NOTE: This disposition is nonprecedential.

 

United States Court of Appeals 

for the Federal Circuit ______________________ 

CORNELL RESEARCH FOUNDATION, INC.,

Appellant

v.

KATHERINE K. VIDAL, UNDER SECRETARY OF 

COMMERCE FOR INTELLECTUAL PROPERTY 

AND DIRECTOR OF THE UNITED STATES 

PATENT AND TRADEMARK OFFICE,

Intervenor

______________________ 

2020-2334, 2020-2335, 2020-2337, 2020-2338, 2020-2339, 

2020-2340

______________________ 

Appeals from the United States Patent and Trademark 

Office, Patent Trial and Appeal Board in Nos. IPR2019-

00577, IPR2019-00578, IPR2019-00579, IPR2019-00580, 

IPR2019-00581, IPR2019-00582.

______________________ 

Decided: May 24, 2022

______________________ 

JULIE S. GOLDEMBERG, Morgan, Lewis & Bockius LLP, 

Philadelphia, PA, argued for appellant. Also represented 

by ROBERT CHRISTIAN BERTIN, ROBERT JOHN SMYTH, Washington, DC; AJIT VAIDYA, Kenealy Vaidya LLP, Washington, DC. 

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2 CORNELL RESEARCH FOUNDATION, INC. v. VIDAL

 MAUREEN DONOVAN QUELER, Office of the Solicitor, 

United States Patent and Trademark Office, Alexandria, 

VA, argued for intervenor. Also represented by MICHAEL 

S. FORMAN, THOMAS W. KRAUSE, AMY J. NELSON, FARHEENA 

YASMEEN RASHEED. 

 ______________________ 

Before PROST, REYNA, and TARANTO, Circuit Judges.

PROST, Circuit Judge. 

Cornell Research Foundation, Inc. (“Cornell”) appeals 

from six inter partes reviews (“IPR”), each regarding a different Cornell patent, in which the Patent Trial and Appeal 

Board (“Board”) concluded that the challenged claims were 

unpatentable as anticipated or obvious. E.g., Associated 

British Foods PLC v. Cornell Rsch. Found., Inc., 

No. IPR2019-00577, Paper 117 (P.T.A.B. July 23, 2020) 

(“Final Written Decision”). Because substantial evidence 

supports the Board’s determinations that the claims were 

obvious, we affirm.

BACKGROUND

I 

The patents at issue relate to phytases in livestock 

feed. Phytases are enzymes that help certain animals absorb phosphate, an important nutrient. Skilled artisans 

can produce phytase enzymes by taking a phytase gene 

from one organism and incorporating it into a host; the host

then replicates and expresses the phytase protein, which 

can then be added to the feed. 

U.S. Patent No. 8,993,300 (“the ’300 patent”), representative in this appeal, describes a heterologous method 

of producing phytase: it uses a phytase gene derived from 

Escherichia coli, a species of bacteria, and a fungal host. 

There are different strains of E. coli, and different strains 

express different phytases. Two are relevant here: E. coli

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CORNELL RESEARCH FOUNDATION, INC. v. VIDAL 3

appA phytase and E. coli B phytase. There are also a variety of fungal species. As is relevant here, the fungal kingdom includes yeast, of which Saccharomyces cerevisiae and 

Pichia pastoris are species. 

Independent claim 1 and dependent claims 10–12 of 

the ’300 patent are representative for the purposes of this 

consolidated appeal. They recite:

1. A method of producing a phytase in fungal cells, 

the method comprising:

providing a polynucleotide encoding an Escherichia 

coli phytase;

expressing the polynucleotide in the fungal cells; 

and

isolating the expressed Escherichia coli phytase 

wherein the Escherichia coli phytase catalyzes the 

release of phosphate from phytate.

10. The method of claim 1 wherein the Escherichia 

coli phytase has an optimum activity at a temperature range of 57 degrees C. to 65 degrees C.

11. The method of claim 1 wherein the Escherichia 

coli phytase retains at least 40% of its activity after 

heating the phytase for 15 minutes at 80 degrees 

C.

12. The method of claim 1 wherein the Escherichia 

coli phytase retains at least 60% of its activity after 

heating the phytase for 15 minutes at 60 degrees 

C.

Dependent claims 10–12 add so-called “thermostability 

limitations” to the phytases produced by the heterologous 

method described in independent claim 1.

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4 CORNELL RESEARCH FOUNDATION, INC. v. VIDAL

II

We recount only the relevant procedural history below. 

Associated British Foods PLC (“ABF”) filed six IPR petitions, each challenging a different Cornell patent. The 

Board instituted review for all six and found all challenged 

claims unpatentable. 

ABF asserted two varieties of prior-art combinations in 

its petitions—those involving Kretz1 and those not involving Kretz. The Kretz-based challenges apply only to 

the ’300 patent. But the parties agree that all six Board 

decisions “stand and fall” with the Board’s non-Kretz obviousness analysis for the ’300 patent. Reply Br. 26–27. We

accordingly focus our discussion on the Board’s Final Written Decision for the ’300 patent. 

Beginning with the non-Kretz grounds, ABF asserted 

that all challenged claims of the ’300 patent would have 

been obvious over two combinations: (1) Dassa,2 Greiner,3

and Cheng4 and (2) Dassa, Greiner, Romanos,5 and 

Van Gorcom6 (collectively, “the Dassa/Greiner 

1 U.S. Patent No. 5,876,997 (“Kretz”).

2 Janie Dassa, Christian Marck, & Paul L. Boquet, 

The Complete Nucleotide Sequence of the Escherichia coli

Gene appA Reveals Significant Homology Between pH 2.5 

Acid Phosphatase and Glucose-1-Phosphatase, 

172 J. BACTERIOLOGY 5497 (1990) (“Dassa”).

3 R. Greiner, U. Konietzny, & Kl.-D. Jany, Purification and Characterization of Two Phytases from Escherichia coli, 303 ARCHIVES BIOCHEMISTRY & BIOPHYSICS 107

(1993) (“Greiner”).

4 U.S. Patent No. 5,985,605 (“Cheng”).

5 Michael A. Romanos, Carol A. Scorer, & Jeffrey J. 

Clare, Foreign Gene Expression in Yeast: A Review, 8 YEAST

423 (1992) (“Romanos”).

6 U.S. Patent No. 5,436,156 (“Van Gorcom”).

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CORNELL RESEARCH FOUNDATION, INC. v. VIDAL 5

combinations”). ABF argued that the thermostability

claims of the ’300 patent would have been obvious for two 

independent reasons: (1) they were inherent properties of 

the Dassa/Greiner combinations, and (2) they were disclosed by Olsen.7 In its Final Written Decision, the Board 

concluded that there was a motivation to combine and reasonable expectation of success for the Dassa/Greiner combinations and that the thermostability dependent claims of 

the ’300 patent were obvious due to inherency. See Final 

Written Decision, at 127–31, 141, 172–73. 

For the Kretz-based invalidity arguments, ABF asserted that Kretz (1) anticipated certain challenged claims 

of the ’300 patent as § 102(e) prior art8 and (2) rendered all 

challenged claims obvious in combination with other references. See id. at 10–11. The Board determined that Cornell failed to antedate Kretz, id. at 34, and that Kretz 

anticipated certain claims and rendered obvious the rest in 

light of those other references, see id. at 172–73. 

Cornell appeals from all six final written decisions in 

this consolidated appeal. The Patent and Trademark Office Director intervened to defend the Board’s decisions after ABF filed a notice of non-participation. We have 

jurisdiction under 28 U.S.C. § 1295(a)(4)(A). 

DISCUSSION

Cornell asserts primarily that three Board conclusions 

lack substantial evidence: (1) that there was a motivation 

to combine and reasonable expectation of success for the 

Dassa/Greiner combinations; (2) that the thermostability 

properties of the phytases produced by the claimed heterologous method are inherent; and (3) that Cornell failed to 

7 Ole Olsen & Karl Kristian Thomsen, Improvement 

of Bacterial β-Glucanase Thermostability by Glycosylation, 

137 J. GEN. MICROBIOLOGY 579 (1991) (“Olsen”).

8 35 U.S.C. § 102(e) (2010).

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6 CORNELL RESEARCH FOUNDATION, INC. v. VIDAL

antedate Kretz. We affirm the Board on the first two issues 

and accordingly do not reach the third.

I 

Putting aside the thermostability limitations of the 

’300 patent’s dependent claims (discussed below), Cornell 

does not dispute that the Dassa/Greiner combinations disclose all limitations of the relevant claims. Cornell disputes only the Board’s findings of motivation to combine 

and reasonable expectation of success for an E. coli phytase 

with a fungal host. Those are both fact questions that we 

review for substantial evidence, which is “such relevant evidence as a reasonable mind might accept as adequate to 

support a conclusion.” In re Mouttet, 686 F.3d 1322, 1331 

(Fed. Cir. 2012); PAR Pharm., Inc. v. TWI Pharms., Inc., 

773 F.3d 1186, 1196 (Fed. Cir. 2014).

In finding a motivation to combine, the Board credited 

ABF’s expert testimony that P. pastoris yeast was known 

to “produce high yields of heterologous protein [e.g., bacterial protein] and, thus, reduce industrial costs—an important factor in producing phytases for livestock feed” on 

an industrial level. Final Written Decision, at 128. The 

Board found this to be “persuasive evidence setting forth

reasons why [a] skilled artisan would have been motivated 

to express an E. coli appA [enzyme] in a fungal cell.” Id. 

This constitutes substantial evidence for a motivation to 

combine. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 420 

(2007) (“[A]ny need or problem known in the field of endeavor at the time of invention and addressed by the patent 

can provide a reason for combining the elements in the 

manner claimed.”).

Cornell’s two main arguments to the contrary are unpersuasive. First, Cornell asserts that the Board’s motivation-to-combine conclusion is contrary to ABF’s expert 

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CORNELL RESEARCH FOUNDATION, INC. v. VIDAL 7

testimony that the Wodzinski reference9 taught away from 

using a bacterial phytase in animal feed. We note that 

Wodzinski is not a part of the Dassa/Greiner combinations;

additionally, the Board did not make any determination as

to whether Wodzinski does or does not teach away. Final

Written Decision, at 84. And even if the Board concluded 

that Wodzinski’s suggestions about bacterial phytases in 

animal feed, generally, were outweighed by the rest of the 

record evidence about producing E. coli appA phytase via a 

fungal host for use in animal feed, specifically, we would 

see no error. See In re Young, 927 F.2d 588, 591 (Fed. Cir. 

1991).

Second, Cornell contends that the art suggested that 

pairing a bacterial phytase with a bacterial host was more 

advantageous than pairing such a phytase with a fungal 

host. Even if that’s true, as the Board correctly noted, “the 

law ‘does not require that the motivation be the best option, 

only that it be a suitable option.’” Final Written Decision, 

at 81–82 (emphasis omitted in original) (quoting PAR 

Pharm., 773 F.3d at 1197–98). 

Cornell’s challenge to the substantial evidence of the 

Board’s reasonable-expectation-of-success finding is similarly flawed. Cornell asserts a skilled artisan would have 

“had no reason to expect ‘that expressing the E. coli

phytase in a fungal host would have produced an active enzyme’” due to increased glycosylation, as its expert testified. Appellant’s Br. 33 (quoting J.A. 4084–89). Cornell’s 

expert provided two examples of unsuccessful heterologous 

systems “where one of ordinary skill . . . may have attributed the lack of enzyme activity to glycosylation.” Final Written Decision, at 90. But the Board was free to 

weigh ABF’s expert testimony more heavily, and that’s 

what it did. The Board credited ABF’s expert testimony 

providing “nine or ten” contrary examples of systems that 

9 See J.A. 22462–63; see also J.A. 15187–89. 

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8 CORNELL RESEARCH FOUNDATION, INC. v. VIDAL

produced active bacterial enzymes in yeast hosts. Id.

at 90–91. In addition, the Board pointed to Cornell’s expert 

testimony that, “in the majority of cases[,] glycosylation did 

not have an effect on the activity of the enzyme.” Id.

at 91–92.

We accordingly affirm the Board’s determination that 

there was a motivation to combine and reasonable expectation of success for the Dassa/Greiner combinations.10

II

Cornell also challenges the Board’s finding that the 

thermostability limitations in the ’300 patent’s dependent 

claims are inherent results of the Dassa/Greiner combinations. Whether prior art inherently discloses a claim limitation is a question of fact that we review for substantial 

evidence. PAR Pharm., 773 F.3d at 1194. 

The Board found the thermostability limitations inherent to a heterologous system expressing the Dassa/Greiner 

E. coli appA phytase in a fungal host disclosed by Cheng, 

Romanos, or Van Gorcom, including P. pastoris and S. cerevisiae. The Board cited Cornell’s expert testimony, ABF’s 

expert testimony, the ’300 patent, and prosecution history 

as support. Final Written Decision, at 78–79. Indeed, the 

Board credited Cornell’s expert, who confirmed that “express[ing] the same enzyme in the same host under the 

same conditions” produces “inherent results,” like thermostability characteristics. J.A. 7694–95 (emphasis added); 

Final Written Decision, at 78 (citing J.A. 7695). This constitutes substantial evidence supporting the Board’s determination. 

10 We are not persuaded by Cornell’s contention that 

the Board’s analysis of the non-Kretz combinations is infected by analysis of Kretz.

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CORNELL RESEARCH FOUNDATION, INC. v. VIDAL 9

Cornell’s two arguments to the contrary are not persuasive. First, Cornell faults the Board for citing no data 

outside of the ’300 patent to support its inherency finding. 

But the Board permissibly cited the ’300 patent’s disclosure that an E. coli appA phytase expressed in a P. pastoris

host has optimum activity at 60 degrees Celsius as well as 

the patent’s teaching that an E. coli appA phytase expressed in a S. cerevisiae host retained 69 percent of its activity after heating it for 15 minutes at 80 degrees Celsius. 

Final Written Decision, at 78–79; see Hospira, Inc. v. Fresenius Kabi USA, LLC, 946 F.3d 1322, 1329–30 (Fed. Cir. 

2020). That data is consistent with the thermostability 

limitations of claims 10–12. Although it may be possible 

that the conditions of the Dassa/Greiner combinations 

were not the same as those described in the ’300 patent, 

Cornell did not make that argument and offered no evidence to that effect. Oral Arg. at 26:27–27:10, No. 20-2334, 

https://oralarguments.cafc.uscourts.gov/default.aspx?fl=20

-2334_05032022.mp3. 

Second, Cornell asserts that the Board’s inherency 

finding for the Dassa/Greiner combinations is at odds with 

its finding of no inherency with respect to Kretz as anticipatory art. Cornell argues that this is especially concerning because the standard for inherency under § 103 is 

higher than that under § 102. In this case, we find no error. 

The Board explained that it did not find the thermostability limitations inherent under Kretz because ABF was relying on Kretz’s teachings using the E. coli B phytase 

whereas the thermostability data from the ’300 patent resulted from using the E. coli appA phytase. Final Written 

Decision, at 58. This is consistent with the Board’s reliance 

on Cornell’s expert testimony that the same enzyme is

needed for the thermostability characteristics of an enzyme 

produced by a particular enzyme-host combination to be inherent. 

We thus also affirm the Board’s inherency finding as 

supported by substantial evidence. Since that resolves this 

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10 CORNELL RESEARCH FOUNDATION, INC. v. VIDAL

appeal as to all patents and all claims, we do not reach Cornell’s other arguments, including those about antedating

Kretz. 

CONCLUSION

We have considered the parties’ remaining arguments 

but find them unpersuasive. For the foregoing reasons, we 

affirm the Board’s obviousness conclusions. 

AFFIRMED 

COSTS

Costs to Intervenor. 

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