Court Opinion

ID: 9931537
Source: CourtListenerOpinion
Date Created: 2024-02-09 15:01:16.584691+00
Date Added: 2024-06-11T12:23:10.828871
License: Public Domain

Case: 22-1862   Document: 37    Page: 1     Filed: 02/09/2024

   United States Court of Appeals
       for the Federal Circuit
                 ______________________

          RAI STRATEGIC HOLDINGS, INC.,
                    Appellant

                           v.

          PHILIP MORRIS PRODUCTS S.A.,
                      Appellee
               ______________________

                       2022-1862
                 ______________________

     Appeal from the United States Patent and Trademark
 Office, Patent Trial and Appeal Board in No. PGR2020-
 00071.
                  ______________________

                Decided: February 9, 2024
                 ______________________

    GREGORY A. CASTANIAS, Jones Day, Washington, DC,
 argued for appellant. Also represented by AMELIA A.
 DEGORY; ROBERT BREETZ, DAVID B. COCHRAN, KENNETH
 LUCHESI, DAVID MICHAEL MAIORANA, Cleveland, OH;
 JOSHUA R. NIGHTINGALE, Pittsburgh, PA.

     JONATHAN M. STRANG, Latham & Watkins LLP, Wash-
 ington, DC, argued for appellee. Also represented by
 GABRIEL K. BELL, MAXIMILIAN A. GRANT, DAVID ZUCKER.
                 ______________________

  Before CHEN, STOLL, and CUNNINGHAM, Circuit Judges.
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 2                           RAI STRATEGIC HOLDINGS, INC. v.
                                PHILIP MORRIS PRODUCTS S.A.

 STOLL, Circuit Judge.
     RAI Strategic Holdings, Inc. appeals the Patent Trial
 and Appeal Board’s final written decision in a post-grant
 review (PGR) holding certain claims of U.S. Patent
 No. 10,492,542 unpatentable as obvious or lacking written
 description. We affirm-in-part, vacate-in-part, and re-
 mand. Specifically, we hold that substantial evidence sup-
 ports the Board’s obviousness finding but does not support
 the Board’s finding that certain claims lack written de-
 scription support under 35 U.S.C. § 112.
                         BACKGROUND
     RAI owns the ’542 patent, which is directed to electri-
 cally powered smoking articles that provide an inhalable
 substance in vapor or aerosol form by heating tobacco or
 other substances without significant combustion. ’542 pa-
 tent col. 1 ll. 18–27.
     Claim 1 is a representative independent claim and re-
 cites:
     1. A smoking article for receiving a disposable
     aerosol forming substance, the smoking article
     comprising:
        a housing having a proximal end for receiv-
        ing the disposable aerosol forming sub-
        stance and an opposite distal end;
        a power source arranged within the hous-
        ing adjacent to the distal end;
        a receiving chamber formed at the proxi-
        mal end of the housing and having an open-
        ing for receiving the disposable aerosol
        forming substance;
        a heating projection extending at least par-
        tially in the receiving chamber towards the
        proximal end of the housing and
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         terminating at a free end which is config-
         ured to be inserted into the disposable aer-
         osol forming substance for heating the
         disposable aerosol forming substance, the
         heating projection comprising:
              a heating member comprising an
              electrically resistive metal which is
              configured to heat the disposable
              aerosol forming substance;
              an electrical connector for provid-
              ing a flow of electricity to the heat-
              ing member for heating the heating
              member; and
         a control circuit positioned within the hous-
         ing between the power source and the heat-
         ing projection and connecting the heating
         member of the heating projection to the
         power source.
 Id. at col. 42 ll. 12–37.
     Philip Morris Products, S.A. filed a petition to institute
 a PGR of claims 1–30 of the ’542 patent. In particular,
 Philip Morris asserted that these claims were invalid for
 lack of written-description support and, alternatively, ob-
 vious over Robinson 1 in view of Greim 2, either alone or in
 combination with Wang 3 or Adams 4. After the PGR was
 instituted, RAI disclaimed claims 13–17.
     Among other things, Philip Morris argued that depend-
 ent claims 10 and 27, which recite a heating member with
 “a length of about 75% to about 85% of a length of the

     1   U.S. Patent No. 7,726,320.
     2   WO 2011/050964 A1.
     3   WO 2008/139411 A2.
     4   U.S. Patent App. Pub. No. 2007/0102013.
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 4                            RAI STRATEGIC HOLDINGS, INC. v.
                                 PHILIP MORRIS PRODUCTS S.A.

 disposable aerosol forming substance,” are not supported
 by written description because “the claimed range is differ-
 ent from and substantially narrower than the ranges dis-
 closed in the specification.” Philip Morris Prods., S.A.
 v. RAI Strategic Holdings, Inc., 2022 WL 129099, at *15
 (P.T.A.B. Jan. 10, 2022) (Decision). Specifically, Philip
 Morris asserted that while the specification describes
 ranges such as 75% to 125%, 80% to 120%, 85% to 115%,
 and 90% to 110%, it does not disclose a heater length range
 with an upper limit of 85%. RAI countered that the speci-
 fication provides written description support because it
 teaches heating length embodiments at both ends of the
 claim range, pointing to the 75% to 125% and 85% to the
 110% ranges. The Board found that the claims lack written
 description support because no range contains an upper
 limit of about 85% making it “‘less clear’ that the inventors
 contemplated a range of ‘about 75% to about 85%’ as part
 of the invention.” Id. (citation omitted).
     In its final written decision, the Board held claims 1–9,
 11, 12, 18–26, and 28–30 unpatentable as obvious and
 claims 10 and 27 unpatentable for lack of adequate written
 description. Id. at *16.
     RAI appealed. We have jurisdiction under 28 U.S.C.
 § 1295(a)(4)(A).
                         DISCUSSION
     RAI raises two issues on appeal. First, RAI argues that
 the Board erred in finding that claims 10 and 27 lack ade-
 quate written description support. Second, RAI argues
 that the Board erred in finding that claims 1–9, 11, 12, 19–
 26, and 28–30 would have been obvious in view of Robinson
 as modified by Greim. We address each issue in turn.
                               I
    We begin with RAI’s written description argument.
 Specifically, RAI challenges the Board’s finding that claims
 10 and 27, which require that “the heating member is
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 present on the heating projection along a segment having
 a length of about 75% to about 85% of a length of the dis-
 posable aerosol forming substance,” lack written descrip-
 tion support under 35 U.S.C. § 112.
     The written description requirement is met when the
 disclosure relied on for support “reasonably conveys to
 those skilled in the art that the inventor had possession of
 the claimed subject matter as of the filing date.” Ariad
 Pharms., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351
 (Fed. Cir. 2010) (en banc) (citation omitted). “[T]he level of
 detail required to satisfy the written description require-
 ment varies depending on the nature and scope of the
 claims and on the complexity and predictability of the rel-
 evant technology.” Id. The test for written description re-
 quires an “objective inquiry into the four corners of the
 specification from the perspective of a person of ordinary
 skill in the art.” Id. This inquiry is a question of fact that
 we review for substantial evidence. See id.; Gen. Hosp.
 Corp. v. Sienna Biopharms., Inc., 888 F.3d 1368, 1371
 (Fed. Cir. 2018).
      Some background discussion of our precedent on writ-
 ten description support for range claims is helpful. In In re
 Wertheim, our predecessor court held that a set of claims
 that recited a narrower claimed range than the range spec-
 ified in the specification had written description support.
 541 F.2d 257, 264–65 (C.C.P.A. 1976). The case was an ap-
 peal from an interference proceeding, and the dispositive
 issue on appeal was whether certain claims of a patent ap-
 plication had written description support and therefore
 should be entitled to the filing date of the parent applica-
 tion and the applicant’s earlier Swiss application. The
 claims at issue related to a process for making freeze-dried
 instant coffee and required the solids content of the concen-
 trated coffee extract to be “between 35% and 60%” (claims
 2, 4, 37, and 38). Id. at 261–62. The specification disclosed
 a broader solids content range of 25% to 60% and provided
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                                  PHILIP MORRIS PRODUCTS S.A.

 examples of specific embodiments with solid contents of
 36% or 50%. Id. at 262.
     The Wertheim court explained that in determining
 whether the written description requirement is met,
 “[m]ere comparison of ranges is not enough,” and that in-
 stead, “we must decide whether the invention appellants
 seek to protect by their claims is part of the invention that
 appellants have described as theirs in the specification.”
 Id. at 263. And “[w]here it is clear, for instance, that the
 broad described range pertains to a different invention
 than the narrower (and subsumed) claimed range, then the
 broader range does not describe the narrower range” and
 the written description requirement would not be satisfied.
 Id. at 265. Ultimately, the court disagreed with the Board
 that the narrower claimed range of “between 35% and 60%”
 lacked written description support because that limitation
 was “within the described broad range of 25% to 60%” and
 “there [was] no evidence . . . that there [was] . . . any dis-
 tinction . . . between the claimed lower limit of solids con-
 tent and that disclosed in the Swiss application.” Id.
 at 264.
     As in Wertheim, the issue in In re Blaser was whether
 the claims had adequate written description support to be
 entitled to the filing date of a great-grandparent applica-
 tion. 556 F.2d 534, 536–37 (C.C.P.A. 1977). Our predeces-
 sor court held that the claims at issue that recited a
 narrower range than what was disclosed in the specifica-
 tion had adequate written description support. Id. at 538.
 Specifically, the claims in question were directed to a pro-
 cess for preparing acylation products of phosphorous acid
 and required heating a mixture to 80º to 200º C. Id. at 535–
 36. The court stated that “Wertheim is controlling” and
 that the specification, which disclosed heating the mixture
 to temperatures between 60º and 200º C, “adequately sup-
 port[ed] the limitation ‘80º to 200º C.’” Id. at 538.
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     In Kolmes v. World Fibers Corp., we followed a similar
 line of analysis. 107 F.3d 1534 (Fed. Cir. 1997). The claims
 at issue related to cut-resistant yarn and required two
 strands to spirally wrap the core “at the rate of 8–12 turns
 per inch.” Id. at 1537–38. The specification stated a
 broader range of wrappings formed “at the rate of 4–12
 turns per inch, with 8 turns per inch being preferred.” Id.
 at 1539. We found that the claims were “well supported by
 the specification” and accordingly, affirmed the district
 court’s finding that the claims were entitled to the parent
 application’s effective filing date. Id. at 1538–39.
      In contrast, in In re Baird, cited by the Board in its de-
 cision in this case, our predecessor court held that a
 claimed range that was narrower than the disclosed range
 lacked sufficient disclosure. 348 F.2d 974 (C.C.P.A. 1965).
 The case stemmed from an interference proceeding in
 which a patent application had copied certain claims from
 an issued patent; the issue on appeal was whether these
 claims had sufficient disclosure within the application’s
 specification. The claims in question were directed to a
 method of creating stretch-orienting polypropylene and re-
 quired a quench bath temperature range of “from about 40
 degrees F. to at least as low as about 60 degrees F.” Id.
 at 981–82. The issued patent explained the specific
 claimed range is preferred because the material would curl
 above 60º F and would be too brittle below 40º F. Id. at 982.
 The application, however, only disclosed that the quench-
 ing temperature may be between 32º F and 176º F, without
 providing any further guidance. Accordingly, the court
 found that the application’s claims lacked written descrip-
 tion support because “the copied claims ‘are drawn to an
 invention different from that disclosed in the specifica-
 tion.’” Id.
     We similarly held that a claimed range lacked written
 description support in Indivior UK Ltd. v. Dr. Reddy’s La-
 boratories S.A., also cited by the Board in its decision in
 this case. 18 F.4th 1323 (Fed. Cir. 2021). The patent
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                                  PHILIP MORRIS PRODUCTS S.A.

 application at issue in Indivior related to orally dissolvable
 films containing therapeutic agents and certain claims re-
 quired a water-soluble polymeric matrix of “about 40 wt %
 to about 60 wt %” (claim 1) or “about 48.2 wt % to about
 58.6 wt %” (claims 7 and 12). Id. at 1325–26. By contrast,
 the application’s specification alternatively disclosed a
 “film forming polymer in an amount of at least 25% by
 weight of the composition,” a polymer content of “at least
 50%,” or that “film may contain any desired level of . . . pol-
 ymer.” Id. at 1326–27, 1329. The specification also in-
 cluded tables that disclosed formulations with 48.2 wt %
 and 58.6 wt % polymer. Id. at 1326–28. We held that the
 range “about 40 wt % to about 60 wt %” lacked written de-
 scription support because (1) neither the range nor the end
 values were disclosed in the specification; and (2) the in-
 consistent statements regarding the desired amount of pol-
 ymer in the specification made it “even less clear that an
 invention of ‘about 40 wt % to about 60 wt %’ was contem-
 plated as an aspect of the invention.” Id. at 1328–29. We
 also held that the range “about 48.2 wt % to about 58.6
 wt %” lacked written description because although the end
 points were disclosed in the tables within the specification,
 there was a lack of persuasive evidence that a skilled arti-
 san would have understood the application as disclosing an
 invention with the range between these endpoints. Id.
 at 1329.
      With this background in mind, we turn to the issue be-
 fore us: whether the specification of the ’542 patent pro-
 vides written description support for a heating member
 with “a length of about 75% to about 85% of a length of the
 disposable aerosol forming substance” as required by the
 claims. ’542 patent col. 42 ll. 61–64 (claim 10), col. 44
 ll. 35–38 (claim 27). The ’542 patent specification discloses
 a broader range than that which is claimed. Specifically,
 the specification states that the electrical heating member
 present on the heating projection may have a length of
 “about 75% to about 125% the length of the inhalable
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 substance medium,” or “about 80% to about 120%, about
 85% to about 115%, or about 90% to about 110% the length
 of the inhalable substance medium.” See id. at col. 39
 ll. 41–48. The question thus is whether the disclosure of a
 length of about 75% to about 125%, about 80% to about
 120%, about 85% to about 115%, or about 90% to about
 110% “reasonably conveys to those skilled in the art that
 the inventor had possession” of the claimed length of “about
 75% to about 85%.” Ariad Pharms., Inc., 598 F.3d at 1351
 (citation omitted). Among other things, we consider
 whether “the broad described range pertains to a different
 invention than the narrower (and subsumed) claimed
 range,” in which case the specification does not provide
 written description support for the narrower claimed
 range. Wertheim, 541 F.2d at 265.
      The specification need not expressly recite the claimed
 range to provide written description support. See id.
 (“[T]he invention claimed does not have to be described in
 ipsis verbis in order to satisfy the description requirement
 of § 112 . . . .” (citation omitted)). While the ’542 patent
 specification does not disclose the claimed range itself, it
 does expressly disclose both endpoints by providing that
 the length of the heating member may be “about 75% to
 about 125%” or “about 85% to about 115%.” See ’542 patent
 col. 39 ll. 41–48 (emphases added). In addition to consid-
 ering what the specification expressly discloses, we also
 consider the context of the technology at issue and the
 knowledge gained by a person of ordinary skill in the art
 reading the specification. Given the predictability of elec-
 tro-mechanical inventions such as the one at issue here,
 and the lack of complexity of the particular claim limitation
 at issue—i.e., reciting the length of a heating member—“a
 lower level of detail is required to satisfy the written de-
 scription requirement than for unpredictable arts.” See
 Hologic, Inc. v. Smith & Nephew, Inc., 884 F.3d 1357, 1361
 (Fed. Cir. 2018). Further, nothing in the specification indi-
 cates that changing the length of the heating member
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                                  PHILIP MORRIS PRODUCTS S.A.

 changes the invention, whether as to operability, effective-
 ness, or any other parameter.
      Thus, we see no evidence suggesting that the broad de-
 scribed ranges of “about 75% to about 125%,” “about 80%
 to about 120%, about 85% to about 115%, or about 90% to
 about 110% the length of the inhalable substance medium”
 disclose a different invention than the claimed range of
 “about 75% to about 85%.” In other words, under the facts
 of this particular case, there is no evidence that the claimed
 subrange results in a different invention than the inven-
 tion disclosed in the specification. Accordingly, for all of
 the above reasons, we conclude that no reasonable fact
 finder could find that the claimed subrange is not within
 the appellant’s invention. In so holding, we note that our
 determination is highly factual and dependent on “the na-
 ture of the invention and the amount of knowledge im-
 parted to those skilled in the art by the disclosure.”
 Wertheim, 541 F.2d at 262. As we have recognized,
 “[b]roadly articulated rules are particularly inappropriate
 in this area.” Indivior, 18 F.4th at 1329–30 (alteration in
 original) (quoting Wertheim, 541 F.2d at 263).
     Though the Board relied on Indivior and Baird in its
 decision, the facts in this case align more closely with those
 in Wertheim, Blaser, and Kolmes, where the broader dis-
 closed ranges did not constitute a separate invention from
 the narrower claimed ranges. Unlike the specification in
 Indivior, the ’542 patent specification discloses the end
 points of the claimed range and there are no inconsistent
 statements regarding the range. Rather, the ’542 patent
 states a broader range for the length of the heating mem-
 ber and then states narrower ranges which are subsumed
 within that broader range. In contrast, the specification in
 Indivior stated two ranges for polymer content but then
 also stated that the polymer content could be any value. Id.
 at 1326–27, 1329. We also note that, unlike Indivior, the
 invention at issue here falls within the predictable arts.
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     Baird is likewise distinguishable from the facts here.
 In Baird, the claimed range was advantageous over the
 broad disclosed ranges because values falling outside of the
 claimed temperature range (and within the broader dis-
 closed range) caused the material to curl or be too brittle,
 and the specification did not provide any guidance to a per-
 son of skill in the art to reach the claimed range. See Baird,
 348 F.2d at 982. Thus, the court in Baird found that the
 claimed range and the disclosed range were directed to dif-
 ferent inventions. Id. Here, by contrast, there is no evi-
 dence that the ’542 patent’s disclosed range of about 75%
 to about 125% for the length of the heating member be-
 haves any differently than the claimed range of about 75%
 to about 85%.
      Philip Morris nonetheless argues that substantial evi-
 dence supports the Board’s fact finding, relying on the spec-
 ification and its expert, Dr. Seetharama Deevi.
 Specifically, Dr. Deevi testified that “[t]he described ranges
 for bulk heating are all centered on the full length (100%)
 of the inhalable substance medium,” while the claimed
 range “is not centered on 100%, but 80% (the midpoint be-
 tween about 75% and about 85%)” and, as such, “[t]here is
 nothing in the patent that would lead a [skilled artisan] to
 conclude that the inventors possessed a range that went no
 higher than 85% for bulk heating.” J.A. 2660–61 ¶¶ 124–
 125. In light of our case law and the other evidence of rec-
 ord, we do not view the expert’s testimony as evidence that
 a reasonable mind could accept as adequate to support the
 Board’s finding that a skilled artisan would not think that
 the inventor possessed a smoking article with a heating
 member with a length that is about 75% to about 85% the
 length of the inhalable substance medium.
     While it is true that the specification discloses ranges
 with values over 100% and the “about 75% to about 85%”
 range does not, our legal precedent holds that “[m]ere com-
 parison of ranges is not enough, nor are mechanical rules a
 substitute for an analysis of each case on its facts to
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                                  PHILIP MORRIS PRODUCTS S.A.

 determine whether an application conveys to those skilled
 in the art the information that the applicant invented the
 subject matter of the claims.” Wertheim, 541 F.2d at 263.
 Considering the nature of this particular smoking article
 invention and the disclosure of a wide range of lengths for
 the heating element including above and below 100%, as
 well as the lack of any explanation for why a length above
 or below 100% matters with respect to operation of the in-
 vention, skilled artisans would undoubtedly consider
 lengths that are under 100% to be part of the invention.
     Accordingly, based on the unique facts of this case, we
 find that substantial evidence does not support the Board’s
 finding that claims 10 and 27 reciting a heating member
 “present on the heating projection along a segment having
 a length of about 75% to about 85% of a length of the dis-
 posable aerosol forming substance” lack written descrip-
 tion support under § 112. We therefore vacate the Board’s
 decision on this issue and remand for further consideration
 consistent with this opinion.
                               II
     We now turn to RAI’s argument that the Board erred
 in holding that claims 1–9, 11, 12, 19–26 and 28–30 would
 have been obvious over Robinson and Greim. In particular,
 RAI challenges the Board’s fact finding that a person of
 skill in the art would have had a motivation to combine
 Robinson and Greim.
     We review the Board’s obviousness determination de
 novo and its underlying factual determinations for sub-
 stantial evidence. TQ Delta, LLC v. Cisco Sys., Inc.,
 942 F.3d 1352, 1357 (Fed. Cir. 2019). Whether a person of
 ordinary skill would have been motivated to combine prior
 art references is a question of fact. In re Gartside, 203 F.3d
 1305, 1316 (Fed. Cir. 2000). On substantial evidence re-
 view, we ask whether a reasonable fact finder could have
 arrived at the agency’s decision. Personal Web Techs., LLC
 v. Apple, Inc., 848 F.3d 987, 991 (Fed. Cir. 2017).
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      The parties agree that claim 1 is illustrative and re-
 quires a “heating projection comprising . . . an electrical
 connector for providing a flow of electricity to the heating
 member for heating the heating member.” ’542 patent
 col. 42 ll. 22–33. In its petition, Philip Morris argued that
 the combination of Robinson and Greim discloses all the
 limitations of claim 1 and specifically relied on Greim to
 disclose a heater with an “electrical connector.”
     Philip Morris asserted that a person of ordinary skill in
 the art would have been motivated to replace the heating
 element 72 in the smoking device of Robinson with Greim’s
 heater and depicted its proposed combination as shown be-
 low:

 J.A. 160 (annotations added). The figure above shows
 Greim’s heater alongside a cross-sectional view of Robin-
 son’s smoking article. Robinson’s smoking article contains
 heating element 72 extending into the tobacco segment 89.
 See Robinson, col. 27 ll. 31–39, Fig. 3.
      The following figure shows Philip Morris’s proposed
 combination in which the heater in Robinson’s smoking ar-
 ticle is replaced with Greim’s heater:
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 J.A. 160.
      Philip Morris argued to the Board that a skilled artisan
 would have been motivated to use Greim’s heater with Rob-
 inson’s smoking article because (1) Robinson discloses that
 “the size and shape of [its] heating element 72 can be al-
 tered” and that the “[s]election of the power source and re-
 sistance heating elements can be a matter of design choice,
 and will be readily apparent to one skilled in the art,”
 J.A. 163–64 (quoting Robinson, col. 27 ll. 30–39, col. 28
 ll. 41–45); and (2) Greim teaches that its heater configura-
 tion with “the necessary electronics, wiring and connec-
 tions . . . incorporated on the same electrically insulating
 substrate as the heater” has many potential advantages
 over other heaters, including being “manufactured more
 straightforwardly and cost effectively,” “requir[ing] fewer
 components in its construction,” “allowing size reduction,”
 allowing “different portions [of the aerosol-forming/tobacco
 substrate] to be heated for different durations,” and “at dif-
 ferent temperatures,” to “enhance the smoking experi-
 ence,” J.A. 165, 167–68 (second alteration in original)
 (quoting Greim, 1–4).
     The Board agreed that the language in Robinson
 “would have invited a person of ordinary skill in the art to
 apply their knowledge and skill with regard to selecting a
 resistance heating element that could be used with Robin-
 son’s housing” and thus, “a person of ordinary skill in the
 art would have had reason to look to Greim for a heater.”
 See Decision, 2022 WL 129099, at *10–11. Additionally,
 the Board acknowledged that “a person of ordinary skill in
 the art would have appreciated that Greim’s heaters pro-
 vide certain advantages, including flexibility in their de-
 sign.” Id. at *11.
     On appeal, RAI argues that contrary to the Board’s
 finding, a person of skill in the art would not have been
 motivated to combine Robinson and Greim. Specifically,
 RAI asserts that Robinson’s statements that “[o]ptionally
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 the size and shape of the second resistance heating ele-
 ment . . . can be altered” and that “[s]election of the power
 source and resistance heating elements can be a matter of
 design choice” do not invite a skilled artisan to look beyond
 Robinson to Greim. Robinson, col. 27 ll. 31–39, col. 28
 ll. 26–44. Instead, RAI maintains that these statements
 refer to alternate designs presented within Robinson itself.
 We are not persuaded.
      Substantial evidence supports the Board’s finding that
 a skilled artisan would have been motivated to replace Rob-
 inson’s heater with Greim’s heater. In light of Robinson’s
 statements about altering the heating element and the po-
 tential for design choices, the Board’s finding that Robin-
 son invites a person of skill in the art to look at other
 heating elements outside of Robinson is reasonable. Even
 if we were to agree with RAI’s interpretation of Robinson,
 the Board’s determination is further supported by Greim
 and expert testimony. The Board relied on the teachings
 of Greim, which expressly disclose advantages of its heater
 design including that it “provides flexibility in the design
 to give desired heat distribution and to heat different por-
 tions of the tobacco for different durations, at different
 times, and at different temperatures.” See Decision,
 2022 WL 129099, at *11. Additionally, the Board credited
 the testimony of Philip Morris’s expert, Dr. Deevi, who
 opined that Greim’s heater design “would facilitate more
 efficient heating of the tobacco and make it easier for a
 [person of ordinary skill in the art] to optimize the heater
 design.” See id. (alteration in original) (quoting J.A. 2678–
 79 ¶ 167).
     Further, the Board credited the testimony of RAI’s ex-
 pert, Mr. Charles Clemens, who opined that a skilled arti-
 san would have “appreciated ‘flexibility in their [heater]
 design’” and also suggested that “implementing Greim’s
 heater in Robinson’s housing would not have been beyond
 the skill of a person of ordinary skill in the art.” Id. at *11–
 12 (quoting J.A. 3677–78 (Clemens Depo. 25:19–26:6))
Case: 22-1862   Document: 37     Page: 16    Filed: 02/09/2024

 16                          RAI STRATEGIC HOLDINGS, INC. v.
                                PHILIP MORRIS PRODUCTS S.A.

 (citing Clemens Depo. 78:5–83:21). As such, we conclude
 that substantial evidence supports the Board’s finding that
 a person of ordinary skill in the art would have been moti-
 vated to replace Robinson’s heating element with the heat-
 ing element taught by Greim.
                        CONCLUSION
     For the foregoing reasons, we affirm the Board’s hold-
 ing that claims 1–9, 11, 12, 19–26 and 28–30 are unpatent-
 able as obvious. We vacate the Board’s finding that claims
 10 and 27 lack written-description support and remand for
 further proceedings consistent with this opinion.
   AFFIRMED-IN-PART, VACATED-IN-PART, AND
                 REMANDED
                           COSTS
 No costs.