Case: 19-2013   Document: 43     Page: 1   Filed: 05/26/2020




        NOTE: This disposition is nonprecedential.


   United States Court of Appeals
       for the Federal Circuit
                 ______________________

           SOLENIS TECHNOLOGIES, LP,
                    Appellant

                            v.

                       SNF SAS,
                        Appellee
                 ______________________

                       2019-2013
                 ______________________

     Appeal from the United States Patent and Trademark
 Office, Patent Trial and Appeal Board in No. 95/002,397.
                   ______________________

                 Decided: May 26, 2020
                 ______________________

     DAVID S. MORELAND, Meunier Carlin & Curfman, LLC,
 Atlanta, GA, for appellant. Also represented by JOHN W.
 HARBIN.

    BILLY AARON SCHULMAN, Stites & Harbison PLLC, Al-
 exandria, VA, for appellee.
                  ______________________

    Before LOURIE, REYNA, and HUGHES, Circuit Judges.
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2                       SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS



 LOURIE, Circuit Judge.
      Solenis Technologies L.P. (“Solenis”) appeals from the
 decision of the United States Patent Office Trial and Ap-
 peal Board (the “Board”) affirming the examiner’s rejection
 of claims 2–55 of U.S. Patent 6,454,902 (“the ’902 patent”)
 in an inter partes reexamination. SNF SAS v. Ciba Speci-
 ality Chems. Water Treatments Ltd., No. 2015-007695,
 2018 WL 3456088, at *1 (P.T.A.B. July 16, 2018) (“Second
 Board Decision”), reh’g denied, 2019 WL 1580145 (P.T.A.B.
 Apr. 10, 2019). For the reasons detailed below, we affirm.
                        BACKGROUND
     Generally, to make paper, an aqueous suspension
 called cellulosic stock is fed into a headbox of a papermak-
 ing machine. The process may involve the addition of “floc-
 culating” solutions, which cause the cellulosic stock to
 clump.
     The ’902 patent provides a process for making paper
 from cellulosic stock using two flocculating steps. The pro-
 cess involves forming a cellulosic suspension, flocculating
 the suspension, draining the suspension on a screen to
 form a sheet, drying the sheet, mechanically shearing it,
 and then flocculating it again.
     The parties’ arguments in this appeal focus on two
 claims: claim 10 and claim 13. In the proceedings below,
 claim 1 was cancelled, and its limitations were imported
 into amended claim 13. Claim 1 recites:
    1. A process for making paper or paper board com-
    prising forming a cellulosic suspension, flocculat-
    ing the suspension, draining the suspension on a
    screen to form a sheet and then drying the sheet,
    wherein the cellulosic suspension is flocculated by
    the addition of a water soluble cationic synthetic
    polymer of intrinsic viscosity of at least 4 dl/g,
    wherein the flocculated cellulosic suspension is
    subjected to mechanical shearing and then
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 SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS                      3



     reflocculated by a subsequent addition of a refloc-
     culating system, and in which the reflocculating
     system comprises
         i) a siliceous material and
         ii) a water soluble anionic polymer of in-
         trinsic viscosity at least 4 dl/g, and in
         which the siliceous material (i) and water
         soluble anionic polymer (ii) are added to the
         cellulosic suspension subsequent to the
         centriscreen and wherein the cationic poly-
         mer is added to a thin stock stream of the
         cellulosic suspension.
 ’902 patent col. 13 ll. 29–45 (emphases added). The “cen-
 triscreen” appears to be a shearing step, and the specifica-
 tion describes the reflocculating polymer as being added
 late in the papermaking process. Claim 13 depends from
 claim 1, reciting “[a] process according to claim 1 in which
 the water soluble anionic polymer has an intrinsic viscosity
 of at least 7 dl/g.” Id. at col. 14 ll. 33–35 (emphasis added).
      Claim 10 also depends from cancelled claim 1 and re-
 cites a process for making paper or paper board wherein
 the second flocculating step uses a “branched” “water solu-
 ble polymer which exhibits a rheological oscillation value
 of tan delta at 0.005 Hz of above 0.7 (calculated on a 1.5%
 by weight aqueous solution of the polymer).” Id. at col. 14
 ll. 22–26. All claims in this appeal rise and fall with either
 claim 10 or 13.
      SNF SAS (“SNF”) filed a request for inter partes reex-
 amination, which was ordered for claims 1–9 and 11–18.
 Solenis then cancelled claim 1, amended claim 13 to incor-
 porate its limitations, and added new claims 26–55. See
 J.A. 1553. The examiner, in his discretion, brought claim
 10 into the reexamination as well. J.A. 1511.
     The reexamination produced a series of opinions, but
 the relevant history is as follows. The examiner rejected
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4                      SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS



 claim 13 but allowed claim 10. Solenis appealed to the
 Board, and the Board affirmed the rejection of claim 13 but
 issued a new ground of rejection for claim 10. SNF SAS v.
 Ciba Speciality Chems. Water Treatments Ltd., No. 2015-
 007695, 2016 WL 4437952, at *1 (P.T.A.B. Aug. 19, 2016)
 (“First Board Decision”). Solenis requested to reopen pros-
 ecution, arguing that the Board issued a new ground of re-
 jection for both claim 10 and 13, J.A. 2046–2076, but the
 Board disagreed and declined to remand claim 13. SNF
 SAS v. Ciba Speciality Chems. Water Treatments Ltd., No.
 2015-007695 (P.T.A.B. Feb. 28, 2017) (“Remand Order”).
 On remand, the examiner allowed claim 10, but the Board
 reversed the examiner again. Second Board Decision, 2018
 WL 3456088, at *5. Solenis then moved for rehearing,
 which was denied. SNF SAS v. Ciba Speciality Chems. Wa-
 ter Treatments Ltd., No. 2015-007695, 2019 WL 1580145,
 at *1 (P.T.A.B. Apr. 10, 2019) (“Rehearing Decision”).
     Relevant to this appeal are three references:
 WO 98/24973 (“WO ’973”); European Patent Application
 EP 0877120 A1 (“EP ’120”); and U.S. Patent 5,958,188
 (“the ’188 patent”). WO ’973 discloses a process for making
 paper wherein a “main aqueous flow” of cellulosic fibers
 and filler are fed into the headbox. WO ’973 at 3. The main
 flow comprises at least a “high consistency” (HC) flow and
 a “low consistency” (LC) flow. Id. A cationic polymer is
 introduced into the HC flow as a retention agent. Id. at 8.
 WO ’973 specifies that cationic acrylamide-based polymers
 are preferred. Id. at 6. The LC flow may include an “addi-
 tive” that may comprise an anionic polymer. The molecular
 weight of the “main polymer” is “usually above 200,000,
 suitably above 300,000, preferably at least 500,000 and
 most preferably at least 1,000,000.” Id. The polymer
 weight is below about 20,000,000. Id.
     EP ’120 teaches a papermaking process that uses an
 ionic water-soluble polymer produced by dispersion
 polymerization. The disclosure teaches a method for pro-
 ducing the polymer by polymerizing water-soluble, ionic,
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 SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS                      5



 vinyl monomers under agitation in a salt solution. The
 “polymerization mechanism” is not described, but the ap-
 plication states that “it is assumed that a polymer having
 a specific molecular structure, such as a branched polymer
 or block copolymer, is produced” and that “the specific mo-
 lecular structure” of the produced polymer “is a primary
 factor of improving retention and/or drainage.” EP ’120 at
 4.
      The ’188 patent teaches a process for making paper
 where a polymer is made by reacting monomers. The spec-
 ification explains that “one way of indicating that [a]
 branched polymer is in solution . . . rather than being in
 the form of cross linked particles is by observing that the
 defined tan delta value is relatively high (above 0.5 and
 preferably above 0.7).” ’188 patent col. 4. ll. 26–36.
     The Board’s merits determinations for two claims are
 relevant to this appeal: (1) the rejection of claim 13 based
 on the Board’s finding that WO ’973 discloses a cationic pol-
 ymer with an intrinsic viscosity of at least 4 dl/g and an
 anionic polymer with an intrinsic viscosity of at least 7 dl/g;
 and (2) the rejection of claim 10 based on the Board’s find-
 ing that EP ’120 in view of the ’188 patent teaches a
 branched, water-soluble cationic polymer with a rheologi-
 cal oscillation value of tan delta at 0.005 Hz of above 0.7.
 The examiner considered both issues in the first instance.
     The examiner relied on WO ’973 to teach both cationic
 and anionic polymers of the claimed intrinsic viscosities in
 claim 13. The examiner calculated the intrinsic viscosity
 of poly(N,N’-dimethylacrylamide) with a weight range of
 50,000 to 1.22 million, treating it as representative of both
 the cationic and anionic polymers of WO ’973.
     To calculate the intrinsic viscosity of the prior art ma-
 terials, the examiner used the Mark-Houwink-Sakurada
 (MHS) equation:
                          [n] = KMa.
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6                       SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS



 In the MHS equation, “[n]” is the intrinsic viscosity, “K” is
 a constant in dl/g, and “M” is the molecular weight. Relying
 on “K” and “a” values from the Polymer Handbook, 1 the ex-
 aminer calculated the intrinsic viscosity of poly(N,N’-dime-
 thylacrylamide) as 16.8 dl/g. According to the examiner’s
 determination, the intrinsic viscosity of WO ’973’s “pre-
 ferred polymer” (i.e., an acrylamide-based polymer) at the
 preferred molecular weight met both claimed viscosity lim-
 itations.
     Regarding claim 10, the examiner relied on a combina-
 tion of WO ’973, EP ’120, and the ’188 patent. The exam-
 iner found that WO ’973 teaches an LC flow, which may
 comprise an anionic polymer and preferably an acrylamide-
 based polymer with a molecular weight above 1 million.
 Relying on the value calculated above for poly(N,N’-dime-
 thylacrylamide), the examiner found that the anionic poly-
 mer would also have an intrinsic viscosity of at least 16.8
 dl/g. But the examiner ultimately found claim 10 would
 not have been obvious because there was no disclosure in
 EP ’120 or the ’188 patent showing a cationic water-soluble
 polymer with the claimed rheological oscillation value.
      On appeal, the Board affirmed the examiner’s decision
 regarding intrinsic viscosity and claim 13. The Board spe-
 cifically agreed with the examiner’s reliance on poly(N,N’-
 dimethylacrylamide) as representative for cationic poly-
 mers because WO ’973 discloses cationic acrylamide-based
 polymers as particularly preferred with molecular weights
 of at least 1 to about 20 million. 2 The Board found no


     1   POLYMER HANDBOOK, IV-21 (J. Brandrup & E.H.
 Immergut eds., 1966).
     2   The Board also commented that high molecular
 weight cationic polymers used in retention systems are
 characterized by intrinsic viscosities of about 4 dl/g and
 that such cationic polymers have molecular weights above
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 SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS                     7



 evidence of record suggesting that poly(N,N’-dime-
 thylacrylamide) could not be used as an example of an
 acrylamide-based polymer sufficient to establish the rela-
 tionship between intrinsic viscosity and molecular weight
 with respect to the polymers described in WO ’973. The
 Board also commented that Solenis had not explained why
 a cationic polymer would have a significantly different K
 value. Citing that WO ’973 discloses anionic polymers of
 similarly     high     weights—most      preferably     above
 10,000,000—the Board extended its conclusion for the in-
 trinsic viscosity of the cationic polymer to the anionic poly-
 mer. First Board Decision, 2016 WL 4437952, at *7–8.
     Regarding claim 10, the Board held that EP ’120 dis-
 closes water-soluble ionic polymers that are either
 branched polymers or block copolymers, which is the pri-
 mary factor in improving retention or drainage. Thus, the
 Board read EP ’120 to teach branched cationic polymers.
 Then, relying on the ’188 patent, the Board held that a
 branched polymer in solution has a relatively high tan
 delta value, above 0.5 and preferably above 0.7. Thus, the
 Board held that EP ’120 discloses water-soluble polymers,
 which would have a relatively high rheological oscillation
 value. In the Board’s view, the value taught by the prior
 art matched that in the claims because the ’188 patent ex-
 pressly teaches that a tan delta of above 0.7 is preferred.
 Thus, the Board entered a new rejection of claim 10 as ob-
 vious over WO ’973 and EP ’120.
     On remand to the examiner, Solenis submitted a dec-
 laration from its expert, Christian Jehn-Rendu, and the ex-
 aminer relied on the declaration to find that EP ’120
 discloses a polymer in a dispersion, and polymers in


 500,000, but this finding was vacated on rehearing to make
 clear that the Board was affirming the examiner’s ra-
 tionale and not providing a new basis for rejection. Rehear-
 ing Decision, 2019 WL 1580145, at *2.
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8                       SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS



 dispersions have a tan delta value of less than 0.5, outside
 the scope of the claim.
     On appeal from that decision, the Board reversed. It
 found that EP ’120 did disclose a method for producing wa-
 ter-soluble cationic polymers by dispersion polymerization,
 but the dispersion was produced during polymer formula-
 tion. Ultimately, in the Board’s view, the process yielded a
 water-soluble polymer. Alternatively, the Board also found
 that, even if the claim’s oscillation value was not inherent
 in the water-soluble branched polymers of EP ’120, it would
 have been obvious to select a branched water-soluble poly-
 mer as taught by EP ’120 because of the desire for a water-
 soluble, easily-dissolvable cationic polymer. According to
 the Board, a “skilled artisan would seek to utilize a fine
 cationic polymer exhibiting a tan delta above 0.7 due to the
 express disclosure in the ’188 patent that polymer systems
 having a tan delta value above 0.7 have more soluble poly-
 mer and less cross-linked polymer.” Second Board Deci-
 sion, 2018 WL 3456088 at *5.
     Solenis moved for rehearing on all the above issues, but
 the Board reiterated its previous reasoning and denied re-
 hearing. Solenis appealed, and we have jurisdiction under
 28 U.S.C. § 1295(a)(4)(A).
                         DISCUSSION
     We review the Board’s legal determinations de novo, In
 re Elsner, 381 F.3d 1125, 1127 (Fed. Cir. 2004), and its fact
 findings for substantial evidence, In re Gartside, 203 F.3d
 1305, 1316 (Fed. Cir. 2000). A finding is supported by sub-
 stantial evidence if a reasonable mind might accept the ev-
 idence as sufficient to support the finding. Consol. Edison
 Co. v. NLRB, 305 U.S. 197, 229 (1938).
     Obviousness is a question of law, supported by under-
 lying fact questions. In re Baxter Int’l, Inc. 678 F.3d 1357,
 1361 (Fed. Cir. 2012). In evaluating obviousness, we con-
 sider the scope and content of the prior art, differences
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 SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS                     9



 between the prior art and the claims at issue, the level of
 ordinary skill in the pertinent art, and any relevant sec-
 ondary considerations. Graham v. John Deere Co. of Kan.
 City, 383 U.S. 1, 17–18 (1966).
     “The inherent teaching of a prior art reference, a ques-
 tion of fact, arises both in the context of anticipation and
 obviousness.” In re Napier, 55 F.3d 610, 613 (Fed. Cir.
 1995) (citing In re Grasselli, 713 F.2d 731, 739 (Fed. Cir.
 1983)). The use of inherency, however, “must be carefully
 circumscribed in the context of obviousness.” PAR Pharm.,
 Inc. v. TWI Pharm., Inc., 773 F.3d 1186, 1195 (Fed. Cir.
 2014) (first citing In re Rijckaert, 9 F.3d 1531, 1533–34
 (Fed. Cir. 1993); then citing In re Oelrich, 666 F.2d 578, 581
 (C.C.P.A. 1981); and then citing Application of Shetty, 566
 F.2d 81, 86 (C.C.P.A. 1977)).
     Solenis raises two arguments on appeal: (1) that the
 Board’s determinations regarding claims 10 and 13 lack
 substantial evidence; and (2) that the Board erred in failing
 to consider the Jehn-Rendu declaration in its review of the
 intrinsic viscosity limitation of claim 10 after prosecution
 was reopened. We address each issue in turn.
                               A.
     Solenis argues that the Board’s determinations for
 claim 13’s intrinsic viscosity limitations and claim 10’s rhe-
 ological oscillation value limitation lack substantial evi-
 dence.
     First, Solenis challenges the examiner’s and the
 Board’s analysis regarding claim 13. According to Solenis,
 the examiner failed to provide sufficient detail concerning
 his MHS equation calculation and did not adequately ex-
 plain why poly(N,N’-dimethylacrylamide) was representa-
 tive of all cationic and anionic polyacrylamides. Thus, in
 Solenis’s view, the examiner failed to show that WO ’973
 necessarily and inherently discloses cationic and anionic
 polyacrylamides of the claimed intrinsic viscosities. SNF
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 10                      SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS



 responds that the Board’s decisions are supported by sub-
 stantial evidence and that the Board properly analyzed the
 record.
     We agree with SNF. WO ’973 discloses cationic and
 anionic polymers with molecular weights of above 1 mil-
 lion. See WO ’973 at 6 (“Examples of suitable main poly-
 mers include anionic, amphoteric and cationic acrylamide-
 based polymers . . . . The molecular weight of the main pol-
 ymer is usually above 200,000 . . . and most preferably at
 least 1,000,000.”). Selection of an acrylamide-based poly-
 mer like poly(N,N’-dimethylacrylamide) was reasonable on
 this record as acrylamides were designated in WO ‘973 as
 preferred. Solenis may disagree with the examiner and
 Board’s designation of poly(N,N’-dimethylacrylamide) as
 representative, but the selection certainly meets the sub-
 stantial evidence standard on appeal. Consol. Edison, 305
 U.S. at 229.
      We also agree with the examiner’s and Board’s deter-
 mination that the dimethylacrylamide polymer meets the
 intrinsic viscosity limitation of the claim. Solenis identifies
 no errors in the examiner’s calculation using the MHS
 equation. Nor do we find error in his determination that,
 based on the MHS equation, intrinsic viscosity is propor-
 tional to molecular weight such that the intrinsic viscosity
 of the WO ’973 polymers with molecular weights preferably
 greater than 1 million would be expected to have higher
 intrinsic viscosities than 16.8 dl/g.
     The Board and examiner used a well-known equation
 to determine an inherent property—the intrinsic viscos-
 ity—of a polymer in the prior art. The inherency of a
 claimed material is not at issue in this analysis; it is the
 inherency of a property that is at issue, and substantial ev-
 idence shows that the polymer possesses that property. We
 discern no error in this analysis.
     Regarding claim 10, Solenis argues that EP ’120 does
 not inherently disclose branched polymers because the
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 SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS                   11



 disclosure does not specify whether branched or block co-
 polymers are formed. According to Solenis, because the EP
 ’120 polymers are not necessarily branched, the polymers
 do not necessarily have the claimed tan delta values. Sole-
 nis also argues that, since the EP ’120 polymers are not
 necessarily branched, the Board’s alternative conclusion
 that EP ’120 would have motivated a person skilled in the
 art to use a branched, water-soluble cationic polymer lacks
 substantial evidence.
     It is unclear that the Board relied on inherency to find
 polymers disclosed by EP ’120 are necessarily branched.
 The Board determined that it would have been obvious to
 use branched cationic polymers because EP ’120 discloses
 branched or block copolymers. EP ’120 describes a disper-
 sion polymerization reaction that yields a water-soluble
 polymer. The polymerization mechanism is unknown, and
 the inventors “assumed that a polymer having a specific
 molecular structure, such as a branched polymer or block
 copolymer, is produced.” EP ’120 at 4.
     The Board’s determination that “it would have been ob-
 vious to optimize the water soluble cationic polymer to se-
 lect a branched soluble polymer as taught by EP ’120
 because of the desire for a water soluble and easily dissolv-
 able cationic polymer” is supported by the record. Second
 Board Decision, 2018 WL 3456088, at *5. EP ’120 credits
 the structure of the generated polymer as a “primary factor
 of improving retention and/or drainage,” and therefore
 teaches that a branched polymer may be responsible for
 improvements to the papermaking process. EP ’120 at 6.
 It was thus reasonable for the Board to conclude that it
 would have been obvious for a skilled artisan to use
 branched copolymers based on EP ’120’s express disclosure,
 and the Board’s obviousness conclusion is supported by
 substantial evidence.
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 12                     SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS



                              B.
     After the first Board decision, Solenis requested reo-
 pening prosecution under 37 C.F.R. § 41.77(b)(l) and sub-
 mitted the Jehn-Rendu declaration. The request was
 granted for claim 10, which was subject to a new ground of
 rejection, but was denied for claim 13. Remand Order, No.
 2015-007695, slip op. at 3; J.A. 1975. Specifically, the
 Board entered a new ground of rejection based on its find-
 ing that a combination of WO ’973, EP ’120, and the ’188
 patent discloses branched polymers of a rheological oscilla-
 tion tan delta value of above 0.7.
     As a preliminary matter, in its request to reopen pros-
 ecution, Solenis argued the issue of intrinsic viscosity with
 respect to claim 13 alone. See J.A. 1946–49. Solenis’s ar-
 guments regarding claim 10 address only whether EP ’120
 and the ’188 patent disclose a branched water-soluble pol-
 ymer with the claimed rheological oscillation value. J.A.
 1940–43. The examiner considered the declaration and the
 request in his determination on remand. J.A. 1989–90.
 Thus, it is not surprising that the examiner’s analysis on
 remand addresses the Jehn-Rendu declaration only as it
 relates to the claimed tan delta value of claim 10.
      On remand to the examiner after the Board issues a
 new ground of rejection, 37 C.F.R. § 41.77(d) tasks the ex-
 aminer to consider whether new evidence not previously of
 record overcomes the new ground of rejection in the Board’s
 decision. The Manual of Patent Examining Procedure
 (“MPEP”) § 2682 (9th ed., rev. Jan. 2018), provides similar
 guidance, explaining that “examiner will not comment on
 any entered arguments or comments that are not limited
 to the new ground(s) of rejection issued in the Board’s de-
 cision (e.g., arguments or comments that addressed a
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 SOLENIS TECHNOLOGIES, L.P.   v. SNF SAS                     13



 rejection affirmed in the Board’s decision).” 3 The examiner
 clearly followed the applicable regulations and guidance in
 considering the Jehn-Rendu declaration for the limited
 purpose of the new ground of rejection. Solenis has failed
 to identify any procedural error warranting a remand.
                         CONCLUSION
      We have considered Solenis’s remaining arguments but
 find them unpersuasive. Accordingly, the decision of the
 Board finding claims 2–55 of the ’902 patent unpatentable
 is affirmed.
                         AFFIRMED




     3    “While the MPEP does not have the force of law, it
 is entitled to judicial notice as an official interpretation of
 statutes or regulations as long as it is not in conflict there-
 with.” Molins PLC v. Textron, Inc., 48 F.3d 1172, 1180 n.10
 (Fed. Cir. 1995) (citing Litton Sys., Inc. v. Whirlpool Corp.,
 728 F.2d 1423, 1439 (Fed. Cir. 1984)).
