Source: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-16-02231/USCOURTS-ca13-16-02231-0/pdf.json

Nature of Suit Code: 830
Nature of Suit: Patent
Cause of Action: 

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United States Court of Appeals 

for the Federal Circuit ______________________

GS CLEANTECH CORPORATION,

Plaintiff-Appellant

v.

ADKINS ENERGY LLC,

Defendant-Cross-Appellant

______________________

2016-2231, 2017-1838

______________________

Appeals from the United States District Court for the 

Northern District of Illinois in No. 1:10-cv-04391, Judge 

Larry J. McKinney.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

GS CLEANTECH CORPORATION, GREENSHIFT 

CORPORATION,

Plaintiffs-Appellants

CANTOR COLBURN LLP

Interested Party

v.

BIG RIVER RESOURCES GALVA, LLC, BIG RIVER 

RESOURCES WEST BURLINGTON, LLC, 

LINCOLNLAND AGRI-ENERGY, LLC, IROQUOIS 

BIO-ENERGY COMPANY, LLC, CARDINAL 

ETHANOL, LLC, LINCOLNWAY ENERGY, LLC, 

Case: 16-2231 Document: 164 Page: 1 Filed: 03/02/2020
2 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

ICM, INC., BUSHMILLS ETHANOL, INC., AL-CORN 

CLEAN FUEL, LLC, CHIPPEWA VALLEY 

ETHANOL COMPANY, LLP, HEARTLAND CORN 

PRODUCTS, GEA MECHANICAL EQUIPMENTUS, 

INC., AS SUCCESSOR-IN-INTEREST TO GEA 

WESTFALIA SEPARATOR, INC. PURSUANT TO 

THE NOTICE OF MERGER FILED ON 4/28/2011,

ACE ETHANOL, LLC, BLUE FLINT ETHANOL LLC, 

UNITED WISCONSIN GRAIN PRODUCERS, LLC, 

FLOTTWEG SEPARATION TECHNOLOGY, INC., 

ADKINS ENERGY LLC, AEMETIS, INC., AEMETIS 

ADVANCED FUELS KEYES, INC., LITTLE SIOUX

CORN PROCESSORS, LLLP, GUARDIAN ENERGY, 

LLC, WESTERN NEW YORK ENERGY, LLC, 

SOUTHWEST IOWA RENEWABLE ENERGY, LLC, 

PACIFIC ETHANOL MAGIC VALLEY LLC, 

PACIFIC ETHANOL STOCKTON, HOMELAND 

ENERGY SOLUTIONS, LLC, PACIFIC ETHANOL, 

INC., DAVID J. VANDER GRIEND,

Defendants-Appellees

______________________

2017-1832

______________________

Appeal from the United States District Court for the 

Southern District of Indiana in Nos. 1:10-cv-00180-RLMDML, 1:10-cv-08000-RLM-DML, 1:10-cv-08001-RLMDML, 1:10-cv-08002-RLM-DML, 1:10-cv-08003-RLMDML, 1:10-cv-08004-RLM-DML, 1:10-cv-08005-RLMDML, 1:10-cv-08006-RLM-DML, 1:10-cv-08007-RLMDML, 1:10-cv-08008-RLM-DML, 1:10-cv-08009-RLMDML, 1:10-cv-08010-RLM-DML, 1:10-cv-08011-RLMDML, 1:10-ml-02181-RLM-DML, 1:13-cv-08012-RLMDML, 1:13-cv-08013-RLM-DML, 1:13-cv-08014-RLMDML, 1:13-cv-08015-RLM-DML, 1:13-cv-08016-RLMDML, 1:13-cv-08017-RLM-DML, 1:13-cv-08018-RLMCase: 16-2231 Document: 164 Page: 2 Filed: 03/02/2020
GS CLEANTECH CORP. v. ADKINS ENERGY LLC 3

DML, 1:14-cv-08019-RLM-DML, 1:14-cv-08020-RLMDML, Judge Larry J. McKinney.

______________________

Decided: March 2, 2020

______________________

STEVEN B. POKOTILOW, Stroock & Stroock & Lavan 

LLP, New York, NY, argued for plaintiffs-appellants. Also 

represented by BINNI N. SHAH.

 JOHN M. WEYRAUCH, Dicke, Billig & Czaja, PLLC, Minneapolis, MN, argued for defendants-appellees Big River 

Resources Galva, LLC, Big River Resources West Burlington, LLC, Lincolnland Agri-Energy, LLC, Cardinal Ethanol, LLC, Lincolnway Energy, LLC, ICM, Inc., Flottweg 

Separation Technology, Inc., Blue Flint Ethanol, LLC, David J. Vander Griend. Defendants-appellees Big River Resources Galva, LLC, Big River Resources West Burlington, 

LLC, Lincolnland Agri-Energy, LLC, Cardinal Ethanol, 

LLC, ICM, Inc., Flottweg Separation Technology, Inc., Little Sioux Corn Processors, LLLP, Guardian Energy, LLC, 

Western New York Energy, LLC, Southwest Iowa Renewable Energy, LLC, Pacific Ethanol Magic Valley LLC, David J. Vander Griend also represented by PETER R.

FORREST. 

 MICHAEL BUCHANAN, Patterson Belknap Webb & Tyler 

LLP, New York, NY, argued for defendants-appellees ACE 

Ethanol, LLC, Aemetis Advanced Fuels Keyes, Inc., 

Aemetis, Inc., Al-Corn Clean Fuel, LLC, Big River Resources Galva, LLC, Big River Resources West Burlington, 

LLC, Blue Flint Ethanol LLC, Bushmills Ethanol, Inc., 

Cardinal Ethanol, LLC, Chippewa Valley Ethanol Company, LLP, Flottweg Separation Technology, Inc., GEA Mechanical Equipment US, Inc., Guardian Energy, LLC, 

Heartland Corn Products, Homeland Energy Solutions, 

LLC, ICM, Inc., Iroquois Bio-Energy Company, LLC, 

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4 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

Lincolnland Agri-Energy, LLC, Lincolnway Energy, LLC, 

Little Sioux Corn Processors, LLLP, Pacific Ethanol Magic 

Valley LLC, Pacific Ethanol Stockton, Pacific Ethanol, Inc., 

Southwest Iowa Renewable Energy, LLC, United Wisconsin Grain Producers, LLC, David J. Vander Griend, Western New York Energy, LLC, Adkins Energy LLC. 

 KEITH DAVID PARR, Locke Lord LLP, Chicago, IL, for 

defendant-cross-appellant. Also represented by HUGH S.

BALSAM, WASIM K. BLEIBEL, JAMES THOMAS PETERKA. 

 SPIRO BEREVESKOS, Woodard Emhardt Henry Reeves & 

Wagner, LLP, Indianapolis, IN, for defendant-appellee Iroquois Bio-Energy Company, LLC. Also represented by 

DANIEL JAMES LUEDERS, LISA A. HIDAY. 

 GLENN JOHNSON, McKee, Voorhees & Sease, P.L.C., 

Des Moines, IA, for defendant-appellee Lincolnway Energy, LLC. 

 JOHN DONALD BEST, Michael Best & Friedrich, LLP, 

Madison, WI, for defendants-appellees Bushmills Ethanol, 

Inc., Chippewa Valley Ethanol Company, LLP, Heartland 

Corn Products, United Wisconsin Grain Producers, LLC. 

Also represented by KENNETH M. ALBRIDGE, III, JOHN C.

SCHELLER. 

 MARC ANDRE AL, Stoel Rives LLP, Minneapolis, MN, 

for defendant-appellee Al-Corn Clean Fuel, LLC. 

 RUTH RIVARD, Stinson LLP, Minneapolis, MN, for defendant-appellee Blue Flint Ethanol LLC. 

 CAMILLE L. URBAN, Brown, Winick, Graves, Gross, Baskerville & Schoenebaum, PLC, Des Moines, IA, for defendants-appellees Aemetis, Inc., Aemetis Advanced Fuels 

Keyes, Inc., Pacific Ethanol Stockton, Homeland Energy 

Case: 16-2231 Document: 164 Page: 4 Filed: 03/02/2020
GS CLEANTECH CORP. v. ADKINS ENERGY LLC 5

Solutions, LLC, Pacific Ethanol, Inc. Also represented by 

MICHAEL A. DEE. 

 ______________________

Before REYNA, WALLACH, and HUGHES, Circuit Judges.

WALLACH, Circuit Judge.

The U.S. District Court for the Southern District of Indiana (“District Court”) found Appellants GS CleanTech 

Corporation and Greenshift Corporation’s (together, 

“CleanTech”) U.S. Patent Nos. 7,601,858 (“the ’858 patent”), 8,008,516 (“the ’516 patent”), 8,008,517 (“the ’517 

patent”), and 8,283,484 (“the ’484 patent”) (together, “the 

Patents-in-Suit”) unenforceable due to inequitable conduct. Corrected Memorandum Opinion & Order after

Bench Trial, In re: Method of Processing Ethanol Byproducts & Related Subsystems (’858) Patent Litig., No. 1:10-

ml-02181-LJM-DML (S.D. Ind. Sept. 15, 2016), ECF 

No. 1653 (J.A. 236–313) (Opinion and Order); see J.A. 314–

15 (Judgment).

CleanTech appeals. We have jurisdiction pursuant to 

28 U.S.C. § 1295(a)(1) (2012). We affirm. 

BACKGROUND

I. The Patents-in-Suit1

The Patents-in-Suit are directed to the recovery of oil 

from a dry mill ethanol plant’s byproduct, called thin stillage. ’858 patent, Abstract.2 The Patents-in-Suit disclose

1 The Patents-in-Suit share a specification. For the 

ease of reference here, we will refer to the ’858 patent’s 

specification. 

2 Stillage treatment relates to the process of treating 

“‘whole stillage[,]’” which is the “waste stream comprised of 

byproducts” that is a result of the dry milling process. ’858 

patent col. 1 ll. 35–41. Dry milling is “a popular method of 

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6 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

a method of “successful” “recover[y] [of] the valuable oil 

from th[e] [thin stillage] byproduct,” id. col. 1 ll. 52–53, by, 

for example, “evaporating the thin stillage to form a concentrate,” id. col. 2 ll. 23–25, or syrup, and then “separating the oil from the concentrate using a disk stack 

centrifuge,” id. col. 2 ll. 25–27. 

Independent claim 8 of the ’858 patent recites:

A method of recovering oil from thin stillage, comprising, in sequence: evaporating the thin stillage to create 

a concentrate having a moisture content of greater

than 30% by weight and less than about 90% by 

weight; and centrifuging the concentrate to recover oil.

Id. col. 6 ll. 26–30.3 Independent claims 1, 10, and 16 include a separate post-evaporation heating step. Id. col. 5 

l. 65–col. 6 l. 7 (Independent Claim 1), col. 6 ll. 34–42 (Independent Claim 10), col. 6 ll. 59–64 (Independent 

Claim 16). All dependent claims recite various combinations of temperature, pH, or moisture content ranges for 

the syrup or the use of the centrifuge. Id. col. 6 ll. 8–33, 

43–58. Independent claim 30 of the ’484 patent similarly 

recites a “method of recovering oil from thin stillage[,]” except it is by “mechanically processing the thin stillage concentrate” instead of centrifugation. ’484 patent col. 8 

ll. 29–37.

producing ethanol . . . [and] is typically practiced using 

corn.” Id. col. 1 ll. 35–37. Whole stillage, which has commonly been treated as waste, “may be further separated 

into products known as distillers wet grains and ‘thin stillage.’” Id. col. 1 ll. 41–43. 

3 Independent claim 8, which is illustrative, broadly 

recites the claimed invention. The remaining claims recite 

additional limitations beyond those recited in independent 

claim 8. 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 7

Independent claim 1 of the ’516 patent provides the additional step of “evaporating water from the thin stillage to 

form a thin stillage concentrate.” ’516 patent col. 6 ll. 11–

19. Independent claim 7 includes the additional step of 

“separating distiller wet grains and thin stillage from the 

whole stillage” and using a disk stack centrifuge to separate the “oil from the thin stillage concentrate.” Id. col. 6 

ll. 34–42. Independent claim 1 of the ’517 patent also recites the creation of the thin stillage concentrate, within a 

broader moisture content range. ’517 patent col. 6 ll. 32–

37.

II. Factual History4

A. Development of the Ethanol Oil Recovery System

In 2000, David Cantrell founded Vortex Dehydration 

Technology (“VDT”), J.A. 117, with the purpose of selling 

products and methods of processing factory waste for resale, J.A. 118. In 2002, David Winsness joined VDT as its 

Chief Technology Officer. J.A. 117. Later in 2002, Messrs.

Cantrell and Winsness (collectively, “the Inventors”) met 

Greg Barlage, a “market unit manager for equipment 

sales” at the company Alfa Laval AB, which sold animal

and vegetable oil processing equipment. J.A. 117, 118. 

Mr. Barlage approached the Inventors with the proposal 

that VDT use Alfa Laval oil processing equipment—such 

as evaporators and centrifuges—in its processes. J.A. 119. 

Soon, the Inventors began developing an oil recovery product specifically designed for animal processing waste products, using centrifuges provided by Alfa Laval. J.A. 119.

Relevant here, VDT maintained a business relationship with Agri-Energy LLC (“Agri-Energy”), J.A. 121, 

which operated a dry-mill ethanol plant in Minnesota,

4 We will rely on the District Court’s factual recitation where it is uncontested by the parties. Where certain 

facts are disputed, we will refer to the record evidence. 

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J.A. 120.5 Starting sometime before June 2003, 

Mr. Cantrell shifted his focus from meat and fish byproduct 

processing to the creation of an ethanol oil recovery system

and hired employees from Alfa Laval and Agri-Energy, as 

well as a marketing team. J.A. 122. In June 2003, 

Mr. Cantrell sent an email to two Agri-Energy employees, 

including one named George Winter, that included information about how VDT’s oil recovery system for processed 

animal waste might be applicable in an ethanol plant, as 

well as an image of an oil recovery system with a centrifuge

and an operational cost spreadsheet. J.A. 123. Subsequently, Mr. Cantrell informed Mr. Barlage that Agri-Energy would send Mr. Barlage a sample of its “thin stillage 

5 The District Court discounted testimony provided 

by Mr. Cantrell at the bench trial, determining that 

Mr. Cantrell’s testimony “on any topic [to be] of little credible value.” J.A. 242. The District Court noted that 

Mr. Cantrell made “inconsistent statements,” “had some 

difficulty staying focused,” and “was argumentative and 

unclear about facts when questioned by [Appellees’] counsel.” J.A. 242–43. The District Court stated that this was 

in sharp contrast to Mr. Cantrell’s “fortuitously remember[ing] when events took place and recall[ing] the ‘real’ 

meaning of documents when questioned by CleanTech’s 

lawyers.” J.A. 243. The District Court concluded that 

“[Mr.] Cantrell’s testimony sounded carefully scripted rather than genuine and generally dismissive of the contemporaneous documentary evidence.” J.A. 243. Accordingly, 

the District Court determined that it would “rel[y] primarily on the documents and testimony from other witnesses 

about the relationship between Agri-Energy and inventors 

during this period[.]” J.A. 243. “[We] give[] great deference 

to the district court’s decisions regarding [the] credibility 

of witnesses.” Ecolochem, Inc. v. S. Cal. Edison Co., 227 

F.3d 1361, 1378–79 (Fed. Cir. 2000) (internal quotation 

marks and citation omitted). 

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and syrup” for oil recovery testing using a centrifuge. 

J.A. 124.6 

In June 2003, Mr. Barlage performed oil recovery tests

on the Agri-Energy samples by heating each sample to a 

temperature of 176 oF and running them through an Alfa 

Laval centrifuge. J.A. 125. The syrup had a pH of “approximately 4” and a “moisture content between 70% and 80%.” 

J.A. 125. Based on the tests, Mr. Barlage concluded that it 

was easier to divest oil from syrup than from thin stillage. 

J.A. 125. In his report (“June 2003 Report”), Mr. Barlage 

concluded that “[s]omething in the evaporation process allows for the product to breakdown to a level where the oil 

can be taken out easily[,]” and recommended additional 

testing at a plant. J.A. 110092. 

In early July 2003, Mr. Barlage traveled to Agri-Energy and tested VDT’s oil recovery system, including a centrifuge, with Agri-Energy’s ethanol syrup (“July 2003 

Test”). J.A. 128–29. Again, the test included a syrup with 

a pH of around 4, with a moisture content between 70% and 

80%, and the test was conducted at a temperature of 

180 oF. J.A. 128–29. During the test, the centrifuge separated the oil from the syrup, but the centrifuge repeatedly 

clogged. J.A. 129. Around this time, Mr. Winsness directed a VDT employee to prepare a drawing of the ethanol 

oil recovery system, J.A. 130–31, which was completed by 

the end of July 2003, J.A. 132; see J.A. 110044 (Ethanol Oil 

Recovery System Diagram). The employee understood that 

the Ethanol Oil Recovery System Diagram “was intended 

to become a sales drawing.” J.A. 17278. 

On August 1, 2003, Mr. Cantrell emailed several AgriEnergy employees (“August 2003 Email”) and attached a 

proposal, dated July 31, 2003. J.A. 132–33; see 

6 Ethanol syrup is concentrated thin stillage. 

J.A. 124.

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J.A. 110021–22 (“July 2003 Proposal”). The July 2003 Proposal stated that VDT “would like to offer Agri-Energy a 

No-Risk trial [of the] ‘Oil Recovery System.’” J.A. 110021. 

The proposal stated that “[t]he test module is designed to 

process 18,000 [pounds] per hour of evaporator condensate 

and recovers 16,000 [pounds] of oil per day adding annual 

profits of $312,000 to $530,000 per year.” J.A. 110021 (emphasis omitted). The proposal went on to detail the “NoRisk Trial,” which “allow[ed] Agri-Energy [sixty] days to 

operate the unit and confirm its value[,]” at which point 

Agri-Energy could “purchase the system” for $423,000 or 

“return the skid to [VDT] (no questions asked).” 

J.A. 110021 (emphasis omitted). According to the Inventors, the purpose of the letter was to seek an opportunity to 

run in-plant tests and obtain data on how the test module 

ran. J.A. 31418–19. Agri-Energy understood the July 

2003 Proposal as an offer for purchase. J.A. 248. 

On August 18, 2003, Mr. Cantrell traveled to Agri-Energy and, the following day, presented his proposal to the 

Agri-Energy Board of Directors. J.A. 135. In the meeting, 

Mr. Cantrell described VDT’s ethanol extraction system as 

“a process where the corn oil is pulled off[,]” and he asserted 

that the system “worked” and that it “would generate additional income[.]” J.A. 135–36. On the same day, Mr.

Winsness informed VDT shareholders that Mr. Cantrell 

was “meeting with an ethanol plant” and the Inventors “expect[ed] to have an order in the near future ($400K).” 

J.A. 136. On August 27, 2003, Mr. Cantrell informed 

VDT’s chairman that “‘we have made an offer to Agri-Energy.’” J.A. 136. Agri-Energy did not accept the July 2003 

Proposal, and no centrifuge system was installed at AgriEnergy’s facility at that time. J.A. 137; see J.A. 70656 (Testimony by Mr. Cantrell) (stating that Agri-Energy did not 

accept the July 2003 Proposal). In early 2004, Agri-Energy 

and VDT again communicated regarding the installation of 

an oil recovery system, J.A. 137, and in May 2004, a centrifuge was installed in the Agri-Energy plant, J.A. 139. 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 11

B. Patent Prosecution History

In February 2004, the Inventors contacted attorney

Andrew Dorisio about preparing a patent application for, 

inter alia, their method of separating corn oil from concentrated thin stillage using a centrifuge. J.A. 251–52. Specifically, the Inventors sought to patent a method whereby 

“[a]n evaporator would be used to concentrate thin stillage”

to a syrup with “a moisture content between 60% and 85%,”

and the syrup would then be mechanically processed to 

separate out the oil, using a disk stack centrifuge. J.A. 251. 

The temperature and pH of the thin stillage—150 oF to 

212 oF and with a pH range from 3 to 6—would be the 

standard values of thin stillage in an ethanol plant.

J.A. 251. Mr. Dorisio informed the Inventors about the onsale bar of 35 U.S.C. § 102 (2000), which required that the 

claimed invention not be sold or offered for sale more than 

one year before the application filing date, and inquired if 

such an offer had been made. J.A. 252; see J.A. 111059; see 

also 35 U.S.C. § 102(b) (“A person shall be entitled to a patent unless . . . the invention was . . . on sale . . . more than 

one year prior to the date of the application for patent in 

the United States[.]”).7 Contemporaneous to their 

7 Congress amended 35 U.S.C. § 102 when it passed 

the Leahy-Smith America Invents Act (“AIA”), and AIA 

§ 4(e) made those changes applicable to “any patent application that is filed on or after” September 16, 2012. Pub. 

L. No. 112-29, § 4(e), 125 Stat. 284, 297 (2011). Because 

the application that led to the Patents-in-Suit was filed before September 16, 2012, pre-AIA § 102 applies. Under 

pre-AIA § 102, a person shall be entitled to a patent unless 

the claimed invention was on sale more than one year before the application’s filing date. 35 U.S.C. § 102(b). A patent is invalid under the on-sale bar if, before the filing

date, the invention was both (1) the subject of a commercial 

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discussion with Mr. Dorisio, the Inventors also conducted 

research on the U.S. Patent and Trademark Office’s

(“USPTO”) website, which included information about provisional patent applications and the on-sale bar. J.A. 252. 

Subsequently, the Inventors provided Mr. Dorisio with 

test results from June 2003 and described the July 2003 

Tests. J.A. 255. Mr. Dorisio, apparently without being told 

about the July 2003 Proposal or the Ethanol Oil Recovery

System Diagram, filed U.S. Provisional Patent Application

No. 60/602,050 (“the ’050 provisional application”) on August 17, 2004, with the USPTO, J.A. 140, 151; see J.A. 900,

setting the critical date for the on-sale bar at August 17, 

2003, J.A. 164. See Helsinn Healthcare S.A. v. Teva 

Pharm. USA, Inc., 855 F.3d 1356, 1360 (Fed. Cir. 2017)

(“The critical date for the on-sale bar is one year earlier[.]”), 

aff’d, 139 S. Ct. 628 (2019). In May 2005, Mr. Dorisio filed 

a non-provisional application, U.S. Patent Application 

No. 11/122,859 (“the ’859 application”). The’859 application included a letter stating that a separate patent application, entitled “Substantially Fat Free Products From 

Whole Stillage Resulting from the Production of Ethanol 

from Oil-Bearing Agricultural Products,” U.S. Patent Application No. 10/619,833 (“Prevost”), “may be found to claim 

the same invention as at least one claim of the instant application.” J.A. 256 (internal quotation marks omitted). 

In July 2005, Mr. Dorisio provided the Inventors with 

a draft clearance opinion, based on his understanding that 

the Inventors had reduced their claimed invention to practice in June 2003, and argued that the Inventors could 

swear behind Prevost, which was filed on July 15, 2003. 

J.A. 256; see J.A. 111060–74 (Draft Clearance Opinion); see

also J.A. 111065 (“Past correspondence indicates [the] actual reduction to practice of the [claimed invention] during 

sale or offer for sale and (2) “ready for patenting.” See Pfaff 

v. Wells Elecs., Inc., 525 U.S. 55, 67 (1998). 

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experiments conducted in early to mid-June 2003. If accurate, this date of invention precedes the filing date 

of . . . [Prevost] by at least one month[.]”), 18286 (Prevost)

(providing a filing date of July 15, 2003). In 2006, the Inventors joined CleanTech, J.A. 35686, which acquired 

VDT’s ethanol oil recovery method applications, J.A. 8–10.8 

In March 2008, Mr. Winsness transferred the prosecution of CleanTech’s ethanol oil recovery method applications from Mr. Dorisio to the law firm Cantor Colburn LLP

(“Cantor Colburn”). J.A. 257. An attorney at Cantor Colburn, Peter Hagerty, explained to at least one of the Inventors the on-sale bar and the Inventors’ obligation of candor 

toward the USPTO. J.A. 54666. In June 2008, a USPTO

patent examiner rejected the ’859 application, based in 

part on Prevost. J.A. 258. Cantor Colburn amended the 

’859 application’s claims. J.A. 258. By at least September 2008, Cantor Colburn was aware of Mr. Barlage’s testing in June and July 2003. J.A. 111075; see J.A. 111075 

(Mr. Winsness’s Email to Mr. Hagerty) (explaining that the 

“testing we did in June 2003” showed that “a sequence of 

evaporation followed by centrifugation allows for oil recovery”).

In May 2009, a potential investor in CleanTech conducted due diligence and sought information on the company’s pending patent applications; specifically, the 

potential investor requested from the Inventors “‘pre-filing 

disclosures of the inventions’” or “‘pre-filing offers for 

sale[,]’” among other information. J.A. 261; see 

J.A. 111023. The Inventors denied having any such 

8 The ’858 patent issued from the ’859 application, 

J.A. 900, and all the remaining patents of the Patents-inSuit issued from applications that were continuations of 

the ’859 application, J.A. 910, 921, 953. The Patents-inSuit claim effective filing dates of August 17, 2004. 

J.A. 900, 910, 921, 953. 

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information, although, in 2010, “Mr. Cantrell had retained 

a ‘signed version’ of the July 2003 Proposal in his ‘home 

files,’ and ‘an unsigned version was on [Mr.] Winsness’[s] 

computer[.]’” J.A. 262; see J.A. 63882. In June 2009, Cantor Colburn withdrew the pending ’859 application from issue. J.A. 264; see J.A. 71338. 

On the same day as the withdrawal, Cantor Colburn 

filed a letter with the USPTO in the ’859 application file

disclosing that “[s]ometime in May 2004, feasibility testing 

of a process and system for recovering oil from thin stillage 

was performed[.]” J.A. 110380. The letter was also filed 

with the USPTO in the prosecution of the ’516, ’517, and 

’484 patents. J.A. 264–65; see J.A. 110371–78, 110697–99. 

No reference was made to Mr. Barlage’s June and 

July 2003 testing, the June 2003 Report, the Ethanol Oil 

Recovery System Diagram, or the July 2003 Proposal. See 

generally J.A. 110371–74, 110375–78, 110379–81, 110697–

99. In October 2009, the USPTO issued the ’858 patent. 

J.A. 900. 

C. The Two Cantrell Declarations

In March 2010, Mr. Winsness provided a signed copy of 

the July 2003 Proposal to Cantor Colburn. J.A. 267; see 

J.A. 63882.9 Around June 2010, Mr. Hagerty drafted a 

9 At trial, evidence showed that Mr. Winsness provided Cantor Colburn with two letters in March 2010: an 

ink-signed original dated July 31, 2003, and an ink signed 

original dated August 19, 2003. J.A. 63882. The two letters differed from the electronic versions sent by 

Mr. Cantrell to Agri-Energy, such as by presenting a different letterhead. J.A. 266–67. The parties presented evidence about when each letter was signed, but the District 

Court “f[ound] the results of the experts’ analyses inconclusive with respect to the dating” of the two letters. J.A. 267. 

Additionally, the District Court concluded that “[i]f it had 

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two-page Information Disclosure Statement (“IDS”) to be 

submitted to the USPTO, attaching the July 2003 Proposal. J.A. 110793–95; see J.A. 270. In the IDS, Mr. 

Hagerty claimed that the ’858 patent’s method was “never 

disclosed, carried out, or performed” more than one year 

before the filing date and that the July 2003 Proposal was 

irrelevant. J.A. 110793–95. 

In May and June 2010, Mr. Winsness met with a company that stated that it had reason to believe the ’858 patent, as well as the other Patents-in-Suit, were invalid due 

to an offer in violation of the on-sale bar. J.A. 268. In late 

June 2010, Mr. Winsness made an “unannounced” trip to 

Agri-Energy and offered to provide Agri-Energy with a royalty-free license for CleanTech’s ethanol oil recovery system, which Agri-Energy refused. J.A. 146–47. AgriEnergy’s maintenance manager testified that he felt that 

Mr. Winsness was offering “a royalty-free license in exchange for admitting the patent was valid.” J.A. 146. 

Mr. Winsness testified that he had offered a royalty-free 

system to Agri-Energy in 2004 and an “early adopter advantage” at an unspecified point in time. J.A. 269. Subsequently, in July 2010, Cantor Colburn attorney Michael 

Rye provided Agri-Energy with a letter, asking Agri-Energy to “confirm” certain facts, including that VDT had not 

provided Agri-Energy with drawings or diagrams “for the 

not questioned [Mr.] Winsness’[s] veracity on other issues, 

the [District] Court could certainly conclude from this that 

[Mr.] Winsness has a propensity to evade the truth.” 

J.A. 266. For the purposes of our analysis, this point is ancillary—albeit concerning regarding the candor of counsel 

and their clients—to the significant fact that Mr. Cantrell 

provided Agri-Energy with a version of the July 2003 Proposal by email on August 1, 2003, a fact that is now not 

disputed. J.A. 155; see J.A. 110274 (Second Cantrell Declaration). 

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16 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

proposed system in 2003” and that the system proposed to 

Agri-Energy was for testing purposes. J.A. 147; see

J.A. 110322–23. Agri-Energy refused to verify the assertions, as it believed most of them to be “untrue.” J.A. 148. 

Soon after, Mr. Cantrell claimed to Cantor Colburn that he 

hand-delivered the July 2003 Proposal to Agri-Energy on 

August 18, 2003, despite the letter bearing a date weeks 

earlier. J.A. 148; see J.A. 70601. 

In November 2010, Cantor Colburn filed a declaration

executed by Mr. Cantrell with the USPTO for the ’516 and 

’517 patent applications and attached a copy of the 

July 2003 Proposal. The declaration explained that Mr.

Cantrell had hand delivered the July 2003 Proposal to 

Agri-Energy on August 18, 2003. J.A. 148; see J.A. 110016–

19 (First Cantrell Declaration). Cantor Colburn informed 

the USPTO that the July 2003 Proposal did not violate the 

on-sale bar, as it occurred less than a year before the application filing date. J.A. 148. Omitted from the disclosure 

was Mr. Barlage’s Test Report, the Ethanol Oil Recovery

System Diagram, and Mr. Barlage’s June and July 2003 

testing. See generally J.A. 110016–19. The USPTO issued 

the ’516 and ’517 patents on August 30, 2011. See J.A. 910, 

921. 

In September 2011, Mr. Cantrell was deposed regarding the infringement lawsuit of the instant case. J.A. 148; 

see J.A. 20185–249. Mr. Cantrell was shown the July 2003

Proposal emailed to Agri-Energy on August 1, 2003, and 

Mr. Cantrell testified that the email was not authentic. 

J.A. 278; see J.A. 20207–08. Mr. Cantrell later admitted 

that it was “possible” that he sent the August 1 email. 

J.A. 70601. Mr. Hagerty, when deposed in 2011, stated 

that “‘it sent a chill up his spine’” when he learned that the 

letter was sent on August 1, 2003. J.A. 278. The parties, 

however, had stipulated during the March to August 2010 

timeframe that Cantor Colburn was working under the impression that the July 2003 Proposal was sent on or near 

August 1, 2003. J.A. 278–79. Mr. Hagerty testified that he 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 17

was unconcerned about the July 2003 Proposal because it 

did not “disclose anything or amount to an offer.” J.A. 279. 

In July 2012, Cantor Colburn withdrew the ’484 patent 

application, which also contained the First Cantrell Declaration, and filed a second declaration from Mr. Cantrell

with the USPTO, which stated that Mr. Cantrell had forgotten about sending the August 2003 Email with the 

July 2003 Proposal attached. J.A. 155, see J.A. 110274

(Second Cantrell Declaration). Notably, the Second 

Cantrell Declaration did not provide any retractions of the 

false information provided in the First Cantrell Declaration—that it misstated that the first delivery of the 

July 2003 Proposal was on August 18, 2003—and did not 

explain the significance of the email in the Second Cantrell 

Declaration, which indicated a pre-critical date offer for 

sale. See generally J.A. 110274. In October 2012, the ’484 

patent issued. J.A. 953. 

III. Procedural History

Starting in 2009 and continuing through 2014, CleanTech filed lawsuits against the Appellees10 and Adkins 

10 The Appellees are: Big River Resources Galva, 

LLC; Big River Resources West Burlington, LLC; Lincolnland Agri-Energy, LLC; Iroquois Bio-Energy Company, 

LLC; Cardinal Ethanol, LLC; Lincolnway Energy, LLC;

ICM, Inc.; Bushmills Ethanol, Inc.; Al-Corn Clean Fuel, 

LLC; Chippewa Valley Ethanol Company, LLP; Heartland 

Corn Products; GEA Mechanical Equipment US, Inc., as 

Successor-in-Interest to GEA Westfalia Separator, Inc.;

Ace Ethanol, LLC; Blue Flint Ethanol, LLC; United Wisconsin Grain Producers, LLC; Flottweg Separation Technologies, Inc.; Aemetis, Inc.; Aemetis Advanced Fuels 

Keyes, Inc.; Little Sioux Corn Processors, LLLP; Guardian 

Energy, LLC; Western New York Energy, LLC; Southwest 

Iowa Renewable Energy, LLC; Pacific Ethanol Magic 

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18 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

Energy, LLC (“Adkins”) for infringement of the Patents-inSuit and CleanTech’s U.S. Patent No. 8,168,037 (“the ’037 

patent”) in a number of actions that were subsequently 

combined into a multidistrict litigation case. In 2013, 

CleanTech moved for summary judgment. J.A. 1, 4–5. The 

Appellees and Adkins moved for, inter alia, summary judgment on invalidity. J.A. 3–5. The District Court found 

there was no infringement. J.A. 83, 86–87, 88, 90–91, 96. 

The District Court determined that specified claims in the 

lawsuit were invalid because of the on-sale bar, J.A. 174; 

anticipation, J.A. 181; obviousness, J.A. 192, 217; incorrect 

inventorship, J.A. 202; inadequate written description, 

J.A. 195; lack of enablement, J.A. 197, 219; and indefiniteness, J.A. 205.11

Relevant here, the District Court determined that “undisputed contemporaneous evidence supports only one conclusion, the on-sale bar applies and invalidates the 

[Patents-in-Suit] because,” first, “the July [2003] Proposal 

was the culmination of a commercial offer for sale and,” 

second, “the method described in the [Patents-in-Suit] had 

either or both been reduced to practice or/and there was 

sufficient description of the patented method” by the critical date to allow for the implementation of the patent. 

J.A. 167.12 The District Court explained that the July 2003 

Valley LLC; Pacific Ethanol Stockton; Homeland Energy 

Solutions, LLC; Pacific Ethanol, Inc.; and David J. Vander 

Griend. 11 Notably, the August 2003 Email and the accompanying July 2003 Proposal were not produced during discovery in the infringement litigation before the District Court. 

J.A. 134.

12 The District Court initially determined that the onsale bar did not apply to the ’484 patent, J.A. 174, but later 

clarified its ruling, explaining that independent claim 30 of 

the ’484 patent was invalid under the on-sale bar because 

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Proposal contained the “major elements of a contract for 

the sale of a system that could perform the patented 

method . . . : [namely] all items necessary to recover oil 

and the price.” J.A. 167. The District Court stated that the 

“dealing between the parties” leading up to the July 2003 

Proposal evidences both parties’ understanding that it was 

an offer for sale. J.A. 168. The District Court relied upon 

the communications between VDT and Agri-Energy, as 

VDT had advised Agri-Energy about the system, how it 

would work, what it was comprised of, where it should be

placed, what it would accomplish, and the cost of operation. 

J.A. 168–69. The District Court concluded that, under the 

Uniform Commercial Code (“UCC”), the signed proposal 

would have constituted a commercial contract. J.A. 169. 

Further, the District Court explained that other evidence 

regarding VDT and Agri-Energy’s contact surrounding the 

July 2003 Proposal corroborated its conclusion. J.A. 169–

70 (referencing the creation of the Ethanol Oil Recovery 

System Diagram and Mr. Winsness’s announcement to 

shareholders that VDT had made an offer to sell and that 

the sale would lead to other sales). The District Court explained that a reasonable jury would not have concluded 

that the July 2003 Proposal was an offer to test its claimed 

invention as the Inventors knew the method could be successfully reduced to practice, J.A. 170–71 (listing evidence), 

and had been reduced to practice, J.A. 172 (citing Mr. Barlage’s two instances of practicing the method in 2003); see

J.A. 172–73 (referencing other communications between 

the Inventors, Agri-Energy, and others implicating a reduction to practice). Accordingly, the District Court invalidated all of the claims of the ’859, ’516, and ’517 patents, 

it required the same steps as the claims of the ’859, ’516, 

and ’517 patents that were also invalid, J.A. 234–35.

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20 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

and independent claim 30 of the ’484 patent pursuant to 

the on-sale bar.13 

Following its summary judgment determinations, the 

District Court held an inequitable conduct bench trial. 

13 In addition to the Patents-in-Suit, the District 

Court addressed the ’037 patent, which was not included in 

the subsequent inequitable conduct bench trial. J.A. 237–

38. The District Court determined that the ’037 patent was 

obvious over Prevost and the Patents-in-Suit. J.A. 215–16; 

see J.A. 214 (explaining that it was undisputed that the Patents-in-Suit served as prior art to the ’037 patent). Specifically, the District Court explained that Prevost and the 

Patents-in-Suit teach the oil recovery method for concentrated thin stillage, which is used with evaporators, as is 

disclosed by the ’037 patent. J.A. 215–16. Compare ’858 

patent col. 5 ll. 28–30, with ’037 patent col. 10 ll. 56–67. 

The District Court stated that a person having ordinary 

skill in the art (“PHOSITA”) would have been “familiar 

with the prior art ethanol plant processes,” like Prevost, 

that “includ[e] evaporation of thin stillage to reduce the 

moisture content before mixing it with wet distiller 

grains[.]” J.A. 215. The District Court explained that the 

Patents-in-Suit disclose dryer efficiencies that can be 

achieved from the removal of oil from syrup prior to any 

mixing with wet distiller grains. J.A. 215–16. Compare

’858 patent col. 4 ll. 54–56, col. 5 ll. 28–30, with ’037 patent 

col. 10 ll. 61–67. Because Prevost and the Patents-in-Suit 

disclose the drying of syrup after the oil extraction process 

but before it is added back to the dried distiller wet grains,

we conclude that the District Court properly determined 

that a PHOSITA would have been motivated to lower the 

moisture content of the syrup, as disclosed in the ’037 patent. See Regents of Univ. of Cal. v. Broad Inst., Inc., 903 

F.3d 1286, 1291 (Fed. Cir. 2018); see also 35 U.S.C. 

§ 103(a). 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 21

J.A. 237. Following the bench trial, in which the Inventors 

and attorneys from Cantor Colburn testified, the District 

Court concluded that additional evidence at trial supported 

the District Court’s previous determination that the Patents-in-Suit were ready for patenting when the Inventors 

provided the July 2003 Proposal to Agri-Energy. J.A. 294. 

The District Court concluded that CleanTech committed 

inequitable conduct through a “complete lack of regard for 

their duty to the [USPTO].” J.A. 261. Moreover, the District Court determined that “the [I]nventors made a mistake” by “offer[ing] their invention for sale to Agri-Energy” 

in “July/August 2003,” and “[l]ater, they took affirmative 

steps to hide that fact from their lawyers, then, later [from] 

the [US]PTO when they learned that it would prevent 

them from profiting from the [Patents-in-Suit].” J.A. 299. 

The District Court stated that the Inventors “purposefully 

withheld the information about their dealings with AgriEnergy[,]” J.A. 263, and that they “acted to deceive the 

[US]PTO about the facts of the discovery process of the invention[,]” J.A. 261. In discussing the Inventors’ “inten[t] 

to deceive the [US]PTO,” the District Court stated that the 

conclusion was evidenced by the fact that the Inventors “allowed [Mr.] Hagerty to file the feasibility testing letter during prosecution of the [’]858 patent, but [did] not tell the 

whole story about their 2003 successes and the [July 2003 

Proposal].” J.A. 292. Moreover, “[w]ith respect to the 

[’]516, the [’]517, and the [’]484 patents,” the District Court 

determined that “the [I]nventors allowed [Mr.] Hagerty to 

file a false affidavit notwithstanding their knowledge that 

[Mr.] Barlage had practiced the method in June 2003 and 

they had made an offer to sell the method to Agri-Energy 

in July or early August of 2003.” J.A. 292–93. 

Additionally, the District Court concluded that Cantor 

Colburn either “purpose[fully] eva[ded]” disclosing or failed 

to seek out relevant information and so participated in the 

inequitable conduct, J.A. 264, “cho[o]s[ing] advocacy over 

candor[,]” J.A. 308. The District Court explained that Mr. 

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22 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

Hagerty “never asked the [I]nventors key questions about 

their invention or the meaning of contemporaneous documents and, after the litigation started, [Mr. Hagerty] relied 

on the litigation team to do all the investigation.” J.A. 296. 

The District Court stated that Cantor Colburn’s focus on 

“pre-critical date documents” “was purposefully and, in 

[the District] Court’s view improperly narrow.” J.A. 300

(internal quotation marks omitted). The District Court 

also found that “[i]n the face of [Mr.] Cantrell’s poor health, 

[Mr.] Winsness’[s] and Cantor Colburn’s reliance on [Mr.] 

Cantrell’s recollection of the events surrounding the 

[July 2003 Proposal] . . . , as well as their lackluster investigation of events is solid evidence of purposeful behavior.” 

J.A. 307. The District Court determined that Cantor Colburn “ignored the red flags [waving] before them[,]” such 

as the fact that Mr. Winsness “threatened Agri-Energy 

with legal action if it did not corroborate his and 

[Mr.] Cantrell’s story[,]” which Cantor Colburn supported 

by sending Agri-Energy a “thinly-veiled threat[.]” J.A. 307, 

308.14 The District Court concluded that “[t]he only reasonable inference is that [Cantor Colburn] believed the 

[I]nventors had made an offer and, with the feasibility testing letter already before the [US]PTO in both 

14 At the bench trial, Mr. Hagerty testified that he 

had learned about the Inventors’ interactions with AgriEnergy around September 2008, including, significantly, 

the occurrence of the July 2003 testing. J.A. 263. When 

asked why he failed to provide the potential CleanTech investor with that information, Mr. Hagerty “seemed perplexed that [the] request should have covered the 2003 

testing because [Mr.] Hagerty had determined it was irrelevant to patentability.” J.A. 263. We conclude, as the District Court found, “[t]his conclusion is problematic in light 

of the fact that the written information [Mr.] Hagerty received from [Mr.] Winsness about the 2003 bench test 

stated that it worked[.]” J.A. 263. 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 23

prosecutions, . . . which implied a later reduction to practice date, they chose advocacy over candor.” J.A. 308. The 

District Court held the Patents-in-Suit unenforceable due 

to inequitable conduct. J.A. 313. 

DISCUSSION

I. Standard of Review and Legal Standard

“Inequitable conduct is an equitable issue committed to 

the discretion of the trial court and is, therefore, reviewed 

by this court under an abuse of discretion standard.” Energy Heating, LLC v. Heat On-The-Fly, LLC, 889 

F.3d 1291, 1299 (Fed. Cir. 2018) (citations omitted). We 

leave undisturbed the trial court’s inequitable conduct decision unless the appellant establishes “that the ruling is 

based upon clearly erroneous findings of fact or a misapplication or misinterpretation of applicable law or that the 

ruling evidences a clear error of judgment on the part of the 

[trial] court.” Kingsdown Med. Consultants, Ltd. v. Hollister Inc., 863 F.2d 867, 876 (Fed. Cir. 1988) (citation omitted) (en banc in relevant part).

To prevail on a claim of inequitable conduct in a patent 

case, the accused infringer must prove by clear and convincing evidence that the patentee: (1) “knew of the reference” or prior commercial sale; (2) “knew that it was 

material”; and (3) “made a deliberate decision to withhold 

it.” See Therasense, Inc. v. Becton, Dickinson & Co., 649 

F.3d 1276, 1290 (Fed. Cir. 2011) (en banc). “Proving that 

the [patentee] knew of a reference, should have known of 

its materiality, and decided not to submit it to the [US]PTO 

does not prove specific intent to deceive.” Id. Instead, “the 

specific intent to deceive must be the single most reasonable inference able to be drawn from the evidence.” Id. (internal quotation marks and citation omitted). 

The inequitable conduct claim here relates to whether 

the patentee failed to disclose information that would have 

implicated the on-sale bar under 35 U.S.C. § 102(b). A 

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patent is invalid under the on-sale bar if, before the critical 

date, the invention was: (1) the subject of a commercial 

sale or offer for sale; and (2) “ready for patenting.” Pfaff, 

525 U.S. at 67. First, whether the claimed invention was 

the subject of an offer for sale is an inquiry based on “contract law principles.” Linear Tech. Corp. v. Micrel, Inc., 275 

F.3d 1040, 1048 (Fed. Cir. 2001). “It also involves an assessment of whether the circumstances surrounding the 

transaction show that the transaction was not primarily for 

purposes of experimentation.” Allen Eng’g Corp. v. Bartell 

Indus., Inc., 299 F.3d 1336, 1352–53 (Fed. Cir. 2002). “A 

use may be experimental only if it is designed to (1) test 

claimed features of the invention or (2) . . . determine 

whether an invention will work for its intended purpose[.]” 

Clock Spring, L.P. v. Wrapmaster, Inc., 560 F.3d 1317, 1327 

(Fed. Cir. 2009) (involving a question of public use and not 

the on-sale bar but stating that “[t]hough a prior commercial sale and not a prior public use was at issue in Allen 

Engineering, the factors explicated are equally relevant to 

an analysis of experimental use”). To determine if a transaction was conducted primarily to experiment, a district 

court may look to the Allen factors to assess the transaction’s experimental nature. See Allen Eng’g, 299 F.3d 

at 1352–53. These factors include: “(1) the necessity for 

public testing, . . . (3) the nature of the invention,

[and] . . . (10) whether the invention reasonably requires 

evaluation under actual conditions of use[.]” Id. (citation 

omitted). If a prior commercial sale was primarily for purposes of experimentation, the sale will not serve as a bar. 

See Clock Spring, 560 F.3d at 1327. “In making this patentability determination, the [trial] court should apply the 

preponderance of the evidence standard[.]” Therasense, 

649 F.3d at 1291–92.

Second, “[a]n invention is ‘ready for patenting’ when 

prior to the critical date: (1) the invention is reduced to 

practice; or (2) the invention is depicted in drawings or described in writings of sufficient nature to enable a 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 25

[PHOSITA] to practice the invention.” Hamilton Beach 

Brands, Inc. v. Sunbeam Prods., 726 F.3d 1370, 1375 (Fed. 

Cir. 2013) (citation omitted) (emphases added). 

II. The District Court Did Not Abuse Its Discretion in Determining that the Patents-in-Suit Are Unenforceable 

Due to Inequitable Conduct15

After a bench trial, the District Court concluded that 

CleanTech and its attorneys at Cantor Colburn engaged in 

15 Despite CleanTech’s arguments to the contrary, see

Appellant’s Reply Br. 4, we will address the issue of inequitable conduct without first conducting a de novo review 

of the District Court’s summary judgment on-sale bar determination. A finding of a reference’s or prior sale’s materiality is required for an inequitable conduct 

determination, see Therasense, 649 F.3d at 1290, which is 

reviewed for abuse of discretion, see Energy Heating, 889 

F.3d at 1299. CleanTech contends that materiality may 

not be reviewed in the context of the inequitable conduct 

claim, as materiality was not properly raised before and 

addressed by the District Court during the inequitable conduct bench trial. Appellant’s Reply Br. 4–5. This argument 

is jejune. The District Court held an eight-day bench trial 

in which materiality was squarely before it. In addition to 

incorporating the evidence and findings of materiality that 

had been presented at the summary judgment stage, 

J.A. 237, the District Court admitted other relevant evidence during the trial, including documents relating to the 

June and July 2003 testing, J.A. 40144–45, 40153–54, and 

previously unheard testimony from the Inventors and attorneys with Cantor Colburn, J.A. 294, all relating to the 

materiality of the July 2003 Proposal. Moreover, following 

the bench trial, the District Court determined that “its conclusion [from the Summary Judgment Order] that [the 

July 2003 Proposal] evidence both elements of the on-sale 

bar” was “confirm[ed]” and, after incorporating “by 

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inequitable conduct in obtaining the Patents-in-Suit, rendering the patents unenforceable. J.A. 313. On appeal, 

CleanTech argues that the District Court made clearly erroneous findings of fact and misapplied the law with respect to its on-sale bar determination, as well as its 

conclusions regarding the parties’ knowledge of materiality 

and their intent to deceive. Appellant’s Br. 104, 109–10. 

We disagree with CleanTech. 

A. On-Sale Bar

The District Court “conclude[d] that the undisputed 

contemporaneous evidence supports only one conclusion, 

[that] the on-sale bar applies and invalidates the [Patentsin-Suit] because” the claimed invention was the subject of 

an offer for commercial sale and it was ready for patenting. 

J.A. 167. We address each determination in turn. 

1. The District Court Did Not Abuse Its Discretion in Determining the Claimed Invention Was the Subject of a 

Pre-Critical Date Offer for Sale

The District Court concluded that the July 2003 Proposal constituted a pre-critical-date offer for sale. J.A. 299. 

reference the findings of fact and conclusions of law in the 

Summary Judgment Order,” the District Court determined 

that “[f]urther evidence at trial only buttresse[d] the [District] Court’s earlier conclusion, particularly with respect 

to the ready for patenting element of the on-sale bar.” J.A. 

294. Additionally, despite CleanTech’s suggestions to the 

contrary, see Appellant’s Br. 105, inequitable conduct’s materiality requirement does not provide the patentee with 

the right to a jury and instead must be resolved by the trial 

court, see Am. Calcar, Inc. v. Am. Honda Motor Co., Inc., 

651 F.3d 1318, 1333 (Fed. Cir. 2011) (“Inequitable conduct 

is equitable in nature, with no right to a jury, and the trial 

court has the obligation to resolve the underlying facts of 

materiality and intent.”).

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CleanTech contends that it was not an offer as it “did not 

in fact perform the method for Agri-Energy, before the critical date, for a promise of future compensation.” Appellant’s Br. 37 (internal quotation marks and emphasis 

omitted) (citing Plumtree Software, Inc. v. Datamize, LLC, 

473 F.3d 1152, 1162–63 (Fed. Cir. 2006)). We disagree with 

CleanTech. 

The District Court did not abuse its discretion in determining that the claimed invention was the subject of an offer for sale in the summer of 2003. First, relying on the 

UCC, the District Court concluded that the July 2003 Proposal was a “sale on approval” that was made before the 

critical date. J.A. 169 (citing U.C.C. § 2-326); see U.C.C.

§ 2-326(1)(a) (“[I]f delivered goods may be returned by the 

buyer even though they conform to the contract, the transaction is . . . a ‘sale on approval’ if the goods are delivered 

primarily for use[.]”); see also Linear, 275 F.3d at 1052 (explaining “that the [UCC] should inform the [district court’s] 

analysis of the contractual issues[,]” such as the on-sale 

bar). The July 2003 Proposal provides an offer of “all items 

necessary to recover oil and the price,” J.A. 167, and the 

Inventors understood the offer to Agri-Energy was a “first 

sale” that would lead to additional sales, J.A. 170–72. Accordingly, the District Court properly concluded that the 

July 2003 Proposal was an “offer for sale.” Pfaff, 525 U.S. 

at 67. 

CleanTech’s primary counterargument is unavailing. 

CleanTech contends that the District Court misconstrued 

the law by failing to apply Plumtree’s requirement that the 

“challenger must prove that the patentee either: (i) ‘made 

a commercial offer to perform the patented method[]’[;] or 

(ii) ‘in fact performed the patented method for a promise of 

future compensation.’” Appellant’s Br. 36. CleanTech, 

however, did not make this argument before the District 

Court and cited to Plumtree only once in its summary judgment opposition and only for the proposition that the 

July 2003 Proposal was not invalidating because it “did not 

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28 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

unambiguously require use of [CleanTech’s] patented 

methods[.]” J.A. 26364 (citing Plumtree, 473 F.3d at 1163). 

Because we apply the law of the regional circuit as to procedural matters, see Info-Hold, Inc. v. Muzak LLC, 783 

F.3d 1365, 1371 (Fed. Cir. 2015), here the Seventh Circuit, 

we will not decide an issue for the first time on appeal, see 

Scheurer v. Fromm Family Foods LLC, 863 F.3d 748, 755 

(7th Cir. 2017) (“The well-established rule in th[e Seventh] 

Circuit is that a plaintiff waives the right to argue an issue 

on appeal if she fails to raise the issue before a lower court.” 

(internal quotation marks and citation omitted)). 

2. The District Court Did Not Abuse Its Discretion in Determining the Claimed Invention Was Ready for Patenting Before the Critical Date

The District Court determined that the claimed invention was ready for patenting prior to the critical date. 

J.A. 167. CleanTech contends that the District Court failed 

to find that the claimed invention was reduced to practice 

“on a claim-by-claim basis” for each of the Patents-in-Suit. 

Appellant’s Br. 46. We disagree with CleanTech. 

The District Court did not abuse its discretion in determining the claimed invention was ready for patenting in 

June or July 2003. First, with respect to the reduction to 

practice, the District Court relied upon the two tests conducted by Mr. Barlage in the summer of 2003 to support its 

determination. J.A. 126–27; see Hamilton Beach Brands, 

726 F.3d at 1375 (“An invention is ‘ready for patenting’ 

when prior to the critical date: . . . the invention is reduced 

to practice[.]” (emphasis added) (citation omitted)). The 

District Court explained that, in June 2003, Mr. Barlage 

tested an ethanol syrup with a pH, moisture content, and 

temperature within the claimed ranges recited in the Patents-in-Suit, compare J.A. 125–26 (describing Mr. Barlage’s testing, which heated thin stillage to a temperature 

of 176 oF, with a pH of “approximately 4, and moisture content between 70% and 80%”), with J.A. 920 (’516 patent)

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(Dependent Claim 6) (reciting “[a] method of recovering oil 

from thin stillage” with a temperature between 150 oF and 

212 oF, a pH between 3 and 6, and a moisture content of 

greater than 30% and less than 90% by weight), and separated oil from the syrup with a centrifuge, reporting that 

“the oil can be taken out easily,” J.A. 125–26, 171. Indeed,

the Inventors themselves made statements contemporaneous to the June and July 2003 testing that the claimed invention was reduced to practice. J.A. 127 (Mr. Cantrell 

stating to Agri-Energy following the July 2003 Test that 

“‘[t]he technology is available to remove the oil, and the 

quick payback from the new revenue stream, make this a 

very viable program’”), 111065 (Mr. Dorisio’s Draft Clearance Opinion to the Inventors) (“Past correspondence indicates your actual reduction to practice of the removing oil 

from syrup aspect of the proposed invention during experiments conducted in early to mid-June 2003.” (emphases 

added)). Moreover, immediately following the July 2003 

Test, Mr. Winsness then directed a VDT employee to prepare the Ethanol Oil Recovery System Diagram, J.A. 130–

32; see J.A. 110044 (Ethanol Oil Recovery System Diagram), which the employee understood “was intended to become a sales drawing[,]” J.A. 132 (internal quotation marks 

omitted); see J.A. 246 (the VDT employee “understood that 

the drawings would be used for sales purposes by [Mr.] 

Cantrell and [Mr.] Winsness”). The District Court, after 

reviewing the evidence, did not abuse its discretion in determining that “the method of the patented invention . . . had been performed” during June and July 2003. 

J.A. 171. 

CleanTech’s counterarguments are meritless and misleading. CleanTech disputes the District Court’s determination that the June and July 2003 testing was not 

experimental, arguing that there were “genuine factual 

disputes on [its] ‘commercial’ v[ersus] ‘experimental’” nature. Appellant’s Br. 39 (capitalization modified). Specifically, CleanTech argues that “nearly all” of the Allen

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30 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

factors support the experimental nature of the July 2003 

Proposal. Id. at 40. As an initial matter, CleanTech misrepresents the Allen factors and supports its arguments 

with testimony that was discredited by the District Court. 

Compare id. (“Allen factors [one] and [ten] ask whether the 

inventors ‘needed’ to experiment with the invention ‘under 

actual conditions of use.’” (internal brackets and emphasis 

omitted)), with Allen Eng’g, 299 F.3d at 1353 (explaining 

that factor one assesses whether there is “the necessity for 

public testing” and factor ten addresses “whether the invention reasonably requires evaluation under actual conditions of use”). CleanTech argues its testing was 

experimental because its claimed invention “clearly” 

“‘needed’ to experiment with the invention ‘under actual 

conditions of use.’” Appellant’s Br. 40 (quoting Allen Eng’g, 

299 F.3d at 1353) (internal brackets omitted). The District 

Court did not abuse its discretion in discounting this argument, as it explained that a “reduction to practice does not 

require a showing that the method would work acceptably 

in a plant environment, unless the claims require it, and

the claims here do not.” J.A. 172 (internal quotation marks 

and citation omitted); see In re Cygnus Telecomms. Tech., 

LLC, 536 F.3d 1343, 1355 (Fed. Cir. 2008) (explaining that 

a system that would not have worked on a “commercial 

scale[,]” but that “embodied the claims” of the “patents at 

issue[,]” satisfied the “‘ready for patenting’ prong” of the onsale bar). The District Court considered the Allen factors 

and concluded that the offer to Agri-Energy was an offer

for sale and not for purposes of experimentation. J.A. 167; 

see Allen Eng’g, 299 F.3d at 1352–53. For these reasons, 

we conclude that the District Court did not clearly err in 

its determination. 

Second, the District Court found the claimed invention 

was ready for patenting because it had been depicted and 

described in such a way that a PHOSITA would be able to 

practice it. J.A. 172–73; see Hamilton Beach Brands, 726 

F.3d at 1375 (“An invention is ‘ready for patenting’ when 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 31

prior to the critical date . . . the invention is depicted in 

drawings or described in writings of sufficient nature to enable a [PHOSITA] to practice the invention.” (emphasis 

added) (citation omitted)). Despite CleanTech’s argument 

that its expert opined the Inventors had not prepared 

drawings or other descriptions of the invention that were 

sufficiently specific to enable a PHOSITA to practice it, see

Appellant’s Reply Br. 18 (emphasis omitted), Appellant’s 

Br. 47, the District Court determined that, while there was 

no “single reference that specifically delineate[d]” the 

method “disclosed by the [Patents-in-Suit], the Ethanol 

[Oil Recovery] System Diagram” in combination “with 

[Mr.] Barlage’s lab tests and results” and “communications 

from [Mr.] Cantrell to Agri-Energy . . . would allow a 

[PHOSITA] to practice the invention of the [Patents-inSuit,]” J.A. 173. The District Court explained that “[t]here 

is no mystery or dispute that the pH, moisture content[,]

and temperature ranges in the claims of the [Patents-inSuit] are those that occur at the standard operating conditions of a dry mill ethanol plant.” J.A. 173. CleanTech has 

not shown clear error in these factual findings and we reject the invitation to reweigh the evidence. Accordingly, 

the District Court did not abuse its discretion in its on-sale 

bar determination. 

B. The District Court Did Not Abuse Its Discretion in 

Concluding that CleanTech and Its Lawyers Made a Deliberate Decision to Withhold Material Information with 

the Specific Intent to Deceive the USPTO

The District Court concluded that CleanTech knew of 

the claimed invention’s offer for sale and reduction to practice in the summer of 2003, as well as that information’s 

materiality. J.A. 303, 308. The District Court “conclude[d] 

that the [I]nventors and the[ir] attorneys intentionally 

withheld material information from the [US]PTO during 

prosecution” of the Patents-in-Suit, thereby rendering the 

Patents-in-Suit unenforceable due to inequitable conduct. 

J.A. 312; see Therasense, 649 F.3d at 1290 (explaining that 

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32 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

inequitable conduct requires a showing of clear and convincing evidence that the patentee “knew of the reference, 

knew that it was material, and made a deliberate decision 

to withhold it”). CleanTech contends that that District 

Court erred in its materiality and intent to deceive findings. Appellant’s Br. 104–05. We disagree with CleanTech. 

The District Court did not abuse its discretion in rendering unenforceable the Patents-in-Suit for inequitable 

conduct. For the reasons discussed above, see supra Section II.A, we conclude that the District Court did not abuse 

its discretion in concluding that CleanTech and its attorneys were aware that the claimed invention was ready for 

patenting, as evidenced by documents belatedly or not 

turned over to the USPTO, and that they knew of those 

documents’ materiality. In addition to knowledge and materiality, inequitable conduct requires a clear and convincing showing that CleanTech “made a deliberate decision to 

withhold” the material information. See Therasense, 649 

F.3d at 1290. Moreover, “the specific intent to deceive must 

be ‘the single most reasonable inference drawn from the evidence.’” Id. Here, the District Court did not abuse its discretion in determining for numerous reasons that 

CleanTech deliberately withheld material information. 

First, the District Court concluded that CleanTech 

knew the July 2003 Proposal to Agri-Energy threatened its 

chances of patenting its ethanol oil recovery method. 

J.A. 299 (explaining “that the [I]nventors made a mistake 

in July/August 2003 and offered their invention for sale to 

Agri-Energy” and “[l]ater . . . took affirmative steps to hide 

that fact from their lawyers, then, later the [US]PTO when 

they learned that it would prevent them from profiting 

from the patents”). This determination is supported by the 

record. In February 2004, the Inventors sought information from the USPTO website about provisional patent 

applications and the on-sale bar. J.A. 252. Days later, Mr.

Dorisio informed the Inventors about the on-sale bar. 

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J.A. 252. The District Court did not clearly err in finding 

that CleanTech was aware of the on-sale bar and its requirements. See Energy Heating, 889 F.3d at 1302–03 

(concluding that the district court did not abuse its discretion in finding an inventor’s knowledge that sales of the 

claimed invention prior to the critical date were material, 

and the inventor’s failure to disclose the sales was intended 

to deceive the USPTO). 

Second, the District Court found that the Inventors and

the attorneys at Cantor Colburn withheld evidence of successful testing in 2003 and made false representations by

implying that the invention was not reduced to practice until 2004. J.A. 302 (“[N]ot providing information regarding 

the [I]nventors’ dealings with Agri-Energy or [Mr.] Barlage[’s] bench-top test raises an inference that the patentees intended to deceive the [US]PTO—it was pre-critical 

date information that had a direct bearing on the ability of 

the [I]nventors to prove that their claims were patentable.”). This finding is supported by the record. Cantor Colburn began representing CleanTech in March 2008 and, by 

at least September 2008, were aware of Mr. Barlage’s testing in June and July 2003. J.A. 111075. Mr. Winsness informed Cantor Colburn that the “testing we did in 

June 2003” showed that “a sequence of evaporation followed by centrifugation allows for oil recovery[.]” 

J.A. 111075. Moreover, the Inventors informed Cantor 

Colburn that, based on the summer 2003 testing, the Inventors “believe[d] [that] the process would work on a commercial scale.” J.A. 263 (internal quotation marks 

omitted). Cantor Colburn was also in possession of the 

Ethanol Oil Recovery System Diagram and the test reports 

themselves. J.A. 301. Despite possessing this information, 

Cantor Colburn did not provide it to the USPTO during the 

prosecution of the Patents-in-Suit and referenced it only to 

assert that the claimed invention predated Prevost. 

J.A. 301–02, 304–06, 309. Moreover, in June 2009, Cantor 

Colburn filed a letter with the USPTO stating that 

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feasibility testing occurred in May 2004, with no mention 

of the documents dated a year earlier. J.A. 303. This letter 

was filed in the prosecutions of each of the Patents-in-Suit. 

J.A. 304–05. The District Court did not clearly err in its 

finding that CleanTech and Cantor Colburn withheld material evidence from the USPTO. See Molins PLC v. Textron, Inc., 48 F.3d 1172, 1178 (Fed. Cir. 1995) (“[Patentees] 

who are not ‘up front’ with the [US]PTO run the risk that, 

years later, a fact-finder might conclude they intended to 

deceive. This is what appears to have happened here and 

we must affirm the trial court.”); see also id. (“Applicants 

for patents are required to prosecute patent applications in 

the [US]PTO with candor, good faith, and honesty. . . . This 

duty extends also to the applicant’s representatives.” (internal footnote and citations omitted)). 

Third, the District Court determined that CleanTech

and Cantor Colburn “threatened” Agri-Energy to coerce its 

support regarding the critical date for the Patents-in-Suit, 

after the July 2003 Proposal surfaced and during the pendency of the ’516 and ’517 patents. J.A. 308. Specifically, 

in June 2009, Mr. Winsness traveled to Agri-Energy and 

“offered Agri-Energy a royalty-free license in exchange for 

Agri-Energy’s willingness to admit that the pending patents were valid.” J.A. 269. In July 2009, Cantor Colburn 

sent Agri-Energy an email offering “a release of liability for 

any prior use of an extraction system” and indemnification 

“against any liability” in return “for cooperating with 

[CleanTech] and for clarifying the use of the corn oil system 

in 2004.” J.A. 110322. Moreover, Cantor Colburn requested a statement “confirming and clarifying” certain 

facts relating to the offer. J.A. 110322–23. Agri-Energy’s 

manager testified that he “did not accept the offer from 

[Cantor Colburn and CleanTech] because the statements 

were not true.” J.A. 271. Notably, Cantor Colburn “failed 

to request that Agri-Energy provide any documents” regarding its interactions with the Inventors. J.A. 271. The 

District Court did not abuse its discretion in concluding 

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that these attempts to threaten Agri-Energy spoke to 

CleanTech’s and Cantor Colburn’s intent to deceive the 

USPTO. 

Fourth, the District Court concluded that the Inventors

and Cantor Colburn made a “patently false” statement in 

the First Cantrell Declaration, by claiming the July 2003 

Proposal was delivered to Agri-Energy after the critical 

date. J.A. 276; see J.A. 307 (“[T]he [I]nventors and attorneys misrepresented to the [US]PTO that the [July 2003 

Proposal] was immaterial by filing the false [First] 

Cantrell . . . Declaration[.]”). The District Court’s determination that the declaration was false is supported by the 

evidence. Specifically, it was not until August 2010 that 

Mr. Cantrell told Cantor Colburn that he recalled he had 

personally delivered the July 2003 Proposal to Agri-Energy 

on August 18, 2003. J.A. 272. The attorneys at Cantor 

Colburn testified that they themselves were skeptical of 

the veracity of the claim, as the date specified by Mr. 

Cantrell would alleviate all concerns about the on-sale bar. 

J.A. 272–73. Nonetheless, Cantor Colburn filed the First 

Cantrell Declaration in November 2010 for the ’516 and 

’517 patent prosecutions, J.A. 276–77, and in the ’484 patent prosecution in July 2011, J.A. 277. This was done notwithstanding the Inventors’ knowledge that Mr. Barlage 

had practiced the claimed method in June 2003 and they 

had offered to sell the claimed invention to Agri-Energy in 

July or early August of 2003. J.A. 292–93; see Rohm & 

Haas Co. v. Crystal Chem. Co., 722 F.2d 1556, 1571 (Fed. 

Cir. 1983) (“[T]here is no room to argue that submission of 

false affidavits is not material.”). Moreover, prior to Mr. 

Cantrell’s August 2010 statement, Cantor Colburn had 

prepared a detailed disclosure that included information 

about the June and July 2003 Tests and Report and the 

Ethanol Oil Recovery System Diagram, which the law firm 

had possessed since September 2008. J.A. 308; see

J.A. 111075–104 (Email from Mr. Winsness to Mr. Hagerty 

Dated September 2008) (providing “some history of testing 

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we did in June 2003 to discover that a sequence of evaporation followed by centrifugation allows for oil recovery[,]” 

including the June 2003 Report). Following Mr. Cantrell’s 

statements, the disclosure was discarded and never filed in 

any patent prosecution. J.A. 308. Based on this, the District Court concluded that “[t]he only reasonable inference

is that [Cantor Colburn] believed the [I]nventors had made 

an offer and, with the feasibility testing letter already before the [US]PTO in both prosecutions, . . . which implied a 

later reduction to practice date, they chose advocacy over 

candor.” J.A. 308 (emphases added). The District Court 

did not abuse its discretion in concluding that the “patently 

false” statement in the First Cantrell Declaration was material and supported its intent to deceive determination. 

Fifth, the District Court explained that the Inventors’

and Cantor Colburn’s failure to correct the false declaration in the ’484 patent prosecution was “strong evidence of 

intentional deceit[.]” J.A. 309. Specifically, at Mr. 

Cantrell’s September 2011 deposition, where Mr. Cantrell 

and Cantor Colburn “kn[e]w for certain that [Mr.] 

Cantrell’s First Declaration [was] false,” no correction was 

made then or during the following eight months. J.A. 309 

(emphasis added); see J.A 280 (“Most disturbing is that, 

during this period, neither litigation counsel nor [Mr.] 

Hagerty did anything to alert the [US]PTO that [Mr.] 

Cantrell’s First Declaration was false[.]”). In July 2012, 

the Second Cantrell Declaration was filed with the USPTO, 

in which Mr. Cantrell attested that “[a]ttached is an e-mail 

sent from my e-mail account on August 1, 2003” and that 

“[t]he [July 2003 Proposal] attached to the August 1 email 

was unsigned.” J.A. 110274. As the District Court explained, the Second Cantrell Declaration provided “the 

false impressions that [Mr.] Cantrell may not have sent the 

[August 2003 Email] and that the unsigned letter had less 

significance than the ‘signed’ one he allegedly hand delivered later the same month,” it “repeats false information,” 

and “fails to distinctly point out and/or explain the false 

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information previously provided to the examiner[.]” 

J.A. 283. Based on this evidence, we conclude that the District Court did not abuse its discretion in concluding that, 

by clear and convincing evidence, the single most reasonable inference to be drawn from the record was that the Inventors and Cantor Colburn intended to deceive the 

USPTO. See Energy Heating, 889 F.3d at 1302–03. 

CleanTech raises numerous counterarguments, all of 

which are unavailing. First, CleanTech argues that the 

District Court’s review of materiality “exceeded the scope 

of the bench trial, which was only on ‘inequitable conduct.’” 

Appellant’s Br. 105. Materiality is, however, an element of 

the inequitable conduct claim and was squarely before the 

District Court. See Therasense, 649 F.3d at 1290 (“In a case 

involving nondisclosure of information, clear and convincing evidence must show that the applicant made a deliberate decision to withhold a known material reference.” 

(internal quotation marks and citation omitted) (emphasis 

altered)). In fact, CleanTech itself raised materiality in 

pre-trial briefing, contending that the Appellants “will also 

not be able to establish that any of the alleged errors and 

omissions, aside from the misstatements found in [Mr.]

Cantrell’s first declaration, would have been ‘but-for’ material.” J.A. 63467. Accordingly, the District Court did not 

err in making a materiality determination.

Second, CleanTech avers that the District Court’s materiality finding violated its right to a jury trial. Appellant’s Br. 105. Given that inequitable conduct is based in 

equity, there is no right to a jury trial. See Am. Calcar, 651 

F.3d at 1333 (“Inequitable conduct is equitable in nature, 

with no right to a jury, and the trial court has the obligation to resolve the underlying facts of materiality and intent.”).

Third, CleanTech contends that the District Court 

“barred CleanTech from re-litigating materiality” by excluding some evidence involving the USPTO’s actions 

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38 GS CLEANTECH CORP. v. ADKINS ENERGY LLC

permitting “a continuation in the [Patents-in-Suit]” even 

after the USPTO was provided with evidence of the July 

2003 Proposal and related materials. Appellant’s Br. 105–

06. The evidence was excluded under Federal Rule of Evidence 403, because the District Court determined that its 

probative value was outweighed by the likelihood that it 

would confuse and prolong the trial. J.A. 71952–53; see

Fed. R. Evid. 403 (“The court may exclude relevant evidence if its probative value is substantially outweighed by 

a danger of one or more of the following: unfair prejudice, 

confusing the issues, . . . undue delay, [or] wasting 

time[.]”). To the extent that CleanTech is contesting the 

Rule 403 determination, it did not do so before the District 

Court and so waives the issue here. See Scheurer, 863 F.3d 

at 755. Accordingly, the District Court did not abuse its 

discretion in reaching its inequitable conduct determination.16

CONCLUSION

We have considered the parties’ other arguments and

each of the remaining issues raised on appeal and crossappeal and find them to be without merit. Accordingly, the 

judgments below are

AFFIRMED

16 As we affirm the District Court’s determination 

that the Patents-in-Suit are unenforceable due to the inequitable conduct, we need not address CleanTech’s additional arguments regarding the other grounds upon which 

the District Court ruled the Patents-in-Suit invalid. See

Energy Heating, 889 F.3d at 1308 (concluding that, where 

a trial court’s judgment that a “patent is unenforceable for 

inequitable conduct” is affirmed, this court need “not reach 

the [trial] court’s summary judgment of obviousness, claim 

construction order, or summary judgment of no direct infringement”). 

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GS CLEANTECH CORP. v. ADKINS ENERGY LLC 39

COSTS

Costs to the Appellees and Cross-Appellant.

Case: 16-2231 Document: 164 Page: 39 Filed: 03/02/2020