The Board of Trustees of the University of Arkansas

Patent Trials and Appeals Board

Aug 16, 2021

IPR2020-00503 (P.T.A.B. Aug. 16, 2021)

Trials@uspto.gov
571-272-7822
Paper 27
Entered: August 16, 2021
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________
NANOSYS, INC.,
Petitioner,
v.
THE BOARD OF TRUSTEES OF THE UNIVERSITY OF ARKANSAS,
Patent Owner.
____________
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____________
Before JEFFREY W. ABRAHAM, RAE LYNN P. GUEST, and
JULIA HEANEY, Administrative Patent Judges.
HEANEY, Administrative Patent Judge.
JUDGMENT
Final Written Decision
Determining No Challenged Claim Unpatentable
37 C.F.R. § 318
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I. INTRODUCTION
Nanosys, Inc. (“Petitioner”) filed a Petition to institute an inter partes
review of claims 1–11 and 13–23 of U.S. Patent No. 7,105,051 B2
(Ex. 1001, “the ’051 patent”). Paper 2 (“Petition” or “Pet.”). The Board of
Trustees of the University of Arkansas (“Patent Owner”) filed a Preliminary
Response. Paper 7 (“Prelim. Resp.”). Taking into account the arguments
presented in Patent Owner’s Preliminary Response, we determined the
information presented in the Petition established that there was a reasonable
likelihood that Petitioner would prevail in challenging at least one of claims
1–11 and 13–23 of the ’051 patent, and we instituted this inter partes review
as to all challenged claims. Paper 8 (“Dec. on Inst.”).
During the course of trial, Patent Owner filed a Patent Owner
Response (Paper 11, “PO Resp.”); Petitioner filed a Reply to the Patent
Owner Response (Paper 16, “Pet. Reply”); Patent Owner filed a Sur-reply
(Paper 23, “PO Sur-reply”). An oral hearing was held on May 19, 2021, and
a transcript of the hearing is included in the record. Paper 26 (“Tr.”).
We have jurisdiction under 35 U.S.C. § 6. This decision is a Final
Written Decision under 35 U.S.C. § 318(a) as to the patentability of claims
1–11 and 13–23 of the ’051 patent. For the reasons discussed below, we
hold that Petitioner has not established by a preponderance of the evidence
that any of the challenged claims are unpatentable.
II. BACKGROUND
A. Related Proceedings
The parties identify NNCrystal US Corp. v. Nanosys, Inc., C.A. No.
1:19-cv-01307 (RGA) (D. Del.) as a related matter. Pet. 2; Paper 5, 1.
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B. The ’051 Patent
The ’051 patent is titled “High Quality Colloidal Nanocrystals and
Methods of Preparing the Same in Non-Coordinating Solvents.” Ex. 1001,
code (54). According to the ’051 patent, colloidal nanocrystals are of great
interest for industrial applications and academic studies due to their unique
size-dependent properties and flexible processing chemistry. Id. at 1:44–47.
The ’051 patent explains that conventional synthesis schemes were
sometimes irreproducible, often provided low quality crystals, possessed
high polydispersities, were plagued by impurities, and required the use of
toxic, pyrophoric, and unstable reagents. Id. at 1:58–65. The ’051 patent
also explains that conventional synthesis methods for high quality
nanocrystals used coordinating solvents or mixtures of several coordinating
reagents as a solvent, which made it difficult to identify an appropriate
solvent system for crystal growth. Id. at 2:41–66.
In view of these problems, the ’051 patent identifies a need for an
improved method of preparing nanocrystals that avoids the toxic solvents
commonly used, provides greener approaches using more recyclable
solvents, uses solvents that are liquid at room temperature to provide lower
costs, and imparts the ability “to control the size of the nanocrystals
produced, without sacrificing the desired narrow size distribution.” Id. at
3:8–19. The ’051 patent states “[t]he present invention demonstrates that,
despite the general belief that coordinating solvents are necessary for
preparing semiconductor nanocrystals, these materials may in fact be
prepared in non-coordinating solvents.” Id. at 20–23.
The ’051 patent discloses providing colloidal nanocrystals that, in
their as-prepared state, luminesce between about 500–700 nm, and are
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highly monodispersed. Id. at 3:31–35. The ’051 patent explains that “[h]igh
quality colloidal nanocrystals are nanometer sized fragments formed in
solution with well-controlled size, shape, surface structures, and excellent
chemical processibility.” Id. at 1:40–43. With regard to processing, the
’051 patent discloses “a method of synthesizing semiconductor nanocrystals
by combining a cation precursor, a ligand, and a non-coordinating solvent to
form a cation-ligand complex and then admixing an anion precursor
dissolved in a non-coordinating solvent with the cation-ligand complex at a
temperature sufficient to form nanocrystals.” Id. at 4:6–12.
The ’051 patent explains that non-coordinating solvents allow more
environmentally innocuous precursors and ligands to be used, and provides a
greener and less expensive synthesis method. Id. at 3:65–4:3. The ’051
patent describes four guidelines for selecting a non-coordinating solvent for
preparing high quality semiconductor nanocrystals (id. at 8:64–9:20) and
based on these guidelines, states that technical grade octadecene (ODE) is a
good choice as a non-coordinating solvent. Id. at 4:4–5; 9:25–27. The ’051
patent also states “in some preparations, certain ethers can constitute
reasonable non-coordinating solvents.” Id. at 9:39–40. The ’051 patent
states that “cation precursors can be elements, covalent compounds, or ionic
compounds, including coordination complexes or a metal salt, that serve as a
source for the electropositive element or elements in the resulting
nanocrystal” and “[a]nion precursors can also be elements, covalent
compounds, or ionic compounds that serve as a source for the
electronegative element or elements in the resulting nanocrystal.” Id. at
4:12–16, 4:18–21. For instance, the ’051 patent explains that its methods are
generally applicable to nanocrystals prepared from cation precursor
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compounds of group II metals, group IV metals, or transition metals and
anion precursors selected from the element itself, covalent compounds, or
ionic compounds of group V elements, group VI elements, or group VII
elements. Id. at 4:28–35, 4:45–49. According to the ’051 patent, “the ligand
is selected from fatty acids, amines, phosphines, phosphine oxides, or
phosphonic acids” in a typical preparation. Id. at 4:42–44.
C. The Challenged Claims
Petitioner challenges claims 1–11 and 13–23 of the ’051 patent.
Pet. 1. Claims 2–11 and 13–21 depend from claim 1, and claim 23 depends
from claim 22. Claim 1, reproduced below, is illustrative of the subject
matter of the challenged claims:
1. A method of synthesizing colloidal nanocrystals,
comprising:
a) combining a cation precursor, a ligand, and a
noncoordinating solvent to form a cation-ligand
complex; and
b) admixing an anion precursor with the cation-ligand
complex at a temperature sufficient to form
nanocrystals.
Ex. 1001, 19:26–33.
Claim 22, the other independent claim challenged by Petitioner, is
reproduced below:
22. A method of synthesizing colloidal nanocrystals,
comprising:
a) combining a cation precursor, a ligand, and a
noncoordinating solvent to form a cation-ligand
complex; and
b) admixing an anion precursor with the cation-ligand
complex at a first temperature sufficient to induce
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reaction between the cation-ligand complex and the
anion precursor; and
c) adjusting the temperature of the mixture to a second
temperature sufficient to form nanocrystals of the
reaction product.
Ex. 1001, 20:24–34.
D. Instituted Grounds of Unpatentability
We instituted trial to determine whether the challenged claims are
unpatentable based on the following grounds:
Ground Challenged
Claim(s)
35 U.S.C.
§1
Reference(s)/Basis
1 1–9, 11, 14, and 21 102(b) Trentler2
2 10 103 Trentler, Aldrich
Catalog3
3 2, 3, 15–18 103 Trentler, Murray 19934
4 13 103 Trentler
5 4, 19, 20 103 Trentler, Alivisatos5
6 1–9, 11, 13, 14, 19–
21
103 Alivisatos, Trentler
7 22, 23 102(b) Gao6

1 The Leahy-Smith America Invents Act (“AIA”) included revisions to 35
U.S.C. § 103 that became effective on March 16, 2013. Because the ’051
patent issued from an application filed before March 16, 2013, we apply the
pre-AIA versions of the statutory bases for unpatentability.
2 Trentler, T.J., et al., “Synthesis of TiO2 Nanocrystals by Nonhydrolytic
Solution-Based Reactions,” J. Am. Chem. Soc., 121(5), 1613–1614 (1999)
(Ex. 1005)
3 Aldrich Catalog Handbook of Fine Chemicals 199 (1997) (Ex. 1006).
4 Murray, C.B., et al., “Synthesis and Characterization of Nearly
Monodisperse CdE (E = S, Se, Te) Semiconductor Nanocrystallites,” J. Am.
Chem. Soc., 115(19), 8706–15 (1993) (Ex. 1022).
5 U.S. Patent No. 5,505,928 to Alivisatos et al. (Ex. 1008).
6 Gao, S., et al., “Study on the factors affecting the particles size of GaP
nanocrystalline materials,” Journal of Crystal Growth, 192(1-2), 89–92
(1998) (Ex. 1009).
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Ground Challenged
Claim(s)
35 U.S.C.
§1
Reference(s)/Basis
8 22, 23 102(b) Alivisatos
Pet. 3. Petitioner relies on the Declaration of Dr. Jonathan S. Owen.
(Ex. 1003) and Second Declaration of Dr. Jonathan S. Owen (Ex. 1027).
Patent Owner relies on the Declaration of Dr. Javier Vela-Becerra (“Dr.
Vela”) (Ex. 2001).
III. ANALYSIS
A. Claim Construction
In the Institution Decision, we determined that the preamble claim
term “method for synthesizing colloidal nanocrystals,” if it were given
patentable weight, should be construed to encompass methods for producing
nanocrystals that are dispersed as a colloid or could be dispersed as a
colloid, as argued by Petitioner.
For the reasons set forth in the discussion below, we have determined
it is not necessary to further address the parties’ dispute as to the
construction of “method for synthesizing colloidal nanocrystals” in order to
resolve each of Petitioner’s grounds of unpatentability against the challenged
claims. See Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co., 868
F.3d 1013, 1017 (Fed. Cir. 2017) (“we need only construe terms ‘that are in
controversy, and only 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. 2011)). Therefore, for purposes of this Decision, we do not
construe any claim term.
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B. Level of Ordinary Skill in the Art
Factors pertinent to a determination of the level of ordinary skill in the
art include “(1) educational level of the inventor; (2) type of problems
encountered in the art; (3) prior art solutions to those problems; (4) rapidity
with which innovations are made; (5) sophistication of the technology; and
(6) educational level of workers active in the field.” Envtl. Designs, Ltd. v.
Union Oil Co., 713 F.2d 693, 696–697 (Fed. Cir. 1983) (citing Orthopedic
Equip. Co. v. All Orthopedic Appliances, Inc., 707 F.2d 1376, 1381–82 (Fed.
Cir. 1983)). Not all such factors may be present in every case, and one or
more of these or other factors may predominate in a particular case. Id.
In our Institution Decision, we adopted Petitioner’s formulation of the
level of ordinary skill in the art and determined that a person of ordinary
skill in the art at the time of the invention “in the field of the ’051 patent
would have had knowledge of scientific literature and skills relating to that
field, including the synthesis of nanocrystals before July 30, 2001” and a
person of ordinary skill in the art “would have had a Masters or Ph.D. in
chemistry or material sciences, or a related discipline, with at least three
years of experience in the field of nanocrystal synthesis.” Dec. on Inst.
13–14 (adopting Petitioner’s formulation, as supported by Dr. Owen’s
testimony, because it is consistent with the ’051 patent and the asserted prior
art.). Patent Owner does not dispute the level of ordinary skill in the art.
See Ex. 2001 ¶ 25. Accordingly, having considered the arguments and
evidence, we maintain our determination from the Institution Decision
adopting Petitioner’s proposed level of ordinary skill in the art, as it is
consistent with the problems and solutions in the ’051 patent and prior art of
record.
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C. Principles of Law
“Anticipation requires that every limitation of the claim in issue be
disclosed, either expressly or under principles of inherency, in a single prior
art reference,” Corning Glass Works v. Sumitomo Elec. U.S.A., Inc., 868
F.2d 1251, 1255–56 (Fed. Cir. 1989), and that the claim limitations be
“arranged or combined in the same way as recited in the claim,” Net
MoneyIN, Inc. v. VeriSign, Inc., 545 F.3d 1359, 1371 (Fed. Cir. 2008).
However, “the reference need not satisfy an ipsissimis verbis test.” In re
Gleave, 560 F.3d 1331, 1334 (Fed. Cir. 2009).
A claim is unpatentable under 35 U.S.C. § 103 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.” KSR Int’l Inc. v. Teleflex Inc., 550 U.S. 398, 406
(2007). The question of obviousness is resolved on the basis of underlying
factual determinations, including (1) the scope and content of the prior art;
(2) any differences between the claimed subject matter and the prior art; (3)
the level of ordinary skill in the art; and (4) when available, evidence such as
commercial success, long felt but unsolved needs, and failure of others.
Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966); see KSR, 550 U.S. at
407 (“While the sequence of these questions might be reordered in any
particular case, the [Graham] factors continue to define the inquiry that
controls.”).
The Supreme Court made clear that we apply “an expansive and
flexible approach” to the question of obviousness. KSR, 550 U.S. at 415.
Whether a patent claiming the combination of prior art elements would have
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been obvious is determined by whether the improvement is more than the
predictable use of prior art elements according to their established functions.
Id. at 417. Reaching this conclusion, however, requires more than merely
showing that the prior art includes separate references covering each
separate limitation in a challenged claim. Unigene Labs., Inc. v. Apotex,
Inc., 655 F.3d 1352, 1360 (Fed. Cir. 2011). Rather, obviousness
additionally requires that a person of ordinary skill at the time of the
invention “would have selected and combined those prior art elements in the
normal course of research and development to yield the claimed invention.”
Id.
D. Ground 1: Alleged Anticipation Based on Trentler
Petitioner argues that claims 1–9, 11, 14, and 21 are anticipated by
Trentler. Pet. 16–23.
Trentler (Ex. 1005)
Trentler is titled “Synthesis of TiO2 Nanocrystals by Nonhydrolytic
Solution-Based Reactions.” Ex. 1005, 1613. Trentler discloses a procedure
for making nanocrystalline materials in which a titanium halide is mixed
with distilled trioetylphosphine oxide (TOPO) in heptadecane and heated to
300 °C under dry nitrogen. Id. at 1613. Subsequently, a metal alkoxide is
rapidly injected into the hot solution, with high reactant concentrations
leading “to the formation of off-white precipitates which could be recovered
as powders” while lower reactant concentrations provide clear, orange
solutions. Id. Trentler describes isolating reaction precipitates via
centrifugation and washing with acetone. Id. According to Trentler, the
powders obtained were anatase TiO2, and X-ray diffraction line widths
indicated crystalline domains under 10 nm in diameter. Id.
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Claim 1
Petitioner contends that Trentler describes in detail the procedures,
conditions, and reagents used in successfully synthesizing nanocrystals
capable of forming a colloid in a solvent (Pet. 18 (citing Ex. 1003 ¶ 100)),
and given the high level of skill in the art, a person of ordinary skill would
have readily been able to repeat Trentler’s procedures. Id. Petitioner further
contends Trentler describes two products of its synthesis, i.e. “[p]owders
having crystalline domains under 10 nm diameter” and “redispersed”
nanocrystals. Id. at 17 (citing Ex. 1005, 1613). Petitioner contends that the
powders under 10 nm diameter could have formed a colloid in a solvent, and
that the “redispersed” nanocrystals were colloidal because they were
dispersed in solution. Id. (citing Ex. 1003 ¶ 99).
“cation-ligand complex”
Claim 1 recites “combining a cation precursor, a ligand, and a non-
coordinating solvent to form a cation-ligand complex.” Ex. 1001, 19:28–29.
Petitioner contends that Trentler discloses a nanocrystal synthesis in which a
titanium halide ‘“was mixed with distilled trioctylphosphine oxide’ (TOPO)
‘in heptadecane.’” Pet. 16 (citing Ex. 1003 ¶¶ 91–92; Ex. 1005, 1613).
Petitioner contends that a person of ordinary skill in the art would have
understood that a titanium halide was a cation precursor, TOPO was a
ligand, and heptadecane was a non-coordinating solvent, according to the
’051 patent (id. (citing Ex. 1003 ¶¶ 92–95); Pet. Reply 6–7), and further
would have understood from Trentler’s disclosure that titanium iodide and
TOPO form a cation-ligand complex when heated to 300 °C, because the
electron pairs of TOPO bind to titanium. Id. at 17 (citing Ex. 1003 ¶ 96;
Ex. 1005, 1613); see also Pet. Reply 5–6; Ex. 1027 ¶ 24 (“titanium halides,
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such as TiI4, are powerful Lewis acids capable of binding with weakly
coordinating ligands including ethers, water, and TOPO.”).
Petitioner further contends that a person of ordinary skill in the art
would have understood that Trentler discloses a cation-ligand complex in
view of background prior art, Poleshchuk7 (Ex. 1054). Pet. Reply, 6 (citing
Ex. 1003 ¶ 96; Ex. 1027 ¶ 23–25; Ex. 1054, 58). Petitioner relies on Dr.
Owen’s testimony that a person of ordinary skill in the art would have
understood that Poleshchuk shows TiCl4, one of the titanium halides
mentioned by Trentler, forms a ligand-cation complex with Ph3PO in a non-
coordinating solvent, carbon tetracholoride. Id. (citing Ex. 1027 ¶ 25).
According to Dr. Owen, a person of ordinary skill would have expected
TOPO would be more likely to form a cation-ligand complex than Ph3PO
because TOPO is a stronger binder. Ex. 1027 ¶ 25 (citing Ex. 1054, 16; Ex.
1061, 6).
Patent Owner contends that Trentler does not expressly disclose the
formation of a cation-ligand complex.9 PO Resp. 19–20. Patent Owner
contends that Trentler instead describes TOPO “as a ‘passivating agent’ and
‘surface capping group’ that coordinates to the surface of a nanocrystal, not
as an agent that forms a cation-ligand complex with titanium.” Id. at 20
(citing Ex. 1005, 7; Ex. 2001 ¶ 105). Patent Owner further contends that
Trentler does not describe any indicia of the formation of a cation-ligand

7 Poleshchuk, O.Kh., et al., “Electron Density Redistribution on
Complexation in Non-transition Element Complexes,” J. Mol. Structure,
297, 295 (1993).
8 We refer to the page numbers of Exhibit 1054 assigned by Petitioner.
9 Petitioner does not contend that Trentler inherently discloses formation of
a cation-ligand complex. Pet. Reply 6.
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complex, such as solubilizing of the cation precursor, a color change, or a
precipitate (PO Sur-reply 5 (citing Ex. 1005, 7; Ex. 1027 ¶¶ 23–25)), unlike
the ’051 patent and Poleshchuk, which demonstrate complex formation by
an optically clear solution and precipitation, respectively. Id. at 5–6 (citing
Ex. 1001, 16:22–18:26; Ex. 1053, 43:12–45:24, 48:5–49:14, 52:1–16; Ex.
2001, 126 (App. A), 131 (App. B); Ex. 1054, 5; Ex. 2041, 36:2–10). As to
Poleshchuk, Patent Owner contends it provides no support for what a person
of ordinary skill in the art would infer from Trentler, because it describes
reactions different from those taught by Trentler and provides examples of
mixing Lewis acids and bases that do not result in the formation of any
complex. Id. at 9 (citing Ex. 1005, 7; Ex. 1054, 5, 7, 10; Ex. 2041, 18:22–
28:7, 30:22–32:8, 33:4–35:24, 36:2–20, 39:23–40:7, 43:8–18, 47:19–50:3).
Patent Owner also disputes that a person of ordinary skill would have
expected TOPO to be more likely to form a cation-ligand complex than
Poleshchuk’s Ph3PO because TOPO is a stronger binder; Patent Owner
asserts that Tolman10 (Ex. 1061) contradicts Dr. Owen’s opinion that TOPO
is a stronger binder. Id. at 10 (citing Ex. 1027 ¶ 25; Ex. 1061, 6, 13; Ex.
2041, 126:7–128:25; 135:17–137:20).
Patent Owner further contends that Dr. Owen’s testimony that a
person of ordinary skill in the art would have understood that Trentler
discloses a cation-ligand complex is irreconcilable with how Trentler has
been addressed in other literature in the art, which does not recognize
Trentler’s reaction as forming a cation-ligand complex. PO Sur-reply 7–8
(citing Ex. 2023, 17, 20; Ex. 2024, 10, 23, 24; Ex. 2025, 12, 25, 37, 60;

10 Tolman, C.A., “Steric Effects of Phosphorous Ligands in Organometallic
Chemistry and Homogeneous Catalysis,” Chem. Rev. 77: 313–348 (1977).
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Ex. 2026, 14, 25, 34, 36, 41; Ex. 2028, 1, 2, 8). Also, Dr. Vela testifies that
some literature in the art, unlike Trentler, explicitly reported formation of a
cation-ligand complex. See PO Sur-reply 9 (citing Ex. 2001 ¶¶ 102–103;
Ex. 1018, 9; Ex. 2007, 4).
Having considered the arguments and evidence of record, it is
undisputed that Trentler does not expressly disclose the formation of a
cation-ligand complex. As to whether a person of ordinary skill in the art
would have understood Trentler to disclose the formation of a cation-ligand
complex, we are not persuaded by Petitioner’s argument that Poleshchuk
would have led a person of ordinary skill to understand Trentler as
disclosing a cation-ligand complex. Although Dr. Owen’s testimony that a
person of ordinary skill in the art would have expected Trentler’s TOPO to
form a cation-ligand complex with TiCl4 because Poleshchuk’s Ph3PO forms
a cation-ligand complex with TiCl4 has a rational basis in its comparison of
TOPO and Ph3PO’s structures (see Ex. 1027 ¶ 25), Petitioner and Dr. Owen
fail to consider the effects of other differences between Poleshchuk’s and
Trentler’s reactions, such as thermal conditions and solvent differences.
E.g., Ex. 1005, 7; 1054, 5; Ex. 2041, 18:22-28:7, 43:8-18. Further,
Petitioner and Dr. Owen do not address that Poleshchuk’s reaction
description includes formation of a precipitate, which indicates formation of
a cation-ligand complex, whereas Trentler does not describe any indicia of
formation of a complex. See Ex. 1027 ¶¶ 23–25. In view of the other
literature referencing Trentler that Patent Owner identifies, as discussed
below, Poleshchuk is not persuasive evidence that a person of ordinary skill
would have understood Trentler to disclose formation of a cation-ligand
complex.
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We also credit Dr. Vela’s testimony that Trentler describes TOPO as a
“passivating agent” and a “surface capping group” that coordinates the
surface of titanium atoms at the surface of the nanocrystal, not as an agent
that forms a complex with the titanium cation precursor. Ex. 2001 ¶ 105.
Trentler’s description of its TiO2 nanocrystals and their synthesis states:
These particles are highly dispersible in hydrocarbon
solvents due to the coordination of surface titanium
atoms to passivating agents employed during the
reaction. The use of coordination chemistry to
stabilize the nanocrystals allows for ready exchange
of surface capping groups which should provide
control over the surface and consequently over
properties.
Ex. 1005, 1613. Trentler subsequently states that “[t]he amount of
passivating agent (TOPO) present in the reactions also clearly influences the
chemistry.” Id. at 1614. Thus, Trentler itself supports Dr. Vela’s testimony.
Further, Dr. Vela’s opinion is consistent with literature in the art that
does not recognize Trentler’s reaction as forming a cation-ligand complex.
Patent Owner points to numerous references (Exs. 2023, 2024, 2025, 2026,
2028) that summarize Trentler without mentioning formation of a cation-
ligand complex, while expressly recognizing other reactions that formed
cation-ligand complexes. Petitioner does not dispute the teachings of these
references.
We do not find persuasive Petitioner’s argument that Dr. Vela’s
testimony that a person of ordinary skill in the art “would have understood
each example in the ’051 patent described the formation of a ‘cation-ligand
complex’ even though none of those examples explicitly mention such
complexes” (Pet. Reply 5) undercuts his opinion as to Trentler’s lack of
disclosure of a cation-ligand complex. Dr. Vela’s opinion is not merely
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based on the absence of an express disclosure of “cation-ligand complex” in
Trentler, but also on the absence of any indicia of the formation of a cation-
ligand complex. Further, Petitioner mischaracterizes Dr. Vela’s testimony
about complex formation; he did not testify “any POSA could have looked
at a given reaction and known whether” a cation-ligand complex formed (see
Pet. Reply 6), but rather opined that a person of ordinary skill in the art
would have understood the ’051 patent’s examples describe formation of a
cation-ligand complex in the context of the entire patent, including
experimental indications such as a color change. Ex. 1053, 44–58.
At most, Dr. Owen’s testimony (Ex. 1003 ¶ 96; Ex. 1027 ¶¶ 24–25)
demonstrates that a person of ordinary skill would have understood
Trentler’s reaction as capable of forming a cation-ligand complex under
certain conditions. Even if a person of ordinary skill in the art would have
understood Trentler’s titanium halide to be capable of binding with a weakly
coordinating ligand such as TOPO, however, that does not sufficiently
demonstrate that Trentler discloses formation of a cation-ligand complex, for
the purpose of finding anticipation.
Accordingly, we determine Petitioner has not carried its burden to
demonstrate by a preponderance of the evidence that Trentler discloses
formation of a cation-ligand complex, as required by claim 1.
Claims 2–9, 11, 14, and 21
Claims 2–9, 11, 14, and 21 each depend from claim 1. Petitioner’s
arguments with respect to dependent claims 2–9, 11, 14, and 21 do not
address the deficiency discussed above with respect to claim 1. See Pet. 16–
23.
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Conclusion
For the foregoing reasons, we conclude that Petitioner has not
demonstrated by a preponderance of the evidence that claims 1–9, 11, 14,
and 21 are anticipated by Trentler.
E. Ground 2: Alleged Obviousness Based on Trentler and Aldrich
Catalog
Petitioner argues claim 10 would have been obvious over the
combined teachings of Trentler and the Aldrich Catalog. Pet. 24–30.
Petitioner’s obviousness arguments based on Trentler and the Aldrich
Catalog do not address or remedy the deficiency discussed above with
regard to formation of a cation-ligand complex. Thus, Petitioner has not
demonstrated by a preponderance of the evidence that claim 10 would have
been obvious over the combination of Trentler and Aldrich Catalog.
F. Ground 3: Alleged Obviousness Based on Trentler and Murray
1993
Petitioner argues claims 2, 3, and 15–18 would have been obvious
over the combined teachings of Trentler and Murray 1993. Pet. 31–37.
Petitioner’s obviousness arguments based on Trentler and Murray 1993 do
not address or remedy the deficiency discussed above with regard to
formation of a cation-ligand complex. Thus, Petitioner has not demonstrated
by a preponderance of the evidence that claims 2, 3, and 15–18 would have
been obvious over the combination of Trentler and Murray 1993.
G. Ground 4: Alleged Obviousness Based on Trentler
Petitioner argues dependent claim 13 would have been obvious over
the combined teachings of Trentler. Pet. 37–41. Petitioner’s obviousness
argument based on Trentler does not address or remedy the deficiency
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discussed above with regard to formation of a cation-ligand complex. Thus,
Petitioner has not demonstrated by a preponderance of the evidence that
claim 13 would have been obvious over Trentler.
H. Ground 5: Alleged Obviousness Based on Trentler and
Alivisatos
Petitioner argues dependent claims 4, 19, and 20 would have been
obvious over the combined teachings of Trentler and Alivisatos. Pet. 41–46.
Petitioner’s obviousness arguments based on Trentler and Alivisatos do not
address or remedy the deficiency discussed above with regard to formation
of a cation-ligand complex. Thus, Petitioner has not demonstrated by a
preponderance of the evidence that claims 4, 19, and 20 would have been
obvious over the combination of Trentler and Alivisatos.
I. Ground 6: Alleged Obviousness Based on Alivisatos and Trentler
Petitioner argues that the combined teachings of Alivisatos and
Trentler teach or suggest each limitation of claims 1–9, 11, 13, 14, and 19–
21. Pet. 46–58.
Overview of Alivisatos (Ex. 1008)
Alivisatos, titled “Preparation of III-V Semiconductor Nanocrystals”
discloses “reacting a group III metal source with a group V anion source in a
liquid phase at elevated temperature in the presence of a crystallite growth
terminator such as pyridine or quinolone.” Ex. 1008, codes (54), (57).
Alivisatos explains that a group III metal source can be “a GaIII salt, InIII
salt, or AIIII salt, especially halide, or corresponding metal 1-6 carbon
trialkyls” and “[r]epresentative metal sources include GaCl3, GaBr3, GaI3,
InCl3, InBr3, AlCl3, Ga(Me)3, Ga(Et)3, Ga(Bu)3, or the like.” Id. at 4:16–24.
Alivisatos states that “an arsenic, phosphorus, or antimony source” can serve
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as a group V anion source “such as arsine, phosphine, or stibine; an alkyl
arsine, phosphine or stibine; or an alkyl silyl arsine, phosphine or stibine in
liquid phase at an elevated temperature.” Id. at 4:18–22.
Alivisatos states that when preparing III–V compounds by reacting a
group III metal source with a group V nonmetal source, “the reaction
medium employed plays a big part in the III–V crystallite form ultimately
obtained” and “if a crystal growth terminator such as a nitrogen- or
phosphorus-containing polar organic solvent is present in place of the pure
nonpolar hydrocarbon of the art, one can obtain III-V crystallites which are
sized in the range 30-50 Å and which are relatively monodisperse and
redissolvable.” Id. at 2:3–12. Alivisatos further states that “[a]
distinguishing feature of the preparation process is that it is carried out in a
liquid reaction phase which includes at least one of these crystallite growth
terminators.” Id. at 3:31–33. According to Alivisatos, “[c]rystallite growth
terminators can include compounds which include a phosphorus or nitrogen
having an unshared pair of electrons” that “can complex with the metal and
bind to it, thereby presenting a surface which will prevent further crystal
growth.” Id. at 3:33–38.
Alivisatos includes six examples of preparation of III–V nanocrystals,
varying in the selection of the metal and nonmetal sources, reaction media,
and crystallite growth terminators. Alivisatos’s Example 6 combines
gallium and arsenide precursors in 15%/85% tributyl phosphine and a high-
boiling petroleum distillate, followed by heating the solution and allowing
the reaction to proceed at 300 °C for 20 hours to obtain a powder consisting
of GaAs particles which are redissolvable in pyridine or quinolone. Ex.
1008, 5:27–35, 6:30–35, 6:42–46.
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Combination of Alivisatos and Trentler
Petitioner contends that a person of ordinary skill in the art would
have understood that in Alivisatos’s Example 6, GaCl3 was the cation
precursor, tributylphosphine was the ligand, and high-boiling petroleum
distillate fraction was the non-coordinating solvent. Pet. 47 (citing Ex. 1003
¶ 211). Petitioner further contends a person of ordinary skill in the art would
have understood that the GaCl3 and tributylphosphine form a cation-ligand
complex because the electron pairs of tributylphosphine bound to Ga. Id.
Petitioner also contends that Alivisatos’s Example 6 discloses
tris(trimethylsilyl)arsine as an anion precursor combined with petroleum
distillate fraction, that was mixed with the GaCl3-tributylphosphine cation
ligand complex and heated at 300 °C for 20 hours to obtain a “red powder
[that] was isolated by removal of the solvent, and the powder consisted of
[semiconducting] particles which are redissolvable in pyridine or
quinolone.” Pet. 47–48 (citing Ex. 1008, 5:27–36, 6:31–35, 6:42–46; Ex.
1003 ¶ 213). Petitioner further contends a person of ordinary skill in the art
would have understood that the red powder consisted of nanocrystals
capable of forming a colloid in a solvent because they were redissolvable in
pyridine or quinolone and because Alivisatos further discloses “[f]lame
annealing of the powder under vacuum at 450 °C improved the crystallinity
of the particles.” Id. at 48 (citing Ex. 1008, 5:33–38; Ex. 1003 ¶ 213).
Petitioner contends that to the extent Alivisatos does not disclose
admixing “at a temperature sufficient to form nanocrystals,” it would have
been obvious to modify Alivisatos to incorporate Trentler’s hot-injection
method, for several reasons. Pet. 48 (citing Ex. 1003 ¶ 214). Petitioner
contends that Trentler describes hot injection as a method of nanocrystal
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synthesis involving injection of the solution containing the anion precursor
into a pre-heated solution containing the cation-ligand complex. Ex. 1003 ¶
214 (citing Ex. 1005, 1613).
Motivation to Combine
Petitioner contends that a person of ordinary skill in the art would
have been motivated to use Trentler’s hot-injection method to modify
Alivisatos’s heat-up method because hot injection was a “versatile maneuver
easily adaptable into known methods of synthesizing nanocrystals, and
capable of yielding higher quality nanocrystals” as compared to Alivisatos,
and therefore would improve it. Pet. 48–49 (citing Ex. 1022, 8715; Ex. 1003
¶ 215; Ex. 1005, 1613). Petitioner further contends a person of ordinary
skill in the art would have known that modifying Alivisatos by incorporating
Trentler’s hot-injection method would improve the quality of nanocrystals
(id. at 49–50 (citing Ex. 1003 ¶¶ 215–216; Ex. 1010, 4109; Ex. 1022, 8715))
and would have appreciated the interchangeability of Alivisatos’s and
Trentler’s heating methods because “both references reported synthesizing
nanocrystals despite varying the temperature.” Id. at 50 (citing Ex. 1003 ¶¶
215–216; Ex. 1005, 1613; Ex. 1008, 6:31–35, 44–46; Ex. 1022, 8715).
Patent Owner argues several reasons for why a person of ordinary
skill in the art would not have been motivated to modify Alivisatos with
Trentler as Petitioner proposes. PO Resp. 54–58. According to Patent
Owner, Alivisatos was published in an early stage in the nanocrystal
industry (1991), and over the next decade, other publications reported better
results and diminished its significance. Id. at 55 (citing Ex. 2001 ¶ 239; Ex.
1018, 8–9; Ex. 1016, 10–11). Patent Owner contends a person of ordinary
skill in the art would have known the difficulties of synthesizing Group III-
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V semiconductor nanocrystals as described in Alivisatos and would not have
been motivated to pursue the benefit of Trentler’s hot-injection method, as
Petitioner contends. Id. at 55–56 (citing Ex. 2001 ¶¶ 240–242; Ex. 1012, 8;
Ex. 1016, 10; Ex. 1018, 8).
Patent Owner further contends that even if a person of ordinary skill
in the art would have sought to modify Alivisatos to incorporate the hot-
injection method, there would have been no reason to select Example 6 over
other examples in Alivisatos. PO Resp. 56–57 (citing Ex. 2001 ¶¶ 214, 242–
243; Ex.1022, 4; Ex. 1012, 8 n. 22). Patent Owner contends a person of
ordinary skill in the art would instead have been guided toward the use of a
coordinating solvent system, as in the four examples of Alivisatos that use
quinolone or pyridine, because it was known that a coordinating solvent
system helped to avoid difficulties in synthesizing Group III-V nanocrystals.
Id.; PO Sur-reply 19–20.
Petitioner responds that difficulties in synthesizing Group III-V
nanocrystals, such as agglomeration and polydispersity, are irrelevant
because the challenged claims do not require uniformly sized or
monodisperse nanocrystals. Pet. Reply 14–16. Petitioner further responds
that one of the ’051 patent’s inventors in fact reported successful production
of a Group III-V semiconductor using the hot-injection method in 1998. Id.
at 16 (citing Ex. 1012, 9). Petitioner further contends that Patent Owner
misconstrues Alivisatos because it does not point to a coordinating solvent
as preferred, but rather points a person of ordinary skill to use a non-
coordinating solvent to synthesize InP and InAs (Group III-V) nanocrystals.
Id. at 16–17 (citing Ex. 1008, 4:2–5, 4:16–20, 6:37–46).
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We agree with Patent Owner that Petitioner has not demonstrated
sufficiently that a person of ordinary skill in the art would have modified
Alivisatos’s Example 6 with Trentler’s hot-injection method. In view of the
art Patent Owner points to that reported difficulties in preparing Group III-V
nanocrystals in non-coordinating solvents at high temperatures, Petitioner
does not adequately explain why a person of ordinary skill in the art would
have used Alivisatos’s Example 6, which used a non-coordinating solvent,
as a starting point, for trying to improve the quality of Alivisatos’s Group
III-V nanocrystals. Instead, Petitioner argues that the difficulties are
irrelevant because of the challenged claims’ scope. We disagree. For
purposes of an obviousness challenge, demonstrating a reason to combine
teachings in the prior art requires showing that a modification would have
been desirable, not merely feasible. Winner Intern. Royalty Corp. v. Wang,
202 F.3d 1340, 1349 (Fed. Cir. 2000); see also Belden Inc. v. Berk-Tek LLC,
805 F.3d 1064, 1073 (Fed. Cir. 2015) (“[O]bviousness concerns whether a
skilled artisan not only could have made but would have been motivated to
make the combinations or modifications of prior art to arrive at the claimed
invention.”). Although the reported difficulties may not be relevant to the
question of whether the proposed combination was altogether feasible, we
consider them to be relevant to the question of whether a person of ordinary
skill in the art would have had a reason to pursue such a combination.
Petitioner’s other arguments also are not persuasive in light of the art
of record as a whole. The publication describing use of a hot-injection
method with Group III-V semiconductors (see Pet. Reply 16) used a
coordinating solvent, trioctylphosphine. Ex. 1012, 8. Prior art submitted by
Patent Owner, as summarized above, on the whole suggests coordinating
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solvents were crucial to any improvement. Further, Alivisatos does not state
there is any advantage in Example 6 versus its four examples prepared in
coordinating solvents. Thus, we are persuaded by Patent Owner’s argument
that even if a person of ordinary skill in the art had been motivated to
improve the quality of Alivisatos’s nanocrystals, the skilled artisan would
not try do so with Trentler’s hot-injection method. Rather, according to the
art of record at the time of the invention as a whole, the artisan would have
used coordinating solvents to try and improve Group III-V nanocrystals,
rather than modifying Alivisatos’s Example 6.
Reasonable Expectation of Success
Petitioner contends a person of ordinary skill in the art would have
had a reasonable expectation of success in modifying Alivisatos with
Trentler’s hot-injection method because Trentler explicitly disclosed
successfully synthesizing nanocrystals using the hot-injection method, and
Alivisatos disclosed nanocrystal synthesis reactions similar to Trentler’s
reactions. Pet. 51–52 (citing Ex. 1003 ¶ 216; Ex. 1005, 1613; Ex. 1008,
4:54–65). Patent Owner contends there would have been no reasonable
expectation of success in modifying Alivisatos’s Example 6 to incorporate
Trentler’s hot-injection method. PO Resp. 58–59.
The parties’ evidence and arguments on this issue overlap
substantially with their evidence and arguments directed to motivation to
combine. Because we have determined Petitioner has not shown a
motivation to combine, it is not necessary to further address reasonable
expectation of success.
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Conclusion
For the reasons discussed above, we determine that Petitioner has not
demonstrated by a preponderance of the evidence that a person of ordinary
skill in the art would have had a reason to combine the teachings of
Alivisatos and Trentler. Therefore, Petitioner has not shown by a
preponderance of the evidence that the combination of Alivisatos and
Trentler renders claims 1–9, 11, 13, 14, and 19–21 obvious.
J. Ground 7: Alleged Anticipation Based on Gao
Petitioner argues that Gao anticipates claims 22 and 23. Pet. 58–61.
Gao (Ex. 1009)
Gao, titled “Study on the factors affecting the particles size of GaP
nanocyrstalline materials,” describes synthesizing GaP by reacting GaCl3–
Et2O and GaCl3–benzene with Na3P, respectively, at high temperature, high
pressure benzene-thermal conditions. Ex. 1009, 89. According to Gao,
when GaCl3–Et2O is used as a starting material, the empty p orbital of Ga
atoms coordinates with O atoms of Et2O to form “a rather strong Ga ← O
bond” that is difficult to break down during the reaction process, which
causes the Ga atoms in solution to be small and the particle size of GaP
crystals to be small with a narrow distribution. Id. at 91–92. Gao further
states that using GaCl3–Et2O as a starting material results in more perfect
crystal grains and a better particle size distribution than a sample prepared
from GaCl3–benzene as the starting material. Id. at 91.
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Claim 22
a first temperature sufficient to induce reaction between the
cation-ligand complex and the anion precursor
Petitioner contends that Gao discloses procedures for synthesizing
nanocrystals in which ether was used to extract GaCl3 and benzene was
added to the extracted GaCl3. Pet. 58 (citing Ex. 1009, 90; Ex. 1003 ¶¶ 267–
268). Petitioner contends that a person of ordinary skill in the art would
have understood that in Gao’s procedure, GaCl3 was a cation precursor,
ether was a ligand, and benzene was a non-coordinating solvent, and that the
GaCl3 and ether (Et2O ) form a cation-ligand complex. Id. (citing Ex. 1009,
90; Ex. 1003 ¶ 269). Petitioner further contends that Gao discloses
transferring the resulting solution containing GaCl3, ether, and benzene into
an autoclave, adding benzene and Na3P, which a person of ordinary skill
would recognize as an anion precursor, then sealing the autoclave. Id. at 59
(citing Ex. 1009, 90; Ex. 1003 ¶¶ 271–272). Petitioner contends Gao
discloses “admixing . . . at a first temperature sufficient to induce reaction
between the cation-ligand complex and the anion precursor” because a
person of ordinary skill in the art would have understood that “the strong
coordinating ability between GaCl3 and Na3P would cause the formation of a
Lewis acid-base adduct, even at room temperature.” Id. at 59–60 (citing Ex.
1003 ¶ 272). Petitioner and Dr. Owen rely on two publications, Wells
198911 (Ex. 1029) and Wells 199712 (Ex. 1020), as supporting Dr. Owen’s

11 Wells, R.L., et al., “Use of Tris(trimethylsilyl)arsine To Prepare Gallium
Arsenide and Indium Arsenide,” Chemistry of Materials, 1 (1989).
12 Wells, R.L., et al., “Pathways to Nanocrystalline II-V (13-15) Compound
Semiconductors,” Journal of Cluster Science, 8, 2 (1997).
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opinion that GaCl3 and Na3P would react at room temperature. Ex. 1003 ¶
272 (citing Ex. 1029, 4–5; Ex. 1020, 223).
Patent Owner contends Gao does not disclose admixing a cation-
ligand complex and anion precursor at room temperature to induce a reaction
between them. PO Resp. 60–61. Specifically, Patent Owner contends that
Gao describes
very extreme conditions for the reaction to occur,
including heating the reactants in an autoclave to 350–
380 °C, well above the boiling point of the solvent
(benzene), resulting in a high-pressure system . . . .
That Gao employed these extreme conditions
indicates that no reaction occurred at room
temperature.
Id. (citing Ex. 1009, 9013; Ex. 2001 ¶ 257). Patent Owner further contends
that Gao teaches it was difficult to initiate reaction between GaCl3-Et2O and
Na3P for several reasons: (1) Gao’s characterization of the Ga-O bond as
“rather strong;” (2) the equilibrium constant of the reaction; (3) the
understanding of a person of ordinary skill that reaction at room temperature
would have been deterred by the stability of the Ga-O bond and the low
solubility of the Na3P precursor in benzene. Id. at 61 (citing Ex. 1009, 92;
Ex. 2001 ¶¶ 255–257).
Patent Owner also contends that the Wells publications do not suggest
that a reaction would occur at room temperature. Id. at 61–62 (citing Ex.
1003 ¶ 272; Ex. 2001 ¶¶ 259–261). Specifically, Patent Owner contends
that neither of the Wells publications describes a reaction involving GaCl3-
Et2O and Na3P. Id.

13 We refer to the page numbering on Ex. 1009 that Petitioner referenced in
the Petition.
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Petitioner replies by disputing that Na3P is “relatively unreactive” and
that the GaCl3-Et2O complex must be broken for complexing with Na3P to
occur. Pet. Reply 22 (citing Ex. 1027 ¶¶ 39–42). Petitioner and Dr. Owen
rely on two publications, Bock14 (Ex. 1059) and Boardman15 (Ex. 1060) as
supporting Dr. Owen’s opinion that the GaCl3-Et2O complex need not be
broken, because GaCl3-Et2O “binds fifth ligands.” Ex. 1027 ¶¶ 41–42
(citing Ex. 1059, 3; Ex. 1060, 1). Petitioner also contends that a person of
ordinary skill in the art would have understood that GaCl3-Et2O “would have
reacted with the extraordinarily reactive Na3P before the reaction mixture
was heated to 350–380 °C” in Gao’s process (Pet. Reply 22 (citing Ex. 1027
¶ 42)).
Petitioner’s reply arguments do not persuasively explain why a person
of ordinary skill in the art would have understood that the cation-ligand
complex, GaCl3-Et2O, and anion precursor, Na3P, in Gao’s procedure react
at room temperature. As to the anion precursor Na3P, Dr. Owen’s assertion
that it is “extraordinarily reactive” appears to be based on a data sheet that
addresses its reactivity in water, not benzene, which is the solvent in Gao’s
procedure. See Ex. 1027 ¶ 39 (citing Ex. 1056). Further, Dr. Owen does not
dispute that Na3P is largely insoluble in benzene. See Ex. 2041, 139:2–4.
As to the GaCl3-Et2O cation ligand complex, Dr. Owen’s reliance on Bock
does not support Petitioner’s argument that the complex binds fifth ligands
because Bock states that the complex is tetracoordinated. Ex. 1059, 3.

14 Bock, S., et al., “Solutions of Gallium Trichloride in Ethers,” Z.
Naturforsch. 45b:979–984 (1990).
15 Boardman, A., et al., “A Gallium(III) Halide Complex Containing 5-
Coordinate Gallium GaCl3-1,4-dioxane,” Inorganica Chimica Acta, 87
(1984).
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Boardman also does not support Petitioner’s argument because it does not
expressly address Et2O as a ligand, and further explains that whether GaCl3
pentacoordinates depends on the ligand. Ex. 1060; Ex. 2041, 149:13–19.
Accordingly, we are not persuaded that Petitioner presents sufficient
evidence that Gao discloses mixing its cation-ligand complex with an anion
precursor at a first temperature (which Petitioner contends is room
temperature) sufficient to induce reaction between them. Gao does not
expressly disclose inducing a reaction at room temperature, and Petitioner’s
contention rests on its showing that a person of ordinary skill in the art
would have understood that “the strong coordinating ability between GaCl3
and Na3P would cause the formation of a Lewis acid-base adduct, even at
room temperature.” Pet. 59–60 (citing Ex. 1003 ¶ 272). The Wells
publications (Exs. 1020, 1029) on which Petitioner relies, however, describe
different reactants, solvents, and conditions than Gao, and Petitioner does
not explain in light of those differences how a person of ordinary skill in the
art would have applied any teaching from the Wells publications to Gao.
Therefore, we determine Petitioner has not carried its burden to
demonstrate by a preponderance of the evidence that Gao discloses all of the
limitations required by claim 22.
Claim 23
Claim 23 depends from claim 22. Petitioner’s arguments with respect
to dependent claim 23 do not address the deficiency discussed above with
respect to claim 22. See Pet. 61.
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Conclusion
For the foregoing reasons, we conclude that Petitioner has not
demonstrated by a preponderance of the evidence that claims 22 and 23 are
anticipated by Gao.
K. Ground 8: Alleged Anticipation Based on Alivisatos
Petitioner contends that claims 22 and 23 are anticipated by
Alivisatos. Pet. 61–64.
Claim 22
a first temperature sufficient to induce reaction between the
cation-ligand complex and the anion precursor
As discussed in Ground 6 supra, Petitioner contends that a person of
ordinary skill in the art would have understood that in Alivisatos’s Example
6, GaCl3 was a cation precursor, tributylphosphine was a ligand, and high-
boiling petroleum distillate fraction was a non-coordinating solvent, and that
the GaCl3 and tributylphosphine form a cation-ligand complex because the
electron pairs of tributylphosphine bound to Ga. Pet. 62 (citing Ex. 1003 ¶
285). Petitioner further contends that Alivisatos discloses
tris(trimethylsilyl)arsine as an anion precursor that is mixed with the GaCl3-
tributylphosphine cation ligand complex to induce a reaction at room
temperature. Id. (citing Ex. 1003 ¶¶ 287–288). Petitioner contends a person
of ordinary skill in the art would have understood “that the combination of
GaCl3 (a Lewis acid) and tris(trimethylsilyl)arsine (a Lewis base) would
induce a reaction . . . because the strong coordinating ability between GaCl3
and tris(trimethylsilyl)arsine would cause the formation of a Lewis acid-base
adduct, even at room temperature.” Id. (citing Ex. 1003 ¶ 288).
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Patent Owner contends Alivisatos does not disclose that the anion
precursor and cation ligand complex were mixed “at a first temperature
sufficient to induce reaction” because Alivisatos does not state the
temperature at which the reagents were combined, and fails to state any sign
that a reaction was induced prior to heating. PO Resp. 63 (citing Ex. 1008,
5:29–33; Ex. 2001 ¶ 269). Patent Owner further contends, similarly as
discussed supra in Ground 7, that the Wells publications (Exs. 1020 and
1029) do not support Dr. Owen’s opinion that a reaction would occur at
room temperature, because they report different precursors and reaction
media from Alivisatos. Id. at 63–64 (citing Ex. 1003 ¶ 272; Ex. 2001 ¶¶
259–261).
Petitioner replies by arguing that Patent Owner points to “trivial
differences such as Wells 1997 using InCl3 and Alivisatos using GaCl3,
ignoring that In and Ga are both Group 13 elements.” Pet. Reply 23.
We are not persuaded that Petitioner presents sufficient evidence that
Alivisatos discloses mixing its cation-ligand complex with an anion
precursor at a first temperature (which Petitioner contends is room
temperature) sufficient to induce reaction between them. Alivisatos does not
expressly disclose inducing a reaction at room temperature. Further,
Alivisatos does not describe any indicia that a reaction occurred prior to
heating to 300 °C, such as a color change or formation of a precipitate. Ex.
1008, 5:19–33, 6:30–35, 44–46. In the absence of such evidence,
Petitioner’s contention rests on its showing that a person of ordinary skill in
the art would have understood that “the strong coordinating ability between
GaCl3 and tris(trimethylsilyl)arsine would cause the formation of a Lewis
acid-base adduct, even at room temperature.” Pet. 62 (citing Ex. 1003
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¶ 288). The Wells publications on which Dr. Owen relies, however,
describe different reactants, reaction media, and conditions than Alivisatos.
Ex. 1020, 9; Ex. 1029, 6. Petitioner’s argument that these differences are
“trivial” because In and Ga are both Group 13 elements is not persuasive,
because it does not address additional differences between the reactions,
such as temperature and reaction media. Dr. Owen acknowledged that such
differences are impactful. See Ex. 2041, 135:17–137:3 (discussing
disassociation of ligands in Tolman). In light of those differences, Petitioner
does not sufficiently explain how a person of ordinary skill in the art would
have applied teachings from the Wells publications to Alivisatos’s Example
6.
Therefore, we determine Petitioner has not carried its burden to
demonstrate by a preponderance of the evidence that Alivisatos discloses all
of the limitations required by claim 22.
Claim 23
Claim 23 depends from claim 22. Petitioner’s arguments with respect
to dependent claim 23 do not address the deficiency discussed above with
respect to claim 22. See Pet. 64.
Conclusion
For the foregoing reasons, we conclude that Petitioner has not
demonstrated by a preponderance of the evidence that claims 22 and 23 are
anticipated by Alivisatos.
IV. CONCLUSION
Based on the arguments and evidence presented by the parties during
this entire proceeding, we determine that Petitioner has failed to establish, by
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a preponderance of the evidence, that claims 1–11 and 13–23 of the ’051
patent are unpatentable.
V. ORDER
In consideration of the foregoing, it is hereby:
ORDERED that Petitioner has not shown by a preponderance of the
evidence that claims 1–11 and 13–23 of the ’051 Patent are unpatentable.
FURTHER ORDERED that, because this is a Final Written Decision,
parties to the proceeding seeking judicial review of the decision must
comply with the notice and service requirements of 37 C.F.R. § 90.2.

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In summary:

Claims

35
U.S.C.
§
Reference(s)/Basis Claims
Shown
Unpatentable
Claims
Not shown
Unpatentable
1–9, 11,
14, 21
102(b) Trentler 1–9, 11, 14,
21
10 103 Trentler, Aldrich
Catalog
10
2, 3, 15–18 103 Trentler, Murray
1993
2, 3, 15–18
13 103 Trentler 13
4, 19, 20 103 Trentler, Alivisatos 4, 19, 20
1–9, 11,
13, 14, 19–
21
103 Alivisatos, Trentler 1–9, 11, 13,
14, 19–21
22, 23 102(b) Gao 22, 23
22, 23 102(b) Alivisatos 22, 23
Overall
Outcome
1–11, 13–23
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PETITIONER:

Bryon Pickard
Bpickard-ptab@sternekessler.com

David Holman
Dholman-ptab@sternekessler.com

PATENT OWNER:

Maximilienne Giannelli
Maximilienne.giannelli@finnegan.com

Joshua Goldberg
Joshua.goldberg@finnegan.com