`571-272-7822 Date: December 19, 2017
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
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`GENERAL ELECTRIC COMPANY,
`Petitioner,
`
`v.
`
`UNITED TECHNOLOGIES CORPORATION,
`Patent Owner.
`____________
`
`Case IPR2016-01289
`Patent 7,060,360 B2
`____________
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`
`
`Before GRACE KARAFFA OBERMANN, CHRISOPHER M. KAISER,
`and MICHELLE N. ANKENBRAND, Administrative Patent Judges.
`
`OBERMANN, Administrative Patent Judge.
`
`
`FINAL WRITTEN DECISION
`Finding Claims 1–14 Unpatentable
`35 U.S.C. § 318 and 37 C.F.R. § 42.73
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`I. INTRODUCTION
`This is a Final Written Decision in an inter partes review of claims 1–
`14 of U.S. Patent No. 7,060,360 B2 (Ex. 1001, “the ’360 patent”). We
`instituted trial under 35 U.S.C. § 314 based on challenges asserted in the
`Petition (Paper 1 (“Pet.”)). Paper 7 (Institution Decision (“Dec.”)). Patent
`Owner filed a Response under 37 C.F.R. § 42.120. Paper 12 (“Resp.”).
`Petitioner filed a Reply to Patent Owner’s Response. Paper 16 (“Reply”).
`Patent Owner does not seek to amend any challenged claim under
`37 C.F.R. § 42.121. Although Petitioner filed objections to the admissibility
`of evidence served with Patent Owner’s Response (Paper 13), neither party
`filed a motion to exclude evidence.
`An oral hearing was conducted on September 18, 2017, and a
`transcript was made of record. Paper 24, (“Tr.”)). After the hearing, with
`Board pre-authorization (Paper 20), Petitioner filed a supplemental brief
`(Paper 21) and Patent Owner filed a responsive supplemental brief
`(Paper 22). For reasons that follow, we conclude that Petitioner shows by a
`preponderance of evidence that claims 1–14 are unpatentable under 35
`U.S.C. § 103.
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`A. Related Matters
`The parties do not identify any related district court actions or
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`administrative proceedings. Pet. 1; Paper 4, 2.
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`B. The ’360 Patent
`The ’360 patent is titled “Bond Coat for Silicon Based Substrates.”
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`Ex. 1001, Title. The ’360 patent relates to an environmental barrier coating
`for protecting a silicon-containing substrate, such as combustor and turbine
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`sections of gas turbine engines. Id. at 1:7–18. Specifically, the coating
`protects the substrate from the adverse effects of oxidation in high
`temperature, aqueous environments, thereby increasing the service life of the
`components. Id. That coating comprises an alkaline earth aluminosilicate
`based on barium and strontium (also known as “BSAS”), or yttrium silicate.
`Id. at 1:22–24, claim 1; Pet. 9. A “bond layer” is located between the
`substrate and the BSAS coating. Id. at 1:19–47; claim 1.
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`The ’360 patent discloses that the BSAS coating was known in the
`prior art. Id. at 1:22–25. The specification also identifies, as prior art, a
`bond layer (located between the BSAS coating and the substrate) comprising
`“a dense continuous layer of silicon metal.” Id. at 21–22; Fig. 1. The
`inventors claim to have discovered that, by using a bond layer that includes
`an alloy comprising a refractory metal disilicide/silicon eutectic, instead of
`“a simple phase silicon metal bond coat,” the fracture toughness of the bond
`coat is increased, resulting in “more resistance to crack propagation.” Id.
`at 1:50–2:3; see claim 1 (specifying a bond layer including an alloy
`comprising a refractory metal disilicide/silicon eutectic).
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`C. Illustrative Claim
`Claim 1, reproduced below, is illustrative of the subject matter:
`1. An article comprising a silicon based substrate, at least one
`environmental barrier layer selected from the group consisting
`essentially of an alkaline earth aluminosilicate based on barium and
`strontium, and yttrium silicate, and a bond layer between the substrate
`and the environmental barrier layer, the bond layer comprises an alloy
`comprising a refractory metal disilicide/silicon eutectic.
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`Ex. 1001, 2:55–62.
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`D. Asserted Prior Art and Other Evidence
`The Petition asserts the following prior art references:
`1. Valentina Sergeevna Terentieva, et al., U.S. Patent
`No. 5,677,060, issued Oct. 14, 1997 (Ex. 1005, “Terentieva”);
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`2. Harry Edwin Eaton, Jr., et al., U.S. Patent No. 6,387,456 B1,
`issued May 14, 2002 (Ex. 1006, “Eaton”);
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`3. J.D. Webster, et al., Oxidation Protection Coatings
`for C/SiC Based on Yttrium Silicate, 18 J. EUR. CERAM. SOC.
`2345–2350 (1998) (Ex. 1025, “Webster”);
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`4. Yoshikazu Suzuki, et al., Improvement in Mechanical Properties of
`Powder-Processed MoSi2 by the Addition of Sc2O3 and Y2O3, 18(12) J.
`AM. CERAM. SOC. 3141–3149 (Dec. 1998) (Ex. 1024, “Suzuki”).
`The Petition is supported by the Declaration of Dr. Andreas M.
`Glaeser. Ex. 1003. Patent Owner’s Response is supported by the
`Declaration of Dr. David R. Clarke (Ex. 2001) and the Supplemental
`Declaration of Dr. Clarke (Ex. 2013).
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`E. The Asserted Grounds of Unpatentability
`Petitioner challenges the patentability of claims 1–14 of the ’360
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`patent on the following grounds:
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`Claims
`1–14
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`1–14
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`Basis
`§ 103
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`§ 103
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`References
`Terentieva and Eaton
`Terentieva, Webster, Suzuki,
`and Allegedly Admitted Prior Art
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`II. ANALYSIS
`Under 35 U.S.C. § 103, subject matter is unpatentable
`if the differences between the subject matter sought to be patented and
`the prior art are such that the subject matter as a whole would have
`been obvious at the time the invention was made to a person having
`ordinary skill in the art to which said subject matter pertains.
`The Supreme Court explains that, to determine obviousness,
`[o]ften, it will be necessary for a court to look to interrelated teachings
`of multiple patents; the effects of demands known to the design
`community or present in the marketplace; and the background
`knowledge possessed by a person having ordinary skill in the art, all
`in order to determine whether there was an apparent reason to
`combine the known elements in the fashion claimed by the patent at
`issue. To facilitate review, this analysis should be made explicit. . . .
`As our precedents make clear, however, the analysis need not seek out
`precise teachings directed to the specific subject matter of the
`challenged claim, for a court can take account of the inferences and
`creative steps that a person of ordinary skill in the art would employ.
`KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007). We analyze the
`evidence presented by Petitioner and Patent Owner in light of the Supreme
`Court’s guidance.
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`A. Level of Ordinary Skill in the Art
`We consider patentability in view of the understanding of a person of
`ordinary skill in the art. The prior art in this case itself is sufficient to
`demonstrate the level of ordinary skill in the art at the time of the invention.
`See Okajima v. Bourdeau, 261 F.3d 1350, 1355 (Fed. Cir. 2001) (prior art
`itself can reflect appropriate level of ordinary skill in the art). Further, based
`on the record developed during trial, we find that Petitioner’s witness,
`Dr. Glaeser, and Patent Owner’s witness, Dr. Clarke, both are qualified to
`opine from the perspective of an ordinary artisan at the time of the invention.
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`Ex. 1003 ¶¶ 5–12 (Dr. Glaeser’s statement of qualifications and experience);
`Ex. 1004 (Dr. Glaeser’s curriculum vitae); Ex. 2001 ¶¶ 3–7 (Dr. Clarke’s
`statement of qualifications and experience); Ex. 2005 (Dr. Clarke’s
`curriculum vitae).
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`B. Claim Interpretation
`The Board interprets claims in an unexpired patent using the “broadest
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`reasonable construction in light of the specification of the patent.” 37 C.F.R.
`§ 42.100(b); Cuozzo Speed Techs., LLC v. Lee, 136 S. Ct. 2131, 2144–46
`(2016). Under that standard, claim terms are given their ordinary and
`customary meaning in view of the specification, as understood by one of
`ordinary skill in the art at the time of the invention. In re Translogic Tech.,
`Inc., 504 F.3d 1249, 1257 (Fed. Cir. 2007).
`The parties advance differing interpretations of the term “bond layer”
`in claim 1. Ex. 1001, 2:60–62. We previously provided a preliminary claim
`construction “[f]or the sole purpose of reaching our decision to institute
`trial.” We expressly placed both parties on notice that “[a]ny final decision
`will include a final claim construction based on the full trial record,” giving
`both an ample opportunity to develop this issue further. Paper 7, 9.
`In Petitioner’s view, the term “bond layer” means “any layer located
`between at least two other layers or between the substrate and another
`layer.” Pet. 17 (citing Ex. 1003 ¶ 43) (testimony of Dr. Glaeser). For
`support, Petitioner directs us to intrinsic evidence, including a disclosure in
`the ’360 patent specification, which describes the “bond layer” in terms of
`its location with respect to the substrate or an intermediate layer. Id. at 17–
`18 (citing Ex. 1001, 2:13–17, Figs. 1a, 1b). Petitioner also advances a
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`statement made by the Examiner, during patent prosecution, that “when an
`outer layer is present, an intermediate layer existing between the outer layer
`and underlying substrate is ‘considered to effectively function as a bond
`layer.’” Id. at 18 (citing Ex. 1002, 32).
`Patent Owner disagrees, arguing that the word “bond” within the
`phrase “bond layer” conveys an additional, functional limitation that
`requires “a layer of material designed to adhere another layer to a substrate.”
`Resp. 40–44. For support, Patent Owner relies, with one exception, entirely
`on extrinsic evidence. See id. (relying on extrinsic evidence, including
`Dr. Clarke’s testimony, an extrinsic patent, a textbook, a dictionary
`definition, as well as other extrinsic publications) (citations omitted); see
`Ex. 2001 ¶ 71 (citing Ex. 2002, 311; Ex. 1013, Abstract), ¶ 74 (citing
`Ex. 2004, 130). That one exception is a disclosure in the specification that,
`according to Patent Owner, distinguishes a “bond layer” from an
`“intermediate layer” based on an “adherent function.” Resp. 42–43.
`Specifically, Patent Owner directs us to the following disclosure in
`the ’360 patent specification as evidence that the “bond layer” of claim 1
`must be “specifically designed to adhere” another layer to a substrate (id.
`at 40): “[A] silicon oxide intermediate layer or other intermediate layer may
`be provided between the bond layer and the silicon base substrate.”
`Resp. 43 (quoting Ex. 1001, 2:14–16) (emphasis omitted). That disclosure
`comports with “the permissive ‘comprising’ language [of] claim 1, which
`does not preclude an intermediate layer between the bond layer and the
`substrate.” Reply 20; Ex. 1001, 2:56 (claim 1).
`We discern nothing in that disclosure that persuasively demonstrates
`an intention to distinguish the layers based on an “adherent function.”
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`Resp. 43; see Ex. 1001, 2:14–16 (distinguishing the “bond layer” from an
`“intermediate layer” in terms of their relative locations within the article).
`The specification distinguishes the “bond layer” from the “intermediate
`layer” based on their relative locations within the article and their material
`compositions. See Ex. 1001, 2:14–16 (describing an intermediate layer in
`terms of its material composition, namely, “a silicon oxide intermediate
`layer”); id. at 2:60–62 (describing the “the bond layer” in terms of its
`material composition, namely, “an alloy comprising a refractory metal
`disilicide/silicon eutectic”).
`The best evidence on point (the claim language and written
`description) defines the “bond layer” in terms of its location (“between the
`substrate and the environmental barrier layer” or over “a silicon oxide
`intermediate layer or other intermediate layer” applied to the substrate) and
`material composition (“an alloy comprising a refractory metal
`disilicide/silicon eutectic”). Ex. 1001, 1:19–29, 51–54, 2:12–17, 25–43, 54,
`60–62. Accordingly, we determine that the inventors did not define the
`“bond layer” solely in terms of its location within the article. The “bond
`layer” further is defined by the material of which it is composed. Id. at
`2:25–27, 54, 60–62 (claim 1); Resp. 41 (Patent Owner, correctly arguing that
`“a bond layer is not simply a layer located between two other layers”).
`To the extent, however, that the word “bond” implies an additional
`limitation, pertaining to a quality or degree of adherence, we find that the
`claim language and written description suggest no feature (other than those
`imposed on location and material composition) that is required in order to
`ensure a bond adequate for use in the invention. On that critical point,
`the ’360 patent consistently describes the “bond layer” by its relative
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`location within the article and its material composition. Ex. 1001, 1:19–29,
`51–54, 2:12–17, 25–43, 54, 60–62. The ’360 patent is devoid of disclosure
`otherwise describing a characteristic of adherence. See generally Ex. 1001.
`The absence of disclosure relating to that characteristic suggests to us
`that the inventors did not use the word “bond” in claim 1 to convey an
`additional, functional limitation met only by some undisclosed degree or
`quality of adherence. Stated somewhat differently, we read the ’360 patent
`to inform that a layer that meets the requirements of location and material
`composition is a “bond layer” within the embrace of claim 1. In so holding,
`we are not “reading the word ‘bond’ out of the claim.” Resp. 44. We are
`assigning it the broadest reasonable interpretation that is consistent with the
`specification.
`On this record, we conclude that the “bond layer” of claim 1 is “any
`layer located between at least two other layers or between the substrate and
`another layer” (Pet. 17, 18; Ex. 1001, 2:13–17, 59–61) and which
`“comprises an alloy comprising a refractory metal disilicide/silicon
`eutectic.”1 Ex. 1001, 2:25–43, 61–62. No other claim term requires express
`construction. See Wellman, Inc. v. Eastman Chem. Co., 642 F.3d 1355,
`1361 (Fed. Cir. 2011) (“[C]laim terms need only be construed ‘to the extent
`necessary to resolve the controversy.’”) (quoting Vivid Techs., Inc. v. Am.
`Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999)).
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`1 The phrase that identifies the material composition of the “bond layer”
`appears expressly in claim 1. Ex. 1001, 2:61–62.
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`C. Prosecution History of the ’360 Patent
`The prosecution history provides useful information relating to the
`extent to which the Examiner considered Terentieva as relevant to the
`patentability of the claimed subject matter, and how the applicants overcame
`by claim amendment the Examiner’s rejections based on anticipation by
`Terentieva. We, thus, provide a brief summary of that history in this section.
`During patent prosecution, the applicants amended original claim 1 in
`response to a rejection based on anticipation by Terentieva. That original
`claim was directed to “[a]n article comprising a silicon based substrate and a
`bond layer” in which “the bond layer comprises an alloy comprising a
`refractory metal disilicide/silicon eutectic.” Ex. 1002, 66.2 The prosecution
`history suggests that the Examiner recognized that Terentieva discloses a
`layer with the requisite material composition—a refractory metal
`disilicide/silicon eutectic—located on a silicon-based substrate. Id. at 45–
`48, 66.
`In response to that rejection, the applicants amended the claim to
`require “at least one barrier layer, and a bond layer between the substrate
`and the barrier layer, the bond layer comprises an alloy comprising a
`refractory metal disilicide/silicon eutectic.” Id. at 37. The Examiner once
`again rejected the claim as anticipated by Terentieva. Id. at 29–33. In other
`words, the limitation on the location of the bond layer within the article was
`not enough, in the Examiner’s view, to distinguish the claimed subject
`matter from Terentieva’s disclosed article.
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`2 Exhibit 1002 is the prosecution history of the ’360 patent. We cite to the
`page numbers that Petitioner added to the bottom of the exhibit.
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`The applicants again amended claim 1. They added a limitation
`requiring “at least one environmental barrier layer selected from the group
`consisting essentially of an alkaline earth aluminosilicate based on barium
`and strontium, and yttrium silicate.” Ex. 1002, 21. The applicants
`maintained the language of the original claim 1, specifying the material of
`which the bond layer must be made, as well as the language added in the
`first amendment specifying the location of the bond layer within the article.
`Id. The prosecution history shows that this amendment was sufficient to
`distinguish the claimed invention from Terentieva—because the Examiner
`allowed the claim to issue. Id. at 12–15, 24. In other words, after the
`applicants specified the material composition of the environmental barrier
`layer, claim 1 was allowed. As explained below, Eaton discloses an
`environmental barrier layer that meets the compositional requirements of
`claim 1—but Eaton was not before the Examiner.
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`D. Challenge Based on Obviousness over Terentieva and Eaton
`Petitioner challenges the patentability of claims 1–14 on the ground
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`that the subject matter would have been obvious at the time of the invention
`over the combined disclosures of Terentieva and Eaton. We first address
`claim 1, the only independent claim, and then turn to dependent claims 2–14.
`(1) Independent Claim 1
`As explained above, Terentieva was before the Examiner during
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`prosecution and was a focus of that proceeding. Pet. 22–23 (citing Ex. 1002,
`29–33, 45–48). Like the Examiner, we find that Terentieva discloses a
`silicon-containing substrate coated with a refractory metal disilicide/silicon
`eutectic layer, which meets the compositional requirements of the “bond
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`layer” specified by claim 1. Ex. 1002, 31–32, 47 (Examiner, finding that
`Terentieva discloses a silicon-containing substrate coated with a refractory
`disilicide/silicon eutectic layer); see Ex. 1005, 1:14–18, 4:1–4 (Terentieva,
`disclosing a silicon-containing substrate coated with a refractory metal
`disilicide/silicon eutectic layer); Pet. 22 (citing Ex. 1003 ¶¶ 69–80
`(Dr. Glaeser, explaining how Terentieva meets the limitations of claim 1);
`id. at 19–20, 22 (explaining why Terentieva’s healing layer satisfies the
`claim 1 limitation requiring a “refractory metal disilicide/silicon eutectic”).
`The nub of the dispute is whether one of ordinary skill in the art
`would have been led to apply Eaton’s BSAS layer over the eutectic coating
`described in Terentieva—a modification that results in an article that
`satisfies claim 1, including the limitations on the location and material
`composition of the bond layer. We find, based on a preponderance of the
`evidence, that an ordinary artisan would have been led to modify
`Terentieva’s article in that manner.
`Eaton, which was not before the Examiner, describes a prior art BSAS
`coating that meets the compositional requirements of the environmental
`barrier layer specified in claim 1. Eaton demonstrates that the BSAS coating
`was recognized in the prior art as useful for protecting silicon-containing
`components in high-temperature, aqueous environments. Pet. 20–21 (citing
`Ex. 1006, 1:60–63, 2:5–8, 10–14; 3:2–5; Ex. 1003 ¶ 63); see id. at 23–25
`(and citations to evidence therein) (showing that silica volatizes in water
`vapor, which causes rapid recession of silicon-based ceramics).
`The parties disagree about whether an ordinary artisan would have
`recognized the utility of applying Eaton’s BSAS layer over Terentieva’s
`eutectic layer to protect, not only a silicon-containing substrate, but also the
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`surface oxide film that forms on Terentieva’s eutectic. See Pet. 20 (citing
`Ex. 1003 ¶ 61 (Dr. Glaeser, explaining how Terentieva’s “surface oxide
`film” is formed); Ex. 1005, 3:7–12 (Terentieva’s disclosure of silica oxide,
`silicon carbide, and silicon nitride films that are formed on the surface of the
`eutectic)). On that point, Petitioner’s witness, Dr. Glaeser, opines that the
`subject matter of claim 1 represents no more than the use of a known
`material (the prior art BSAS coating) in a known way (as an environmental
`barrier layer) to achieve a predictable result (protecting a silicon-containing
`material; that is, the surface oxide film that forms on Terentieva’s eutectic
`layer). Ex. 1003 ¶¶ 71–77; Pet. 26–27.
`Dr. Glaeser’s opinion is supported by objective evidence, including
`information that, by the early 1990s, the focus of research and development
`in the field of environmental barrier layers had “shifted toward the
`protection from water vapor attack.” Ex. 1011, Abstract. That evidence
`supports a finding that an ordinary artisan would have understood that “an
`environmental overlay coating was necessary when protection from water
`vapor was needed.” Pet. 24 (quoting Ex. 1011, 3); see id. at 7–8 (bridging
`sentence), 24 (quoting Ex. 1014, 22) (silicon-based ceramics “suffer from
`rapid surface recession in combustion environments, due to the volatilization
`of the silica scale via reaction with water vapor”); Reply 7–8 (and evidence
`cited therein). Significantly, Terentieva discloses a surface oxide film that is
`vulnerable to water vapor attack. Ex. 1005, 3:5–7. A preponderance of
`evidence establishes that an ordinary artisan would have understood that the
`surface oxide film disclosed in Terentieva is vulnerable to the same attack
`and degradation by water vapor as described in the prior art, including
`Eaton. Pet. 7–8, 23–25 (and evidence cited therein).
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`Further, by the time of the invention of the ’360 patent, “one of
`ordinary skill in the art would have been aware of the degradation of silica in
`high temperature, aqueous environments and would have been motivated to
`maintain the integrity and longevity of Terentieva’s silicon-containing
`components.” Pet. 27 (and evidence cited therein, including Dr. Glaeser’s
`well-supported declaration testimony (Ex. 1003 ¶¶ 24–26, 72–77)). We
`credit Dr. Glaeser’s opinion, which is supported by objective proof, that “a
`person of ordinary skill in the art would have known that an additional
`protective layer was necessary to maintain the integrity of Terentieva’s
`refractory metal disilicide coating” in an environment conducive to water
`vapor attack. Ex. 1003 ¶ 73; see generally Ex. 1006 (Eaton, discussing a
`need for a protective environmental barrier layer to inhibit the degradation of
`a silicon containing substrate); see also Pet. 24–25 (citing Ex. 1011, 3
`(“Therefore, an environmental overlay coating was necessary when
`protection from water vapor was needed.”); Ex. 1014, 22 (“As the
`commercialization of Si-based ceramic components in gas turbines is on the
`horizon, a major emphasis is placed on EBCs [environmental barrier
`coatings] for two reasons. First, they are [an] absolute necessity for the
`protection of Si-based ceramics from water vapor.”)). Accordingly, based
`on a preponderance of evidence, we hold that the same combustion
`environment considerations that applied to Si-based ceramics would apply
`also to Terentieva’s SiO2-forming alloys, such as molybdenum disilicide
`(MoSi2). Pet. 8 (citing Ex. 1019 ¶ 1), 28 (citing Ex. 1003 ¶¶ 45–51, 54–57).
`We are not persuaded by Patent Owner’s counterargument that the
`addition of Eaton’s BSAS layer “would hinder or altogether eliminate” the
`healing function of Terentieva’s surface oxide film-forming eutectic.
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`Resp. 22.3 Patent Owner focuses on several characteristics of Terentieva’s
`surface oxide film-forming eutectic. Resp. 15–31. For example, Patent
`Owner argues that an ordinary artisan would have recognized that applying
`Eaton’s BSAS layer over Terentieva’s eutectic would hinder or destroy the
`healing functionality of the surface oxide film by decreasing its temperature
`(and, thereby, producing a deleterious increase in its viscosity). Id. at 22–27.
`That argument relies primarily on Dr. Clarke’s opinion testimony that
`adding Eaton’s BSAS layer over Terentieva’s eutectic layer would produce a
`temperature drop, which would disadvantageously increase the viscosity of
`Terentieva’s surface oxide film. Id. (citing Ex. 2013 ¶¶ 22–26, 28–32, 41–
`48). Even if we accept that testimony, we nonetheless are persuaded that a
`person, exercising no more than ordinary skill in the art, would have been
`equipped to address that problem. Dr. Clarke acknowledged during cross-
`examination that he based his opinion on an assumption that an ordinary
`artisan would have kept constant the gas flow temperature, even after the
`addition of a BSAS protective coating. Reply 10–11 (citing Ex. 1031,
`51:10–53:6). In other words, Dr. Clarke did not consider the possibility that
`an ordinary artisan would have addressed a disadvantageous temperature
`drop simply by increasing the gas flow temperature. See id.; Ex. 1031,
`52:5–53:6.
`A preponderance of evidence persuades us that this solution—
`increasing the gas flow temperature to address a temperature drop after
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`3 Patent Owner sometimes refers to Terentieva’s surface oxide film-forming
`eutectic as a “protective coating.” See, e.g., Resp. 22, 24. That should not to
`be confused with the protective coating of Eaton, which is the BSAS layer
`applied over Terentieva’s article in the proposed combination.
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`applying a protective coating—was known in the art. On that point,
`Dr. Clarke’s own prior work recognized that the use of similar protective
`coatings would advantageously “allow[] the turbine designer to increase the
`gas temperature and thereby the engine efficiency, without increasing the
`surface temperature of the alloy.” Reply 3 (citing Ex. 1010, 1).
`In forming his somewhat incongruous opinion for purposes of this
`proceeding, Dr. Clarke focuses on the effect of a temperature drop, across an
`environmental barrier layer, on the viscosity of a surface oxide film
`subjected to a temperature of only 1300˚C. Selecting the thicker of two
`coatings disclosed in Eaton, Dr. Clarke makes no attempt to explain why he
`ignores the much higher surface temperatures discussed in Terentieva’s
`examples. Reply 12–13 (citing Ex. 2013 ¶ 26, 32, 48); Ex. 1031, 54:18–
`54:4. We observe, however, that Dr. Clarke selects the lower end of the
`temperature range reported in Terentieva as “the melting point of the
`eutectic.” Ex. 1005, 4:35–38.
`Dr. Clarke does not explain adequately how or why his calculations,
`based on heating to a surface temperature of only 1300˚C, would apply to
`the viscosity of the surface oxide film in the modified article of Terentieva.
`On that point, Terentieva exposes the surface oxide film to significantly
`higher temperatures and thermal cycling. See Reply 13 (citing Ex. 1005,
`6:7–20); Ex. 1005, 5:63–6:20 (Terentieva’s Example 1, heating the sample
`to 1775˚C after 50 thermal cycles); Ex. 2013 ¶¶ 26, 32, 48) (Dr. Clarke’s
`declaration). Elsewhere, Patent Owner acknowledges that an ordinary
`artisan would have taken into consideration “the principles governing how
`coatings function in high-temperature operating conditions” under “cyclic
`temperature” changes. Resp. 8.
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`Further, Dr. Clarke does not sufficiently address Terentieva’s express
`disclosure that one may apply an additional protective coating over the
`surface oxide film-forming eutectic. Ex. 1005, 3:7–12 (contemplating the
`optional addition of a protective layer “comprising at least one oxide such as
`a layer of silica, alumina, or zirconia glass, or a layer of a non-oxide ceramic
`such as silicon carbide” “or silicon nitride”). Dr. Clarke agreed during
`cross-examination that the optional outer refractory layer disclosed in
`Terentieva, like “any coating,” would lower the temperature experienced by
`the layer below. Reply 12 (citing Ex. 1031, 55:20–56:1). This evidence
`suggests that lowered temperature was not a concern for Terentieva.
`Petitioner identifies additional persuasive evidence tending to establish that
`an optional protective coating (such as Eaton’s BSAS layer) would not have
`hindered, much less destroyed, the healing function of Terentieva’s eutectic.
`See id. at 10–13 (and evidence cited therein).
`Somewhat relatedly, Patent Owner argues that the application of an
`additional protective coating (such as Eaton’s BSAS layer) over Terentieva’s
`eutectic phase would negate a key design feature that depends on exposing
`the surface oxide film and eutectic “to high velocity gas flows.” Reply 30–
`31. Here again, however, Patent Owner ignores Terentieva’s express
`instruction that one may apply an additional protective coating successfully
`over the surface oxide film-forming eutectic layer. Ex. 1005, 3:7–12.
`Patent Owner further argues that an ordinary artisan would have
`recognized that applying Eaton’s BSAS coating over Terentieva’s eutectic
`would result in a “[r]edundant [f]unctionality” because both coatings protect
`against oxidation. Resp. 27–31. On that point, based on a preponderance of
`evidence, we find that Eaton’s BSAS coating is not duplicative of
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`Terentieva’s coating. Pet. 17–19, 23–30; see Reply 14 (citing Ex. 2014,
`31:15–32:2 (distinguishing between corrosion (steam attack) and oxidation).
`Although acknowledging that Terentieva’s eutectic phase provides oxidation
`protection, Petitioner directs us to persuasive evidence that Eaton’s BSAS
`coating would have been understood to provide an additional, non-
`duplicative benefit. Specifically, unlike Terentieva’s surface oxide film-
`forming eutectic, the BSAS coating would have been recognized as useful to
`protect against “the corrosive attack of steam on silica.” Reply 14 (citing
`Ex. 2014, 73:18–74:3). On this record, a preponderance of evidence
`supports a finding that an ordinary artisan would have recognized a “benefit”
`in “maintaining both layers” and, therefore, would have been led to apply
`Eaton’s BSAS layer over Terentieva’s article. Resp. 28.
`In addition, Patent Owner contends that “an increase in the thickness
`of a multilayer coating can give rise to increases in residual stresses in the
`coating and can ultimately lead to mechanical failures.” Resp. 28, 29 (citing
`Ex. 1001, 1:44–47 (the ’360 patent); Ex. 2001 ¶¶ 58–61, 100–101
`(Dr. Clarke’s opinion) (other citations omitted). In Patent Owner’s view, the
`Petition is deficient for failing to address the impact of increased thickness
`resulting from applying Eaton’s BSAS layer over Terentieva’s eutectic
`layer. Id. at 29–30. As Petitioner explains, however, “[t]his argument
`ignores entirely Terentieva’s optional” protective coating, “which will also
`necessarily increase the overall thickness.” Reply 16; see Ex. 1005, 3:7–12
`(Terentieva, describing the use of an optional, additional protective coating).
`Further, Terentieva elsewhere suggests that the “coating thickness is
`simply a design consideration rather than a deterrent to adding an [additional
`layer] in the first place.” Reply 16 (citing Ex. 1005, 5:7–8 (“[t]he thickness
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`of the deposited layer is selected as a function of the thickness desired for
`the protective coating”). We credit the disclosures, within the four corners
`of Terentieva (specifically, Ex. 1005, 3:7–12, 5:7–8), over Dr. Clarke’s
`opinion testimony that one would have been “led away” from applying
`Eaton’s BSAS layer over Terentieva’s coating based on concerns about an
`increase in thickness. Resp. 2–3 (citing Dr. Clarke’s declaration (Ex. 2001
`¶¶ 1