “that is not the law,” Cross-Appellant’s
 Br. 46, does not meaningfully dispute that this is an open
 question of law. And, outside of a passing remark that com-
 parison prior art must be “close,” id., Seirus does not de-
 velop a relevant argument as to what the scope should be.
 In any event, we agree with Columbia.
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     We have held that, for a prior-art design to anticipate,
 it must be applied to the article of manufacture identified
 in the claim. Surgisil, 14 F.4th at 1382 (claim scope limited
 to a lip implant; designs applied to other articles—there,
 an art tool—could not anticipate). We have also held that,
 for an accused design to infringe, it must be applied to the
 article of manufacture identified in the claim. See Curver
 Luxembourg, SARL v. Home Expressions Inc., 938 F.3d
 1334, 1336, 1340, 1343 (Fed. Cir. 2019) (claim scope limited
 to a chair; design applied to a basket could not infringe);
 see also Int’l Seaway, 589 F.3d at 1240 (holding that the
 same test applies as between design-patent infringement
 and anticipation). We conclude that this requirement also
 applies to comparison prior art used in an infringement
 analysis. That is, to qualify as comparison prior art, the
 prior-art design must be applied to the article of manufac-
 ture identified in the claim.
     We apply this requirement to comparison prior art for
 a few reasons. First, doing so best accords with comparison
 prior art’s purpose. In an infringement analysis, that pur-
 pose is to help inform an ordinary observer’s comparison
 between the claimed and accused designs—designs that,
 necessarily, must be applied to the same article of manu-
 facture. Naturally, prior-art designs will help in that com-
 parison only to the extent that they too are applied to that
 article of manufacture.
     Second, although the proper scope of comparison prior-
 art designs has never been squarely at issue in our cases,
 requiring that such designs be applied to the article of man-
 ufacture identified in the claim conforms with many cases
 in which courts considered such designs—including the
 cases most instructive on the role of comparison prior art.
 For example, we have regarded the Supreme Court’s Whit-
 man Saddle case as foundational for using comparison
 prior art in an infringement analysis. See Egyptian God-
 dess, 543 F.3d at 672–74, 676 (recounting the history of this
 issue, beginning with Smith v. Whitman Saddle Co.,
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 148 U.S. 674 (1893)). There, the patent covered the design
 of a saddle, and the comparison prior art consisted of sad-
 dles. See 148 U.S. at 675–76, 680–82. Likewise, in Egyp-
 tian Goddess, the patent covered the design of a nail buffer,
 and the comparison prior art consisted of nail buffers.
 543 F.3d at 668, 680–82. Similar examples abound. See,
 e.g., ABC Corp. I v. P’ship & Unincorporated Ass’ns Identi-
 fied on Schedule “A”, 52 F.4th 934, 937–38, 943 (Fed. Cir.
 2022) (hoverboards vs. hoverboard); Wallace v. Ideavillage
 Prods. Corp., 640 F. App’x 970, 971, 975–76 (Fed. Cir. 2016)
 (nonprecedential) (body-washing brush vs. body-washing
 brush); Arminak & Assocs., Inc. v. Saint-Gobain Calmar,
 Inc., 501 F.3d 1314, 1318, 1324–25 (Fed. Cir. 2007)
 (sprayer shroud vs. sprayer shrouds); Unidynamics Corp.
 v. Automatic Prods. Int’l, Ltd., 157 F.3d 1311, 1313, 1324
 (Fed. Cir. 1998) (vending machine for food vs. vending ma-
 chines for food). 8

      8  Although neither party’s briefing raised it as an is-
 sue, we recognize that, in Lanard Toys Ltd. v. Dolgencorp
 LLC, 958 F.3d 1337 (Fed. Cir. 2020), we “[saw] no error” in
 the district court’s rejection of the patentee’s “attempt to
 distinguish its patent [covering a pencil-shaped chalk
 holder] from the prior art [e.g., pencils] by importing . . .
 ‘the chalk holder function of its design’ into the construc-
 tion of the claim.” Id. at 1342–43 (quoting Lanard Toys
 Ltd. v. Toys “R” Us-Del., Inc., No. 3:15-cv-849, 2019 WL
 1304290, at *13 (M.D. Fla. Mar. 21, 2019)). Critically, how-
 ever, the patentee there had not argued that pencil designs
 should not be considered as comparison prior art for the
 design of a pencil-shaped chalk holder—a point the district
 court repeatedly emphasized. Lanard, 2019 WL 1304290,
 at *12 (“Although Lanard emphasizes throughout its brief-
 ing that the [patent] pertains to a chalk holder specifically,
 Lanard does not contend that pencils and pencil-shaped
 containers are not appropriately considered as prior art.”);
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      Third, using the same scope for anticipatory prior art
 and comparison prior art makes good practical sense. This
 standard is already in the system. Surgisil, 14 F.4th
 at 1382. It is also easy to articulate and provides clear
 boundaries. See Curver, 938 F.3d at 1341 (“[T]ying the de-
 sign pattern to a particular article provides more accurate
 and predictable notice about what is and is not protected
 by the design patent.”). Further, close questions may arise
 as to the relationship between a given article of manufac-
 ture and what the claim identifies. Such questions could
 arise in the context of determining whether a prior-art de-
 sign could anticipate or whether an accused design in-
 fringes. But such questions could just as easily arise in the
 context of establishing the comparison prior art itself—i.e.,
 in setting the background for an infringement analysis.
 Using the same standard in each of these contexts allows
 litigants, courts, and the U.S. Patent and Trademark Office
 to benefit from guidance provided in any one of them.
     In sum, we conclude for the foregoing reasons that, to
 qualify as comparison prior art, the prior-art design must
 be applied to the article of manufacture identified in the
 claim.

 id. at *13 n.15 (“Lanard does not dispute that the [c]ourt
 can properly consider such objects in its analysis of the
 prior art.”). Moreover, in the patentee’s appeal to this
 court, the only developed argument in its opening brief con-
 cerning the district court’s treatment of the prior art was
 that the district court had improperly revived the point-of-
 novelty test—an argument we separately rejected.
 Lanard, 958 F.3d at 1344; see also Opening Br. of Pl.-Ap-
 pellant Lanard Toys Ltd. at 24–25, 43–46, Lanard Toys
 Ltd. v. Dolgencorp LLC, No. 19-1781 (Fed. Cir. July 17,
 2019), ECF No. 20. We therefore do not regard Lanard as
 controlling on the proper scope of comparison prior art.
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                               3
      Returning now to the case at hand, Columbia argues
 that the district court erred by failing to instruct the jury
 as to the scope of the D’093 patent claim (design for a heat
 reflective material) and, relatedly, the proper scope of com-
 parison prior art. We agree. That error might be charac-
 terized as a failure to “fairly and adequately cover the
 issues presented,” see Peralta, 744 F.3d at 1082, or the giv-
 ing of “[i]ncomplete instructions,” see Gantt, 717 F.3d
 at 706. The problem was that, aside from the date and pub-
 lication requirements for comparison prior art, the jury
 lacked the correct standard for determining whether an ad-
 mitted reference qualified as such art. Whether a particu-
 lar reference meets that standard for comparison prior
 art—i.e., whether it discloses a design applied to the article
 of manufacture identified in the claim—is a question of fact
 reserved for the fact finder (at least, where there could be
 reasonable disagreement on that fact question such that it
 has not been reduced to a question of law). See, e.g.,
 ADASA, 55 F.4th at 910 (noting in the utility-patent con-
 text that the “question of what a reference teaches and
 whether it describes every element of a claim is a question
 for the finder of fact” (cleaned up)). But the standard itself
 is legal. And the failure to provide it was error—albeit
 quite an understandable one, given that we have only now
 articulated the standard.
     We are also persuaded by Columbia’s showing on this
 record that this error was prejudicial, and we are unper-
 suaded by Seirus’s attempt to show otherwise. Compare
 Appellant’s Br. 60–62, and Appellant’s Reply Br. 25, with
 Cross-Appellant’s Br. 63–66. This prejudicial error war-
 rants vacating the non-infringement judgment and re-
 manding for further proceedings. See, e.g., Blumenthal
 Distrib., Inc. v. Herman Miller, Inc., 963 F.3d 859, 869
 (9th Cir. 2020).
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     Columbia also argues that the district court abused its
 discretion in prohibiting Columbia from trying to distin-
 guish Boorn, Respess, or Blauer as not disclosing designs
 applied to heat reflective material. More generally, Colum-
 bia argues that heat reflective material is a genuinely dis-
 tinct article of manufacture and does not mean just any
 material. Seirus, however, maintains that permitting dis-
 tinctions among materials (as articles of manufacture)
 based on whether they are heat reflective would improperly
 read a functional limitation into Columbia’s design patent.
 E.g., Cross-Appellant’s Br. 38, 43–46. Without opining on
 what might qualify as a heat reflective material—a matter
 not currently before us—we may safely clear up Seirus’s
 general misconception about the role of function in design
 patents.
     It is true that valid design patents cannot be directed
 to designs that are primarily functional, as opposed to or-
 namental. See, e.g., Ethicon, 796 F.3d at 1328. But it is
 also true that “design patents are granted only for a design
 applied to an article of manufacture.” Curver, 938 F.3d
 at 1340 (emphasis added); accord Surgisil, 14 F.4th
 at 1382; see also 35 U.S.C. § 171 (“Whoever invents any
 new, original and ornamental design for an article of man-
 ufacture may obtain a patent therefor . . . .”). And articles
 of manufacture have functions. Ethicon, 796 F.3d at 1328.
 An article’s function “must not be confused with ‘function-
 ality’ of the design of the article.” Hupp v. Siroflex of Am.,
 122 F.3d 1456, 1460 (Fed. Cir. 1997) (emphasis added).
 Concern with the latter is what has featured prominently
 in our case law. The idea is to preclude design-patent pro-
 tection for something that, though purported to be an “or-
 namental” design, is really dictated by function. See
 Ethicon, 796 F.3d at 1328–30.
     Here, the issue we are confronting is not whether the
 D’093 patent’s design (e.g., a wavy pattern) is dictated by
 function. Rather, the issue is whether the claimed article
 to which that design is applied is the same as another
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 article. A natural, relevant consideration for distinguish-
 ing one article from another involves looking to the articles’
 respective functions. That is one way we could tell in Sur-
 gisil that an art tool was not a lip implant: one was “used
 for smoothing and blending large areas of pastel or char-
 coal”; the other was for implanting in a lip. See 14 F.4th
 at 1381–82 (cleaned up). 9 Even if the two designs in Sur-
 gisil might have looked similar in some respects, the art-
 tool design could not anticipate the lip-implant design be-
 cause those designs were applied to different articles. And
 we knew they were different articles at least in part be-
 cause of their different functions. But, aside from clarify-
 ing that referencing functionality to distinguish articles of
 manufacture is not categorically impermissible, we need
 not further address Columbia’s argument that the district
 court abused its discretion in prohibiting Columbia from
 trying to make such distinctions, as we have already re-
 manded for further proceedings based on the comparison-
 prior-art jury-instruction issue.
      Columbia further asks us to direct that none of Boorn,
 Respess, and Blauer be considered as comparison prior art
 at any new trial. This we decline to do in the first instance.
 The main problem with Columbia’s request is that its open-
 ing brief did not adequately preserve a challenge to the dis-
 trict court’s admission of these references. Instead, its

      9  This is not to say that simply including some func-
 tion with a claimed article’s description (e.g., via naming or
 argument) will necessarily exclude articles from a design-
 patent claim’s scope that would otherwise fall within it.
 For example, we suspect that, if a design patent were some-
 how granted for a design applied to a “flower pot for plant-
 ing daisies,” designs applied to prior-art flower pots not so
 designated could still anticipate. Including that additional
 function (“for planting daisies”) would not necessarily ren-
 der the article genuinely distinct from other flower pots.
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 brief focused on the district court’s jury instructions and
 prohibition of Columbia’s attempt to distinguish the admit-
 ted references. See, e.g., Appellant’s Br. 2–4 (Statement of
 the Issues); id. at 41–44 (Summary of Argument); see also
 Oral Arg. at 10:16–11:00, 15:37–16:08, 18:03–19:28 (dis-
 cussing the preservation issue). 10 That preservation short-
 coming, along with the fact that the district court has not
 yet had a chance to engage with the standard we have ar-
 ticulated, counsels against granting Columbia’s request. 11
      On remand, the district court will likely be confronted
 with questions implicating what qualifies as heat reflective
 material. Such questions could be difficult to answer with-
 out knowing what heat reflective material is. The district
 court may therefore wish to consider construing that term.
 The parties have at various points offered their view of
 what it means. Columbia has indicated it means “a mate-
 rial designed to reflect heat,” see J.A. 6696 (Columbia’s
 Opening Markman Brief), or “metallic foil on a base mate-
 rial to reflect heat,” Appellant’s Br. 63 (citing J.A. 617–18).
 Seirus, on the other hand, has indicated that heat reflective
 material means any material—on the theory that, as a
 matter of physics, all materials reflect heat to some extent.
 See Cross-Appellant’s Br. 49 (citing J.A. 363). Without
 evaluating the merit of Seirus’s position, we feel compelled
 to note that the accused design here is not applied to just

     10  No. 21-2299, https://oralarguments.cafc.uscourts.
 gov/default.aspx?fl=21-2299_01122023.mp3.
     11  Given the circumstances, however—including Co-
 lumbia’s other challenges concerning comparison prior art
 and the proper scope of such art being an issue of first im-
 pression—we do not think any forfeiture-based “law of the
 case” principles regarding Columbia’s inadequate preser-
 vation of an appellate challenge to the district court’s ad-
 mission of these references should bar any effort by
 Columbia to secure their exclusion at any new trial.
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 any material. It is instead applied to material (called Heat-
 Wave, of all things) that Seirus touts for its heat reflective
 qualities. See, e.g., J.A. 3834 (Seirus marketing materials
 describing HeatWave as “reflect[ing] radiated heat back for
 more warmth”). This might suggest that, at least in the
 minds of some, heat reflective material connotes something
 genuinely distinct from just any material. But again, we
 leave it to the district court on remand to determine
 whether and to what extent the term needs construing.
                               B
      We turn now to Columbia’s jury-instruction challenges
 related to Seirus’s logo. Columbia challenges the district
 court’s jury instructions as erroneous for not specifying
 (1) that consumer confusion as to source is irrelevant to de-
 sign-patent infringement, or (2) that a jury need not find a
 likelihood of consumer confusion to find such infringement.
 Because Columbia’s challenges implicate distinctions be-
 tween trademark (including trade-dress) law on the one
 hand and design-patent law on the other, we briefly discuss
 the relevant legal principles applicable to each before con-
 sidering those challenges.
                               1
     Trademark and design-patent infringement differ as to
 the relevance of consumer confusion regarding a product’s
 source. Trademark infringement requires that consumers
 will likely be confused as to a product’s source. 12 See, e.g.,
 Moseley v. V Secret Catalogue, Inc., 537 U.S. 418, 428

      12 Although trademark infringement contemplates
 additional types of confusion, see, e.g., J. Thomas McCar-
 thy, 4 McCarthy on Trademarks and Unfair Competition
 §§ 23:5, 23:8, 24:6 (5th ed. 2023), for simplicity’s sake—and
 because of the nature of Columbia’s jury-instruction chal-
 lenges—we refer specifically to confusion as to a product’s
 source.
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 (2003) (noting that the Lanham Act “broadly prohibits uses
 of trademarks, trade names, and trade dress that are likely
 to cause confusion about the source of a product”); see also
 4 McCarthy § 23:1; 1 McCarthy § 8:1. For design-patent
 infringement, however, “[l]ikelihood of confusion as to the
 source of the goods is not a necessary or appropriate fac-
 tor.” Unette Corp. v. Unit Pack Co., 785 F.2d 1026, 1029
 (Fed. Cir. 1986); see also Braun Inc. v. Dynamics Corp. of
 Am., 975 F.2d 815, 828 (Fed. Cir. 1992) (noting that, while
 “purchasers’ likelihood of confusion as to the source of a
 good is a necessary factor for determining trademark and
 trade dress infringement,” “a different quantum of proof
 applies to design patent infringement, which does not con-
 cern itself with the broad issue of consumer behavior in the
 marketplace”).
      Given this difference, applying a logo or other clear
 source identifier in conjunction with a product can create
 different effects as between trademark and design-patent
 infringement. For trademark infringement, a distinctive
 logo’s application can, under some circumstances, be signif-
 icant evidence that there will be no consumer confusion as
 to a product’s source, and therefore no infringement. See,
 e.g., Groeneveld Transp. Efficiency, Inc. v. Lubecore Int’l,
 Inc., 730 F.3d 494, 515 (6th Cir. 2013) (“[The accused in-
 fringer] has in fact scrupulously avoided such confusion by
 choosing a starkly different logo that it prominently dis-
 plays on its [products] and on all its sales and marketing
 literature.”); Int’l Ass’n of Machinists & Aerospace Workers,
 AFL-CIO v. Winship Green Nursing Ctr., 103 F.3d 196, 204
 (1st Cir. 1996) (“[W]e have recognized that in certain cir-
 cumstances otherwise similar marks are not likely to be
 confused if they are used in conjunction with clearly dis-
 played names, logos[,] or other source-identifying designa-
 tions of the manufacturer.” (collecting cases)); see also
 Converse, Inc. v. ITC, 909 F.3d 1110, 1124 (Fed. Cir. 2018)
 (noting, in a trade-dress case, that “we have not held that
 [brand-name] labeling is always legally sufficient to avoid
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 30             COLUMBIA SPORTSWEAR NORTH AMERICA, INC. v.
                       SEIRUS INNOVATIVE ACCESSORIES, INC.

 likelihood of confusion but rather that those labels may be
 highly probative evidence”); 4 McCarthy § 23:53.
     Logos are analyzed somewhat differently in the design-
 patent context. Again, because design-patent infringement
 does not consider consumer confusion as to source, such in-
 fringement “is not avoided ‘by labelling.’” Columbia I,
 942 F.3d at 1131 (quoting L.A. Gear, 988 F.2d at 1126); see
 also id. (“A would-be infringer should not escape liability
 for design patent infringement if a design is copied but la-
 beled with its name.”). But logos are hardly irrelevant, ei-
 ther. As we explained in Columbia I, our precedent “does
 not prohibit the fact finder from considering an ornamental
 logo, its placement, and its appearance as one among other
 potential differences between” a claimed and accused de-
 sign. See id. (emphasis in original). Indeed, it would be
 improper “to ignore elements of the accused design en-
 tirely, simply because those elements included the name of
 the [accused infringer].” Id.
     The takeaway is: just because consumers might not be
 confused about an accused product’s source, that alone
 would not preclude an ordinary observer from deeming the
 claimed and accused designs similar enough to constitute
 design-patent infringement. See Braun, 975 F.2d at 828
 (discussing differences between trademark and design-pa-
 tent infringement and noting that what matters for the lat-
 ter is “that an ordinary observer would be deceived by
 reason of an accused [product]’s ornamental design” (em-
 phasis added)). At the same time, however, just because a
 logo’s potential to eliminate confusion as to source is irrel-
 evant to design-patent infringement, its potential to render
 an accused design dissimilar to the patented one—maybe
 even enough to establish non-infringement as a matter of
 law—should not be discounted.
                               2
    With these legal principles in mind, we consider Co-
 lumbia’s logo-related jury-instruction challenges.
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      Again, the district court’s jury instruction on design-
 patent infringement did two basic things. First, it recited
 the ordinary-observer test for infringement—the very test
 we endorsed in Columbia I and have endorsed numerous
 times in the past. J.A. 1520; see Columbia I, 942 F.3d
 at 1129; see also, e.g., Egyptian Goddess, 543 F.3d at 678
 (“[I]n accordance with Gorham and subsequent decisions,
 we hold that the ‘ordinary observer’ test should be the sole
 test for determining whether a design patent has been in-
 fringed.”). Second, it added that the jury did “not need,
 however, to find that any purchasers were actually de-
 ceived or confused by the appearance of the accused prod-
 ucts.” J.A. 1520.
     Columbia insists that the district court erred by not go-
 ing further—by not adding that consumer confusion as to
 source is irrelevant for design-patent infringement, or that
 likelihood of confusion (in addition to actual confusion)
 need not be found. We disagree. The district court gave
 the ordinary-observer test for design-patent infringement
 materially identically to how the Supreme Court and this
 court have stated it, and it added that actual confusion was
 not necessary to find design-patent infringement. These
 could hardly be called incorrect statements of law. And we
 are not convinced that the district court’s decision not to
 include Columbia’s requested additions or clarifications
 was an abuse of discretion or resulted in instructions that
 were misleading or incomplete. 13

     13  Indeed, although Columbia challenges the jury in-
 structions, its real complaint seems to lie with the follow-
 ing statement Seirus made during closing:
     Hard to imagine with all those logos that an ordi-
     nary observer, the consumer, would be
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 32              COLUMBIA SPORTSWEAR NORTH AMERICA, INC. v.
                        SEIRUS INNOVATIVE ACCESSORIES, INC.

     That said, we are not insensitive to Columbia’s over-
 arching concern. At a surface level, the ordinary-observer
 test could be read as evoking concepts of consumer confu-
 sion as to source, given that it asks whether the resem-
 blance between two designs “is such as to deceive [an
 ordinary] observer, inducing him to purchase one suppos-
 ing it to be the other,” Gorham, 81 U.S. at 528. In design-
 patent-infringement cases involving logos, we appreciate
 the potential for a jury to be led astray and mistakenly con-
 flate the significance of a logo’s source-identifying function
 with whatever impact it might have on a comparison of the
 designs. But district courts are in the best position to de-
 cide whether and when to provide clarification in the
 course of conducting a trial. And here we see no legal error
 or abuse of discretion in the district court’s jury instruc-
 tions, which are the only subject of Columbia’s challenge on
 this issue.
                              III
    We turn now to Seirus’s conditional cross-appeal re-
 garding damages.
    Seirus argues that, for purposes of calculating damages
 under 35 U.S.C. § 289, 14 the relevant “article of

      deceived . . . . I don’t see how that’s possible be-
      cause Seirus is telling the world this is ours. This
      is ours.
 Appellant’s Br. 77 (emphasis and alterations supplied by
 Columbia) (quoting J.A. 1225–26). But, outside of using
 these statements to animate its challenges to the jury in-
 structions, Columbia has not suggested that these state-
 ments themselves provide a basis for appellate relief.
     14  Section 289 provides (in relevant part):

         Whoever during the term of a patent for a design,
         without license of the owner, (1) applies the
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 manufacture” is the HeatWave material—not the entire
 end product to which it is applied (e.g., gloves with portions
 not made of HeatWave material).             Cross-Appellant’s
 Br. 66–67 (encouraging us to “streamline further proceed-
 ings” by so holding). Seirus also argues that the district
 court erred by instructing the jury (at the damages trial)
 that Seirus bore the burden of proving that the article of
 manufacture for § 289 damages purposes is less than the
 entire end product. According to Seirus, Columbia—as the
 patentee—bore the burden of proving what that article is.
 The parties further disagree as to whether any damages
 retrial on profit-disgorgement issues should be tried to a
 jury or the bench.
     As we indicated in Columbia I, these are important is-
 sues. See 942 F.3d at 1132. But we did not reach them
 there because our disposition left the case with no infringe-
 ment determination. See id. Because our disposition here
 likewise leaves the case without an infringement determi-
 nation, we do not reach these issues.
                         CONCLUSION
     We have considered the parties’ remaining arguments
 and find them unpersuasive. For the foregoing reasons, we
 vacate the non-infringement judgment and remand for fur-
 ther proceedings.

         patented design, or any colorable imitation thereof,
         to any article of manufacture for the purpose of
         sale, or (2) sells or exposes for sale any article of
         manufacture to which such design or colorable im-
         itation has been applied shall be liable to the owner
         to the extent of his total profit, but not less than
         $250, recoverable in any United States district
         court having jurisdiction of the parties.

     35 U.S.C. § 289.
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 34              COLUMBIA SPORTSWEAR NORTH AMERICA, INC. v.
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                VACATED AND REMANDED
                           COSTS
 Costs to Columbia.