United Therapeutics Corporation v. Liquidia Technologies, Inc.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
UNITED THERAPEUTICS CORPORATION,
Appellant
v.
LIQUIDIA TECHNOLOGIES, INC.,
Appellee
KATHERINE K. VIDAL, UNDER SECRETARY OF
COMMERCE FOR INTELLECTUAL PROPERTY
AND DIRECTOR OF THE UNITED STATES
PATENT AND TRADEMARK OFFICE,
Intervenor
______________________
2022-2133
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2020-
00770.
______________________
Decided: June 27, 2024
______________________
WILLIAM M. J AY , Goodwin Procter LLP, Washington,
DC, argued for appellant. Also represented by WILLIAM
COVINGTON J ACKSON, J AIME SANTOS , ROHINIYURIE
T ASHIMA, J ENNY J. ZHANG; A DAM WILLIAM B URROWBRIDGE ,
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McDermott Will & Emery, LLP, Washington, DC; D OUGLAS
H. CARSTEN, ARTHUR P AUL D YKHUIS , Irvine, CA; SHAUN R.
SNADER, United Therapeutics Corporation, Washington,
DC.
SANYA SUKDUANG , Cooley LLP, Washington, DC, ar-
gued for appellee. Also represented by J ONATHAN D AVIES .
MAUREEN D ONOVAN Q UELER , Office of the Solicitor,
United States Patent and Trademark Office, Alexandria,
VA, argued for intervenor. Also represented by MARY L.
K ELLY , F ARHEENA YASMEEN RASHEED.
______________________
Before H UGHES , STOLL , and CUNNINGHAM , Circuit Judges.
STOLL , Circuit Judge.
This is the case of a missing oath and purportedly miss-
ing claim limitation. United Therapeutics Corporation
(UTC) appeals the Patent Trial and Appeal Board’s final
written decision denying UTC’s motion to exclude the dec-
laration of Dr. Jeffrey D. Winkler for failure to include an
oath. UTC also appeals the Board’s final written decision
holding certain claims of U.S. Patent No. 9,604,901 un-
patentable as obvious. We affirm the Board’s denial of
UTC’s motion to exclude and its obviousness determina-
tion.
BACKGROUND
The ’901 patent includes “an improved process to con-
vert benzindene triol to treprostinil via salts of treprostinil
and to purify treprostinil.” ’901 patent, Abstract. Trepros-
tinil is the active ingredient in UTC’s drug Remodulin®, id.
at col. 1 ll. 27–32, which is used to treat pulmonary arterial
hypertension, i.e., high blood pressure in the arteries that
go from the heart to the lungs. According to the ’901 pa-
tent, because treprostinil is “of great importance from a
medicinal point of view, a need exists for an efficient
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process to synthesize th[is] compound[] on a large scale
suitable for commercial production.” Id. at col. 1 l. 66–
col. 2 l. 3. The ’901 patent discloses “a process for the prep-
aration of [treprostinil], or a hydrate, solvate, or pharma-
ceutically acceptable salt thereof.” Id. at col. 8 ll. 44–46.
Claim 1 is the only independent claim and is reproduced
below:
1. A pharmaceutical batch consisting of treprosti-
nil or a salt thereof and impurities resulting from
(a) alkylating a benzindene triol, (b) hydrolyzing
the product of step (a) to form a solution comprising
treprostinil, (c) contacting the solution comprising
treprostinil from step (b) with a base to form a salt
of treprostinil, (d) isolating the salt of treprostinil,
and (e) optionally reacting the salt of treprostinil
with an acid to form treprostinil, and wherein the
pharmaceutical batch contains at least 2.9 g of
treprostinil or its salt.
’901 patent, col. 17 l. 24–col. 18 l. 2.
Liquidia’s petition for inter partes review (IPR) asserts
that the ’901 patent is rendered obvious by Moriarty1 in
view of Phares2. Prior art references Moriarty and Phares
describe preparation methods of treprostinil. As relevant
to this appeal, Moriarty discloses synthesizing treprostinil
“via the stereoselective intramolecular Pauson-Khand cy-
clization,” which is a known way of producing treprostinil.
J.A. 1471–78. And Phares teaches various compounds, in-
cluding treprostinil and its derivatives. Phares states that
1 Moriarty et al., The Intramolecular Asymmetric
Pauson-Khand Cyclization as a Novel and General Stere-
oselective Route to Benzindene Prostacyclins: Synthesis of
UT-15 (Treprostinil), 69 J. Organic Chemistry 1890, 1890–
902 (2004).
2 PCT Application No. WO 2005/007081 A9.
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“[a] preferred embodiment of the present invention is the
diethanolamine salt of treprostinil.” J.A. 1359. Phares fur-
ther teaches that “the enantiomer of the commercial drug
(+)-Treprostinil was synthesized using the stereoselective
intramolecular Pauson Khand reaction as a key step and
Mitsunobu inversion of the side-chain hydroxyl group.”
J.A. 1390.
Liquidia’s IPR petition also included the declaration of
Dr. Jeffrey D. Winkler. J.A. 91; J.A. 94; J.A. 877. The
Winkler Declaration contained a signature but lacked any
affirmations of truthfulness or any acknowledgement of
the punishment for false statements. Following institu-
tion, UTC timely served objections to the Winkler Declara-
tion. UTC objected to the Winkler declaration as, among
other things, “lacking authentication and not self-authen-
ticating because it lacks sufficient indicia that the exhibit
is what it purports to be.” J.A. 331. While Liquidia later
filed a corrected Winkler declaration with an oath, the fil-
ing was late and Liquidia did not serve any timely supple-
mental evidence in response to UTC’s objection to the
Winkler declaration. See J.A. 54–57; J.A. 589; 37 C.F.R.
§ 42.64(b)(2).
Prior to filing its Patent Owner response, UTC deposed
Dr. Winkler about his declaration. During the deposition,
Dr. Winkler confirmed that he would provide truthful and
accurate testimony, he had written the declaration, and
that the declaration contained his signature.
Prior to the oral argument, UTC timely filed a motion
to exclude the Winkler Declaration because it “purports to
be a declaration, but without authentication because it
lacks the statutorily-required oath or caveat for a declara-
tion.” J.A. 590 (citing 35 U.S.C. § 25 and 37 C.F.R. § 42.2).
UTC asserted that statements lacking the required certifi-
cations “forgo the guarantee of truthfulness imparted by a
declarant’s acknowledgment of the possible
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consequences—fine, imprisonment, or penalty of perjury.”
J.A. 590 (internal quotation marks and citation omitted).
Liquidia opposed the motion to exclude and asserted
that the deposition and refiled declaration rendered the
“inadvertently omitted” affirmations of truthfulness harm-
less and otherwise cured. J.A. 602–03. UTC replied that
Liquidia had never received Board authorization to file be-
lated supplemental evidence.
At oral argument, Liquidia explained that the missing
language in the Winkler Declaration was the result of a
paragraph being accidentally deleted during drafting and
not an intentional omission. Liquidia also emphasized the
lack of prejudice to UTC, given that UTC had conducted a
several-hour deposition of Dr. Winkler, and Liquidia had
filed a corrected declaration with an oath. The Board ex-
plained, however, that Liquidia did not follow Board rules
requiring parties to seek leave prior to submitting supple-
mental evidence and thus the corrected declaration would
be omitted. When questioned as to whether the ability to
depose Dr. Winkler resolved the issue of the missing oath,
UTC’s counsel reasonably conceded that he would be “hard
pressed to sit here and say, you know, that we suffered a
specific cognizable prejudice.” J.A. 759 at 64:05–06.
After the hearing, the Board issued a final written de-
cision finding that Liquidia had established by a prepon-
derance of evidence that claims 1–5, 8, and 9 were
unpatentable but had not demonstrated the unpatentabil-
ity of claims 6 and 7. The Board’s unpatentability decision
relied, at least in part, on the Winkler Declaration. The
Board also denied UTC’s motion to exclude the Winkler
declaration in its final written decision. J.A. 53–58. The
Board rejected Liquidia’s arguments of curing via the mod-
ified Winkler Declaration but agreed with Liquidia that be-
cause UTC deposed Dr. Winkler, UTC suffered no undue
prejudice.
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UTC timely appealed the Board’s decision. We have
jurisdiction under 28 U.S.C. § 1295(a)(4)(A).
D ISCUSSION
UTC raises two issues on appeal. First, UTC argues
that the Board erred in denying UTC’s motion to exclude
the Winkler Declaration. Second, UTC argues that the
Board erred in determining that the challenged claims are
unpatentable. We address each issue in turn.
I
Starting with the Board’s denial of UTC’s motion to ex-
clude the Winkler Declaration, we hold the Board complied
with the Administrative Procedure Act.
We review Board decisions for compliance with the Ad-
ministrative Procedure Act (APA) and set aside “actions of
the Board that are arbitrary, capricious, an abuse of dis-
cretion, or otherwise not in accordance with law.” In re
Sullivan, 362 F.3d 1324, 1326 (Fed. Cir. 2004); 5 U.S.C.
§ 706. More specifically, we review the Board’s procedural
or administrative decisions for an abuse of discretion. Net-
flix, Inc. v. DivX, LLC, 80 F.4th 1352, 1358 (Fed. Cir.
2023); see 5 U.S.C. § 706(2). An abuse of discretion occurs
when a decision “(1) is clearly unreasonable, arbitrary, or
fanciful; (2) is based on an erroneous conclusion of law;
(3) rests on [a] clearly erroneous fact finding; or (4) involves
a record that contains no evidence on which the Board
could rationally base its decision.” Intelligent Bio-Sys., Inc.
v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367 (Fed. Cir.
2016) (quoting Bilstad v. Wakalopulos, 386 F.3d 1116,
1121 (Fed. Cir. 2004)). And of course, when reviewing
agency action, we must take account of the rule of harmless
error. 5 U.S.C. § 706; Shinseki v. Sanders, 556 U.S. 396,
406 (2009) (holding that § 706 requires application of “the
same kind of ‘harmless-error’ rule that courts ordinarily
apply in civil cases”).
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UTC argues that “[b]y both statute and regulation, dec-
larations or affidavits must be sworn or contain indicia of
trustworthiness in order to be admissible.” Appellant’s
Br. 14, 19–20. Declarations or affidavits, in UTC’s view,
“must be accompanied by a warning that false statements
are punishable by fine or imprisonment, or include a certi-
fication that the statements made therein are true and are
offered under penalty of perjury.” Id. at 14 (citing
35 U.S.C. §§ 23, 25; 28 U.S.C. § 1746; 37 C.F.R. §§ 42.53(a),
42.2, 1.68). UTC concludes that declarations or affidavits
lacking such are “not admissible.” Id. (quoting 37 C.F.R.
§ 42.61(a)).
In response, the PTO and Liquidia both agree that an
oath or declaration is required by regulation but not by
statute. See Appellee’s Br. 22–23; Intervenor’s Br. 12–14.
Both the PTO and Liquidia also contend that consistent
with “its rule-making authority, the PTO maintain[s] the
discretion to ‘waive or suspend a [regulatory] requirement
of parts 1, 41, and 42,’” Appellee’s Br. 23 (quoting 37 C.F.R.
§ 42.5(b)), and here the Board exercised that discretion to
waive the attestation requirement under 37 C.F.R. §§ 1.68,
42. See Appellee’s Br. 22–24; Intervenor’s Br. 12–14.
Whether required by statute or regulation, it is clear
any declaration or affidavit submitted in IPR proceedings
must contain an oath or declaration. The purpose of the
oath or declaration is to provide a guarantee of truthful-
ness where, as here, the testimonial evidence is in paper
form. See Former Emps. of Barry Callebaut v. Chao,
357 F.3d 1377, 1383 (Fed. Cir. 2004). Moreover, this guar-
antee of truthfulness—a single line of language—is easy to
satisfy.
Here, Liquidia failed to include such an oath or decla-
ration in the Winkler Declaration. Yet, UTC made the
strategic decision to “rigorously” depose Dr. Winkler.
J.A. 758 at 63:12–15. UTC questioned Dr. Winkler about
his declaration under oath, see J.A. 12001, and confirmed
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there were no issues concerning the truthfulness of the
opinions in the Winkler Declaration. At the beginning of
the deposition, Dr. Winkler confirmed that he would “pro-
vide truthful, accurate testimony.” J.A. 12004 at 9:06–08.
Dr. Winkler confirmed that he wrote the Winkler Declara-
tion. J.A. 12013 at 18:11–13. Dr. Winkler even confirmed
his signature on the Winkler Declaration. J.A. 12014
at 19:08–21 (testifying as to his signature on the declara-
tion). These are the hallmark guarantees of truthfulness
that supplant the missing oath or declaration. Moreover,
it is clear that Dr. Winkler provided sworn testimony about
the Winkler Declaration that the Board could rely on. On
this record, we see no room to fault the Board’s decision to
rely on the Winkler Declaration.
For purposes of this opinion, we assume a statutory re-
quirement of an oath or declaration.3 Even with this as-
sumption, however, we find no harmful error in the Board’s
decision to rely on the Winkler Declaration. Under the
APA, we will not overturn an agency’s decision unless it
produced an error that was genuinely harmful or prejudi-
cial. See Swagway, LLC v. Int’l Trade Comm’n, 934 F.3d
1332, 1343 (Fed. Cir. 2019) (“The APA specifies that we
must take account of the rule of harmless error.”). UTC
fails to demonstrate such prejudice here. Critically, the
Board concluded that UTC had suffered no prejudice be-
cause UTC was able to rigorously depose Dr. Winkler on
his opinions, Dr. Winkler confirmed the truthfulness of his
declaration during the deposition, and UTC conceded that
it suffered no “specific cognizable prejudice.” J.A. 759
at 64:05–06. We see no error in the Board’s finding of no
prejudice under these circumstances.
At argument before this court, UTC stressed that the
Board focused on counsel’s statement out of context. See
3 Such statutory requirement cannot be waived by
the Board under 37 C.F.R. § 42.5.
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Oral Arg. at 3:28–5:00, https://oralargu-
ments.cafc.uscourts.gov/default.aspx?fl=22-2133_0206202
4.mp3. Read in context, it is UTC’s view that its counsel
identified two sources of prejudice to UTC. First, UTC ar-
gues it was deprived of the opportunity to oppose a Liquidia
motion to supplement the record with a corrected version
of the Winkler Declaration because Liquidia failed to follow
procedure and supplemented the record on its own. Sec-
ond, UTC argues that the fact that the Board relied on the
unsworn testimony of the Winkler Declaration is itself a
source of prejudice. Again, we see no harm.
While UTC did not get the opportunity to oppose a mo-
tion to supplement a defective declaration, UTC did file a
motion to exclude the defective Winkler Declaration. The
Board considered UTC’s motion, acknowledged Liquidia’s
improper efforts to supplement the record, and correctly
noted that “[UTC] deposed Dr. Winkler on his opinions” in
the Winkler Declaration. J.A. 58. As noted above,
Dr. Winkler testified under oath. Thus, contrary to UTC’s
assertion, the Board did rely on the sworn testimony of
Dr. Winkler in reaching its decision. Moreover, when
pressed, UTC could not adequately explain how it would
have changed its tactics, arguments, or deposition strategy.
Oral Arg. at 8:54–9:15, 11:23–13:35, https://oralargu-
ments.cafc.uscourts.gov/default.aspx?fl=22-2133_0206202
4.mp3. Further, as Liquidia and the PTO note, UTC re-
sponded to Dr. Winkler’s opinions in its Preliminary Re-
sponse, Patent Owner Response, Sur-Reply, and its own
expert’s declaration. Appellee’s Br. 25; Intervenor Br. 17–
18; see, e.g., J.A. 235, J.A. 368–69, J.A. 393, J.A. 528–29;
J.A. 3514–15. Therefore, we conclude that the Board did
not abuse its discretion in relying on the Winkler Declara-
tion because UTC had a full and fair opportunity to litigate
Dr. Winkler’s sworn opinions and suffered no prejudice.
At bottom, under the facts here, substance beats form.
We recognize Liquidia should have included an oath or dec-
laration in the Winkler Declaration or sought leave from
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the Board to supplement the Winkler Declaration in a
timely manner. Because UTC extensively deposed
Dr. Winkler, who confirmed the truthfulness of his testi-
mony, however, there is no prejudice here. Although this
might create a perverse incentive for a party to not depose
a declarant who failed to include an oath or declaration
with her affidavit, we are confident the parties will con-
tinue to police one another and exercise caution in prepar-
ing declarations in support of IPR petitions. Litigation is a
risky business, and careful inclusion of an oath or affidavit
can eliminate the risk that both UTC and Liquidia bore
here.
II
Now, we address obviousness. “We review the Board’s
legal conclusions de novo and its factual findings for sub-
stantial evidence.” Univ. of Strathclyde v. Clear-Vu Light-
ing LLC, 17 F.4th 155, 160 (Fed. Cir. 2021). “The
substantial evidence standard asks ‘whether a reasonable
fact finder could have arrived at the agency’s decision,’ and
‘involves examination of the record as a whole, taking into
account evidence that both justifies and detracts from an
agency’s decision.’” OSI Pharms., LLC v. Apotex, Inc.,
939 F.3d 1375, 1381–82 (Fed. Cir. 2019) (quoting In re
Gartside, 203 F.3d 1305, 1312 (Fed. Cir. 2000)). UTC ar-
gues the Board’s underlying fact findings on scope and con-
tent of the prior art and motivation to combine are not
supported by substantial evidence because the Board relied
on Dr. Winkler’s opinions, which, according to UTC, “cited
to no actual evidence of the asserted motivation in the prior
art” and instead relied on “common sense” to “take the
place of actual evidence showing that a [person of ordinary
skill] would have viewed omitting [the] isolation steps as
both feasible and cost saving.” Appellant’s Br. 35–36. We
disagree with both assertions.
First, the Board’s determination that a person of ordi-
nary skill would have been motivated to combine prior art
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references Moriarty and Phares, without an isolation step,
is supported by substantial evidence. In reaching its deter-
mination, the Board relied on the prior art references Mo-
riarty and Phares, the Winkler Declaration, the Winkler
Reply Declaration, and the testimony of Dr. Pinal. See
J.A. 35–40.
Starting with the prior art references, the Board rea-
sonably found “that an ordinarily skilled artisan would
have had a reason to start with the treprostinil free acid of
Moriarty and convert it into the diethanolamine salt,”
J.A. 36, because Moriarty and Phares were directed to re-
lated problems and both experts recognized that Moriarty
teaches “a well-known way to make treprostinil,” J.A. 932,
and that “Phares teaches how to take that treprostinil and
further modify it to produce other molecular entities,”
J.A. 2146 at 135:16–19. These other molecular entities, as
found by the Board, include “the diethanolamine salt of
treprostinil,” J.A. 16, 37, which Phares identifies as “[a]
preferred embodiment.” J.A. 1359. The Board then went
a step further with its analysis and found that one of ordi-
nary skill would have had reason to combine Moriarty and
Phares because Phares improves the treprostinil taught by
Moriarty, as the Phares treprostinil diethanolamine “im-
proves at least the bioavailability[] of” Moriarty’s trepros-
tinil. J.A. 37. Both Phares itself and the Winkler Reply
Declaration support this conclusion. Dr. Winkler explains
that “as disclosed in Phares and well-known to a [person of
ordinary skill], forming [treprostinil diethanolamine]
would . . . improve the bioavailability of treprostinil.”
J.A. 1973–74 ¶ 97; see J.A. 1994–95 ¶ 128 (incorporating
analysis from J.A. 1973–75); J.A. 1433. Last, the Board
reasonably found “that [one of ordinary skill] would have
had a reason to eliminate the intermediate isolation step”
taught by Moriarty. J.A. 39. The Winkler Declaration
makes clear that “instead of isolating the neutral carbox-
ylic acid at this step by removal of the methanol, one could
instead add diethanolamine (i.e., a base) to the treprostinil
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solution so that removal of the methanol would instead
leave a salt, specifically, treprostinil diethanolamine salt.”
J.A. 942 ¶ 177 (citing J.A. 1390 (Phares)). As Dr. Winkler
elaborated, “a [person of ordinary skill] would understand
that an intermediate purification step should be unneces-
sary because not purifying the intermediate carboxylic acid
before addition of a base should not affect salt formation.”
J.A. 932–33 ¶ 151. This evidence amply supports each of
the Board’s findings that a person of ordinary skill would
have had a motivation to combine Moriarty and Phares.4
UTC next argues the Board erred because it relied on
“common sense” to “fill in a missing limitation.” Appel-
lant’s Br. 40. But UTC’s reliance on Arendi S.A.R.L. v. Ap-
ple Inc., 832 F.3d 1355 (Fed. Cir. 2016), to limit the use of
common sense in an obviousness analysis is misplaced be-
cause no claim limitation is missing from the prior art.
Here, both Moriarty and Phares disclose treprostinil in
4 Contrary to UTC’s contention, Dr. Winkler’s testi-
mony, including his expressed reasons why a person of or-
dinary skill would have had any motivation to combine, do
not need to be expressly lifted from the prior art. See KSR
Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406, 415, 418–22
(2007); DyStar Textilfarben GmbH & Co. Deutschland KG
v. C.H. Patrick Co., 464 F.3d 1356, 1361 (Fed. Cir. 2006)
(“[T]here is no requirement that the prior art contain an
express suggestion to combine known elements to achieve
the claimed invention. Rather, the suggestion to combine
may come from the prior art, as filtered through the
knowledge of one skilled in the art.” (citation omitted)).
The Board may properly rely on the knowledge of one of
ordinary skill in the art such as Dr. Winkler to help estab-
lish a motivation to combine. As the Board correctly notes,
this is especially true where the motivation is to enhance
commercial viability of a process. See Dystar, 464 F.3d
at 1367–68.
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solution and Phares further teaches contacting treprostinil
in solution with diethanolamine base to form a salt. Arendi
limited the application of “common sense” in an obvious-
ness analysis where, unlike here, a claim limitation was
missing in the prior art.5 Id. at 1361–63. By contrast, here
the Board invoked “common sense” to support, in part, its
motivation to combine analysis, not to conclude that a
claim limitation is satisfied by Petitioner’s combination.
See J.A. 38. In fact, the Arendi court acknowledged this
use of common sense was proper and, indeed, typical.
“[C]ommon sense is typically invoked to provide a known
motivation to combine, not to supply a missing claim limi-
tation.” Arendi, 832 F.3d at 1361.
Still, UTC posits that “common sense is being used to
fill in a missing limitation—the exclusion of intervening
isolation steps.” Appellant’s Br. 39. But the Board relied
on more than common sense. Dr. Winkler’s Reply Declara-
tion explains “that an ordinarily skilled artisan would have
had a reason to eliminate the intermediate isolation step,
‘thereby increasing synthetic efficiency and lowering pro-
duction costs for treprostinil diethanolamine salt.’” J.A. 39
(citing J.A. 2001–03 ¶¶ 140–44); see also J.A. 1976–78
¶¶ 101–03. At bottom, the “Board’s invocation of common
sense was properly accompanied by reasoned analysis and
evidentiary support” in the form of multiple “pages of
5 The Board concluded “that treprostinil is not iso-
lated from the solution formed in step (b) before forming a
salt in step (c)” because claim 1 is consisting of the recited
steps and itself “dictates that the solution formed in step
(b), and not treprostinil isolated from step (b), is the start-
ing material for forming a salt in step (c).” J.A. 27–28
(Claim Construction Section II.C.3). “Thus, Petitioner
must show . . . that the combined teachings of Moriarty
and Phares suggest to an ordinarily skilled artisan to skip
the intermediate isolation step.” J.A. 34 n.15.
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analysis” on the limitation and reliance on “detailed expert
testimony.” B/E Aerospace, Inc. v. C&D Zodiac, Inc,
962 F.3d 1373, 1380 (Fed. Cir. 2020).
CONCLUSION
We have considered UTC’s remaining arguments but
do not find them persuasive. For the reasons above, we
affirm the Board’s final written decision and its denial of
UTC’s motion to exclude the Winkler Declaration.
AFFIRMED
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