Case: 19-1622 Document: 59 Page: 1 Filed: 06/25/2020
`
`
`
`
`United States Court of Appeals
`for the Federal Circuit
`______________________
`
`SHOES BY FIREBUG LLC,
`Appellant
`
`v.
`
`STRIDE RITE CHILDREN'S GROUP, LLC,
`Appellee
`______________________
`
`2019-1622, 2019-1623
`______________________
`
`Appeals from the United States Patent and Trademark
`Office, Patent Trial and Appeal Board in Nos. IPR2017-
`01809, IPR2017-01810.
`______________________
`
`Decided: June 25, 2020
`______________________
`
`WILLIAM ALCIATI, Gardella Grace PA, Washington, DC,
`for appellant.
`
` GAETAN GERVILLE-REACHE, Warner Norcross & Judd
`LLP, Grand Rapids, MI, for appellee. Also represented by
`ROBERT MICHAEL AZZI.
` ______________________
`
`Before LOURIE, MOORE, and O’MALLEY, Circuit Judges.
`LOURIE, Circuit Judge.
`
`

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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`Shoes by Firebug LLC (“Firebug”) appeals from two fi-
`nal written decisions of the United States Patent and
`Trademark Office Patent Trial and Appeal Board (“the
`Board”) holding claims 1–10 of U.S. Patent 8,992,038 (“’038
`patent”) and claims 1–10 of U.S. Patent 9,301,574 (“’574
`patent”) unpatentable as obvious. See Stride Rite Chil-
`dren’s Grp., LLC v. Shoes by Firebug LLC, No. IPR2017-
`01809, 2019 WL 236242 (P.T.A.B. Jan. 16, 2019) (“-1809
`Decision”); Stride Rite Children’s Grp., LLC v. Shoes By
`Firebug LLC, No. IPR2017-01810, 2019 WL 237069
`(P.T.A.B. Jan. 16, 2019) (“-1810 Decision”). Because the
`Board did not err in its conclusion that the claims would
`have been obvious over the prior art, we affirm.
`BACKGROUND
`Firebug owns the ’038 and ’574 patents (collectively the
`“Firebug patents”), which are generally directed to illumi-
`nation systems for footwear. ’038 patent col. 1 ll. 10–12.1
`According to the patents, while light-up shoes are not new
`to the footwear industry, there is a wide variety of struc-
`tural designs for illuminated footwear. In some designs,
`the light sources are external to the footwear, while in oth-
`ers the lights are integrated into the shoes. The Firebug
`patents purport to disclose an improved structure for inter-
`nally illuminated footwear. The patents describe footwear
`comprising a sole and an upper portion having three lay-
`ers—a liner, which is the innermost layer, an interfacing
`layer, and a light-diffusing layer. Id. col. 2 l. 45–col. 3 l. 8.
`The light sources are connected to the interfacing layer be-
`tween the interfacing layer and the light diffusing layer.
`Id. col. 2 l. 65–col. 3 l. 1. The interfacing layer is a reflec-
`tive layer that maximizes the amount of light that exits
`through the light-diffusing layer and is ultimately visible
`
`1 Because the ’038 and ’574 patents share a substan-
`tially identical written description, all citations are to the
`’038 patent unless specified otherwise.
`
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`to an observer. Id. col. 3 ll. 3–5. Claim 1 of the ’038 patent
`is illustrative:
`1. An internally illuminated textile footwear com-
`prises:
`a footwear;
`the footwear comprises a sole and an upper;
`an illumination system;
`the illumination system comprises a power source
`and a plurality of illumination sources;
`a liner;
`a structure;
`the structure comprises an interfacing layer and a
`batting;
`the structure being adjacently connected to the up-
`per;
`the structure being positioned between the liner
`and the upper;
`the interfacing layer being positioned adjacent to
`the liner;
`the batting being adjacently connected to the inter-
`facing layer opposite the liner;
`the interfacing layer being reflective;
`the batting being light diffusing;
`the plurality of illumination sources being adja-
`cently connected to the interfacing layer;
`the plurality of illumination sources being posi-
`tioned between the interfacing layer and the bat-
`ting;
`
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`the upper being perimetrically connected to the
`sole;
`the liner being positioned interior to the upper;
`the upper being light diffusing;
`the illumination system being housed within the
`footwear;
`the plurality of illumination sources emitting light,
`wherein the light first entering the batting and be-
`ing diffused by the batting, the light diffused by the
`batting exits the batting, enters the upper, diffused
`again by the upper and then exits the upper, the
`twice diffused light creating a visual impression of
`internal radiant illumination across an outer sur-
`face area of the upper.
`’038 patent col. 7 ll. 26–57 (emphasis added).
`Claim 1 of the ’574 patent recites similar subject mat-
`ter, with slight differences relevant to this appeal.
`1. An internally illuminated textile footwear com-
`prises:
`a sole and an upper;
`an illumination system;
`the illumination system comprises a power source
`and a plurality of illumination sources;
`a liner;
`an interfacing layer;
`the interfacing layer being adjacently connected to
`the upper;
`the interfacing layer being positioned between the
`liner and the upper;
`
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`the plurality of illumination sources being adja-
`cently connected to the interfacing layer;
`the plurality of illumination sources being posi-
`tioned between the interfacing layer and the upper;
`the upper being perimetrically connected to the
`sole;
`the liner being positioned interior to the upper;
`the upper being a light diffusing section;
`the illumination system being housed within the
`footwear; and
`the plurality of illumination sources emitting light,
`wherein the light enters the light diffusing section,
`then exits the upper as diffused light, creating a
`visual impression of internal radiant illumination
`across an outer surface of the upper.
`’574 patent col. 9 l. 47–col. 10 l. 5 (emphasis added).
`Stride Rite Children’s Group, LLC (“Stride Rite”) is a
`competitor to Firebug in the children’s footwear market.
`Firebug asserted the ’038 and ’574 patents against Stride
`Rite in the United States District Court for the Eastern
`District of Texas. See Complaint, Shoes by Firebug LLC v.
`Stride Rite Children’s Grp., LLC, No. 4:16-cv-00899 (E.D.
`Tex. Nov. 22, 2016), ECF No. 1. Stride Rite in response
`filed petitions for inter partes review of claims 1–10 of the
`’038 patent and claims 1–10 of the ’574 patent, alleging
`that the challenged claims would have been obvious over
`U.S. Patent 5,894,686 (“Parker”) in view of U.S. Patent
`App. Pub. 2011/0271558 (“Rosko”) and other references.
`Parker teaches a light distribution system for use on
`the upper portion of a shoe and discloses a layer of woven
`or non-woven optical fibers disposed on a “back reflector,”
`which reflects light from the optical fibers back through the
`outer layer of the shoe. Parker, col. 4 ll. 18–34. Rosko
`
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`discloses a multi-layered lighting panel for footwear that
`uses an array of light-emitting diodes disposed in a “light
`diffuser” for illumination. Rosko ¶ 23. Stride Rite con-
`tended that the challenged claims would have been obvious
`because a skilled artisan would have substituted Parker’s
`fragile optical fiber layer with Rosko’s LED-based light dif-
`fuser to reduce cost and improve the structural integrity of
`the footwear.
`The Board instituted trial on both petitions and issued
`a final written decision in each proceeding concluding that
`the challenged claims are unpatentable as obvious. In both
`decisions, the Board determined that the preamble of claim
`1 of each of the Firebug patents, which is the only inde-
`pendent claim at issue in each IPR, does not limit the chal-
`lenged claims. -1809 Decision, 2019 WL 236242, at *6; -
`1810 Decision, 2019 WL 237069, at *8. The Board con-
`cluded that the references otherwise render the challenged
`claims obvious and the disclosure of the references is not
`outweighed by Firebug’s evidence of secondary considera-
`tions of nonobviousness. -1809 Decision at *23–24; -1810
`Decision at *24.
`Firebug timely appealed the Board’s decisions. We
`have jurisdiction under 28 U.S.C. § 1295(a)(4)(A).
`DISCUSSION
`Firebug presents two principal arguments on appeal.
`First, it argues that the Board erred in determining that
`the preambles of claim 1 of both the ’038 and ’574 patents
`do not limit the claims. Second, it argues that the Board
`erred in concluding that the challenged claims would have
`been obvious in light of the prior art and Firebug’s evidence
`of secondary considerations of nonobviousness. We ad-
`dress Firebug’s arguments in turn.
`I. Claim Construction
`“Claim construction is a question of law that may in-
`volve underlying factual questions.” Amgen Inc. v. Amneal
`
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`Pharm. LLC, 945 F.3d 1368, 1375 (Fed. Cir. 2020) (citing
`Teva Pharm. USA, Inc. v. Sandoz, Inc., 574 U.S. 318, 332
`(2015)). Where, as here, the lower tribunal’s construction
`is based solely on evidence intrinsic to the patent, we re-
`view the construction de novo. Shire Dev., LLC v. Watson
`Pharm., Inc., 787 F.3d 1359, 1364 (Fed. Cir. 2015) (citing
`Teva, 574 U.S. at 330–33).
`Firebug argues that the Board erred in determining
`that the preamble of claim 1 of each of the Firebug patents,
`which recites “[a]n internally illuminated textile footwear
`comprises,” does not limit the claims. Specifically, Firebug
`argues that the preamble limits the scope of the claims to
`“textile footwear.” According to Firebug, when the pream-
`ble’s requirement of textile footwear is read together with
`the claims’ limitation that the upper is light diffusing, the
`claims necessarily require that the light diffusing portion
`of the upper—that is, the portion of the outermost layer of
`the footwear that is illuminated—be textile. Firebug ar-
`gues that neither Parker nor Rosko disclose internally illu-
`minated footwear having a textile light diffusing layer and
`therefore the references do not render the claims obvious.
`Stride Rite responds that the preambles do not limit
`any of the challenged claims because the bodies of the
`claims recite structurally complete articles, and the pream-
`ble merely states an intended use of the claimed structure.
`However, according to Stride Rite, even if the preambles do
`limit the claims to require textile footwear, the Board’s
`claim construction error was harmless because the Board
`alternatively found that the prior art discloses footwear
`with a textile upper, and that finding is supported by sub-
`stantial evidence.
`Whether a claim preamble is considered to be a limit-
`ing part of the claim matters, inter alia, because, if it is not,
`the scope of the claim is broader, but the claim is vulnera-
`ble to more potentially-invalidating prior art. Here, we
`agree with Firebug that the preamble of claim 1 of the ’574
`
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`patent is limiting but conclude that the preamble of claim
`1 of the ’038 patent is not. However, we agree with Stride
`Rite that even though the preamble is limiting with respect
`to the challenged claims of the ’574 patent, the Board’s al-
`ternative determination that the references nevertheless
`disclose the limitation is supported by substantial evi-
`dence. Thus, our conclusion does not upset the Board’s
`overall conclusion of obviousness.
`“Whether to treat a preamble as a limitation is a deter-
`mination ‘resolved only on review of the entire[] . . . patent
`to gain an understanding of what the inventors actually in-
`vented and intended to encompass by the claim.’” Catalina
`Mktg. Int’l, Inc. v. Coolsavings.com, Inc., 289 F.3d 801, 808
`(Fed. Cir. 2002) (quoting Corning Glass Works v. Sumitomo
`Elec. U.S.A., Inc., 868 F.2d 1251, 1257 (Fed. Cir. 1989)) (al-
`terations in original). “In general, a preamble limits the
`invention if it recites essential structure or steps, or if it is
`‘necessary to give life, meaning, and vitality’ to the claim.”
`Id. (quoting Pitney Bowes, Inc. v. Hewlett-Packard Co., 182
`F.3d 1298, 1305 (Fed. Cir. 1999)). “Conversely, a preamble
`is not limiting ‘where a patentee defines a structurally com-
`plete invention in the claim body and uses the preamble
`only to state a purpose or intended use for the invention.’”
`Id. (quoting Rowe v. Dror, 112 F.3d 473, 478 (Fed. Cir.
`1997)). “No litmus test defines when a preamble limits
`claim scope,” id. (citing Corning Glass, 868 F.2d at 1257),
`but “dependence on a particular disputed preamble phrase
`for antecedent basis may limit claim scope because it indi-
`cates a reliance on both the preamble and claim body to
`define the claimed invention.” Id. (citing Bell Commc’ns
`Research, Inc. v. Vitalink Commc’ns Corp., 55 F.3d 615, 620
`(Fed. Cir. 1995)).
`We conclude that the body of claim 1 of the ’038 patent
`recites a structurally complete invention, and therefore the
`preamble’s recitation of an “internally illuminated textile
`footwear” is merely an intended purpose that does not limit
`the claims. Notably, the first limitation of the body of
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`claim 1 of the ’038 patent reintroduces “a footwear” which
`“comprises a sole and an upper.” The preamble, then, can-
`not be said to provide essential structure or necessary
`meaning to the claimed invention because the same ele-
`ment—the footwear—is independently recited in the body
`of the claim. The body does not go on to expressly impose
`any further limitation on the footwear requiring use of a
`specific material, nor is a requirement of textile footwear
`implicitly necessary to the invention. Indeed, the written
`description itself discloses numerous materials other than
`textile suitable for footwear manufacture, including
`“leather, synthetics, [and] plastics.” ’038 patent col. 1
`ll. 18–19.
`Firebug argues that the written description treats the
`use of textile footwear as an important aspect of the disclo-
`sure, and therefore the recitation of “textile footwear” in
`the preamble should be treated as limiting. The written
`description explains that “[t]he present invention focuses
`on the adoption and improvement of internally illuminated
`footwear . . . by providing a light diffusing textile upper.”
`’038 patent col. 1 ll. 37–39. In addition to the general dis-
`favor of importing language from the written description
`into the claims, see SuperGuide Corp. v. DirecTV Enters.,
`Inc., 358 F.3d 870, 875 (Fed. Cir. 2004), we disagree with
`Firebug that the use of textile footwear is essential to real-
`izing the stated purpose of the invention. Internal illumi-
`nation is achieved by the multilayer design recited in the
`claims in which the light sources are integrated into the
`footwear between the interior interfacing layer and the ex-
`terior light diffusing layer. Of course, the light diffusion
`layer must be light permeable to allow light to escape the
`footwear, but this suggests that light permeability, not the
`use of a particular material, is the critical characteristic of
`the upper.
`The written description and the body of claim 1 accord
`with this understanding. The patent explains that “[t]ex-
`tile materials . . . are just one possible material type which
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`can be used for the light diffusing section,” ’038 patent
`col. 4 ll. 46–50, and the body of claim 1 requires only that
`“the upper be[] light diffusing” without limiting the scope
`of the claim to a particular material. Id. col. 7 ll. 49. Ac-
`cordingly, because the body of claim 1 of the ’038 patent
`recites a structurally complete article and the use of textile
`material is not otherwise necessary to the claimed inven-
`tion, we conclude that the preamble of claim 1 does not
`limit claims 1–10 of the ’038 patent.
`Unlike claim 1 of the ’038 patent, claim 1 of the ’574
`patent does not reintroduce “footwear” in the body of the
`claim but instead relies on the instance of “footwear” intro-
`duced in the preamble for “antecedent basis.” Claim 1 of
`the ’574 patent recites an illumination system comprising
`“a power source and a plurality of illumination sources.”
`The first and only reference to footwear in the body of claim
`1 appears in a limitation describing the configuration of the
`illumination system (“the illumination system being
`housed within the footwear”) and relies on the footwear re-
`cited in the preamble for an antecedent basis for further
`limitations in the claim. While antecedent basis alone is
`not determinative of whether a preamble is limiting, use of
`preamble terms to define positive limitations in the body of
`claims can evince an inventor’s intent that the preamble
`limit the scope of the claim. That is the case here. Because
`the claim requires that the illumination system be housed
`in the textile footwear recited in the preamble, the pream-
`ble is essential to understanding the structural limitations
`of the illumination system. Accordingly, rather than
`merely reciting an intended purpose of the claimed inven-
`tion, we conclude that the preamble of claim 1 of the ’574
`patent limits the scope of claims 1–10 of the ’574 patent to
`require the use of a textile upper.
`However, although the Board erred in omitting the pre-
`amble from its claim construction of the ’574 patent, we
`conclude that the Board’s alternative fact findings that the
`references disclose the use of textile footwear are supported
`
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`by substantial evidence and that the Board’s error was
`therefore harmless. See In re Watts, 354 F.3d 1362, 1369
`(Fed. Cir. 2004) (“[T]he harmless error rule applies to ap-
`peals from the Board.”) (citing In re McDaniel, 293 F.3d
`1379, 1385–86 (Fed. Cir. 2002); Gechter v. Davidson, 116
`F.3d 1454, 1457 (Fed. Cir. 1997)). The Board noted that
`although it did not construe the preamble as limiting,
`Rosko “suggests using a woven, porous material in a light
`diffusing, internally illuminated part of footwear.” -1810
`Decision, 2019 WL 237069, at *8 n.16. Specifically, Rosko
`suggests constructing its display panel from a woven, po-
`rous material—such as textile—and provides a rationale
`for doing so: according to Rosko, “[s]uch material would fur-
`ther assist in diffusing light because its porosity would
`tend to spread, disperse, and diffuse light.” Rosko ¶ 22. We
`note also that the ’574 patent itself acknowledges that tex-
`tiles have been used in the production of footwear “over
`many decades.” ’574 patent col. 1 ll. 19–22. The disclosure
`of Rosko and statements of the ’574 patent constitute sub-
`stantial evidence supporting the Board’s determination
`that the use of a textile light diffusing section would have
`been obvious. Thus, although we agree with Firebug that
`the preamble of claim 1 of the ’574 patent limits the chal-
`lenged claims to require textile footwear, we conclude that
`the Board’s ultimate conclusion of obviousness is correct
`under the proper claim construction and that the Board’s
`error was therefore harmless.
`II. Obviousness
`Obviousness is a question of law that “lends itself to
`several basic factual inquiries,” Graham v. John Deere Co.,
`383 U.S. 1, 17–18 (1966) (citing Great Atl. & Pac. Tea Co.
`v. Supermarket Equip. Corp., 340 U.S. 147, 155 (1950)), in-
`cluding the scope and content of the prior art, the level of
`ordinary skill in the art, differences between the prior art
`and the claimed invention, and any relevant secondary con-
`siderations. Id. “We review the PTAB’s factual findings
`for substantial evidence and its legal conclusions de novo.”
`
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`Redline Detection, LLC v. Star Envirotech, Inc., 811 F.3d
`435, 449 (Fed. Cir. 2015) (citing Rambus Inc. v. Rea, 731
`F.3d 1248, 1251 (Fed. Cir. 2013)). A finding is supported
`by substantial evidence if a reasonable mind might accept
`the evidence as adequate to support the finding. Consol.
`Edison Co. v. NLRB, 305 U.S. 197, 229 (1938). “If two ‘in-
`consistent conclusions may reasonably be drawn from the
`evidence in record, the PTAB’s decision to favor one conclu-
`sion over the other is the epitome of a decision that must
`be sustained upon review for substantial evidence.’” Elbit
`Sys. of Am., LLC v. Thales Visionix, Inc., 881 F.3d 1354,
`1356 (Fed. Cir. 2018) (quoting In re Cree, Inc., 818 F.3d 694,
`701 (Fed. Cir. 2016) (internal brackets omitted)).
`A. “Interfacing layer”
`Independent of its claim construction argument, Fire-
`bug also challenges the Board’s conclusion that the claims
`otherwise would have been obvious over the references.
`Specifically, Firebug argues that the combination of Parker
`and Rosko fails to disclose the claimed interfacing layer be-
`cause the “back reflector” of Parker is a permanently fixed
`coating of Parker’s optical fibers and would not be retained
`if the optical fibers were replaced by Rosko’s LEDs, as pro-
`posed by Stride Rite.
`Stride Rite counters that the Board’s determination
`that the combination of Parker and Rosko discloses the in-
`terfacing layer is supported by substantial evidence. Stride
`Rite points to the testimony of its expert, Lenny Holden,
`that a skilled artisan would have substituted Rosko’s LEDs
`for the optical fibers of Parker, resulting in the claimed
`structure.
`We agree with Stride Rite that the Board’s conclusion
`is supported by substantial evidence. The challenged
`claims require that the interfacing layer be “adjacently con-
`nected” to the light diffusing layer, with the illumination
`sources positioned between the two layers. ’038 patent
`col. 7 ll. 39–40; ’574 patent col. 9 ll. 55–56. Parker’s back
`
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`reflector is not adjacently connected to a light diffusing
`layer opposite the illumination source because the optical
`fibers form a solid layer separating the back reflector fi‘om
`the outer layer of the footwear. To demonstrate that the
`limitation nonetheless would have been obvious, Stride
`Rite in its petitions proposed replacing the optical fiber
`layer of Parker with the light diffusers of Rosko, which use
`discrete LEDs as a light source. J.A. 2030—32; 2082—84.
`Stride Rite offered the following illustrations depicting a
`cross-sectional view of the disclosed structure of Parker
`
`and Stride Rite’s proposed modifications:
`
`
`
`
`LININGJ!
`
`max mac TOR Is
`
`OUTER SHOE
`COVERING.”
`
`OV'IKAL "EH“. 5
`
`POROUS MATERIAL 35
`
`WINDOW, 36
`
`OUTER SHOE
`COVERING, 34
`
`
`
`
`UNWG. 33
`
`WINDOW. 36
`
`POROUS MATERIAL. BS
`
`DIFFUSERS. S
`
`BACK REFLEC'IOR. ‘5
`
`
`
`According to Stride Rite, the use of discrete LEDs (de-
`noted as “Diffusers, 5” in the above illustration) would cre-
`ate space between the light sources in which the back
`reflector (i.e. the interfacing layer) would be “adjacently
`connected” to the light diffusing layer.
`In support of its
`proposed modification, Stride Rite cited to the declaration
`of Holden, who opined that replacing the optical fibers of
`Parker with Rosko’s LEDs would “increase the durability
`
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`of the shoe in Parker and decrease material costs.” J.A.
`2607 ¶ 87.
`In its response, Firebug argued that Parker’s back re-
`flector is an optical layer associated with the optical fibers
`that would have no function in the absence of the optical
`fibers and that there would be no reason to retain Parker’s
`back reflector because the light diffusers of Rosko already
`include a reflective sheet. J.A. 2926–27.
`After weighing the parties’ positions, the Board deter-
`mined that Stride Rite’s proposed combination of Parker
`and Rosko accounted for the claimed interfacing layer and
`that Stride Rite had articulated sufficient reasons to com-
`bine the known elements in the claimed arrange-
`ment. -1809 Decision, 2019 WL 236242, at *23; -1810
`Decision, 2019 WL 237069, at *24.
`Firebug argues that we must reverse the Board be-
`cause its finding is not supported by substantial evidence.
`We disagree. The Board was presented with two alterna-
`tive theories as to whether a skilled artisan would or would
`not have substituted Rosko’s LEDs for Parker’s optical fi-
`bers as proposed by Stride Rite. Our task is not to deter-
`mine which theory we find more compelling. “[I]t is not for
`us to second-guess the Board’s assessment of the evidence.”
`Velander v. Garner, 348 F.3d 1359, 1378 (Fed. Cir. 2003).
`Rather, the only question before us is whether the conclu-
`sion adopted by the Board is supported by substantial evi-
`dence. Here, we conclude that it is.
`Parker and Rosko both suggest that LEDs would be a
`suitable alternative for optical fibers. Parker discloses
`LEDs as one possible light source for its optical fibers, Par-
`ker, col. 4 ll. 63–64, while Rosko explains that, although its
`light source “is typically a light-emitting diode . . . any
`source of light may be used such as . . . optic fiber.” Rosko
`¶ 23. And as noted by the Board, Holden explained that at
`the time of the invention optical fibers were known to be
`more expensive than LEDs and that the use of LEDs would
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`15
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`result in more durable footwear. As to the back reflector,
`the Board credited Holden’s testimony that a person of skill
`would have retained the back reflector for use with the sub-
`stituted LEDs “to maximize the distribution of light.” J.A.
`2604 ¶ 83. This testimony accords with the disclosure of
`Parker, which explains that the purpose of the back reflec-
`tor is to redirect light back through the light source “such
`that light is emitted from only the front side of the light
`emitting portion.” Parker, col. 4 ll. 30–34. Based on the
`disclosure of the references and Holden’s testimony, we
`conclude that the Board’s determination that a skilled ar-
`tisan would have been motivated to combine Parker and
`Rosko in the manner proposed by Stride Rite, and that the
`combination discloses the claimed limitations of the inter-
`facing layer, is supported by substantial evidence.
`None of Firebug’s arguments on appeal demonstrate
`otherwise. First, Firebug argues that, because Parker’s
`back reflector is a coating of the optical fibers, the reflector
`is coextensive with the light source. Thus, according to
`Firebug, if the optical fibers were replaced with discrete
`LEDs, the back reflector would similarly coextend with the
`LEDs themselves and would not extend beyond or between
`the light sources to be “adjacently connected” to the light
`diffusing layer. Appellant’s Br. 46–47. Ultimately, Fire-
`bug’s argument improperly asks us to perform fact-finding.
`We are not in a position to evaluate the correctness of Fire-
`bug’s argument, but rather must determine whether the
`Board’s conclusion was supported by the evidence pre-
`sented. Holden testified that a skilled artisan would have
`been motivated to retain Parker’s back reflector for the rea-
`sons discussed above and presented a modified structure in
`which the back reflector extended beyond and between the
`individual LEDs. Further, Figure 2 of Parker illustrates
`the illumination section—including its associated back re-
`flector—extending beyond the viewing window through
`which reflected light would be visible. In light of this evi-
`dence, the Board’s determination that a person of skill
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`SHOES BY FIREBUG LLC v. STRIDE RITE CHILDREN'S GROUP
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`would be motivated to retain the back reflector in its gen-
`eral size and shape when Rosko’s LEDs are substituted for
`Parker’s optical fibers is not unreasonable.
`Second, Firebug argues that the Board improperly dis-
`regarded its argument, supported by the declaration of
`Firebug’s owner and the named inventor Roy Smith, that
`Stride Rite’s modified structure would not survive the
`“lasting” process—the process in which upper material is
`formed into the shape of a shoe—because the back reflector
`would be too weak. Appellant’s Br. 49–51. On the con-
`trary, the Board considered the argument but found it un-
`persuasive because
`it was predicated on Firebug’s
`contention that the reflective layer would be made of a thin
`layer “such as foil.” -1809 Decision, 2019 WL 236242, at
`*18; -1810 Decision, 2019 WL 237069, at *18. The Board
`also discounted Smith’s testimony because he “had not ex-
`perimented with foil, admitted that lasting forces can be
`applied by hand, and admitted that components that are
`glued together can survive the lasting process.” Id. Addi-
`tionally, Holden testified that Stride Rite’s proposed modi-
`fication would in fact increase the durability of the
`footwear. J.A. 2607 ¶ 87. The Board was within its discre-
`tion to weigh the credibility of expert testimony, see Yorkey
`v. Diab, 601 F.3d 1279, 1284 (Fed. Cir. 2010) (citing Ve-
`lander, 348 F.3d at 1371), and Firebug has not otherwise
`demonstrated that the Board’s determination is unsup-
`ported by substantial evidence.
`B. Secondary Considerations
`Firebug also argues that the Board improperly failed to
`consider certain portions of Firebug’s evidence of secondary
`considerations of nonobviousness. Specifically, Firebug ar-
`gues that the Board erred by failing to consider two license
`agreements that include the ’038 and ’574 patents as well
`as the testimony of Ralph Shanks, who negotiated the li-
`censes on behalf of the licensee. According to Firebug, the
`licenses and associated testimony from Shanks establish a
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`nexus between Firebug’s products and the challenged
`claims, which the Board otherwise found lacking. Appel-
`lant’s Br. 57.
`Stride Rite responds that even if nexus is presumed be-
`tween Firebug’s products and the challenged claims, the
`Board’s determination that Firebug’s evidence of secondary
`considerations is entitled to little weight is supported by
`substantial evidence.
`We agree with Stride Rite. The agreements presented
`by Firebug license eight patents, two patent applications,
`and one trademark to APTC LLC. J.A. 2858–79. Because
`the licenses include numerous intellectual property rights
`in addition to the ’038 and ’574 patents, the agreements on
`their face do not establish a nexus between the commercial
`interest in Firebug’s products and the claims of the ’038
`and ’574 patents. To remedy this deficiency, Firebug relies
`on the testimony of Shanks, who negotiated the license on
`behalf of APTC, that “[i]t was the ability of the Firebug
`shoes to illuminate from within that served as the primary
`driver for the license agreement.” J.A. 2180 ¶9. However,
`we need not determine whether the Board erred in deter-
`mining that Firebug had not established nexus because the
`Board alternatively found that, even if nexus is presumed,
`Firebug’s evidence of secondary considerations is weak,
`and that conclusion is supported by substantial evidence.
`Before the Board, Firebug primarily argued that evi-
`dence of industry praise, commercial success, and copying
`supports a conclusion of nonobviousness. Firebug’s evi-
`dence of industry praise rested primarily on declarations
`from Paul Barcroft, a Firebug salesman and shoe-industry
`veteran, and Smith, owner of Firebug and named inventor
`of the challenged patents. The Board struck Barcroft’s dec-
`laration because he refused to be deposed and determined
`that