Court Opinion

ID: 9399507
Source: CourtListenerOpinion
Date Created: 2023-06-05 13:01:34.463279+00
Date Added: 2024-06-11T17:19:24.850782
License: Public Domain

Case: 21-2359   Document: 59    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
              ______________________

            2021-2359, 2021-2362, 2021-2366
                ______________________

     Appeals from the United States Patent and Trademark
 Office, Patent Trial and Appeal Board in Nos. IPR2020-
 00129, IPR2020-00134, IPR2020-00138.
                  ______________________

                  Decided: June 5, 2023
                 ______________________

     JENNIFER L. GRABER, Wilmer Cutler Pickering Hale
 and Dorr LLP, Washington, DC, argued for appellants.
 Also represented by BRITTANY BLUEITT AMADI; TASHA JOY
 BAHAL, MARK CHRISTOPHER FLEMING, HANNAH ELISE
 GELBORT, MADELEINE C. LAUPHEIMER, Boston, MA.

     JOSEPH W. WINKELS, Carlson, Caspers, Vandenburgh
 & Lindquist PA, Minneapolis, MN, argued for appellee.
 Also represented by PETER M. KOHLHEPP, TARA CATHERINE
 NORGARD, J. DEREK VANDENBURGH.
                  ______________________
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 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. RE45,380; RE45,760; and RE47,379 (the
 patents-in-suit). Medtronic also appeals the Board’s deci-
 sions granting Teleflex Innovation S.à.r.l’s (Teleflex) mo-
 tion to amend certain claims of the ’379 patent. 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 ’380 patent at 1:48–49. 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 1:39–52. 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 1:53–59. Interventional devices
 can then be inserted into the proximal opening of the cath-
 eter, advanced through the lumen of the catheter using a

      1   The patents-in-suit share a common specification.
 For simplicity, all citations to the written description will
 refer to the ’380 patent.
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.          3

 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 1:59–
 63, 4:56–62. 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 1:59–67. 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 2:40–51; see J.A. 2276–80 (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. ’380 patent at 2:51–56.
     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 2:9–27, 4:56–5:27. In a preferred
 embodiment, the disclosed extension catheter includes
 three parts: (1) a proximal substantially rigid portion 20
 (yellow); (2) a reinforced portion 18 (blue); and (3) a distal

     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. 1952 ¶ 50.
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 4           MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

 flexible tip 16 (pink). See id. at 6:31–7:15; see also id. at
 Fig. 4 (reproduced below as annotated by Medtronic’s ex-
 pert). The proximal end of the guide extension catheter in-
 cludes a “side opening,” i.e., a partially cylindrical region
 (red circle), which permits the extension catheter to receive
 and deliver interventional cardiological devices while it is
 within the guide catheter. Id. at 10:1–20. 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 3:28–
 49.

                    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.
 7,604,612 (Ressemann), which discloses an evacuation
 sheath assembly with a distal side opening used to aspirate
 embolic material while occluding blood flow using sealing
 balloons, in view of various combinations of secondary ref-
 erences. The secondary references included: (1) U.S. Pa-
 tent No. 5,439,445 (Kontos), which discloses a support
 catheter for delivering angioplasty balloons; (2) U.S. Patent
 Application Publication No. 2005/0015073 (Kataishi),
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.          5

 disclosing a suction catheter designed to remove thrombi
 in blood vessels; and (3) Takahashi.
     The Board instituted each petition and issued final
 written decisions holding some claims unpatentable and
 others not. Medtronic, Inc. v. Teleflex Innovations S.à.r.l.,
 No. IPR2020-00129, 2021 WL 2524890 (P.T.A.B. June 17,
 2021) (’380 Decision); Medtronic, Inc. v. Teleflex Innova-
 tions S.à.r.l., No. IPR2020-00134, Paper No. 122 (P.T.A.B.
 June 7, 2021) (’760 Decision); Medtronic, Inc. v. Teleflex In-
 novations S.à.r.l., IPR2020-00138, Paper No. 104 (P.T.A.B.
 June 7, 2021) (’379 Decision). 4,5 In addition, the Board
 granted Teleflex’s contingent motion to amend certain
 claims of the ’379 patent and determined the amended
 claims were not unpatentable. ’379 Decision, at J.A. 133–
 64.
     The parties organize the claims determined not un-
 patentable into three (overlapping) sets, a categorization
 we adopt for our analysis. The One-French Claims are
 claims 32 and 33 of the ’380 patent; claims 48 and 51–53 of
 the ’760 patent; and claims 46–51 of the ’379 patent. The
 Double-Incline Claims are claim 27 of the ’380 patent and
 claims 44, 46–48, and 51 of the ’379 patent. Lastly, the
 Substitute Claims are claims 46, 47, and 49–51 of the ’379
 patent.
                          DISCUSSION
     Medtronic appeals the Board’s determination that
 Medtronic failed to prove the One-French and Double-In-
 cline Claims would have been obvious. It also challenges
 the Board’s decision granting Teleflex’s motion to introduce

     4   The ’760 Decision is included in the Joint Appendix
 at J.A. 53–77.
     5   The ’379 Decision is included in the Joint Appendix
 at J.A. 78–167.
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 6           MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

 substitute claims in the ’379 patent. We address each issue
 in turn.
                                I
      We first address Medtronic’s arguments that the Board
 erred in determining the One-French and Double-Incline
 Claims are not unpatentable as obvious. 6 Obviousness is a
 question of law based on underlying facts. In re Gartside,
 203 F.3d 1305, 1316 (Fed. Cir. 2000). We review the
 Board’s ultimate determination of obviousness de novo and
 its underlying findings of fact for substantial evidence. Id.
                     A. ONE-FRENCH CLAIMS
    Claim 48 of the ’760 patent is representative of the
 One-French Claims. It recites:
         48. A system comprising:
         a guide catheter configured to be advance-
         able through a main blood vessel to a posi-
         tion adjacent to an ostium of a coronary
         artery, the guide catheter having a lumen
         extending from a hemostatic valve at a

     6   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 . . . .”).
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        proximal end of the guide catheter to a dis-
        tal end of the guide catheter that is adapted
        to be positioned adjacent to the ostium of
        the coronary artery;
        a guide extension catheter configured to be
        partially advanceable through the guide
        catheter and into the coronary artery, the
        guide extension catheter having a length
        such that the distal end of the guide exten-
        sion catheter is extendable through the lu-
        men and beyond the distal end of the guide
        catheter, and a proximal end of the guide
        extension catheter is extendable through
        the hemostatic valve at the proximal end of
        the guide catheter;
        the guide extension catheter including, in a
        proximal to distal direction, a substantially
        rigid segment, a segment defining a side
        opening, and a tubular structure defining a
        lumen coaxial and in fluid communication
        with the lumen of the guide catheter, the
        lumen of the tubular structure having a
        length that is shorter than the length of the
        lumen of the guide catheter and having a
        uniform cross-sectional inner diameter that
        is not more than one French size smaller
        than the cross-sectional inner diameter of
        the lumen of the guide catheter, the side
        opening extending for a distance along the
        longitudinal axis of the segment defining
        the side opening and accessible from a lon-
        gitudinal side defined transverse to the lon-
        gitudinal axis, and the side opening and
        the lumen of the tubular structure config-
        ured to receive one or more stents or bal-
        loon catheters when the segment defining
        the side opening and a proximal end
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 8           MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

         portion of the tubular structure are posi-
         tioned within the lumen of the guide cath-
         eter and the distal end of the guide
         extension catheter extends beyond the dis-
         tal end of the guide catheter;
         wherein the segment defining the side
         opening comprises a portion of the guide
         extension catheter that is more rigid than
         a distal end portion of the tubular struc-
         ture.
 ’760 patent at claim 48 (emphasis added).
      As relevant on appeal, Medtronic asserted the One-
 French Claims would have been obvious over Ressemann
 in view of Takahashi. ’380 Decision, at *3; ’760 Decision,
 at J.A. 59; ’379 Decision, at J.A. 88. Medtronic argued a
 skilled artisan would have been motivated to modify
 Ressemann by removing its sealing balloons and replacing
 its inflation lumen with a pushrod or wire so that it could
 be used as an extension catheter. See, e.g., ’380 Decision,
 at *16. Medtronic alleged a skilled artisan would be moti-
 vated to remove the sealing balloons and inflation lumen
 used to aspirate emboli because, inter alia, Ressemann
 teaches its device can also be used to deliver certain inter-
 ventional cardiological devices such as stents or angio-
 plasty balloons. Id. It further alleged a skilled artisan
 would be motivated to incorporate Takahashi’s five-in-six
 system into Ressemann as modified to achieve the in-
 creased back-up support touted by Takahashi. Id.
     Teleflex responded that Medtronic’s modifications
 would not have been obvious because they would render
 Ressemann inoperable as a catheter capable of providing
 embolic protection (i.e., preventing embolic debris from es-
 caping down the bloodstream while the embolism is being
 removed), which Teleflex alleged was the entire purpose of
 Ressemann. Id. Teleflex further argued the modifications
 were based on hindsight and that the alleged benefits could
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.          9

 not be achieved without further modifications not detailed
 in the petitions. See, e.g., ’379 Decision, at J.A. 118–19. In
 reply, Medtronic argued removing Ressemann’s sealing
 balloons would not render it inoperable for embolic protec-
 tion because other non-occlusive, distal protection devices
 could be used instead. ’380 Decision, at *16.
      The Board agreed with Teleflex and held Medtronic
 failed to establish the One-French Claims would have been
 obvious. ’380 Decision, at *16–17; ’760 Decision, at J.A. 71–
 72; ’379 Decision, at J.A. 119–21. Contrary to Medtronic’s
 position that Ressemann is a multi-purpose device, the
 Board found Ressemann’s “entire premise” was to provide
 embolic protection using sealing balloons and that Med-
 tronic’s “extensive” modifications would eliminate “the ca-
 pability of Ressemann’s aspiration catheter to act as an
 aspiration catheter.” ’379 Decision, at J.A. 120; ’380 Deci-
 sion, at *16 (finding Medtronic’s “intended-purpose-de-
 stroying modification counsels strongly against an
 obviousness determination”); ’760 Decision, at J.A. 71–72
 (same). The Board rejected Medtronic’s argument that em-
 bolic protection could be preserved through other means,
 noting Medtronic did not raise these arguments in its peti-
 tions and that the additional extensive modifications were
 further evidence of hindsight bias. E.g., ’380 Decision, at
 *17.
     On appeal, Medtronic argues the Board legally erred
 by focusing on the detrimental effects of Medtronic’s modi-
 fications to one of Ressemann’s intended purposes (embolic
 protection) to the neglect of Ressemann’s other purpose of
 delivering interventional cardiological devices. According
 to Medtronic, the Board’s reasoning conflicts with our deci-
 sion in Intel Corp. v. Qualcomm Inc., in which we held the
 “intended purpose of [a reference] does not control” the ob-
 viousness inquiry. 21 F.4th 784, 800–01 (Fed. Cir. 2021).
 We do not agree.
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 10          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

      Medtronic’s argument, although styled as a legal chal-
 lenge, is premised on an assertion of fact contrary to the
 Board’s findings, namely that Ressemann is suitable for
 procedures that do not employ occlusive sealing balloons.
 The Board did not find that Ressemann’s device was in-
 tended to function for any purpose, including delivering in-
 terventional devices, in the absence of sealing balloons.
 Rather, it found Ressemann’s “entire premise” was to use
 sealing balloons to prevent embolic flow and that removing
 the balloons would “render Ressemann completely inopera-
 ble for its stated purpose of embolic protection.” ’379 Deci-
 sion, at J.A. 120 (emphasis added) (adopting Teleflex’s
 positions). That finding is supported by substantial evi-
 dence, including Teleflex’s expert testimony that
 “Ressemann’s sealing balloons are critical to [its] goal of al-
 lowing a lesion to be treated without embolic debris being
 carried downstream” and Ressemann’s own disclosures
 emphasizing the role of sealing balloons for embolic protec-
 tion. Id. (citing J.A. 20596–97 ¶ 148; J.A. 2240–43
 (Ressemann) at 8:12–15, 12:31–53, 13:15–14:39). Med-
 tronic’s experts also acknowledged Ressemann is “directed
 to an embolic protection device” and that Ressemann’s
 sealing balloons were a “necessary part” of that function.
 J.A. 12192 at 396:20–397:20; see also ’379 Decision, at J.A.
 118 (citing Medtronic’s expert testimony that “[i]f a
 POSITA desired to only use Ressemann for delivering ther-
 apy devices, . . . Ressemann’s device would be simplified to
 eliminate the features necessary for evacuating emboli,” in-
 cluding sealing balloons).
     Medtronic contends this finding is inconsistent with
 Ressemann’s disclosures that its device can be used in
 other surgical procedures, including to deliver interven-
 tional devices. See J.A. 2239 at 6:25–34 (describing
 Ressemann’s device “is contemplated for use . . . in other
 procedures . . . where reduction or removal of a blockage in
 a blood vessel is beneficial”); J.A. 2248 at 23:8–20 (disclos-
 ing Ressemann’s evacuation sheath is “designed to allow
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 for the passage of interventional devices”). Teleflex’s ex-
 perts, however, explained that sealing balloons would still
 be used during such procedures to occlude blood flow. J.A.
 20597 ¶ 148; see also J.A. 2243 (Ressemann) at 13:15–14:39
 (discussing the use of sealing balloons to occlude blood flow
 during stent delivery). Medtronic relies on other disclo-
 sures indicating an elastomeric tube could be used in lieu
 of sealing balloons, see J.A. 2240 at 8:41–44, but this does
 not lead to a conclusion that the Board’s finding is not sup-
 ported by substantial evidence. 7 Consolo v. Fed. Mar.
 Comm’n, 383 U.S. 607, 620 (1966) (“[T]he possibility of
 drawing two inconsistent conclusions from the evidence
 does not prevent an administrative agency’s finding from
 being supported by substantial evidence.”); Velander v.
 Garner, 348 F.3d 1359, 1378 (Fed. Cir. 2003) (“If the evi-
 dence will support several reasonable but contradictory
 conclusions, we will not find the Board’s decision unsup-
 ported by substantial evidence simply because the Board
 chose one conclusion over another plausible alternative.”).
     Even if Ressemann contemplates use cases without
 sealing balloons, the Board’s reasoning does not constitute
 legal error. Medtronic contends the Board’s finding is in-
 consistent with our holding in Intel that the intended pur-
 pose of a prior art device is not dispositive of whether a
 skilled artisan would have been motivated to modify it. See
 21 F.4th at 800–01.

     7   Teleflex argues Medtronic forfeited its argument
 that sealing balloons are not mandatory because they could
 be replaced by an elastomeric tube. It also disputes, as a
 factual matter, whether inflatable elastomeric tubes are
 meaningfully distinct from sealing balloons. We will not
 resolve this factual dispute on appeal. Even if Medtronic’s
 argument is not forfeited and has a reasonable basis in fact,
 it does not compel reversal of the Board’s finding.
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 12          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

     But there is no conflict. We read the Board as finding
 that Ressemann teaches against using its device without
 sealing balloons because doing so while advancing inter-
 ventional cardiac devices like those contemplated for use
 with the challenged claims might produce safety concerns.
 See, e.g., ’380 Decision, at *8, *16 (finding that removing
 sealing balloons would undermine Ressemann’s ability to
 “capture particulate matter during a procedure,” for exam-
 ple “positioning and placing [a] stent”); J.A. 20565 ¶ 103,
 20597 ¶ 148 (Teleflex expert asserting that a person of or-
 dinary skill in the art would not “insert and deploy a bal-
 loon or stent catheter through the Ressemann device
 without first using the balloons to occlude blood flow”); ’380
 patent at abstract & 1:42–44 (invention directed at exten-
 sion catheter for use with interventional devices such as
 stents and balloon catheters).
     In other words, the Board found that removing
 Ressemann’s sealing balloons would undermine a goal it
 shares with the challenged claims—safely advancing inter-
 ventional devices to treat cardiac lesions. See ’380 Deci-
 sion, at *2 (finding that the ’380 patent is directed at guide
 catheters for advancing “a stent or balloon catheter” to
 treat a cardiac lesion); id. at *9 (finding that Ressemann
 allows surgeons to advance a “therapeutic device, such as
 a stent” to treat a cardiac lesion while collecting “dislodged
 material”); J.A. 2237 (Ressemann) (noting that procedures
 such as stent placement carry the risk “that some of the
 treated plaque will be disrupted,” and “if allowed to flow
 through the vascular system, may cause subsequent infarc-
 tions or ischemia”). Medtronic did not argue that the pro-
 cedures contemplated in the challenged claims were free
 from such risks. See, e.g., J.A. 28399–400 (arguing instead
 that Ressemann could retain the ability to catch loose
 plaque even if modified); J.A. 22129–130 (same). The
 Board reasonably recognized that modifying a device in a
 manner that would undermine a purpose it shares with the
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.        13

 challenged claims counsels against a motivation to make
 such modifications.
     Intel is both consistent with the Board’s analysis and
 distinguishable from the facts at hand. In Intel, we re-
 jected the Board’s reasoning that a proposed rationale for
 modifying a circuit was insufficient because it “would have
 resulted in the circuit not being suitable for its intended
 purpose.” 21 F.4th at 800. We explained this reasoning—
 in which the intended purpose of the device was given con-
 trolling weight—was inconsistent with the Supreme
 Court’s recognition that “common sense teaches . . . that fa-
 miliar items may have obvious uses beyond their primary
 purposes,” and with the reference’s express recognition of
 use cases compatible with the proposed modification to the
 circuit. Id. at 801 (quoting KSR Int’l Co. v. Teleflex Inc.,
 550 U.S. 398, 420 (2007)). We did not hold, however, that
 a proposed modification’s destruction of a device’s primary
 purpose is always legally irrelevant to obviousness. Such
 a conclusion is equally at odds with common sense and
 gives in to the very hindsight bias the obviousness inquiry
 is designed to avoid. Indeed, we have held it was error for
 the Board to ignore evidence that a proposed modification
 would interfere with a reference’s stated purpose. See Po-
 laris Indus. v. Arctic Cat, Inc., 882 F.3d 1056, 1061, 1067–
 69 (Fed. Cir. 2018) (vacating Board decision that failed to
 consider whether modifying prior art reference would un-
 dermine its goal, shared with the challenged claims, of con-
 structing stable all-terrain vehicles).
     The Board’s analysis was consistent with these princi-
 ples. The Board found, in the context of these patents, that
 the destruction of Ressemann’s “entire premise” “coun-
 sel[ed] strongly against” obviousness, not that it was deter-
 minative. See, e.g., ’032 Decision, at *16. The Board went
 on to consider Medtronic’s argument that embolic protec-
 tion could be achieved without sealing balloons but found
 that argument unpersuasive because it was not presented
 in Medtronic’s petition and the extensive nature of the
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 14          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

 additional proposed modifications was suggestive of hind-
 sight. 8 Id. Further, unlike in Intel, in which the reference
 contemplated use cases beyond the “intended purpose,” 21
 F.4th at 801, the Board found Ressemann’s “entire prem-
 ise” was founded on the sealing devices Medtronic’s pro-
 posed modifications would remove. We conclude the Board
 did not err in determining the destruction of Ressemann’s
 entire purpose, shared with the challenged claims, was pro-
 bative of whether Medtronic’s modifications would have
 been obvious.
     The Board did not err in determining Medtronic failed
 to carry its burden to show the One-French Claims would
 have been obvious, and substantial evidence supports its
 underlying findings of fact. Accordingly, we affirm the
 Board’s holding that Medtronic failed to establish the One-
 French Claims are unpatentable.
                  B. DOUBLE-INCLINE CLAIMS
    Claim 27 of the ’380 patent is representative of the
 Double-Incline Claims. It recites:

      8  Medtronic argues the Board legally erred and
 abused its discretion by “refusing to consider” these argu-
 ments because Medtronic properly raised them in reply to
 rebut Teleflex’s arguments. Appellant’s Opening Br. 39.
 The Board’s decisions make plain, however, that it consid-
 ered Medtronic’s arguments. See ’032 Decision, at *17 (re-
 counting and rejecting Medtronic’s reply arguments); ’760
 Decision, at J.A. 72 (same); ’379 Decision, at J.A. 121
 (same). It simply found them unpersuasive because they
 relied on extensive modifications not discussed in the peti-
 tion, suggesting they were “improperly based on a hind-
 sight desire to recreate the inventions . . . and not a known
 need in the art for such a device.” ’379 Decision, at J.A.
 121.
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.         15

         27. The system of claim 26, wherein the
         side opening includes at least two different
         inclined slopes.
 ’380 patent at claim 27 (emphasis added).
     Medtronic asserted the Double-Incline Claims would
 have been obvious over Ressemann and Kataishi. It ar-
 gued a skilled artisan would have been motivated to incor-
 porate the double-inclined shape of Kataishi’s distal tip
 into Ressemann’s proximal side opening because doing so
 would increase entry area (i.e., the area in which to insert
 interventional devices into the extension catheter) and im-
 prove crossability (i.e., the ability to advance the extension
 catheter through the guide catheter and into vasculature).
 See ’032 Decision, at *13–14; ’379 Decision, at J.A. 124–26.
     The Board found neither motivation persuasive and ac-
 cordingly held Medtronic failed to prove the Double-Incline
 Claims are unpatentable. ’380 Decision, at *14–15; ’379
 Decision, at J.A. 127–29. Specifically, crediting Teleflex’s
 expert testimony, the Board found Medtronic failed to show
 a skilled artisan would be motivated to use the shape of
 Kataishi’s distal tip for Ressemann’s proximal side opening
 because opening area does not depend on having a double-
 inclined opening and because using the shape of Kataishi’s
 distal tip in lieu of Ressemann’s proximal side opening may
 actually impair crossability by increasing the risk of
 kinking. ’380 Decision, at *14–15; ’379 Decision, at J.A.
 127–29.
      On appeal, Medtronic argues the Board’s findings rest
 on legal error. In particular, it asserts the Board erred by
 (1) concluding an alternative design choice to increase en-
 try area negated its proposed motivation to combine, (2)
 reasoning the location of Kataishi’s tip vis-à-vis Ress-
 mann’s side opening (i.e., distal vs. proximal) weighed
 against a motivation to combine, and (3) effectively requir-
 ing physical incorporation of Kataishi into Ressemann
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 when it credited Teleflex’s expert that using Kataishi’s
 double-inclined tip would increase the risk of kinking.
     Medtronic’s arguments are unavailing. First, the
 Board did not find a lack of motivation to use Kataishi’s
 double-inclined shape merely because entry area could be
 increased in other ways. The Board expressly found the
 use of a double-inclined opening is irrelevant to entry area
 because, as Teleflex’s expert testified, entry area depends
 only on the angle of the opening. See ’380 Decision, at *14
 (crediting expert testimony that “increased area is a func-
 tion of how sharp one chooses to angle the opening and does
 not depend on having a complex, multi-angle shape like
 that of Kataishi”); ’379 Decision, at J.A. 128 (same). While
 Medtronic may be correct that the entry area of Kataishi’s
 double-inclined tip is larger than Ressemann’s side open-
 ing, the Board found this is not due to Kataishi’s tip being
 doubly-inclined and that Medtronic therefore failed to
 show increasing entry area would have motivated a skilled
 artisan to incorporate this feature into Ressemann.
      The Board’s reasoning does not rest upon the existence
 of alternative designs to achieve the same ends. It rests on
 the idea that the design feature Medtronic sought to incor-
 porate—a double-inclined opening—does not achieve that
 end. Something else does, namely a sharper opening angle.
 This was not legal error. Indeed, to hold otherwise would
 countenance motivation arguments based on functionally
 irrelevant features of references that happen to exhibit a
 benefit for altogether different reasons, a recipe that would
 be ripe for hindsight abuse.
     Second, the Board did not err in finding that the al-
 leged benefits associated with Kataishi’s distal tip would
 not translate to Ressemann’s proximal opening. The Board
 relied on substantial evidence, including Teleflex’s expert
 testimony explaining that the ability of Kataishi’s tip to
 “cross tortuous vasculature is almost entirely driven by the
 design of its distal end, as that is the portion that interacts
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.        17

 with vasculature as it is being advanced” and that “[c]on-
 siderations for suctioning a thrombus into the distal open-
 ing of Kataishi, in a distal-to-proximal direction, would not
 apply to inserting interventional devices, in a proximal-to-
 distal direction, into Ressemann’s proximal opening.” ’379
 Decision, at J.A. 127 (citing J.A. 20600 ¶ 153, J.A. 12931 ¶
 193, and J.A. 12470 at 385:1–23). Given its finding that
 the benefits of Kataishi’s distal tip were tied to its distal
 location and the “lack of any teaching suggesting any inter-
 ventional devices being passed through Kataishi’s suction
 catheter,” the Board reasonably found Medtronic failed to
 carry its burden to establish a motivation to combine. Med-
 tronic again points to its contrary expert testimony that
 Kataishi teaches its shape would improve crossability even
 if applied to a proximal opening because it would improve
 the proximal opening’s ability to smoothly navigate
 through the guide catheter (as opposed to vasculature).
 But the Board’s decision to credit Teleflex’s experts over
 Medtronic’s does not render its finding unsupported by
 substantial evidence. In re Jolley, 308 F.3d 1317, 1329
 (Fed. Cir. 2002).
      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 decisions make no reference
 to Kataishi’s materials. Instead, the Board credited Tele-
 flex’s expert testimony explaining that, because
 Ressemann’s device already has an angled side opening, no
 further benefits to crossability would accrue from using a
 double-inclined opening. ’380 Decision, at *15. The Board’s
 reasoning was thus explicitly focused on the shape of Ka-
 taishi’s distal tip, not its materials. The Board further
 found that utilizing that shape would disadvantageously
 increase flexibility at Ressemann’s proximal end, “thereby
 increasing the risk of kinking.” Id. (citing J.A. 12933
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 18          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

 ¶ 197). As Kataishi’s shape is the very feature Medtronic
 sought to incorporate into Ressemann, the Board’s deci-
 sions do not demonstrate that it improperly required phys-
 ical incorporation of the references beyond that proposed
 by Medtronic.
      We conclude the Board did not err in its analysis and
 that substantial evidence supports its findings. We there-
 fore affirm its determination that Medtronic failed to carry
 its burden to prove the Double-Incline Claims would have
 been obvious.
                     C. SUBSTITUTE CLAIMS
     During the inter partes review proceedings for the ’379
 patent, Teleflex filed a contingent motion to amend propos-
 ing certain substitute claims. Proposed substitute claim
 49, which amends claim 38, is representative of the Substi-
 tute Claims:
      49. A method of forming a device adapted for use
      with a standard guide catheter having a continu-
      ous lumen extending for a predefined length, the
      method comprising:
         providing a flexible tip segment having a lu-
         men therethrough;
         providing a reinforced segment including
         one or more metallic elements covered with
         a polymer and having a uniform, fixed
         outer diameter and a lumen for coaxial
         alignment a lumen for coaxial alignment
         with the lumen of the flexible tip segment,
         said flexible tip segment and reinforced
         segment defining a tubular structure with
         a single lumen that is configured to be co-
         axial with the continuous lumen of the
         guide catheter when positioned therein,
         wherein said tubular structure has an in-
         ner diameter that is not more than about
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 MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.        19

         one French smaller than the continuous in-
         ner lumen of the guide catheter;
         providing a substantially rigid segment de-
         fining a rail structure without a lumen ex-
         tending from a proximal end portion to a
         distal end portion, wherein the substan-
         tially rigid segment is more rigid along a
         longitudinal axis than the flexible tip seg-
         ment;
         defining a side opening portion, including
         forming, in a proximal to distal direction,
         an arcuate cross-sectional shape and hemi-
         cylindrical cross-sectional shape, the side
         opening portion extending for a distance
         along a longitudinal axis of the device such
         that the side opening is accessible from a
         longitudinal side, defined transverse to the
         longitudinal axis, to receive a balloon cath-
         eter and stent; and
         arranging, in a proximal to distal direction,
         the substantially rigid segment, the side
         opening portion, the reinforced segment,
         and the flexible tip segment such that when
         the flexible tip segment is extended distally
         of a distal end of the guide catheter, the
         proximal end portion of the substantially
         rigid segment extends proximally of a prox-
         imal end of the guide catheter and the side
         opening portion is positioned within the
         continuous lumen of the guide catheter,
         whereby the reinforced segment and sub-
         stantially rigid segment are configured to
         resist forces exerted by the balloon catheter
         and stent that are passed through and be-
         yond the coaxial lumen that would other-
         wise tend to dislodge the guide catheter
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 20          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

          from a branch artery into which the rein-
          forced segment has been advanced.
 See ’379 Decision, at J.A. 137–38 (emphases added).
     Before the Board, Medtronic argued the Substitute
 Claims lacked adequate written description in the original
 application to which the ’379 patent claims priority,
 namely Application Serial No. 11/416,629. See J.A. 30456–
 97 (’629 application). In particular, Medtronic contended
 the Substitute Claims encompass catheters with side open-
 ings separate from the substantially rigid segment,
 whereas the written description only describes side open-
 ings that were part of the substantially rigid segment. In
 addition, as relevant on appeal, Medtronic argued the Sub-
 stitute Claims would have been obvious over U.S. Patent
 No. 5,439, 445 (Kontos) in view of, inter alia, Kataishi and
 Takahashi. 9
     The Board determined the Substitute Claims had ade-
 quate written description support and would not have been
 obvious over Medtronic’s asserted grounds. ’379 Decision,
 at J.A. 139–47, J.A. 162–64. On appeal, Medtronic argues
 the Board erred by finding written description support
 based on the absence of any disclosure that the location of
 the side opening was critical to the invention and by

      9   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, Med-
 tronic argues the Board erred by failing to address the Itou-
 Kataishi 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 ’379 patent, 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.
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 deferring to the examiner’s interpretation of the prosecu-
 tion history. It also argues the Board committed legal error
 when it determined Medtronic failed to show the Substi-
 tute Claims would have been obvious. We are not per-
 suaded.
      Medtronic contends the Board failed to assess whether
 the disclosures of the ’629 application would have reasona-
 bly conveyed to a skilled artisan that the applicant pos-
 sessed a catheter with a side opening separate from the
 substantially rigid segment, but this is precisely the in-
 quiry the Board undertook. The Board acknowledged writ-
 ten description requires “the patent specification [to]
 describe an invention in sufficient detail that one skilled in
 the art can clearly conclude that the inventor invented
 what is claimed” and found, after “[h]aving reviewed the
 portions of the [s]pecification referenced by [Teleflex],” that
 the specification provided adequate support. ’379 Decision,
 at J.A. 145 (quoting Cordis Corp. v. Medtronic AVE, Inc.,
 339 F.3d 1352, 1364 (Fed. Cir. 2003)). It then identified
 written disclosures and figures it found provided the nec-
 essary support, including the patent’s description that
 “[t]he rigid portion may include a cutout portion [i.e., a side
 opening] and a full circumference portion.” Id. (emphasis
 added) (quoting ’629 application at 8:18–21).
     The Board further supported its finding by noting that
 the ’629 application’s specification “does not indicate that
 putting the side opening specifically in the substantially
 rigid portion is critical to the invention” and that the appli-
 cant never asserted the location of the side opening was a
 point of novelty during prosecution. J.A. 146. Applying our
 holding in Ethicon Endo-Surgery, Inc. v. U.S. Surgical
 Corp., the Board correctly determined the absence of em-
 bodiments in the ’629 application with a side opening sep-
 arate from the rigid segment did not preclude written
 description. J.A. 146–47 (citing 93 F.3d 1572, 1582 n.7
 (Fed. Cir. 1997) (“If [the inventor] did not consider the pre-
 cise location of the [feature] to be an element of his
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 22          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

 invention, he was free to draft [the claims] broadly (within
 the limits imposed by the prior art) to exclude the lockout’s
 exact location as a limitation of the claimed invention.”)).
 As we explained in Ethicon, if the precise location of the
 side opening was not an element of the invention, claims
 that do not recite the location as a limitation are not “un-
 supported by the specification even though [they] would be
 literally infringed by undisclosed embodiments.” 93 F.3d
 at 1582 n.7; see In re Rasmussen, 650 F.2d 1212, 1215
 (CCPA 1981) (“[T]hat a claim may be broader than the spe-
 cific embodiment disclosed in a specification is in itself of
 no moment. Indeed, the statutory provision for broadened
 claims in reissue applications is intended to meet precisely
 the situation in which a patentee has claimed ‘less’ than he
 had a right to claim.”). As the Board acknowledged, writ-
 ten description requires only that a skilled artisan would
 reasonably conclude, based on the patent’s disclosures and
 the knowledge of a person skilled in the art, that the appli-
 cant possessed catheters in which the side opening could be
 located outside the rigid segment. Ariad Pharms., Inc. v.
 Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010) (en
 banc) (“[T]he test for sufficiency is whether the disclosure
 of the application relied upon reasonably conveys to those
 skilled in the art that the inventor had possession of the
 claimed subject matter as of the filing date.”). Medtronic
 has not demonstrated the Board’s findings in this regard
 constitute legal error. 10

      10  Medtronic’s argument that the Board erroneously
 deferred to the examiner’s acceptance of amendments di-
 rected to this issue, see J.A. 18718–19050, is without merit.
 The Board recounted, but did not rely, on the examiner’s
 allowance of the claim to find written description. ’379 De-
 cision, at J.A. 143–44. Instead, it expressly based its find-
 ing on “portions of the specification . . . [that] adequately
 support[] the proposed substitute claims.” Id. at J.A. 145.
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     Finally, Medtronic argues the Board erred in determin-
 ing the Substitute Claims are not unpatentable because it
 made two findings that are inconsistent with other findings
 made in this and other inter partes reviews of related pa-
 tents. First, Medtronic contends the Board contradicted its
 finding in this proceeding that Kataishi discloses a double-
 inclined side opening. Compare ’379 Decision, at J.A. 162
 (“Kataishi fails to disclose the recited Complex Side Open-
 ing feature of the proposed substitute claims”), with id. at
 J.A. 128 (“Kataishi discloses . . . [a] mutli-angled distal
 tip”). Read in context, the Board’s statements do not evince
 legal error. The Board’s full statement is as follows: “As
 discussed hereinabove in our analysis of [Medtronic’s] chal-
 lenges to original claim 44, however, we determine Ka-
 taishi fails to disclose the recited Complex Side Opening
 feature of the proposed substitute claims.” Id. at J.A. 162.
 The Board’s “finding” must therefore be read in view of its
 discussion of claim 44, which it expressly incorporated in
 the very same sentence. Critically, in analyzing claim 44,
 the Board did not rely on Kataishi’s lack of disclosure to
 hold the claim not unpatentable, 11 but instead relied on
 Medtronic’s failure to establish a motivation to incorporate
 Kataishi’s distal tip into Ressemann’s proximal side open-
 ing. See Section I.B supra. Understood in this context, the
 Board’s statement regarding Kataishi’s disclosure is best
 read to refer to the underlying lack of motivation to com-
 bine Kataishi with Kontos. We acknowledge the Board’s
 statement in this regard is imprecise. But, as we have ex-
 plained many times, “we do not require perfect explana-
 tions” of the Board, In re Nuvasive, Inc., 842 F.3d 1376,
 1382 (Fed. Cir. 2016); rather, we only require that its path
 be reasonably discernible, Ariosa Diagnostics v. Verinata
 Health, Inc., 805 F.3d 1359, 1365 (Fed. Cir. 2015). That

     11  Indeed, in analyzing claim 44, the Board recog-
 nized Kataishi discloses a double-inclined distal tip. See
 J.A. 122–23.
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 24          MEDTRONIC, INC.   v. TELEFLEX INNOVATIONS S.A.R.L.

 standard is satisfied here, where the allegedly contradic-
 tory phrase is prefaced by thorough analysis (incorporated
 by reference) elucidating the basis for the Board’s decision.
     Second, Medtronic contends the Board contradicted its
 findings in other proceedings involving related patents
 that Kontos discloses a reinforced segment. Compare ’379
 Decision, at J.A. 163 (finding Medtronic’s Kontos/Kataishi
 combination “requires modifying Kontos to achieve . . . sub-
 stitute claim 49’s limitation of ‘a reinforced segment’”),
 with Medtronic, Inc. v. Teleflex Innovations S.à.r.l., No.
 IPR2020-00127, 2021 WL 2518685, at *14 (P.T.A.B. June
 7, 2021) (finding “Kontos’s body 12 identified in Petitioner’s
 Reply are proximal to the flexible cylindrical distal tip por-
 tion and represent ‘cylindrical reinforced portions’”). This
 argument is similarly unavailing. Even if true, this would
 not require vacatur because the Board provided an alter-
 native ground for its determination that Medtronic failed
 to establish the unpatentability of proposed substitute
 claim 49, namely a lack of motivation to combine. The
 Board found Medtronic failed to establish a skilled artisan
 would have been motivated to combine Kataishi and Kon-
 tos because they disclose “different devices, used in differ-
 ent procedures, and directed to different problems that
 might be encountered during an interventional procedure.”
 ‘379 Decision, at J.A. 163 (quoting J.A. 20749 ¶ 121). Med-
 tronic does not challenge the factual bases for these find-
 ings. Accordingly, we affirm on this ground without
 deciding whether and to what effect the Board may have
 reached inconsistent findings.
                         CONCLUSION
     We have considered the parties’ other arguments and
 find them unpersuasive. For the reasons given, we affirm
 the Board’s decisions holding the Double-Incline and One-
 French Claims not unpatentable and granting issuance of
 the Substitute Claims.
                         AFFIRMED