Medtronic, Inc. v. Teleflex Innovations S.A.R.L.

Case: 21-2357 Document: 61 Page: 1 Filed: 06/05/2023 United States Court of Appeals for the Federal Circuit ______________________ MEDTRONIC, INC., MEDTRONIC VASCULAR, INC., Appellants v. TELEFLEX INNOVATIONS S.A.R.L., Appellee ______________________ 2021-2357, 2021-2360, 2021-2364 ______________________ Appeals from the United States Patent and Trademark Office, Patent Trial and Appeal Board in Nos. IPR2020- 00127, IPR2020-00130, IPR2020-00136. ______________________ Decided: June 5, 2023 ______________________ BRITTANY BLUEITT AMADI, Wilmer Cutler Pickering Hale and Dorr LLP, Washington, DC, argued for appel- lants. Also represented by JENNIFER L GRABER; TASHA JOY BAHAL, MARK CHRISTOPHER FLEMING, HANNAH ELISE GEL- BORT, MADELEINE C. LAUPHEIMER, Boston, MA. SANJIV P. LAUD, McCurdy LLC, Minneapolis, MN, ar- gued for appellee. Also represented by PETER M. KOHL- HEPP, TARA CATHERINE NORGARD, J. DEREK VANDENBURGH, JOSEPH W. WINKELS, Carlson, Caspers, Vandenburgh & Lindquist PA, Minneapolis, MN. Case: 21-2357 Document: 61 Page: 2 Filed: 06/05/2023 2 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. ______________________ Before MOORE, Chief Judge, LOURIE and DYK, Circuit Judges. MOORE, Chief Judge. Medtronic, Inc. and Medtronic Vascular, Inc. (collec- tively, Medtronic) appeal inter partes review decisions of the Patent Trial and Appeal Board holding Medtronic failed to establish the unpatentability of various claims of U.S. Patent Nos. 8,048,032; RE45,380; and RE45,776 (the patents-in-suit). Medtronic also appeals the Board’s deci- sions granting Teleflex Innovation S.à.r.l’s (Teleflex) mo- tions to amend certain claims of the ’032 and ’380 patents. For the following reasons, we affirm. BACKGROUND Coronary artery disease, in which plaque buildup nar- rows the lumen (i.e., the tubular cavity) of a patient’s ar- tery and obstructs blood flow, affects millions of Americans. Cardiologists refer to this narrowing of a patient’s artery as stenosis. See ’032 patent at 1:25–26. 1 For decades, car- diologists have used devices known as guide catheters to deliver interventional cardiology devices (e.g., guidewires, stents, balloon catheters) designed to alleviate stenoses. Id. at 1:15–29. Treatment typically involves inserting the guide catheter into the patient’s femoral or radial artery and guiding the catheter to the patient’s aorta until the dis- tal tip of the catheter reaches the ostium (i.e., opening) of the coronary artery. Id. at 1:30–36. Interventional devices can then be inserted into the proximal opening of the 1 The patents-in-suit share a common specification. For simplicity, all citations to the written description will refer to the ’032 patent. Case: 21-2357 Document: 61 Page: 3 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 3 catheter, advanced through the lumen of the catheter using a guidewire, and delivered past the stenosis. 2 Id. These procedures involved certain challenges and risks. For example, “[c]rossing tough lesions can create enough backward force to dislodge the guide catheter from the ostium of the artery being treated,” disrupting the pro- cedure and potentially harming the patient. Id. at 1:36– 40, 4:40–46. This problem drove practitioners to seek new catheter designs and methods with increased “back-up sup- port” that would prevent backward dislodgment of the catheter. Id. at 1:36–44. For example, one method dis- closed in a prior art journal article (Takahashi) involves a “mother-and-child” technique in which a standard 5 French guide catheter is inserted into a 6 French guide catheter and advanced until its distal tip is deep within the patient’s ostium, a technique known as deep seating. 3 Id. at 2:17–29; see J.A. 2172–76 (Takahashi). However, deep seating using standard guide catheters in the mother-and- child technique also involved risks, including that the stiff distal end of the inner catheter could damage the coronary artery when deeply embedded. ’032 patent at 2:28–44. The patents-in-suit, owned by Teleflex, sought to ad- dress these problems by using a coaxial extension catheter insertable into standard guide catheters that offered in- creased back-up support and the ability to deep seat with- out the attendant drawbacks of traditional mother-and- child systems. See id. at 2:53–3:4, 4:33–5:3. In a preferred embodiment, the disclosed extension catheter includes three parts: (1) a proximal substantially rigid portion 20 2 The proximal and distal ends of a catheter respec- tively refer to the ends nearest to and farthest from the treating physician. 3 One French is the standard unit of measurement for catheter diameters. One French equals one third of a millimeter. See J.A. 1886 ¶ 46. Case: 21-2357 Document: 61 Page: 4 Filed: 06/05/2023 4 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. (yellow); (2) a reinforced portion 18 (blue); and (3) a distal flexible tip 16 (pink). See id. at 6:9–54; see also id. at Fig. 4 (reproduced below as annotated by Medtronic’s expert). The proximal end of the guide extension catheter includes a “side opening,” i.e., a partially cylindrical region (red cir- cle), which permits the extension catheter to receive and deliver interventional cardiological devices while it is within the guide catheter. Id. at 9:44–63. As depicted in Figure 4, the side opening may include multiple inclined regions separated by a non-inclined region, a structure re- ferred to herein as a double-inclined side opening. The pa- tents-in-suit also disclose and claim embodiments in which the diameter of the extension catheter is no more than one French smaller than the diameter of the guide catheter, thereby preserving maximal volume within the coaxial lu- men for receiving interventional devices. See id. at 3:5–20. In 2009, Teleflex introduced a series of guide extension catheters embodying claims of the patents-in-suit and mar- keted as the GuideLiner V1, GuideLiner V2, and Guide- Liner V3 (collectively, the GuideLiner). Those products enjoyed undisputed commercial success and industry praise and were eventually followed by multiple, competing guide extension catheters, including Medtronic’s Telescope product, introduced in 2019. PROCEDURAL HISTORY In November of 2019, Medtronic petitioned for inter partes review of the patents-in-suit, alleging the challenged claims would have been obvious over U.S. Patent No. 5,439,445 (Kontos), which discloses a support catheter for Case: 21-2357 Document: 61 Page: 5 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 5 delivering angioplasty balloons, in view of various combi- nations of secondary references. The secondary references included: (1) U.S. Patent Application Publication No. 2004/0010280 (Adams), disclosing a catheter assembly with a distal side opening for removing embolic debris while occluding blood flow during treatment; (2) U.S. Pa- tent No. 7,604,612 (Ressemann), disclosing an evacuation sheath assembly with a distal side opening used to remove embolic material while occluding blood flow using sealing balloons; (3) U.S. Patent Application Publication No. 2005/0015073 (Kataishi), disclosing a suction catheter de- signed to remove thrombi in blood vessels; and (4) Takahashi. The Board instituted each petition and issued final written decisions holding some claims unpatentable and others not. See Medtronic, Inc. v. Teleflex Innovations S.à.r.l., No. IPR2020-00127, 2021 WL 2518685 (P.T.A.B. June 7, 2021) (’032 Decision); Medtronic, Inc. v. Teleflex In- novations S.à.r.l., No. IPR2020-00130, 2021 WL 2524006 (P.T.A.B. June 17, 2021) (’380 Decision); Medtronic, Inc. v. Teleflex Innovations S.à.r.l., No. IPR2020-00136, 2021 WL 2524191 (P.T.A.B. June 17, 2021) (’776 Decision). In addi- tion, the Board granted Teleflex’s contingent motions to amend certain claims of the ’032 and ’380 patents and de- termined the amended claims were not unpatentable. The parties organize the claims determined not un- patentable into four (overlapping) sets, a categorization we adopt for our analysis. The Side Opening Claims are claims 3, 4, 9, 13, and 18 of the ’032 patent; claims 3, 4, 9, 14, and 19 of the ’380 patent; and claims 25–27, 29, 33, 35– 37, 39, 41–49, and 52 of the ’776 patent. The One-French Claims are claims 8 and 17 of the ’032 patent; claims 8 and 18 of the ’380 patent; and claims 30–32 and 53–56 of the ’776 patent. The Double-Incline Claims are claims 52–56 of the ’776 patent. Lastly, the Substitute Claims are claims Case: 21-2357 Document: 61 Page: 6 Filed: 06/05/2023 6 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 23–25 of the ’032 patent and claims 43 and 44 of the ’380 patent. 4 DISCUSSION Medtronic appeals the Board’s determination that Medtronic failed to prove the Side Opening, One-French, and Double-Incline Claims would have been obvious. It also challenges the Board’s decision granting Teleflex’s mo- tion to introduce substitute claims. We address each issue in turn. I We first address Medtronic’s arguments that the Board erred in determining the Side Opening, Double-Incline, and One-French Claims are not unpatentable as obvious. 5 Obviousness is a question of law based on underlying facts. WBIP, LLC v. Kohler Co., 829 F.3d 1317, 1326 (Fed. Cir. 2016). We review the Board’s ultimate determination of 4 Though delineated separately, the One-French and Double-Incline Claims of the ’776 patent, as well as the Substitute Claims, also recite a side opening. 5 Teleflex contends Medtronic forfeited various argu- ments by failing to raise them in its Requests for Director Rehearing made pursuant to 37 C.F.R. § 42.71(d), which requires the petitioning party to “specifically identify all matters the party believes the Board misapprehended or overlooked.” Specifically, Teleflex argues Medtronic’s al- leged failure to comply with § 42.71(d), while not a jurisdic- tional bar to our review, grants us discretion to find unraised issues forfeited. We need not resolve this ques- tion. Even if Medtronic forfeited these arguments, an issue we do not decide, we have the discretion to reach them on appeal. Ciena Corp. v. Oyster Optics, LLC, 958 F.3d 1157, 1161 (Fed. Cir. 2020) (“[I]t is a discretionary decision to for- give waivers of non-jurisdictional challenges . . . .”). Case: 21-2357 Document: 61 Page: 7 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 7 obviousness de novo and its underlying findings of fact for substantial evidence. Id. A. SIDE OPENING CLAIMS Claim 3 of the ’032 patent is representative of the Side Opening Claims. It recites: 3. The device of claim 2 wherein the proxi- mal portion of the tubular structure further comprises structure defining a proximal side opening extending for a distance along the longitudinal axis, and accessible from a longitudinal side defined transverse to the longitudinal axis, to receive an interven- tional cardiology device into the coaxial lu- men while the proximal portion remains within the lumen of the guide catheter. ’032 patent at claim 3 (emphasis added). As relevant here, Medtronic’s petitions asserted two obviousness grounds against the Side Opening Claims: (1) Kontos in view of Adams, asserted against the claims of the ’032 and ’380 patents, and (2) Kontos in view of Ressemann, asserted against the claims of the ’776 patent. See ’032 Decision, at *4; ’380 Decision, at *3; ’776 Decision, at *3. Each ground relied on modifying Kontos’ extension catheter by removing a funnel portion at the proximal end of the catheter and replacing it with the distal side open- ings disclosed in either Adams or Ressemann. Medtronic contended a skilled artisan would be motivated to make its proposed modifications for four separate reasons related to alleged improvements in the ease and scope of use of Kon- tos’ modified device. In response, Teleflex argued Medtronic’s proposed modifications were unsupported by evidence, based on hindsight, and/or would not achieve the benefits Medtronic alleged without additional modifications not disclosed in Medtronic’s petition. In addition, Teleflex introduced Case: 21-2357 Document: 61 Page: 8 Filed: 06/05/2023 8 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. evidence of objective indicia of nonobviousness tied to its GuideLiner products, which are undisputedly embodi- ments of the Side Opening Claims. This included evidence that the GuideLiner was commercially successful, solved long-felt but unsolved needs, garnered industry praise, and was copied by competitors, including Medtronic. Medtronic’s reply acknowledged additional modifica- tions were necessary to achieve some of the alleged benefits but argued these modifications would not have deterred a skilled artisan because each was within the level of ordi- nary skill. It also disputed Teleflex’s evidence of objective indicia, arguing the evidence lacked a nexus with the Side Opening Claims and denying it had copied the GuideLiner in developing the Telescope. In its final written decisions, the Board held Medtronic failed to establish the Side Opening Claims would have been obvious. See ’032 Decision, at *21; ’380 Decision, at *21; ’776 Decision, at *16. The Board first determined the parties’ arguments regarding the references’ disclosures and motivations to combine presented a “close case.” ’032 Decision, at *20; ’380 Decision, at *14; ’776 Decision, at *9. To resolve that close prima facie case, the Board then turned to Teleflex’s objective evidence, which it found had a nexus with the Side Opening Claims. Weighing these competing considerations, the Board ultimately deter- mined Teleflex’s “strong objective evidence of nonobvious- ness” overcame the close prima facie case and that Medtronic had failed to prove the Side Opening Claims un- patentable. ’032 Decision, at *21; ’380 Decision, at *21; ’776 Decision, at *16. On appeal, Medtronic contends the Board committed a host of legal errors in its analysis of Teleflex’s objective ev- idence and the parties’ prima facie arguments. For the rea- sons given below, we conclude that the Board did not err in its analysis and that its findings are supported by substan- tial evidence. We therefore affirm the Board’s Case: 21-2357 Document: 61 Page: 9 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 9 determination that Medtronic failed to establish the Side Opening Claims would have been obvious. 1. NEXUS Medtronic first argues the Board committed legal error when it found a nexus between Teleflex’s objective evidence and the Side Opening Claims. Specifically, it contends the Board erred by finding nexus based on “three specific fea- tures [of the GuideLiner]—(1) rapid exchange functional- ity, i.e.¸ having a relatively short lumen at the distal end of the catheter; (2) increased back-up support; and (3) a side opening”—that were collectively disclosed in a single prior art reference, namely Ressemann, and therefore are not in- dicative of nonobviousness. Appellant’s Opening Br. at 68. We do not agree. As an initial matter, it is undisputed that a presump- tion of nexus applies in this case because Teleflex’s “as- serted objective evidence is tied to a specific product [i.e., the GuideLiner] and that product is the invention disclosed and claimed” by the patents-in-suit. See, e.g., ’032 Deci- sion, at *19 (internal quotation marks omitted) (quoting WBIP, 829 F.3d at 1329). As the Board explained, Med- tronic could rebut this presumption by showing Teleflex’s objective evidence resulted from features that were known, as a combination, in the prior art rather than the claimed invention as a whole. Id. The Board did not err in finding Medtronic failed to make such a showing here. The Board acknowledged Medtronic showed every ele- ment of the Side Opening Claims was individually known in the prior art but correctly concluded this did not pre- clude nexus where the evidence was “tied to the combina- tion of features as a whole” and the combination was not previously known. Id. (citing WBIP, 829 F.3d at 1331–32). Citing testimony from three of Teleflex’s experts, the Board found “it was the GuideLiner devices as a whole that re- sulted in the evidence of secondary considerations, not any individual feature in isolation.” Id. (emphasis added); see Case: 21-2357 Document: 61 Page: 10 Filed: 06/05/2023 10 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. ’380 Decision, at *20; ’776 Decision, at *15. The Board cred- ited this testimony as showing that “[w]hen the various features of the prior art were combined to form the Guide- Liner device . . . the result was a new, market-making, com- mercially successful product that provided significant benefits over prior art devices, received praise in the art, and was copied by competitors.” ’032 Decision, at *19 (em- phasis added). The Board thus explicitly grounded its nexus finding on a combination of GuideLiner features it found were not disclosed, at least as a combination, in the prior art. We detect no legal error in this analysis. Medtronic accuses the Board of legal error because, in its view, Ressemann discloses the combination of features upon which Teleflex and the Board relied in its nexus anal- ysis. While styled as a dispute of law, Medtronic’s argu- ment is merely disagreement with the Board’s fact findings. See, e.g., Med. Instrumentation & Diagnostics Corp. v. Elekta AB, 344 F.3d 1205, 1221 (Fed. Cir. 2003) (“The question of what a reference teaches and whether it describes every element of a claim is a question for the finder of fact.”); WBIP, 829 F.3d at 1331 (“Questions of nexus are highly fact-dependent . . . .”). Medtronic asserts Teleflex attributed the GuideLiner’s success to its combi- nation of rapid exchange functionality, increased back-up support, and “a side opening.” This is a mischaracteriza- tion. Teleflex and its experts did not attribute the Guide- Liner’s success to a side opening in combination with the improved functionalities. Rather, Teleflex argued the GuideLiner was successful because, in addition to offering increased back-up support and rapid exchange functional- ity, it could advantageously “receive the full array of inter- ventional cardiology devices,” an ability it grounded in “the claimed requirement that the tubular structure have a ‘co- axial lumen’ (which facilitates maximizing ‘real estate’) . . . combined with a side opening that facilitates entry of . . . [an] interventional cardiology device into the tubular por- tion.” J.A. 17611 (emphasis added); see also J.A. 23676–67 Case: 21-2357 Document: 61 Page: 11 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 11 (explaining the ability to receive the full array of cardiolog- ical devices is “reflected in the claimed requirement for a single lumen, as well as [a side opening]” (emphasis added)). Teleflex, and the Board, thus clearly relied not just on the presence of a side opening, as Medtronic contends, but on a side opening together with coaxial lumens. Indeed, Teleflex’s expert Dr. Graham clearly explained that both the coaxial lumen and proximal side opening are critical to the GuideLiner’s ability to receive the full array of inter- ventional cardiology devices. The proximal side opening allows the GuideLiner to “receive interventional cardiology devices . . . while the proximal opening was deep inside the guide catheter,” and the coaxial lumen “allow[s] the usable real estate inside the guide extension catheter to be max- imized.” J.A. 10302 ¶ 81. Thus, even if Medtronic’s allega- tion that Ressemann discloses a device with a side opening, rapid exchange functionality, and increased back-up sup- port were true, it does not show the features driving the GuideLiner’s success were disclosed in the prior art. Medtronic contends the Board’s reliance on the coaxial lumens touted by Teleflex’s experts is irrelevant because “the Board never made any finding distinguishing the claimed side opening from Ressemann.” Appellant’s Reply Br. at 27. Medtronic misunderstands the applicable bur- dens. In an inter partes review, “the petitioner shall have the burden of proving a proposition of unpatentability by a preponderance of the evidence.” 35 U.S.C. § 316(e). The absence of a finding that Ressemann does not have a coax- ial lumen therefore cannot establish Ressemann in fact has those features. 6 Medtronic also points to the Board’s 6 Medtronic’s assertion that the Board did not make any findings distinguishing the claimed side opening from Ressemann is also incorrect. In discussing Teleflex’s evi- dence of copying, the Board rejected Medtronic’s argument Case: 21-2357 Document: 61 Page: 12 Filed: 06/05/2023 12 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. finding in a related proceeding that Ressemann anticipates claims 25, 26, 28–31, 34–37, and 39 of the ’380 patent. See Medtronic, Inc. v. Teleflex Innovations S.à.r.l., No. IPR2020-00129, 2021 WL 2524890, at *11 (P.T.A.B. June 17, 2021). However, as the Board noted in that decision, those claims do not recite coaxial lumens. Id. at *7 n.9. The Board’s finding that Ressemann anticipates those claims therefore implies nothing about whether Ressemann discloses the coaxial lumens recited by the Side Opening Claims. We conclude the Board did not err in finding a nexus between Teleflex’s objective evidence and the Side Opening Claims. Medtronic does not otherwise argue that the Board’s finding, if legally proper, is not supported by sub- stantial evidence. Accordingly, we affirm the Board’s find- ing of nexus. 2. COPYING Medtronic next challenges the Board’s finding that Medtronic copied the GuideLiner in developing its own guide extension catheter, the Telescope. See ’032 Decision, at *20; ’380 Decision, at *21; ’776 Decision, at *16. The Board found Medtronic copied the GuideLiner based on its findings that (1) Medtronic had access to the GuideLiner that Teleflex could not show copying of the GuideLiner, as opposed to the prior art, because Ressemann is also “a rapid exchange device and has a side opening.” ’032 Deci- sion, at *21. The Board found this argument unavailing because the copying product “did not merely apply the idea of rapid exchange or the use of a side opening,” as taught by Ressemann, but instead “reproduce[d] the entire combi- nation of features that were assembled for the first time by the GuideLiner products.” Id. The Board thus rejected any contention that Ressemann disclosed the full combination of features utilized by the GuideLiner. Case: 21-2357 Document: 61 Page: 13 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 13 while it was developing the Telescope and the products have substantially similar designs, and (2) there was “di- rect evidence” Teleflex had copied “at least a portion of the GuideLiner device.” See, e.g., ’032 Decision, at *20. Med- tronic argues the Board’s reliance on substantial similarity between the GuideLiner and Telescope products to infer copying evinces legal error. In Medtronic’s view, evidence of substantial similarity is “irrelevant” because it does not show that Medtronic “actually copied” the GuideLiner when developing the Telescope. Appellant’s Opening Br. at 64. Under a correct view of the law, Medtronic argues, the Board “identified no evidence of actual copying efforts” and therefore its finding of copying must be reversed. Id. “It is well established that copying by a competitor is a relevant consideration in the objective indicia analysis” and therefore “may be evidence that the patented invention is nonobvious.” Liqwd, Inc. v. L’Oreal USA, Inc., 941 F.3d 1133, 1137 (Fed. Cir. 2019). The fact that a competitor cop- ied the patentee’s invention, rather than one within the public domain, is probative of nonobviousness because it suggests the competitor saw value in the invention that he could not achieve without copying. See, e.g., Diamond Rub- ber Co. of N.Y. v. Consol. Rubber Tire Co., 220 U.S. 428, 441 (1911). “Copying may indeed be another form of flattering praise for inventive features” of a patented product, Crocs, Inc. v. Int’l Trade Comm’n, 598 F.3d 1294, 1311 (Fed. Cir. 2010), but one undertaken at the risk of infringement. These rationales only apply, of course, if the alleged copyist has in fact copied the patented product rather than independently arrived at a similar design. Indeed, a com- petitor’s independent and contemporaneous development of a similar product may, in some cases, even suggest the patented product would have been obvious. Lindemann Maschinenfabrik GMBH v. Am. Hoist & Derrick Co., 730 F.2d 1452, 1460 (Fed. Cir. 1984) (“[T]he possibility of near simultaneous invention by two or more equally talented in- ventors working independently . . . may or may not be an Case: 21-2357 Document: 61 Page: 14 Filed: 06/05/2023 14 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. indication of obviousness when considered in light of all the circumstances.”). It is also clear that the copying inquiry involves a comparison of the competitor’s product with the allegedly copied patented product, rather than the patent’s claims, lest the “separate infringement and copying inquir- ies [collapse] into a single analysis.” Liqwd, 941 F.3d at 1137; see also Iron Grip Barbell Co. v. USA Sports, Inc., 392 F.3d 1317, 1325 (Fed. Cir. 2004) (“[C]opying requires the replication of a specific product.”). To that end, we have recognized copying must be supported by “actual evidence of copying efforts as opposed to mere allegations regarding similarities between the accused product and a patent.” Liqwd, 941 F.3d at 1337–38. We have never held, however, that copying cannot be established through evidence of access to and substantial similarity with a patented product. Indeed, in Liqwd, the very case Medtronic cites for the proposition that substan- tial similarity is irrelevant, we expressly recognized that “[e]vidence of copying may include . . . access and similarity to a patented product.” Id. at 1337; see also Cable Elec. Prods., Inc. v. Genmark, Inc., 770 F.2d 1015, 1027 (Fed. Cir. 1985) (“Access in combination with similarity can cre- ate a strong inference of copying.”), overruled on other grounds by Midwest Indus., Inc. v. Karavan Trailers, Inc., 175 F.3d 1356 (Fed. Cir. 1999). That same standard is also universally applied in the copyright context, which like- wise requires actual copying of a copyrighted work rather than similarity by happenstance. See, e.g., Walker v. Time Life Films, Inc., 784 F.2d 44, 48 (2d Cir. 1986) (“Copying may be inferred where a plaintiff establishes that the de- fendant had access to the copyrighted work and that sub- stantial similarities exist as to protectible material in the two works.”). Medtronic’s contention that the Board identified no ev- idence of actual copying is at odds with this precedent. Ev- idence of access and substantial similarity is evidence of copying. Medtronic’s argument is tantamount to requiring Case: 21-2357 Document: 61 Page: 15 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 15 that copying can be proven only by direct evidence “such as photos of patented features or disassembly of products,” Liqwd, 941 F.3d at 1137, rather than circumstantial evi- dence such as access and similarity. Our case law has never drawn any such distinction, nor would such a distinc- tion be consistent with basic principles of evidence and in- ference. Circumstantial evidence is just that—evidence. It establishes that a given fact is more likely to be true than one would otherwise believe in the absence of the evidence. Nor is circumstantial evidence second-class to direct evi- dence: “Circumstantial evidence is not only sufficient, but may also be more certain, satisfying and persuasive than direct evidence.” Michalic v. Cleveland Tankers, Inc., 364 U.S. 325, 330 (1960) (citation omitted). Here, there is more than sufficient circumstantial evi- dence to support the Board’s finding of copying. 7 See WBIP, 829 F.3d at 1336 (“Copying is a question of fact” re- viewed for substantial evidence). Teleflex’s experts “per- suasively demonstrate[d] that the . . . Telescope products, when considered as a whole, are substantially similar in design to then-existing GuideLiner products on the mar- ket, including the combined use of a flexible tip, reinforced portion, angled opening, pushrod, and rounded push tab.” ’032 Decision, at *20 (citing J.A. 10052–57 ¶¶ 231–39). Medtronic contends the Board disregarded differences be- tween the GuideLiner and Telescope in finding substantial similarity. Not so. The Board acknowledged the Telescope “differs from the GuideLiner V3 in its use of a hydrophilic coating and a round pushwire, and the ‘half pipe’ design of the two products is not identical.” Id. It simply found, again crediting Teleflex’s expert, that these differences 7 It is undisputed that the GuideLiner was publicly available on the market and accessible to Medtronic while it was developing the Telescope. Case: 21-2357 Document: 61 Page: 16 Filed: 06/05/2023 16 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. were not so significant as to preclude substantial similarity and the corresponding inference that Medtronic copied. Id. Medtronic’s argument that the Board committed legal error by relying on evidence of substantial similarity is meritless. 8 Because the Board’s finding that Medtronic copied is supported by substantial evidence, we affirm its finding that Medtronic’s copying is indicative of nonobvi- ousness. 3. ADDITIONAL OBJECTIVE INDICIA In addition to Medtronic’s copying, the Board relied on multiple other objective indicia of nonobviousness, includ- ing evidence the GuideLiner was copied by other competi- tors, enjoyed “a high level of commercial success,” “received significant praise in the industry,” and solved long-felt needs within the medical community for catheters with in- creased back-up support. 9 See, e.g., ’032 Decision, at *16– 20. Medtronic does not challenge any of these findings on appeal. Thus, having affirmed the Board’s findings of nexus and Medtronic’s copying, the Board’s findings re- lated to objective indicia remain entirely intact. The Board’s findings related to Teleflex’s objective evi- dence played a critical role in its determination that the Side Opening Claims are not unpatentable. The Board ex- pressly turned to that “strong evidence” in order to resolve 8 Medtronic also disputes the Board’s finding of “di- rect evidence” of copying on the same grounds that it dis- putes the Board’s finding of substantial similarity: that the evidence is insufficient to show actual copying. See, e.g., ’032 Decision, at *20. We reject those arguments for the same reasons. 9 The Board also considered Teleflex’s evidence that competitors licensed the patents-in-suit but found this evi- dence to have limited probative value. ’032 Decision, at *17. We therefore do not consider this evidence on appeal. Case: 21-2357 Document: 61 Page: 17 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 17 the parties’ close prima facie arguments and, on that basis, found Medtronic had failed to establish the obviousness of the Side Opening Claims. E.g., ’032 Decision, at *21. While we review the ultimate question of obviousness de novo, the Board’s finding that the objective evidence carried signifi- cant weight is entitled to deference. In re Inland Steel Co., 265 F.3d 1354, 1366 (Fed. Cir. 2001) (“[W]e give the Board broad deference in its weighing of the [objective] evidence before it.”); see also Bristol-Myers Squibb Co. v. Teva Pharms. USA, Inc., 752 F.3d 967, 978 (Fed. Cir. 2014) (“We give deference to a lower court’s factual findings regarding evidence of secondary considerations.”). “Weighing this objective evidence along with all the other evidence relevant to obviousness,” we agree with the Board’s determination that Medtronic failed to prove the Side Opening Claims obvious by a preponderance of the ev- idence. See Transocean Offshore Deepwater Drilling, Inc. v. Maersk Drilling USA, Inc., 699 F.3d 1340, 1355 (Fed. Cir. 2012) (concluding claims were nonobvious despite prima facie showing of obviousness). Even accepting Med- tronic’s arguments concerning the prior art’s disclosures and motivations to combine, the unusually strong objective evidence in this case strongly supports a determination of nonobviousness. See Stratoflex, Inc. v. Aeroquip Corp., 713 F.2d 1530, 1538–39 (Fed. Cir. 1983) (“[E]vidence of second- ary considerations may often be the most probative and co- gent evidence in the record. It may often establish that an invention appearing to have been obvious in light of the prior art was not.”). The Board found four distinct objective factors support nonobviousness, the majority of which Medtronic did not even attempt to dispute below or on appeal. These include the Board’s finding that the GuideLiner enjoyed a “high level of commercial success” and that Teleflex’s licensees “had essentially 100% of the U.S. guide extension catheter market.” ’032 Decision, at *16 (citing J.A. 10533–40 (con- fidential documents demonstrating the GuideLiner’s Case: 21-2357 Document: 61 Page: 18 Filed: 06/05/2023 18 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. commercial success)). Indeed, Medtronic’s own internal documents concede the GuideLiner “created the market” for guide extension catheters and enjoyed substantial mar- ket share. J.A. 10858. The GuideLiner’s considerable com- mercial success clearly supports a determination of nonobviousness. Demaco Corp. v. F. Von Langsdorff Li- censing Ltd., 851 F.2d 1387, 1391 (Fed. Cir. 1988) (“The commercial response to an invention is significant to deter- minations of obviousness, and is entitled to fair weight.”). The Board also relied on extensive praise within the indus- try, which touted the GuideLiner as “an elegant method to overcome” problems the industry previously considered “impossible despite the use of a highly supporting guiding catheter.” ’032 Decision, at *17 (citing J.A. 10588–843); see also ’380 Decision, at *16 (discussing evidence the Guide- Liner solved the long-felt but unmet need for a catheter that could avoid backout problems and “allow[ed] physi- cians to perform previously impossible coronary proce- dures”). That the GuideLiner solved problems the industry previously considered “impossible” is also strongly sugges- tive of nonobviousness. WBIP, 829 F.3d 1335 (“If industry participants or skilled artisans are skeptical about whether or how a problem could be solved . . . it favors nonobvious- ness.”). Teleflex’s experts similarly testified the Guide- Liner was “a transformational and enabling device” that provided an “elegant” and “completely new” solution to problems the industry had attempted to solve for decades without success. See J.A. 10292 ¶¶ 69, 70 (Dr. Graham); J.A. 11158–64 ¶¶ 7, 9–20 (Dr. Thompson); J.A. 10487–92 ¶¶ 4–10, 12 (Dr. Azzalini). Additionally, like the Board, we find particularly per- suasive the Board’s finding that multiple competitors cop- ied the GuideLiner in developing their own guide extension catheters. WBIP, 829 F.3d at 1336 (“The fact that a com- petitor copied technology suggests it would not have been obvious.”). This finding was based not only on Teleflex’s expert testimony that the GuideLiner and competing Case: 21-2357 Document: 61 Page: 19 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 19 products were substantially similar, but also direct evi- dence showing competitors actively sought to emulate the GuideLiner. For example, Medtronic’s design documents demonstrate Medtronic purchased and tested the Guide- Liner while developing the Telescope, J.A. 10899–90, and concede it was seeking to “build its own ‘Half Pipe’ design,” J.A. 10848, “Half Pipe” being a marketing term used by Te- leflex to describe the GuideLiner’s side opening, J.A. 10565. See also J.A. 11317–33 (confidential documents comparing the GuideLiner and Telescope). Other docu- ments and testimony show other competitors likewise sought to reproduce the claimed beneficial features of the GuideLiner. See, e.g., J.A. 10887 (Boston Scientific charac- terizing its GuideZilla product as “incorporate[ing] sub- stantially equivalent device materials and design . . . [and] fundamental technology . . . as the GuideLiner V2”); J.A. 10052 ¶¶ 232–39 (Teleflex expert opining the GuideZilla and GuideLiner are substantially similar). The Board’s findings support the conclusion that Med- tronic failed to carry its burden to show obviousness. We see no legal error in the Board’s conclusion that Medtronic failed to prove the Side Opening Claims would have been obvious by a preponderance of the evidence. While we have acknowledged “[a] strong case of prima facie obviousness . . . cannot be overcome by a far weaker showing of objective indicia of nonobviousness,” Tokai Corp. v. Easton Enters., Inc., 632 F.3d 1358, 1371 (Fed. Cir. 2011), this case pre- sents the opposite scenario. The Board found Medtronic presented a “close” prima facie case, but that this showing was overcome by Teleflex’s “strong” objective evidence. We agree. 4. THE BOARD’S PRIMA FACIE ANALYSIS Medtronic’s remaining arguments regarding the Side Opening Claims take issue with the Board’s exemplary rea- sons for finding the parties’ prima facie arguments Case: 21-2357 Document: 61 Page: 20 Filed: 06/05/2023 20 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. presented a close case. Medtronic argues these reasons re- flect legal errors in the Board’s analysis. We are not per- suaded. Medtronic first contends the Board erred by allegedly ignoring two of Medtronic’s proposed motivations to com- bine. Medtronic’s petition contended a skilled artisan would be motivated to make its proposed modifications for four reasons, namely to (1) allow the outer diameter of Kon- tos’ assembly to be reduced without reducing entry area; (2) facilitate smoother insertion of interventional cardiol- ogy devices into the extension catheter; (3) reduce the force necessary to advance the extension catheter through the guide catheter while in tortuous vasculature; and (4) per- mit smoother reentry of the proximal end of the extension catheter into the guide catheter if it was extended beyond the distal tip of the guide catheter. Medtronic asserts the Board legally erred by failing to consider the latter two rea- sons in its decisions. Contrary to Medtronic’s arguments, the Board’s deci- sions do not suggest the Board ignored any proposed moti- vations to combine. The Board expressly and accurately recounted each of Medtronic’s proposed motivations and Teleflex’s responses before concluding that “upon review of the . . . arguments and supporting evidence,” the parties had presented a close case. ’032 Decision, at *20; ’380 De- cision, at *14; ’776 Decision, at *9. The Board’s express statement that it “review[ed]” and weighed the arguments it had just recounted belies Medtronic’s contention that those arguments were simply ignored. Medtronic infers the Board ignored these motivations because they do not appear in the Board’s exemplary rea- sons for finding the parties’ arguments presented a close prima facie case. See ’032 Decision, at *20 (providing “ex- ample[s]” of deficiencies in Medtronic’s arguments); ’380 Decision, at *14 (same); ’776 Decision, at *9 (same). Med- tronic’s inference is not warranted. That the Board did not Case: 21-2357 Document: 61 Page: 21 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 21 explicitly address some of Medtronic’s proposed motiva- tions in its exemplary reasons does not imply the Board ig- nored those motivations, especially where, as here, the Board had just enumerated the arguments. Nothing in the Board’s decisions suggests its examples were intended as an exhaustive list of arguments the Board considered or rejected. Indeed, if any inference is to be drawn from the absence of the allegedly ignored motivations in the Board’s exemplary criticisms, it is that the Board considered those motivations and found them more persuasive than those it explicitly decried—precisely the opposite of what Med- tronic suggests. Medtronic also suggests that, even if the Board in fact considered each motivation in reaching its determination, its failure to explicitly address every motivation in its writ- ten decisions is inconsistent with its obligations under the Administrative Procedure Act. We do not agree. While we have acknowledged “it is not adequate [for the Board] to summarize and reject arguments without explaining why [it] accepts the prevailing argument,” In re Nuvasive, Inc., 842 F.3d 1376, 1383 (Fed. Cir. 2016), we have also repeat- edly explained “the Board is not require[d] . . . to address every argument raised by a party or explain every possible reason supporting its conclusion,” Yeda Rsch. v. Mylan Pharms. Inc., 906 F.3d 1031, 1046 (Fed. Cir. 2018). The central inquiry is whether we can “reasonably discern that [the Board] followed a proper path, even if that path is less than perfectly clear.” Ariosa Diagnostics v. Verinata Health, Inc., 805 F.3d 1359, 1365 (Fed. Cir. 2015) (citing Bowman Transp., Inc. v. Arkansas-Best Freight Sys., Inc., 419 U.S. 281, 285–86 (1974)). The Board’s path in this case is discernible. The Board accurately recounted the parties’ prima facie arguments and evidence and noted those arguments made for a close case, suggesting it considered and weighed all of the argu- ments it had just recounted. The Board then went on to expressly identify the prevailing argument driving its Case: 21-2357 Document: 61 Page: 22 Filed: 06/05/2023 22 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. decision, namely the strong objective evidence of nonobvi- ousness, which it turned to “in order to resolve this close case of obviousness.” ’032 Decision, at *20; see also ’380 Decision, at *14; ’776 Decision, at *10. While the Board’s decision could have been more detailed, “we do not require perfect explanations.” In re Nuvasive, 842 F.3d at 1382. Certainly, nothing suggests the Board “entirely failed to consider an important aspect of the problem” before it. Mo- tor Vehicle Mfrs. Ass’n of U.S., Inc. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 43 (1983). Accordingly, we con- clude the Board adequately explained the grounds for its decisions. See SEC v. Chenery Corp., 318 U.S. 80, 94 (1932) (“[T]he orderly functioning of the process of review requires that the grounds upon which the administrative agency acted [are] clearly disclosed and adequately sustained.”). Medtronic also argues the Board erred in its analysis of the motivations. In each decision, the Board noted that replacing Kontos’ funnel to reduce the diameter of the cath- eter and increase the interior volume would require several additional modifications absent from Medtronic’s petition, including at least one modification that the Board found “may not have been possible in the relevant time period.” ’032 Decision, at *20; ’380 Decision, at *14; ’776 Decision, at *9. 10 Although the Board did not indicate it gave these observations particular weight in its analysis or that they led it to ultimately find a skilled artisan would not have had a reasonable expectation of success, Medtronic con- tends the Board erred in “doubting” that success. Appel- lant’s Opening Br. at 40–45. Specifically, Medtronic argues the Board’s supposed finding that a skilled artisan would not have had a reasonable expectation of success is not 10The Board’s observation that one modification may have been impossible was not included in the ’776 Decision, although Medtronic relied on the same modification in that proceeding. Case: 21-2357 Document: 61 Page: 23 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 23 supported by substantial evidence because each modifica- tion would have been routine and within the level of ordi- nary skill. The Board’s “doubts” regarding Medtronic’s proposed modifications do not indicate the Board found a skilled ar- tisan would not have had a reasonable expectation of suc- cess. Indeed, had the Board made such a finding, there would have been no need for it to rely on Teleflex’s objective evidence to resolve the case because the absence of a rea- sonable expectation of success defeats obviousness. Re- gents of Univ. of Cal. v. Broad Inst., Inc., 903 F.3d 1286, 1291 (Fed. Cir. 2018) (“An obviousness determination re- quires finding that a person of ordinary skill in the art would have been motivated to combine or modify the . . . prior art and would have had a reasonable expectation of success in doing so.” (emphasis added and citation omit- ted)). We understand the Board’s decision as concluding that, even if a skilled artisan would have been motivated to make and reasonably expected success in making the pro- posed modifications, Medtronic had not established obvi- ousness in view of Teleflex’s strong objective evidence. 11 Medtronic’s assertion that the Board’s doubts demonstrate legal error or constitute unsupported findings is thus un- persuasive. Next, Medtronic argues the Board erred as a matter of law by discounting prior art side openings intended to re- ceive interventional cardiological devices as rare. See, e.g., ’032 Decision, at *20 (noting in its exemplary criticisms that side openings used to receive interventional devices while the catheter was still in vasculature were “rare” in the prior art). We do not agree. In the circumstances of 11 To the extent the Board did make such a finding, it is supported by substantial evidence for the same reasons discussed below with respect to the One-French Claims. See infra Section I.B. Case: 21-2357 Document: 61 Page: 24 Filed: 06/05/2023 24 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. this case, the Board, as the trier of fact, could consider a feature’s rarity in finding whether there was a motivation to combine the prior art, itself a factual inquiry. 12 See, e.g., WBIP, 829 F.3d at 1327. Medtronic contends our decision in Cree precludes the Board from “dismiss[ing]” prior art disclosures because of their rarity. Appellant’s Opening Br. at 36–37 (citing In re Cree, Inc., 818 F.3d 694, 700–01 (Fed. Cir. 2016)). As an initial matter, the Board’s decisions do not suggest they “dismissed” the prior art disclosures. Rather, those deci- sions prove the Board considered the disclosures but found, as a factual matter, that their relative rarity weighed against a motivation to combine. See, e.g., ’032 Decision, at *20. In any event, the Board’s analysis is consistent with Cree. There, Cree argued the Board erred by relying on expert testimony to support a finding that a process was known in the prior art because the experts had also testi- fied the process was disfavored. 818 F.3d at 700. We re- jected that argument because the testimony plainly cut against Cree’s contention that the process was “unknown” and instead supported the Board’s finding that the process was known, even if disfavored. Id. This case presents the inverse scenario, but the Board’s reliance on Teleflex’s ex- pert testimony was no less proper. Medtronic’s petition contended that side openings were “well known” in the prior art and identified several purported examples. J.A. 17064. Teleflex responded with expert testimony explain- ing why Medtronic’s cited examples did not in fact use side openings in the manner claimed and opining such side 12 Medtronic did not raise any argument, below or on appeal, that rarity was not probative because it was due to factors unrelated to potential motivations to combine. In- stead, it argued only that the rarity of a feature is categor- ically irrelevant to whether a skilled artisan would have been motivated to incorporate it into a new design. Case: 21-2357 Document: 61 Page: 25 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 25 openings were “not well-known.” The Board did not err in taking this testimony into account when assessing the strength of Medtronic’s evidence. Testimony that a prior art feature was rare is plainly relevant to whether it was in fact well known, as Medtronic contended. Thus, the Board did not “dismiss explicit prior art” disclosures be- cause of their rarity. Appellant’s Opening Br. at 36. In- stead, it reasonably discounted Medtronic’s argument that the prevalence of side openings in prior art interventional cardiology devices contributed to a motivation to combine. See, e.g., ’032 Decision, at *15, *20. Finally, with respect to the Side Opening Claims of the ’776 patent, Medtronic contends the Board legally erred by crediting Teleflex’s expert testimony that a skilled artisan would not be motivated to replace Kontos’ funnel with Ressemann’s side opening because of significant problems it would create. See ’776 Decision, at *9. Medtronic’s accu- sation of legal error is yet again mere disagreement with the Board’s fact finding. Teleflex’s expert explained that simply slicing off Kontos’ funnel, as proposed, would intro- duce a gap between Kontos’ support catheter and the inner wall of the guide catheter, exposing an interior spring coil and significantly increasing the likelihood of the device catching. J.A. 10009–11 ¶¶ 157–59. This is consistent with Ressemann’s own disclosure that “[s]tent delivery cathe- ters . . . are particularly subject to hanging-up on the prox- imal end” of the disclosed side opening, a problem Ressemann addresses in other embodiments. See J.A. 2145 at 25:17–29. Medtronic ignores the Board’s express reli- ance on Teleflex’s expert and asserts the Board instead came to its conclusion by erroneously focusing on Ressemann’s hang-up-mitigating embodiments to the det- riment of the side opening embodiment. The Board did not ignore Ressemann’s side opening embodiment; it merely found Teleflex’s expert testimony more persuasive than Medtronic’s. That is not legal error. Case: 21-2357 Document: 61 Page: 26 Filed: 06/05/2023 26 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. For the reasons given, we affirm the Board’s holding that Medtronic failed to establish that the Side Opening Claims are unpatentable as obvious. B. ONE-FRENCH CLAIMS Claim 8 of the ’032 patent is representative of the One- French Claims. It recites: 8. The device of claim 1 wherein the cross- sectional inner diameter of the coaxial lu- men of the tubular structure is not more than one French smaller than the cross-sec- tional inner diameter of the guide catheter. ’032 patent at claim 8 (emphasis added). Medtronic asserted two obviousness grounds against the One-French Claims: (1) Kontos in view of Adams and Takahashi, asserted against the claims of the ’032 and ’380 patents, and (2) Kontos in view of Ressemann and Takahashi, asserted against the claims of the ’776 patent. ’032 Decision, at *21; ’380 Decision, at *21; ’776 Decision, at *16. As it did for the Side Opening Claims, Medtronic posited the desire for increased back-up support would mo- tivate a skilled artisan to replace Kontos’ proximal funnel with the distal side openings of Adams and Ressemann. Medtronic reasoned this modification would allow a skilled artisan to incorporate Takahashi’s five-in-six system, in which a 5-French inner catheter is inserted into a 6-French guide catheter. Teleflex opposed on the same grounds it opposed Medtronic’s arguments concerning the Side Open- ing Claims, including by identifying objective evidence of the nonobviousness of the ’776 patent One-French Claims, which also recite a side opening. It also argued removing Kontos’ funnel would result in a greater than one-French gap between the inner extension catheter and guide cathe- ter because of Kontos’ protruding marker band and base. See, e.g., ’032 Decision, at *22. In reply, Medtronic argued a skilled artisan could account for that gap by making Case: 21-2357 Document: 61 Page: 27 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 27 additional modifications not proposed in its petition, in- cluding by recessing Kontos’ marker band. Id. The Board held Medtronic failed to establish the One- French Claims would have been obvious. E.g., ’032 Deci- sion, at *22. In doing so, the Board invoked the same rea- sons it gave for concluding the Side Opening Claims were not unpatentable, namely that Medtronic failed to estab- lish it would have been obvious to replace Kontos’ proximal funnel with a side opening and that Medtronic’s reliance on new, extensive modifications in reply was more suggestive of hindsight than obviousness. Id. Additionally, with re- spect to the One-French Claims of the ’776 patent, the Board found Teleflex’s objective evidence was indicative of nonobviousness. ’776 Decision, at *18. On appeal, Medtronic argues the Board’s decision must be reversed for the same reasons it contends the Board’s analysis of the Side Opening Claims was legally erroneous. We reject those arguments for the reasons already given. Additionally, we hold the Board’s finding that Med- tronic failed to establish a reasonable expectation of suc- cess to modify Kontos to achieve the One-French Claims was neither legally erroneous nor unsupported by substan- tial evidence. See PAR Pharm., Inc. v. TWI Pharms., Inc., 773 F.3d 1186, 1196 (Fed. Cir. 2014) (“The presence or ab- sence of a reasonable expectation of success is . . . a ques- tion of fact,” reviewed for substantial evidence). The Board observed that replacing Kontos’ funnel with a side opening would “require[] significant modifications to Kontos’ de- vice, modifications that were not proposed in the Petition.” ’032 Decision, at *22; ’380 Decision, at *22; ’776 Decision, at *20. The Board explained “[t]he extensive need to mod- ify Kontos’ device in a way not suggested in the Petition supports [Teleflex’s] argument that the proposed modifica- tions are based on a hindsight desire to recreate the claimed invention, as opposed to a known need in the art for such a device.” Id. The Board did not err in discounting Case: 21-2357 Document: 61 Page: 28 Filed: 06/05/2023 28 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. modifications not presented in Medtronic’s petition as in- dicative of hindsight. It was within the Board’s discretion not to consider these untimely raised modifications. See Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1369 (Fed. Cir. 2016) (“Once the Board identi- fies new issues presented for the first time in reply, neither this court nor the Board must parse the reply brief to de- termine which, if any, parts of that brief are responsive and which are improper.”). Further, the Board explained one of the modifications not raised in Medtronic’s petition (recessing Kontos’ marker band) “may not have been possible in the relevant time period.” See, e.g., ’032 Decision, at *20. That is con- sistent with Teleflex’s expert testimony explaining recess- ing the marker band as proposed was not a realistic option as of the patents’ priority date because it would reduce the mechanical integrity of Kontos’ device and weaken the at- tachment of Kontos’ distal tip. See J.A. 5318. This is sub- stantial evidence supporting the Board’s finding. We therefore affirm the Board’s determination that Medtronic failed to prove the One-French Claims would have been ob- vious by a preponderance of the evidence. C. DOUBLE-INCLINE CLAIMS Claim 52 of the ’776 patent is representative of the Double-Incline Claims. It recites: 52. A guide extension catheter for use with a guide catheter, comprising: a substantially rigid segment; a tubular structure defining a lumen and positioned distal to the substantially rigid segment; and a segment defining a partially cylindrical opening positioned between a distal end of the substantially rigid segment and a Case: 21-2357 Document: 61 Page: 29 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 29 proximal end of the tubular structure, the segment defining the partially cylindrical opening having an angled proximal end, formed from a material having a greater flexural modulus than a flexural modulus of the tubular structure, and configured to receive one or more interventional cardiol- ogy devices therethrough when positioned within the guide catheter, wherein a cross section of the guide exten- sion catheter at the proximal end of the tubular structure defines a single lumen; wherein the segment defining the angled proximal end of the partially cylindrical opening includes at least two inclined re- gions. ’776 patent at claim 52 (emphasis added). Medtronic asserted the Double-Incline Claims would have been obvious over Kontos and Ressemann, which it argued together would have taught a catheter with a prox- imal side opening in view of Kataishi, which discloses a suction catheter with a distal tip with two inclined regions. ’776 Decision, at *18. Medtronic argued a skilled artisan would have been motivated to include Kataishi’s double- inclined opening to improve crossability and reduce kinking and because the double incline would increase the entry area of the side opening for receiving interventional devices. Id. Teleflex argued the combination would not have been obvious for the same reasons it opposed Med- tronic’s Side Opening Claims grounds. Id. Teleflex further contended a skilled artisan would not have been motivated to substitute Kataishi’s distal tip, designed to flexibly con- form to and remove thrombi, with the proximal side open- ing of the proposed Kontos-Ressemann combination, designed to receive interventional cardiological devices. Amongst other things, Teleflex submitted expert testimony Case: 21-2357 Document: 61 Page: 30 Filed: 06/05/2023 30 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. explaining such a substitution would increase kinking, not improve crossability, and have no impact on entry area, contrary to Medtronic’s proposed motivations. See, e.g., J.A. 12021 ¶ 81; J.A. 16668–72 ¶¶ 212–17. The Board held Medtronic failed to prove the Double- Incline Claims unpatentable. ’776 Decision, at *19. The Board first found Medtronic failed to provide a reasoned explanation for substituting Kataishi’s suction-improving distal tip at the proximal opening of Kontos. Id. Even granting such a reason, however, the Board found Tele- flex’s expert testimony regarding the increased chance of kinking, together with Teleflex’s objective evidence, de- feated Medtronic’s obviousness arguments. Id. On appeal, Medtronic argues the Board’s findings rest on legal error. In particular, it asserts the Board erred by (1) failing to address its argument that using Kataishi’s double incline would increase the entry area for receiving interventional devices, (2) reasoning the location of Ka- taishi’s tip vis-à-vis Kontos and Ressmann’s proposed side opening (i.e., distal vs. proximal) weighed against a moti- vation to combine, and (3) effectively requiring physical in- corporation of Kataishi into Kontos when it credited Teleflex’s expert that using Kataishi’s double-inclined tip would increase the risk of kinking. Medtronic’s arguments are unavailing. Even accepting Medtronic’s arguments concerning motivations to combine, we conclude, as above, that Teleflex’s objective evidence is sufficient to uphold the Board’s determination that Med- tronic failed to prove the Double-Incline Claims unpatent- able. We see no error in the Board’s prima facie analysis. First, with respect to Medtronic’s increased-area argu- ment, the Board’s failure to explicitly address that argu- ment does not show the Board failed to consider it. See Novartis AG v. Torrent Pharms. Ltd., 853 F.3d 1316, 1328 (Fed. Cir. 2017) (“[T]his court has said on multiple Case: 21-2357 Document: 61 Page: 31 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 31 occasions that failure to explicitly discuss every issue or every piece of evidence does not alone establish that the tribunal did not consider it.”). The Board’s alleged errors in failing to address that argument and doubting whether a skilled artisan would use Kataishi’s distal tip for a prox- imal side opening are immaterial. The Board expressly found, in the alternative, that Teleflex’s expert persua- sively testified that using Kataishi’s distal tip would in- crease the risk of kinking and that a skilled artisan therefore would not have been motivated to use that struc- ture. See ’776 Decision, at *19. Medtronic contends its ex- pert testified otherwise, but the presence of conflicting evidence does not render the Board’s finding unsupported by substantial evidence. Consolo v. Fed. Mar. Comm’n, 383 U.S. 607, 620 (1966) (“[T]he possibility of drawing two in- consistent conclusions from the evidence does not prevent an administrative agency’s finding from being supported by substantial evidence.”). Lastly, Medtronic’s contention that the Board required physical incorporation of the references is without merit. Medtronic argues the Board’s finding that kinking would discourage skilled artisans from using Kataishi’s distal tip was improperly predicated on using the materials disclosed in Kataishi. Yet, the Board’s decision makes no reference to Kataishi’s materials. Instead, the Board credited Tele- flex’s expert testimony explaining Kataishi’s tip is designed to be “highly flexible” and that high degree of flexibility “would increase the risk of kinking.” ’776 Decision, at *19 (citing J.A. 12021 ¶ 81). The Board’s decision does not demonstrate that it improperly required physical incorpo- ration. We conclude the Board did not err in its analysis and that substantial evidence supports its findings. We there- fore affirm the Board’s determination that Medtronic failed to carry its burden to prove the Double-Incline Claims would have been obvious. Case: 21-2357 Document: 61 Page: 32 Filed: 06/05/2023 32 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. D. SUBSTITUTE CLAIMS During the inter partes review proceedings for the ’032 and ’380 patents, Teleflex filed contingent motions to amend proposing certain substitute independent claims. Proposed substitute claim 23 of the ’032 patent is repre- sentative of the Substitute Claims: 23. A device for use with a standard 6 French guide catheter, the standard guide catheter having a continuous lumen ex- tending for a predefined length from a proximal end at a hemostatic valve to a dis- tal end adapted to be placed in a branch ar- tery, the continuous lumen of the guide catheter having a circular cross-sectional inner diameter sized such that interven- tional cardiology devices are insertable into and through the lumen to the branch ar- tery, the device comprising, in a distal-to- proximal direction: a flexible tip portion defining a tubular structure having a circular cross-section and a length that is shorter than the prede- fined length of the continuous lumen of the standard 6 French guide catheter, the tub- ular structure having a cross-sectional outer diameter sized to be insertable through the cross-sectional inner diameter of the continuous lumen of the guide cathe- ter and defining a coaxial lumen having a cross-sectional inner diameter of at least 0.056 inches through which interventional cardiology devices are insertable; a substantially rigid side opening that in- cludes a first inclined region, a second in- clined region, and a non-inclined concave Case: 21-2357 Document: 61 Page: 33 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 33 track between the first and second inclined regions; and a substantially rigid portion proximal of and operably connected to, and more rigid along a longitudinal axis than, the flexible tip portion and defining a rail structure without a lumen and having a maximal cross-sectional dimension at a proximal portion that is smaller than the cross-sec- tional outer diameter of the flexible tip por- tion and having a length that, when combined with the length of the flexible dis- tal tip portion, defines a total length of the device along the longitudinal axis that is longer than the length of the continuous lu- men of the guide catheter, such that when at least a distal portion of the flexible tip is extended distally of the distal end of the guide catheter, at least a portion of the proximal portion of the sub- stantially rigid portion extends proximally through the hemostatic valve in common with interventional cardiology devices that are insertable into the guide catheter. See ’032 Decision, at *24–25 (emphases added). In each proceeding, Medtronic argued the proposed substitute claims lacked adequate written description in the original application to which the ’032 and ’380 patents claim priority. In particular, Medtronic contended the sub- stitute claims encompass catheters with side openings physically separate from the substantially rigid portion, whereas the written description only describes side open- ings that were part of the substantially rigid portion. In addition, Medtronic argued the substitute claims would have been obvious over Kontos, Kataishi, and Takahashi Case: 21-2357 Document: 61 Page: 34 Filed: 06/05/2023 34 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. on the same bases it argued the Double-Incline Claims would have been obvious. 13 The Board determined the substitute claims had ade- quate written description support and would not have been obvious over Medtronic’s asserted grounds. ’032 Decision, at *26, 30–32; ’380 Decision, at *26, *30–32. On appeal, Medtronic argues the Board erred by failing to adequately address its written description arguments and by commit- ting the same legal mistakes it allegedly made in analyzing the patentability of the Double-Incline Claims. We reject Medtronic’s arguments concerning alleged errors in the Board’s analysis of Medtronic’s obviousness grounds for the same reasons we conclude the Board did not err in its analysis of the Double-Incline Claims. We further reject Medtronic’s arguments regarding lack of written description. In a parallel inter partes review pro- ceeding against related U.S. Patent RE47,379, which claims priority to the same original application at issue here, Medtronic raised identical written description argu- ments. We today affirmed the Board’s written description finding in that appeal, which resolves this issue. See 13 Medtronic also argued the substitute claims would have been obvious over U.S. Patent No. 7,736,355 (Itou) in view of Ressemann or Kataishi. On appeal, Medtronic ar- gues the Board erred by failing to address the Itou-Ka- taishi grounds. In a separate decision, we affirmed the Board’s finding in a parallel proceeding that Itou post- dates May 3, 2006, the priority date of the patents-in-suit, and consequently is not prior art. See Medtronic, Inc. v. Teleflex Innovations S.À.R.L., No. 2021-2356, 2023 WL 3606143, at *1 (Fed. Cir. May 24, 2023). We therefore need not address the Board’s alleged failure to address this ground. Case: 21-2357 Document: 61 Page: 35 Filed: 06/05/2023 MEDTRONIC, INC. v. TELEFLEX INNOVATIONS S.A.R.L. 35 Medtronic, Inc. v. Teleflex Innovations S.à.r.l., Nos. 21- 2359, 21-2362, 21-2366 (Fed. Cir. June 5, 2023). CONCLUSION We have considered the parties’ other arguments and find them unpersuasive. For the reasons given, we affirm the Board’s decisions holding the Side Opening, Double-In- cline, and One-French Claims not unpatentable and grant- ing issuance of the Substitute Claims. AFFIRMED