Trials@uspto.gov
`571-272-7822
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`Paper 48
`Date: May 16, 2022
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`UNITED STATES PATENT AND TRADEMARK OFFICE
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`________________________
`
`SAMSUNG ELECTRONICS CO., LTD. and
`SAMSUNG ELECTRONICS AMERICA, INC.,
`Petitioner,
`v.
`NANOCO TECHNOLOGIES LTD.,
`Patent Owner.
`
`IPR2021-00185
`Patent 7,867,557 B2
`
`
`Before ERICA A. FRANKLIN, GRACE KARAFFA OBERMANN, and
`CHRISTOPHER M. KAISER, Administrative Patent Judges.
`
`OBERMANN, Administrative Patent Judge.
`
`
`
`
`JUDGMENT
`Final Written Decision
`Determining No Challenged Claims Unpatentable
`35 U.S.C. § 318(a)
`
`

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`IPR2021-00185
`Patent 7,867,557 B2
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`I. INTRODUCTION
`This is a Final Written Decision in an inter partes review of claims 1–
`
`6, 16, and 17 of U.S. Patent No. 7,867,557 B2 (Ex. 1001, “the ’557 patent”).
`We have jurisdiction under 35 U.S.C. § 6 and enter this Decision pursuant to
`35 U.S.C. § 318(a). For the reasons that follow, we determine that
`Petitioner1 does not establish by a preponderance of the evidence that any
`challenged claim is unpatentable.
`A. Procedural History
`Petitioner filed a Petition requesting review of the challenged claims.
`Paper 1 (“Pet.”). With the Petition, Petitioner filed the Declaration of Mark
`A. Green, Ph.D., in support of the challenges stated in the Petition. Ex. 1002.
`Patent Owner2 filed a Preliminary Response to the Petition (Paper 12).
`Pursuant to our authorization, Petitioner filed a Reply (Paper 14) and Patent
`Owner filed a Sur-reply (Paper 15).
`Based on that preliminary record, we instituted an inter partes review
`of all challenged claims based on all grounds of unpatentability asserted in
`the Petition. Paper 17 (“Dec.”). The following table sets forth the grounds.3
`
`
`
`1 “Petitioner” refers collectively to Samsung Electronics Co., Ltd. and
`Samsung Electronics America, Inc. See Paper 39, 1 (identification of
`Petitioner’s real parties-in-interest).
`2 “Patent Owner” refers to Nanoco Technologies Ltd. Paper 6, 1. See
`Paper 6, 1 (identification of Patent Owner’s real party-in-interest).
`3 The Leahy-Smith America Invents Act (“AIA”), Pub. L. No. 112-29, 125
`Stat. 284, 287–88 (2011), amended 35 U.S.C. § 103, effective March 16,
`2013. Because the ’557 patent application has an effective filing date prior to
`March 16, 2013, the pre-AIA version of § 103 applies.
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`IPR2021-00185
`Patent 7,867,557 B2
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`Claims Challenged
`
`35 U.S.C. §
`
`1–6, 16, 17
`
`1, 16, 17
`
`4–6
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`1, 4, 16, 17
`
`103(a)
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`103(a)
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`103(a)
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`103(a)
`
`References
`
`Banin,4 Braun5
`
`Zaban,6 Ptatschek,7 Braun
`
`Zaban, Ptatschek, Braun, Yu8
`
`Lucey,9 Ahrenkiel,10 Braun
`
`
`After institution of trial, Patent Owner filed a Response (Paper 26,11
`“Resp.”), along with the Declaration of Brandi Cossairt, Ph.D. (Ex. 2030),
`
`
`4 Banin et al., WO 03/097904 A1, published Nov. 27, 2003 (“Banin,”
`Ex. 1005).
`5 Braun et al., Variation of the Thickness and Number of Wells in the
`CdS/HgS/CdS Quantum Dot Quantum Well System, 105 J. PHYS. CHEM. A.
`5548–5551 (2001) (“Braun,” Ex. 1013).
`6 Zaban et al., Photosensitization of Nanoporous TiO2 Electrodes with InP
`Quantum Dots, 14 LANGMUIR 3153–3156 (1998) (“Zaban,” Ex. 1006).
`7 Ptatschek et al., Quantized Aggregation Phenomena in II-VI-
`Semiconductor Colloids, 102 PHYS. CHEM. 85–95 (1998) (“Ptatschek,”
`Ex. 1008).
`8 Yu et al., Heterogeneous Seeded Growth: A Potentially General Synthesis
`of Monodisperse Metallic Nanoparticles, 123 J. AM. CHEM. SOC. 9198–9199
`(2001) (“Yu,” Ex. 1010).
`9 Lucey et al., US 7,193,098 B1, issued Mar. 20, 2007 (“Lucey,” Ex. 1011).
`10 Ahrenkiel et al., Synthesis and Characterization of Colloidal InP
`Quantum Rods, 3 (6) NANO LETTERS 833–837 (2003) (“Ahrenkiel,”
`Ex. 1012).
`11 Patent Owner filed Paper 26 (unredacted Response) under seal and
`Paper 27 (redacted Response) in the public record. Thereafter, “the parties
`agreed that” the Response does “not contain confidential information and”
`does “not need to be sealed.” Paper 31, 1.
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`Petitioner filed a Reply (Paper 33, “Reply”), along with the Second
`Declaration of Dr. Green (Ex. 1093), and Patent Owner filed a Sur-reply
`(Paper 40, “Sur-reply”).12 The parties presented oral arguments during a
`hearing held by video on February 23, 2022.13 Paper 47 (“Tr.”).
`B. Related Matters
`The parties identify litigation involving the ’557 patent as a related
`
`matter: Nanoco Technologies Ltd. v. Samsung Electronics Co., Ltd.,
`No. 2:20-cv-00038 (E.D. Tex.) (“District Court case”). Pet. 68; Paper 6, 1.
`The parties also identify, as related matters, petitions for review filed
`in connection with four other patents asserted in the District Court case:
`IPR2021-00182 for U.S. Patent No. 9,680,068, IPR2021-00183 for U.S.
`Patent No. 7,588,828 (“IPR183”), IPR2021-00184 for U.S. Patent
`No. 7,803,423 (“IPR184”), and IPR2021-00186 for U.S. Patent
`No. 8,524,365. Pet. 68; Paper 6, 1–2. Concurrently with this Decision, we
`enter final written decisions in those administrative proceedings.
`
`C. The ’557 Patent (Ex. 1001)
`The ’557 patent relates to a method for producing nanoparticles
`having a core, a first layer, and a second layer. Ex. 1001, 3:24–29. Each
`comprises a semiconductor material, but the core material differs from that
`
`
`12 Based on their respective statements of qualifications and curricula vitae,
`which are not contested, we determine that both Dr. Green and Dr. Cossairt
`are qualified to provide opinions about the knowledge and understanding of
`a person of ordinary skill in the art at the time of the invention. Ex. 1002
`¶¶ 17–30; Ex. 1003; Ex. 2030 ¶¶ 5–21, Appendix A.
`13 A consolidated hearing was conducted in IPR2021-00182, IPR2021-
`00183, IPR2021-00184, this proceeding, and IPR2021-00186, however, the
`cases are not consolidated. See Paper 44 (Order, setting oral argument).
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`of the first layer, and the first layer material differs from that of the second
`layer. Id. at 3:29–32, 30:65–31:17.
`The written description states, “There has been substantial interest in
`the preparation and characterization of compound semiconductors” that
`include “particles with dimensions in the order of 2–100 [nanometers] (nm),
`often referred to as quantum dots and nanocrystals.” Id. at 1:16–19. That
`interest “mainly” may be “due to their size-tunable electronic, optical, and
`chemical properties and the need for the further miniaturization of both
`optical and electronic devices.” Id. at 1:21–23. The written description
`further indicates that such nanoparticles may be useful in a “range” of
`“commercial applications,” including “biological labelling, solar cells,
`catalysts, biological imaging, [and] light-emitting diodes.” Id. at 1:24–27.
`The claimed method includes a step of “effecting conversion of a
`nanoparticle core precursor composition to the material of the nanoparticle
`core, depositing said first layer on said core and depositing said second layer
`on said first layer.” Id. at 3:33–36; see id. at 30:65–31:17 (claim 1). The
`“core precursor composition,” in turn, includes “a first precursor species
`containing a first ion to be incorporated into the growing nanoparticle core.”
`Id. at 3:35–38. The core precursor composition also includes “a separate
`second precursor species containing a second ion to be incorporated into the
`growing nanoparticle core.” Id. at 3:38–40. The “conversion” is “effected in
`the presence of a molecular cluster compound” (“MCC”) “under conditions
`permitting seeding and growth of the nanoparticle core.” Id. at 3:40–43.
`The written description provides examples for preparing a
`nanoparticle core (id. at 15:60–17:57), a first layer (id. at 21:27–22:33), and
`a second layer (id. at 22:35–40). That description also provides examples for
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`preparing MCCs. Id. at 26:27–47. In addition, the ’557 patent describes a
`preferred “three-step process” whereby “cores are synthesized and isolated
`from a growth solution,” then a first layer “is grown onto the cores in a
`separate reaction and isolated once again.” Id. at 23:45–51. An outer layer
`“is grown onto the core-shell structure,” thereby producing, for example, a
`“quantum dot-quantum well.” Id. at 23:51–53. The description further
`discusses experimental conditions for producing an exemplary nanoparticle
`represented by the formula ZnS/CdSe/CdxZn1-xS. Id. at 26:11–30:22.
`
`D. Challenged Claims
`We reproduce below claim 1, which is the sole independent
`challenged claim and illustrates the subject matter of the invention.
` 1. A method for producing a nanoparticle comprised of a core
`comprising a core semiconductor material, a first layer
`comprising a first semiconductor material provided on said core
`and a second layer comprising a second semiconductor material
`provided on said first layer, said core semiconductor material
`being different to said first semiconductor material and said first
`semiconductor material being different
`to said second
`semiconductor material, the method comprising:
`effecting conversion of a nanoparticle core precursor
`composition to the material of the nanoparticle core;
`depositing said first layer on said core; and
`depositing said second layer on said first layer, said core
`precursor composition comprising a first precursor species
`containing a first ion to be incorporated into the growing
`nanoparticle core and a separate second precursor species
`containing a second ion to be incorporated into the growing
`nanoparticle core,
`said conversion being effected in the presence of a molecular
`cluster compound different from the nanoparticle core precursor
`composition.
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`Ex. 1001, 30:65–31:17. The other challenged claims inherit the above
`limitations through direct or indirect dependence on claim 1. See id.
`at 31:18–56 (claims 2–6), 32:37–54 (claims 16 and 17).
`
`II. ANALYSIS
`Our analysis is centered on explaining why we determine that
`
`Petitioner does not carry its burden of proving the unpatentability of claim 1
`based on any ground asserted in the Petition. Petitioner advances no
`information, in connection with any other challenged claim, that cures the
`deficiencies that we identify below in the context of claim 1. See Pet 33–38,
`45–51, 59–62. Accordingly, the challenges asserted in the Petition rise and
`fall with the sufficiency of Petitioner’s showing made as to claim 1, and our
`analysis of claim 1 applies with equal force to each challenged claim.
`A. Principles of Law
`To prevail in this proceeding, Petitioner must demonstrate by a
`preponderance of the evidence that the challenged claims are unpatentable.
`35 U.S.C. § 316(e); 37 C.F.R. § 42.1(d) (2019). “In an [inter partes review],
`the petitioner has the burden from the onset to show with particularity why
`the patent it challenges is unpatentable.” Harmonic Inc. v. Avid. Tech., Inc.,
`815 F.3d 1356, 1363 (Fed. Cir. 2016); see also 35 U.S.C. § 312(a)(3) (2012)
`(requiring inter partes review petitions to identify “with particularity . . . the
`evidence that supports the grounds for the challenge to each claim”). That
`burden of persuasion never shifts to Patent Owner. Dynamic Drinkware,
`LLC v. Nat’l Graphics, Inc., 800 F.3d 1375, 1378 (Fed. Cir. 2015); see also
`In re Magnum Oil Tools Int’l, Ltd., 829 F.3d 1364, 1375–78 (Fed. Cir. 2016)
`(discussing the burden of proof in inter partes review proceedings).
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`A claim is unpatentable for obviousness if, to one of ordinary skill in
`the pertinent art, “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.” 35 U.S.C. § 103(a)
`(2006); see also KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406 (2007).
`The question of obviousness is resolved on the basis of underlying
`factual determinations including the scope and content of the prior art, any
`differences between the claimed subject matter and the prior art, the level of
`ordinary skill in the art, and objective evidence of nonobviousness.14
`Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966). “An obviousness
`determination requires finding both ‘that a skilled artisan would have been
`motivated to combine the teachings of the prior art references to achieve the
`claimed invention, and that the skilled artisan would have had a reasonable
`expectation of success in doing so.’” CRFD Research, Inc. v. Matal, 876
`
`
`14 Although Patent Owner does not expressly argue that any objective
`evidence of nonobviousness undercuts Petitioner’s challenges in this case,
`Patent Owner does assert that Petitioner tried, without success, “to solve
`problems associated with producing cadmium-free quantum dots” and,
`further, that Petitioner’s “research lead” considered “developing cadmium-
`free quantum dot technology ‘to be quite a challenge.’” Resp. 9 (quoting
`Ex. 2005, 3). In addition, according to Patent Owner, Petitioner
`acknowledged that “the development of cadmium-free quantum dots was not
`as straightforward as optimizing existing synthesis methods.” Id. (citing
`Ex. 2006, 1316). To the extent Patent Owner asserts that these factual
`contentions are secondary indicia of non-obviousness, the contentions are
`not developed adequately. Id. In any event, even if we set aside those
`contentions, for reasons explained in our analysis of the challenges, we
`determine that Petitioner fails to show by a preponderance of the evidence
`that the prior art supports a finding of obviousness.
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`F.3d 1330, 1340 (Fed. Cir. 2017) (quoting Intelligent Bio-Sys., Inc. v.
`Illumina Cambridge Ltd., 821 F.3d 1359, 1367–68 (Fed. Cir. 2016)).
`We analyze Petitioner’s challenges according to the above-stated principles.
`B. Person of Ordinary Skill in the Art
`The level of skill in the art is a factual determination that provides a
`primary guarantee of objectivity in an obviousness analysis. Al-Site Corp. v.
`VSI Int’l Inc., 174 F.3d 1308, 1324 (Fed. Cir. 1999) (citing Graham v. John
`Deere Co., 383 U.S. 1, 17–18 (1966); Ryko Mfg. Co. v. Nu-Star, Inc., 950
`F.2d 714, 718 (Fed. Cir. 1991)). In Petitioner’s view, an ordinarily skilled
`artisan would have had “at least a Ph.D. in chemistry, physics, chemical
`engineering, material science, or equivalent technical degree or equivalent
`work experience, with knowledge regarding nanoparticles and methods of
`synthesizing them” and “[a]dditional education might supplement practical
`experience and vice-versa.” Pet. 22 (citing Ex. 1002 ¶ 76). Patent Owner
`does not address Petitioner’s view or propose a counter definition.
`We determine that the level of ordinary skill is reflected in the prior
`art of record. See Okajima v. Bourdeau, 261 F.3d 1350, 1355 (Fed. Cir.
`2001) (specific findings on the ordinary skill level are not required “where
`the prior art itself reflects an appropriate level and a need for testimony is
`not shown” (quoting Litton Indus. Prods., Inc. v. Solid State Sys. Corp., 755
`F.2d 158, 163 (Fed. Cir. 1985))). To the extent a more specific definition is
`required, we adopt Petitioner’s definition for purposes of this Decision,
`because that definition is unopposed and consistent with the disclosures of
`the asserted prior art references.
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`C. Claim Construction
`The Board applies the same claim construction standard that would be
`used to construe the claim in a civil action under 35 U.S.C. § 282(b).
`37 C.F.R. § 42.100(b) (2020). Under that standard, claim terms “are
`generally given their ordinary and customary meaning” as understood by a
`person of ordinary skill in the art at the time of the invention. Phillips v.
`AWH Corp., 415 F.3d 1303, 1312–13 (Fed. Cir. 2005) (en banc). “In
`determining the meaning of the disputed claim limitation, we look
`principally to the intrinsic evidence of record, examining the claim language
`itself, the written description, and the prosecution history, if in evidence.”
`DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 469 F.3d 1005, 1014
`(Fed. Cir. 2006) (citing Phillips, 415 F.3d at 1312–17). Extrinsic evidence is
`“less significant than the intrinsic record in determining ‘the legally
`operative meaning of claim language.’” Phillips, 415 F.3d at 1317.
`Petitioner asserts that:
`The ’557 patent does not define the phrase “molecular
`cluster compound.” Two other patents assigned to [Patent
`Owner] and with overlapping inventors both describe the term as
`“widely understood,” but U.S. Patent No. 7,803,423 [at issue in
`related IPR184] states that the term relates to “clusters of three
`or more metal or nonmetal atoms and their associated ligands,”
`while U.S. Patent No. 7,588,828 [at issue in related IPR183]
`states it is limited to “clusters of 3 or more metal atoms and their
`associated ligands.” Compare Ex. 1055, 5:3–12, with Ex. 1054,
`3:29–35. This issue need not be resolved, however, because the
`grounds relied on in this Petition disclose [molecular cluster
`compounds] with three or more metal atoms.
`Pet. 23 (footnotes omitted) (Petitioner’s emphasis). Petitioner states that,
`according to the written description of the invention, the molecular clusters
`are “of sufficiently well-defined chemical structure such that all molecules
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`of the cluster compound possess the same relative molecular mass.” Id. at 23
`n.6.
`
`Patent Owner responds that “the District Court construed the term
`‘molecular cluster compound’ to mean ‘clusters of three or more metal
`atoms and their associated ligands of sufficiently well-defined chemical
`structure such that all molecules of the cluster compound possess the same
`relative molecular formula.’” Resp. 28 (quoting Ex. 1091, 18). As Patent
`Owner points out, “The parties dispute whether ‘sameness’ is measured in
`terms of ‘molecular formula’ or ‘molecular mass’ of the cluster compound-–
`but this is a distinction without a difference for purposes of this IPR
`proceeding.” Id. at 29 n.2 (citing Pet. 22–23). On that point, Patent Owner
`observes, the District Court held that “the term ‘molecular formula’ as
`opposed to ‘molecular mass’ is most appropriate. By necessity, a compound
`with the same molecular formula will necessarily have the same molecular
`mass.” Id. (quoting Ex. 1091, 16). Petitioner does not contest that point
`effectively, if at all. See Reply 1 n.1 (Petitioner’s assertion that the
`challenged claims are unpatentable “under any possible construction”).
`Based on our consideration of the record as a whole, we agree with
`the District Court that the molecular cluster compound of the claimed
`invention must have “sufficiently well-defined chemical structure such that
`all molecules of the cluster compound possess the same relative molecular
`formula.” Ex. 1091, 18. To the extent that this or any other claim term
`requires further discussion, we provide it in our analysis of the challenges.
`No further express claim construction is necessary for purposes of this
`Decision. 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
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`necessary to resolve the controversy.’” (quoting Vivid Techs., Inc. v. Am.
`Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999))).
`
`D. Overview of the Asserted Prior Art References
`1. Banin
`Banin “relates to a method for synthesizing rod-shaped semiconductor
`nanocrystals, inter alia rod-shaped Group III-V semiconductor
`nanocrystals.” Ex. 1005, 2:2–4.15 Banin describes “introducing nanoparticles
`of a metal catalyst that serve as starting nanocrystals from which nanorods
`of inorganic semiconductors grow in solution while stopping the growth to
`obtain rods.” Id. at 7:3–6. Banin discloses that “[t]he metal catalyst can be
`made, for example, of a transition metal, e.g. Zn, Cd, Mn, etc., a Group IIIa
`metal, e.g. In, Ga, Al, alloys of such metals such as for example Au-In, or
`core/shell layered metal particle.” Id. at 7:9–11.
`We reproduce below Banin’s Figure 1.
`
`
`15 We refer to original page numbers in Exhibit 1005, not page numbers
`added by Petitioner.
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`Figure 1 illustrates the growth mechanism of InAs nanorods for Banin’s
`invention. Id. at 11:11–12. Banin describes, for example, that “InAs
`nanorods were synthesized via the reaction of tris(trimethylsilyl)arsenine
`((TMS)3As) and InCl3 in trioctylphosphine-oxide (TOPO), using metallic
`indium or gold as the catalyst.” Id. at 14:9–11. Metal catalyst M forms a
`starting nanocrystal from which a semiconductor nanorod grows, with the
`left end of the III-V semiconductor nanorod grown first and then moved
`away from the catalyst M during growth of the nanorod. Id. at 14:11–16.
`Banin also uses “small Au clusters (1.4 nm in mean diameter) instead
`of Au particles (2 nm in mean diameter)” and describes an experiment that
`uses “triphenylphosphine coated Au clusters with a diameter of 1.4 nm and
`the suggested formula Au101(PPh3)21Cl5” to prepare InAs rods. Id. at 21:12–
`17. Banin further discloses that its metal catalyst can be “Fe, Zn, Pd, Pt, Ni,
`Co, Mn, Ag, Cd or alloys and layered particles thereof.” Id. at claim 30.
`2. Zaban
`Zaban is a paper titled “Photosensitization of Nanoporous TiO2
`
`Electrodes with InP Quantum Dots.” Ex. 1006, 3153. Zaban describes a
`method for synthesizing quantum dots from precursors in a solution that
`includes zinc acetate as a dopant. Id. at 3154; see Pet. 38; Reply 20
`(acknowledging that Zaban relates to a “Zn-doped” nanoparticle synthesis).
`In Zaban’s synthetic method, zinc acetate is employed as a dopant “in a
`ratio” to produced doped quantum dots of indium phosphide that “contain on
`average one Zn2+ ion per particle.” Ex. 1006, 3154.
`3. Ptatschek
`Ptatschek is a paper titled “Quantized Aggregation Phenomena in II-
`
`VI Semiconductor Colloids.” Ex. 1008, 85. The focus of the paper is “the
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`sol-gel chemistry of metal oxides” and, in particular, “metal ethoxy-acetate
`derived synthesis of II-VI chalcogenide quantum dots.” Id.
`Ptatschek describes “semiconductor quantum dot solutions for coating
`applications” made using “cluster-like cadmium and zinc ethoxy-acetates.”
`Id. Ptatschek describes “[a] new route . . . for the preparation of
`concentrated” group “II–VI quantum dot coating solutions,” in which “initial
`nucleation in organic solvents produces several magic molecular clusters.”
`Ex. 1008, 95. A “starting procedure” results in “production of crystalline
`powders composed of well known pyramidal Zn4O(OAC)6-clusters” where
`“OAC” represents “acetate.” Id. at 86. Ptatschek employs those known
`crystalline powders in a chemical reaction to form a product that, upon
`study, “revealed the presence of Zn10O4(OAC)12-clusters associated with 7
`ethanol ligands and 1 water molecule. Id. Ptatschek reports, “The results of
`this detailed structural study will be published in the near future.” Id.
`4. Braun, Yu, Lucey, and Ahrenkiel
`Petitioner asserts Braun, Yu, Lucey, and Ahrenkiel in one or more
`
`grounds advanced in the Petition. Pet. 16–17. We make no findings
`pertaining to these references because none is necessary to our analysis.
`E. Ground that Asserts Banin
`Petitioner asserts that claims 1–6, 16, and 17 are unpatentable as
`
`obvious over Banin and Braun. Pet. 16. Our analysis of independent claim 1
`applies with equal force to dependent claims 2–6, 16, and 17.
`We organize this section into three subparts, addressing in turn (1) a
`dispositive issue whether Petitioner demonstrates, by a preponderance of the
`evidence, that Banin discloses MCCs; (2) an alternative theory of
`unpatentability, raised for the first time in the Reply, that an ordinarily
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`skilled artisan would have replaced “the small gold clusters” in Banin’s
`process with known MCCs not identified with particularity by Petitioner;
`and (3) our conclusions on this ground.
`1. Whether Banin’s “small Au clusters” are MCCs
`This challenge depends on Petitioner’s assertion that Banin discloses
`small gold clusters that are MCCs. Pet. 31. For reasons that follow, we find
`Petitioner does not show persuasively that Banin’s “small Au clusters” (also
`referred to herein as Banin’s “Au-based clusters,” “gold clusters,” “gold
`cluster catalysts,” and “metal catalysts”) are MCCs.
`For reasons explained in our claim construction analysis, we apply the
`construction assigned by the District Court, under which MCCs are “clusters
`of three or more metal atoms and their associated ligands of sufficiently
`well-defined chemical structure such that all molecules of the cluster
`compound possess approximately the same relative molecular formula.”
`Ex. 1091, 18. According to Petitioner, Banin’s Au-based clusters are MCCs.
`Pet. 25; Ex. 1002 ¶ 103. To support that position, Petitioner directs us to
`Banin’s disclosure that the Au-based clusters have “the suggested formula
`Au101(PPh3)21Cl5” (Ex. 1005, 20:12–27) and the testimony of Dr. Green
`(Ex. 1002 ¶¶ 101–103). Pet. 31–32.
`Dr. Green testifies, “It is my opinion that a [person of ordinary skill in
`the art] would have understood that the gold clusters Au101(PPh3)21Cl5” in
`Banin’s process “are ‘clusters of 3 or more metal’ atoms (i.e., because the
`other atoms of the clusters, (PPh3)21Cl5, are the ligands), and their associated
`ligands’ and that each cluster is ‘identical to one another.’” Ex. 1002 ¶ 102
`(citing Ex. 1055, 4:61–5:12). Dr. Green continues, “That is supported by
`Banin’s disclosure that the Au clusters ‘provid[e] large seeds for rapid InAs
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`[nanoparticle] growth.’” Id. (citing Ex. 1005, 23:24–27). Dr. Green
`considers the gold clusters to have a “sufficiently well-defined chemical
`structure such that all molecules of the cluster compound possess
`approximately the same relative molecular formula” because each cluster is
`identical and promotes Banin’s seeded synthetic reaction. At the petition
`stage, that is essentially the extent of Petitioner’s and Dr. Green’s
`explanation for their view that Banin’s gold clusters are MCCs. Pet. 31–32.
`Patent Owner counterargues that “Banin does not disclose [an] MCC.”
`Resp. 30; see Ex. 2030 ¶¶ 99–131 (Dr. Cossairt’s opinions, and citations to
`supporting evidence, explaining why Banin’s gold clusters are not MCCs).
`According to Patent Owner, Banin’s gold clusters “do not have a sufficiently
`well-defined chemical structure such that all molecules of the cluster
`compound possess the same relative molecular formula,” as required for
`MCCs. Resp. 30. On that point, Patent Owner states that Banin does not
`describe its gold clusters as “identical to one another,” as Petitioner contends
`and, further, “Petitioner points to the formula Au101(PPh3)21Cl5,” which
`“Banin itself describes as “merely a ‘suggested formula.’” Id. at 32 (citing
`Ex. 1005, 20:13–16; Ex. 2030 ¶ 102; Pet. 31). In Patent Owner’s view,
`Banin’s clusters range in size, and “different sizes are averaged out” to
`estimate “that the average number of gold atoms is approximately 101.” Id.
`at 30 (Patent Owner’s emphasis) (citing Ex. 2030 ¶¶ 105–106); see id. at 33
`(quoting Ex. 2017, 12891 for this same proposition).
`
`A preponderance of the evidence supports Patent Owner’s position.
`Compare Ex. 1002 ¶¶ 101–103 (Dr. Green’s testimony and cited evidence),
`with Ex. 2030 ¶¶ 99–131 (Dr. Cossairt’s testimony and cited evidence).
`Banin discloses that the Au clusters are “synthesized by the published
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`procedures” in Hutchison.16 Resp. 32 (citing Ex. 1005, 2:25–26, 20:13–16;
`Ex. 2030 ¶ 104). As Dr. Cossairt points out, the gold cluster catalysts in
`Banin’s process are not well-defined and are assigned the molecular formula
`Au101(PPh3)21Cl5 based on a calculation that relies on the average of a range
`of particle sizes that result from the method of Hutchison. Ex. 2030 ¶¶ 103–
`105 (citing Ex. 2017, 12891). Based on Dr. Cossairt’s comprehensive
`examination of Hutchison’s disclosure and other supporting evidence, Patent
`Owner provides detailed reasons why the clusters that Banin prepares
`according to Hutchison’s process do not qualify as MCCs within the scope
`of claim 1. Ex. 2030 ¶¶ 99–131; Resp. 32–44.
`Specifically, referring to Hutchison Figure 1(a), reproduced below,
`Dr. Cossairt testifies, “The Hutchison process creates gold particle
`agglomerations of many different sizes.” Ex. 2030 ¶ 104.
`
`
`16 Weare et al., Improved Synthesis of Small (dCORE ≈ 1.5nm)Phosphine-
`Stabilized Gold Nanoparticles, 122 J. A J. AM. CHEM. SOC. 12890–12891
`(2000) (“Hutchison,” Ex. 2017).
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`Ex. 2017, 12891, Fig. 1(a). Dr. Cossairt testifies that Hutchison’s Figure 1(a)
`“is a transmission electron microscopy [TEM] image along with an
`imbedded histogram that shows the size distribution of the gold particles.”
`Ex. 2030 ¶ 104. She also testifies that this figure shows, and the histogram
`confirms with its variety of differently sized black dots, that the sizes of the
`gold clusters prepared by Hutchison’s process vary by “a size difference
`ranging from 0.75 nm to 2.25 nm.” Id.
`Dr. Cossairt further testifies that, in Hutchison’s process, “[t]hese
`different sizes [of gold clusters] are averaged out, and then using the average
`size of the particle[s], it is estimated that the average number of gold atoms
`[in the metal core] is approximately 101.” Id. ¶ 105 (citing Ex. 2017, 12891).
`Additionally, as Dr. Cossairt observes, Hutchison uses the tilde symbol, “~”,
`when referring to the estimated particle size, i.e., “~101,” which indicates
`that the disclosed particle size of 101 is “only an approximate formula for an
`average-sized particle, not a well-defined formula.” Id. In other words, both
`Banin and Hutchison assign a “suggested” value of 101 to the gold in the
`clusters. Compare Ex. 1005, 2:25–26, 20:13–16 (Banin, assigning a
`“suggested” formula to the gold clusters), with Ex. 2017, 12891 (Hutchison,
`assigning the same “estimated” formula as Banin to the gold clusters).
`Dr. Cossairt asserts that Hutchison’s Figure 1(a) provides “[d]irect
`evidence of nanoparticle size and dispersity.” Ex. 2030 ¶ 106 (quoting
`Ex. 2017, 12890). According to Dr. Cossairt, the histogram of Figure 1(a)
`shows that the overall size variation, or dispersity, for the gold clusters
`resulting from Hutchison’s process is over 25%, which “is not considered
`monodisperse in the art.” Id. ¶ 107 (citing Ex. 2017, 12890).
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`Dr. Cossairt further testifies that an ordinarily skilled artisan “would
`understand that the claimed [MCC] would, at the very least, need to be able
`to be chemically characterized,” Petitioner acknowledges that Banin does
`not “actually chemically characterize the gold clusters produced by the
`Hutchison process,” and that both Banin and Hutchison “rely upon an
`average gold droplet size” and “theoretical assumptions that provide only a
`potential estimated average formula.” Id. ¶ 108 (citing Ex. 1005, 20:12–15;
`Ex. 1010, 9198; Ex. 2017, 12891). Dr. Cossairt continues, “By its nature, an
`uncharacterized particle that has only an average value assigned to a broad
`distribution of particle sizes cannot be a ‘sufficiently well-defined chemical
`structure such that all molecules of the cluster compound possess the same
`relative molecular formula.’” Id.
`In addition, Dr. Cossairt testifies, “By using particles that are not
`sufficiently well-defined,” Banin’s process cannot achieve the stated “goal
`of the ’557 patent, which is to make a population of semiconductor
`nanoparticles that is essentially monodisperse.” Id. ¶ 110 (citing Ex. 1001,
`19:16–21). Dr. Cossairt directs us to disclosures within the four corners of
`Banin, which indicate that “the diameter of the nanorods is dictated by the
`size of the gold particle” and that “the diameter of Banin’s nanorods vary by
`up to 25%, just like the gold particles do.” Id. (citing Ex. 1005,