Case: 20-1098 Document: 40 Page: 1 Filed: 11/10/2020
United States Court of Appeals
for the Federal Circuit
______________________
FERRING B.V., FERRING INTERNATIONAL
CENTER SA, FERRING PHARMACEUTICALS INC.,
Plaintiffs-Appellants
v.
ALLERGAN, INC., ALLERGAN USA, INC.,
ALLERGAN SALES, LLC, SEYMOUR H. FEIN,
RONALD V. NARDI,
Defendants
SERENITY PHARMACEUTICALS CORPORATION,
SERENITY PHARMACEUTICALS, LLC, REPRISE
BIOPHARMACEUTICS, LLC,
Defendants-Appellees
______________________
2020-1098
______________________
Appeal from the United States District Court for the
Southern District of New York in No. 1:12-cv-02650-PKC,
Senior Judge P. Kevin Castel.
______________________
Decided: November 10, 2020
______________________
MARY W. BOURKE, Womble Bond Dickinson (US) LLP,
Wilmington, DE, argued for plaintiffs-appellants. Also rep-
resented by KRISTEN HEALEY CRAMER, DANA KATHRYN
SEVERANCE; JOHN W. COX, JOSHUA A. DAVIS, Atlanta, GA.
Case: 20-1098 Document: 40 Page: 2 Filed: 11/10/2020
2 FERRING B.V. v. ALLERGAN, INC.
SARAH ELIZABETH SPIRES, Skiermont Derby LLP, Dal-
las, TX, argued for defendants-appellees. Also represented
by PAUL SKIERMONT.
______________________
Before O’MALLEY, REYNA, and CHEN, Circuit Judges.
O’MALLEY, Circuit Judge.
When a district court enters judgment at the summary
judgment stage, it is at times difficult to discern on appeal
whether the nonmovant failed to raise sufficient factual
disputes to prevent judgment or the court acted despite
such disputes. Where the matter adjudged is a quintessen-
tially fact-laden one, such as the equitable matter at issue
here, it is especially important that we guard against a
rush to judgment. We conclude that such a rush to judg-
ment happened here. Accordingly, we vacate and remand
for further development of the record and a later-stage res-
olution of whether Appellants are equitably estopped from
seeking to correct inventorship of the patents at issue in
these proceedings.
BACKGROUND
I
Seymour Fein worked as a consultant for Ferring Phar-
maceuticals Inc. from December 1998 until the company
terminated his consulting agreement on November 7, 2002.
While Fein was consulting for Ferring Pharmaceuticals
Inc., he became involved in a Ferring 1 project involving
desmopressin. Desmopressin is a synthetic analog of the
naturally occurring hormone arginine vasopressin, which
1 We refer collectively to Appellants Ferring B.V.,
Ferring International Center SA, and Ferring Pharmaceu-
ticals Inc. collectively as “Ferring.”
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FERRING B.V. v. ALLERGAN, INC. 3
regulates the body’s retention of water. Among other
things, desmopressin is used to treat nocturia (disruption
of nighttime sleep due to the need to urinate).
As early as 1999, Ferring scientists Jens Peter
Nørgaard and Thomas Senderovitz were involved in a clin-
ical trial studying the bioavailability and pharmacokinet-
ics of desmopressin. The trial demonstrated that orally
administered desmopressin had a duration of action in the
range of six hours. A 2000 presentation authored by
Nørgaard acknowledged low bioavailability and high vari-
ation of absorption as known problems with using desmo-
pressin to treat nocturia, hypothesized that “[t]he need for
high plasma levels of desmopressin” to achieve an antidiu-
retic effect “is overestimated,” and suggested that in-
creased desmopressin doses may pose a safety issue.
S.A. 4431–32, 4435, 4455. 2 Ferring initiated a follow-on
study in October 2000, shepherded by Nørgaard and
Senderovitz, to model the desmopressin dose-response re-
lationship. The results of the follow-on study supported
their hypothesis that low doses and plasma concentrations
of desmopressin could be clinically effective.
As Fein recalls events, Ronald V. Nardi, a Ferring em-
ployee, approached him in 2001 seeking assistance with a
Ferring project involving clinical studies using a desmo-
pressin oral tablet to treat adult nocturia. Nardi sought
ideas from Fein regarding how to minimize the high inci-
dence of hyponatremia Ferring had observed in its clinical
trials. Hyponatremia is a condition in which sodium levels
in the blood fall to abnormally low levels, and can lead to
seizures, cardiac arrhythmias, cerebral edema, and death.
Fein recounts that, in August 2001, he suggested to Nardi
2 “S.A.” refers to the corrected supplemental appen-
dix filed by the parties on September 17, 2020. Corrected
Supplemental Appendix, Ferring B.V. v. Allergan, Inc.,
No. 20-1098 (Fed. Cir. Sept. 17, 2020), ECF No. 39.
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4 FERRING B.V. v. ALLERGAN, INC.
that hyponatremia could be reduced or avoided by using
lower dosages of desmopressin than Ferring had previously
tested, and that such dosages could be administered in a
waterless orodispersible form (a “melt”) sublingually
through the mucosal membranes of the mouth to improve
bioavailability of the desmopressin.
In March 2002, Nørgaard and Senderovitz began de-
signing additional clinical studies to test a new orodispersi-
ble form of desmopressin known within Ferring as
“NEWMIN.” By then, a study comparing NEWMIN to Fer-
ring’s previously marketed tablet had demonstrated that
the bioavailability of NEWMIN was approximately double
that of the previously marketed tablet. NEWMIN’s in-
creased bioavailability “open[ed] up the possibility of stud-
ying lower doses of desmopressin than currently
marketed.” J.A. 3632. By April 2002, Ferring had de-
signed a clinical study protocol, sponsored by Senderovitz
and designated CS007. CS007 would investigate the phar-
macokinetics and antidiuretic effect of orodispersible
desmopressin tablets containing five low doses of desmo-
pressin alongside a placebo.
In May 2002, Ferring filed Great Britain Patent Appli-
cation No. GB0210397.6 covering various dosage forms of
an orodispersible desmopressin formulation. Ferring’s ap-
plication includes a claim directed to “[a] pharmaceutical
dosage form of desmopressin adapted for sublingual ab-
sorption.” J.A. 286. The application does not list any in-
ventors.
When Ferring experienced delays in production of the
orodispersible tablets to be used in its CS007 study,
Nørgaard and Senderovitz planned another clinical study
to investigate the pharmacokinetic and antidiuretic effects
of various low desmopressin doses. The study was desig-
nated CS009 and used an intravenous desmopressin for-
mulation to approximate the CS007 orodispersible doses.
Fein did not participate in the design of the CS009 clinical
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FERRING B.V. v. ALLERGAN, INC. 5
study protocol. In June 2002, Fein was selected to oversee
United States operations of CS009. As part of that role,
Fein received via email a copy of Ferring’s CS009 clinical
study protocol. J.A. 3741. After reviewing the protocol,
Fein suggested certain changes, including converting the
original dose levels (expressed in nanograms) to doses on a
per-weight basis (nanograms per kilogram) to accommo-
date study participants within a greater weight range.
In September 2002, Ferring filed Application
No. PCT/IB02/04036 under the Patent Cooperation Treaty
(“PCT”), claiming priority from Ferring’s Great Britain ap-
plication. Ferring’s PCT application lists six inventors, in-
cluding Senderovitz, Fein, and Nardi. Fein and Nardi were
included as inventors based on Nardi’s representation that
they had conceived the sublingual route of administration.
Two months later, Ferring terminated Fein’s consulting
agreement.
II
From November 21, 2002 to December 14, 2004, Fein’s
attorney, William Speranza, corresponded with Ferring re-
garding Fein’s purportedly inventive contribution of the
sublingual administration route. We refer to the letters
and emails exchanged between Ferring and Speranza col-
lectively as “the Speranza correspondence.”
A letter from Speranza dated November 21, 2002 as-
serted that Fein invented material included in Ferring’s
PCT application, characterizing Fein’s contribution as “a
sublingual, transmucosal route of delivery which affords a
number of advantages . . . including enabling the effective
use of formulations having reduced concentrations of
desmopressin.” J.A. 531. The letter asserted that Fein had
no obligation to assign to Ferring any rights in inventions
Fein conceived while consulting for Ferring. Consequently,
Fein would have ownership rights in any patents that may
issue from Ferring’s PCT application. Speranza requested
that Ferring provide copies of all prosecution documents
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6 FERRING B.V. v. ALLERGAN, INC.
and any documents filed in subsequent national phase ap-
plications. Ferring and Speranza then exchanged several
letters regarding the events underlying Fein’s contribu-
tion. In January 2003, Speranza sent Ferring another let-
ter reiterating Fein’s “ownership rights in the invention,
the pending application therefor and any patents that may
issue on his invention.” J.A. 534. The letter renewed
Speranza’s request that Fein “be kept fully apprised” of the
status of Ferring’s PCT application. Id. Speranza also
raised the possibility that “it may be necessary for [Fein] to
take steps independent of Ferring as may be necessary to
protect his interests.” J.A. 534–35.
Ferring responded on April 9, 2003, advising Speranza
that it had “now taken the decision to drop the feature
‘adapted for sublingual administration.’” J.A. 537. Consid-
ering the prior art, Ferring found it “clear . . . that the fea-
ture does not in this context confer a delimitation i.e.
novelty.” Id. Accordingly, Ferring relayed that Fein would
“not be one of the designated inventors in the modified PCT
application to be filed.” Id.
Approximately one week later, on April 17, Speranza
sent an email to Ferring stating that Fein “ha[d] no funda-
mental problem with” Ferring’s decision to omit “the fea-
ture of sub-lingual administration invented by Dr. Fein.”
J.A. 539. Speranza stated that “Fein also is the inventor of
the associated low dosage possibilities enabled by the sub-
lingual administration route,” expressed Fein’s under-
standing that this was not “specifically claimed in the UK
application,” and noted his “assum[ption] that Ferring is
not pursuing that subject matter in the planned PCT fil-
ing.” Id. The email also informed Ferring that “Fein is
planning to himself proceed with pursuing patent protec-
tion covering the sub-lingual administration route and the
associated low dosage possibilities enabled by same which
he invented, all at his own expense going forward and with
the understanding that Ferring relinquishes any owner-
ship claims thereto.” Id. Finally, Speranza notified
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FERRING B.V. v. ALLERGAN, INC. 7
Ferring that Fein “plans to claim priority to [Ferring’s] UK
application,” and requested that Ferring provide “the par-
ticulars of the UK filing.” Id.
On April 29, 2003, Ferring responded, explaining that
it would not pursue patent protection for the invention de-
scribed by Speranza in his April 17 letter, because “[t]he
low dosage possibilities enabled by the sublingual admin-
istration route are already available in the public domain.”
J.A. 542. Ferring noted, however, that it “cannot of course
say now that Ferring will not make any claim as to owner-
ship of any other material Dr[.] Fein may include in any
patent application . . . without seeing the text.” Id. With-
out “knowing what claims for novelty or inventive steps
[Fein] ha[d] in mind,” Ferring cautioned that it “cannot be
sure that [Fein’s forthcoming application] does not cover
matters to which employees of the Ferring Group have con-
tributed or regarding which Dr[.] Fein is bound to [Ferring]
by terms of confidentiality.” Id. Ferring provided Fein
with the filing date and application number for its Great
Britain application, but refused to provide Fein with a copy
of the application, asserting that “Fein has no entitlement
to the patentable subject matter disclosed therein.” Id.
On May 6, 2003, Fein filed Application
No. PCT/US2003/014463, claiming priority from Ferring’s
Great Britain application and listing Fein as the sole in-
ventor. Fein’s application claims low-dose pharmaceutical
compositions comprising desmopressin and methods of
treating various conditions with such compositions.
Though some of Fein’s PCT application claims recite
desmopressin formulations adapted for various routes of
administration, none of his PCT application claims are lim-
ited to desmopressin formulations administered sublin-
gually.
The next day, Ferring filed a modified PCT application,
which was assigned Application No. PCT/IB03/02368. Fer-
ring’s modified application claims priority from Ferring’s
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8 FERRING B.V. v. ALLERGAN, INC.
Great Britain application and Ferring’s September 2002
PCT application and does not list Fein as an inventor or
contain claims directed to sublingual administration of
desmopressin. Ferring ultimately obtained U.S. Patent
Nos. 7,569,429 (“the ’429 patent”) and 7,947,654 (“the ’654
patent”) claiming priority from its Great Britain applica-
tion.
During 2003 and 2004, Fein conducted clinical studies
related to low-dose desmopressin. Relevant here, in Au-
gust 2003, Fein initiated a study designated CNF Desmo
PK200301, titled “A Cross-Over Study Investigating the
Antidiuretic Effects and Pharmacokinetics of Three Low
Doses of Desmopressin Administered via Intravenous In-
fusion for 2 Hours in Over-Hydrated Healthy Non-Smoking
Male and Female Volunteers.” J.A. 653. Fein’s CNF
Desmo PK200301 used substantially the same protocol as
Ferring’s CS009 clinical study. Compare J.A. 3823–26,
with J.A. 4153–56.
On November 12, 2003, Fein filed U.S. Patent Applica-
tion No. 10/706,100 (“the ’100 application”) as a continua-
tion-in-part of his May 2003 PCT application. Like Fein’s
PCT application, the ’100 application claims low-dose phar-
maceutical compositions comprising desmopressin and
methods of treating various conditions with such composi-
tions. J.A. 651. None of the ’100 application claims are
limited to desmopressin formulations administered sublin-
gually. Id. Fein’s May 2003 PCT application published on
May 21, 2004. His ’100 application published approxi-
mately two months later on July 15, and ultimately issued
on September 21, 2010 as
U.S. Patent No. 7,799,761 (“the
’761 patent”). The ’761 patent claims recite pharmaceuti-
cal compositions comprising varying low doses of desmo-
pressin administered by various routes of delivery. Some
dependent claims further require that the claimed desmo-
pressin doses establish a particular desmopressin
plasma/serum concentration range, or that that a particu-
lar desmopressin plasma/serum concentration range be
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FERRING B.V. v. ALLERGAN, INC. 9
maintained for a specified duration. None of the claims re-
cite pharmaceutical compositions limited to sublingual ad-
ministration.
On December 9, 2004, Ferring sent Speranza a letter
advising Speranza that Ferring was “truly surprised” that
Fein had proceeded with his May 2003 PCT application,
which “contain[s] an invention to which we believe he has
no entitlement and which in particular discloses infor-
mation confidential and proprietary to Ferring.” J.A. 544.
Ferring’s letter notified Speranza that it would “take all
necessary steps to protect its rights and interests but be-
fore taking formal legal action [Ferring] wish[ed] to give
[Fein] an opportunity to explain himself.”
Id. Ferring fur-
ther informed Speranza that if it “d[id] not receive a full
and satisfactory explanation within 14 days of this letter
[Ferring] will commence formal action.”
Id.
Speranza responded five days later, sending Ferring
two letters on December 14. The first letter reminded Fer-
ring that it had acknowledged Fein’s intent to proceed with
his own patent application. Speranza also posited three
possible reasons for Ferring’s assertion that Fein had “no
entitlement” to the invention in his published PCT appli-
cation. First, and “as would appear” from Ferring’s Decem-
ber 9 letter, Fein’s PCT “application ‘discloses information
confidential and proprietary to Ferring.’” J.A. 546. Sec-
ond, Ferring believes “that this low dosage invention of
Dr. Fein is simply not patentable because of prior art.”
Id.
Third, “Fein is not the inventor of the claimed low dose in-
vention and/or . . . Fein cannot assert ownership rights to
it.”
Id. Speranza expressed his opinion that “[o]ur dealings
and communications throughout 2003 made clear that Fer-
ring made no claim to low dosage desmopressin as its in-
vention.” J.A. 546–47. Despite the earlier communications
regarding claims involving the sublingual route of delivery,
Speranza made no mention of the use of a sublingual route
for the delivery of low dosages. To the extent Ferring’s al-
legation referred to misuse of confidential information,
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10 FERRING B.V. v. ALLERGAN, INC.
Speranza explained that “[w]hatever Ferring data is set
forth in Dr. Fein’s subject patent application comes solely
from the text of the UK priority application filed by Ferring
in May 2002, naming Dr. Fein as a co-inventor.” J.A. 547.
In closing, Speranza stated that he “trust[ed] this response
will put this matter to rest.”
Id. “[I]n view of the fact that
Ferring itself published over a year ago the allegedly ‘con-
fidential and proprietary’ information to which [Ferring’s]
letter refers,” Speranza deemed it “irresponsible for Fer-
ring to level such serious accusations at Dr. Fein and to
threaten immediate legal action based thereon.”
Id.
Speranza’s second December 14, 2004, letter to Ferring
focused on Ferring’s allegations of misuse of confidential
information. It acknowledged Ferring’s “apparent concern
with the content of Dr. Fein’s published applications” and
informed Ferring that Fein filed a continuation-in-part
U.S. patent application (i.e., the ’100 application) “which
has since published as U.S. Patent Application Publication
No. 2004/0138098, dated July 15, 2004, also directed to low
dose desmopressin.” J.A. 550. Speranza’s letter stated
that a copy of the ’100 application was included as an at-
tachment, but Ferring disputes that it ever received a copy
of the ’100 application. Referencing Example 8 and Figures
1–9 of the ’100 application, Speranza’s letter noted that the
’100 application “contains data beyond that included in the
original Ferring UK application,” which data “did not em-
anate from Ferring.” J.A. 551. This letter was Speranza’s
last communication with Ferring before Ferring filed suit
in April 2012.
With his patent applications pending, Fein took steps
to commercialize his invention. In 2006, Fein and Samuel
Herschkowitz formed Serenity Pharmaceuticals Corpora-
tion and Serenity Pharmaceuticals, LLC to raise funds to
cover the prosecution of Fein’s patents and pursue clinical
development. In late 2006, Fein founded Reprise Biophar-
maceutics, LLC, a holding company having five members.
Fein transferred to Reprise his intellectual property rights
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FERRING B.V. v. ALLERGAN, INC. 11
related to his claimed desmopressin invention. We refer to
Reprise, Serenity Pharmaceuticals Corporation, and Se-
renity Pharmaceuticals, LLC collectively as “Serenity.”
In May 2007, Fein filed U.S. Patent Application
No. 11/744,615 (“the ’615 application”) as a divisional of the
’100 application. The ’615 application published on Novem-
ber 15, 2007 and matured into
U.S. Patent No. 7,405,203
(“the ’203 patent”) on July 29, 2008. The ’203 patent claims
recite methods of administering low doses of desmopressin
by various routes of delivery to establish various desmo-
pressin plasma/serum concentration ranges. Some claims
further require that the plasma/serum concentration range
be maintained for a specified duration. None of the claims
recite sublingual administration of desmopressin.
In July 2008, Fein filed U.S. Patent Application
No. 12/173,074 (“the ’074 application”) as a continuation of
the ’615 application. The ’074 application published on
January 1, 2009 and issued as
U.S. Patent No. 7,579,321
(“the ’321 patent”) on August 25, 2009. The independent
claims of the ’321 patent recite methods of administering
low doses of desmopressin by various routes of delivery to
produce an antidiuretic effect or a particular urine osmo-
lality in a patient. Several claims of the ’321 patent further
require that the urine osmolality or antidiuretic effect be
maintained for a specified duration. Again, none of the
claims recite sublingual administration of desmopressin.
We refer to the ’203 patent, ’761 patent, and ’321 patent
collectively as “the Fein patents.”
By the end of 2008, Fein had conducted Phase I and
Phase II clinical studies of a low-dose desmopressin in-
tranasal spray adapted for transmucosal delivery. Fein
proceeded with Phase III clinical trials in 2009 and 2010.
On March 31, 2010, Serenity Pharmaceuticals, LLC and
Reprise entered into agreements with Allergan Sales, LLC,
Allergan USA, Inc., and Allergan, Inc. (collectively, “Aller-
gan”) to develop and commercialize a low-dose
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12 FERRING B.V. v. ALLERGAN, INC.
desmopressin intranasal spray, assigning all of their
desmopressin intellectual property rights to Allergan. As
part of the agreements, Reprise and Serenity Pharmaceu-
ticals, LLC warranted that there was no threat of litigation
from any third party regarding the Fein patents. Allergan
made a $43 million up-front payment to acquire the desmo-
pressin intellectual property rights.
On October 12, 2010, Ferring’s counsel filed a request
for reexamination of Fein’s ’203 patent, arguing that the
prior art rendered the independent claims anticipated or
obvious. The U.S. Patent and Trademark Office (“USPTO”)
rejected Ferring’s request for reexamination of the ’203 pa-
tent on January 19, 2011.
III
On April 5, 2012, Ferring filed a complaint in district
court asserting New York state law claims and claims for
correction of inventorship of the Fein patents under
35 U.S.C. § 256. The matter was assigned to District Judge
Robert Sweet. The complaint named Allergan, Serenity,
Fein, and Nardi as defendants (collectively, “Defendants”).
Ferring alleged that Ferring scientists Nørgaard and
Senderovitz should be substituted for Fein as the sole in-
ventors, or at least added as co-inventors, to the Fein pa-
tents. Ferring filed an amended complaint in August 2013.
Defendants answered Ferring’s amended complaint. Aller-
gan filed counterclaims to correct inventorship of Ferring’s
’429 and ’654 patents (which issued from Ferring’s modi-
fied PCT application), claiming that Fein should be named
as the sole inventor or as a joint inventor on those patents.
In April 2015, Allergan moved for summary judgment
that Ferring’s § 256 claims were barred by equitable estop-
pel, and the non-Allergan defendants joined in Allergan’s
motion. Several months later, in September 2015, the dis-
trict court granted Allergan’s motion for summary judg-
ment and dismissed Ferring’s § 256 claims.
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FERRING B.V. v. ALLERGAN, INC. 13
In considering Allergan’s summary judgment motion,
the district court decided as a threshold matter that con-
duct occurring before the issuance of the Fein patents could
give rise to equitable estoppel of Ferring’s claims for cor-
rection of inventorship. The district court then concluded
that Ferring’s inaction for over seven years following
Speranza’s December 2004 letters satisfied the misleading
conduct prong of equitable estoppel. When Ferring was
faced with Speranza’s reference “to ‘low dosage’ applica-
tions of desmopressin as Fein’s inventions,” the district
court reasoned, Ferring’s response “was not that the low-
dosage invention was Ferring’s intellectual property, but
that it was not patentable at all, and that Ferring would no
longer be pursuing claims directed toward it.” Ferring B.V.
v. Allergan, Inc.,
253 F. Supp. 3d 708, 718 (S.D.N.Y. 2015).
The district court found Ferring’s threat of “immediate le-
gal action with respect to [Fein’s PCT] application” mis-
leading, because “Ferring did not disagree or otherwise
challenge Mr. Speranza’s assertion that low dosage devel-
opment was Fein’s intellectual property,” despite the fact
that “Ferring was aware of two Fein patent applications
that include claims for low desmopressin doses and low
desmopressin plasma concentration levels.”
Id. Therefore,
the district court concluded, “Ferring’s present application
to correct inventorship contradicts its earlier position in
the Speranza correspondence.”
Id. The district court also
concluded that the reliance and prejudice prongs of equita-
ble estoppel were satisfied.
In June 2016, the district court denied Ferring’s motion
for a stay and for certification of judgment to allow Ferring
to appeal the equitable estoppel summary judgment ruling.
The non-Allergan defendants subsequently moved to be
substituted for Allergan as counterclaim plaintiffs, and the
district court granted that motion on September 14, 2017.
Following Judge Sweet’s passing, the action was reas-
signed to District Judge P. Kevin Castel, who refused to
reconsider Judge Sweet’s earlier rulings and proceeded to
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14 FERRING B.V. v. ALLERGAN, INC.
address the counterclaims for correction of inventorship of
Ferring’s ’429 and ’654 patents. Following a bench trial on
those counterclaims, the district court entered judgment in
favor of Ferring, refusing to add Fein to Ferring’s ’429 or
’654 patents as either the sole or a joint inventor. Final
judgment in this matter was entered on September 30,
2019. 3
Ferring appeals the district court’s September 2015 eq-
uitable estoppel decision. Serenity also appealed
Judge Castel’s September 2019 judgment on its counter-
claims, and we consolidated Ferring’s appeal with
3 Ferring points out that, at least as to Fein’s claim
of co-inventorship of Ferring’s ’429 and ’654 patents,
Judge Castel found Dr. Fein’s testimony not credible. Fer-
ring B.V. v. Allergan, Inc., No. 12-cv-2650,
2019 WL
6183501, at *11 (S.D.N.Y. Sept. 27, 2019). In the form of a
supplemental letter pursuant to Federal Rule of Appellate
Procedure 28(j), Ferring also brought to our attention that
another district court judge, Chief Judge Colleen
McMahon, also questioned Fein’s credibility regarding his
involvement with low-dose desmopressin formulations.
Ferring Pharm. Inc. v. Serenity Pharm., LLC,
No. 17-cv-09922,
2020 WL 4926458, at *63 (S.D.N.Y.
Aug. 21, 2020) (concluding, after bench trial in parallel pro-
ceeding involving the validity of the ’203 and ’321 patents
under
35 U.S.C. § 102(f), that “[c]ontrary to his absolutely
incredible testimony, Dr. Fein did not suggest the idea of a
‘low dose that is enabled [by sublingual administra-
tion]’ . . . to Dr. Norgaard and his colleagues at Ferring”
(second alteration in original) (citation omitted)).
While Fein has not moved to strike those references
and the conclusions reached by those judicial officers on
differently developed records, we must base our judgment
on what was—and was not—presented to Judge Sweet dur-
ing the summary judgment proceedings at issue here.
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FERRING B.V. v. ALLERGAN, INC. 15
Serenity’s appeal. We subsequently granted Serenity’s mo-
tion to dismiss its appeal, leaving Ferring’s appeal as the
only pending appeal. We have jurisdiction pursuant to
28 U.S.C. § 1295(a)(1).
DISCUSSION
On appeal, Ferring argues that the district court erred
by: considering conduct that preceded the issuance of the
Fein patents in the equitable estoppel analysis; resolving
disputed issues of fact in favor of Defendants; and ignoring
evidence of Defendants’ unclean hands. We address each
argument in turn.
I
Our review of a district court’s grant of summary judg-
ment of equitable estoppel proceeds in two steps. John
Bean Techs. Corp. v. Morris & Assocs., Inc.,
887 F.3d 1322,
1327 (Fed. Cir. 2018) (citing Scholle Corp. v. Blackhawk
Molding Co.,
133 F.3d 1469, 1471 (Fed. Cir. 1998)). First,
applying the law of the regional circuit (here, the Second
Circuit), we review whether there are genuine issues of ma-
terial fact. See Accenture Global Servs., GmbH v. Guide-
wire Software, Inc.,
728 F.3d 1336, 1340 (Fed. Cir. 2013)
(citing Teva Pharm. Indus. v. AstraZeneca Pharm. LP,
661 F.3d 1378, 1381 (Fed. Cir. 2011)); Fed. R. Civ. P. 56(a).
The Second Circuit reviews a grant of summary judgment
de novo, construing the evidence in the light most favorable
to the nonmoving party and drawing all reasonable infer-
ences in that party’s favor. Kuebel v. Black & Decker Inc.,
643 F.3d 352, 358 (2d Cir. 2011) (citation omitted). “Sec-
ond, we review the district court’s application of equitable
estoppel for abuse of discretion.” John Bean, 887 F.3d
at 1327 (citing Radio Sys. Corp. v. Lalor,
709 F.3d 1124,
1130 (Fed. Cir. 2013)).
II
Ferring first argues that “[t]he district court’s applica-
tion of equitable estoppel to Ferring’s claims for correction
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16 FERRING B.V. v. ALLERGAN, INC.
of inventorship under
35 U.S.C. § 256 prior to the issuance
of any patents is contrary to the plain language of the stat-
ute and this [c]ourt’s precedent.” Appellants’ Br. 28.
Stated more clearly, Ferring claims that, because its writ-
ten exchanges with Fein predated the issuance of the Fein
patents, those exchanges should not have been factored
into the court’s equitable estoppel analysis, leaving nothing
else upon which to predicate the judgment on Ferring’s
claims. During oral argument, however, Ferring conceded
that our decision in MCV, Inc. v. King-Seeley Thermos Co.,
870 F.2d 1568, 1572 (Fed. Cir. 1989), stands for the propo-
sition that a court may consider pre-issuance conduct in as-
sessing the application of equitable estoppel to § 256
claims, and that MCV remains good law. Oral Arg. at 1:48–
3:02, http://oralarguments.cafc.uscourts.gov/default.aspx?
fl=20-1098_09032020.mp3.
MCV applied a formulation of equitable estoppel that
included an element of “unreasonable and inexcusable de-
lay in filing suit.”
870 F.2d at 1571. This court subse-
quently overruled that aspect of the formulation in A.C.
Aukerman Co. v. R.L. Chaides Constr. Co.,
960 F.2d 1020,
1042 (Fed. Cir. 1992) (en banc), abrogated on other grounds
by SCA Hygiene Prods. Aktiebolag v. First Quality Baby
Prods., LLC,
137 S. Ct. 954, 959 (2017). See Aukerman,
960 F.2d at 1042 (“The test set out in Jamesbury [Corp.
v. Litton Industrial Products, Inc.,
839 F.2d 1544 (Fed. Cir.
1988))] confusingly intertwines the elements of laches and
equitable estoppel and is expressly overruled. Delay in fil-
ing suit may be evidence which influences the assessment
of whether the patentee’s conduct is misleading but it is not
a requirement of equitable estoppel.”). All other aspects of
the analysis in MCV, however, were left intact.
In MCV, we applied to a correction of inventorship
claim the rule from “infringement situations” that “an as-
sertion of right followed by silence on the part of the pa-
tentee may give rise to an estoppel if the patentee’s silence
is sufficiently misleading.”
870 F.2d at 1572. The putative
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FERRING B.V. v. ALLERGAN, INC. 17
co-inventor (and founder of MCV) “conferred with [pa-
tentee Halsey Taylor’s representative] on drafts of the
claims” and suggested that he be included as a co-inventor
on Halsey Taylor’s application.
Id. at 1569. When Halsey
Taylor “responded that company policy prohibited the
naming of non-employees on company patents,” MCV’s
founder replied that “the exclusive right to market the wa-
ter coolers was more valuable to MCV than patent rights,
and that he would ‘help[] in any way [h]e could to facilitate
the submission of the . . . patent.’”
Id. (alterations in orig-
inal). When things later soured between the parties with
respect to their marketing agreement, MCV brought a cor-
rection of inventorship claim.
Id. We affirmed the district
court’s grant of summary judgment that MCV was equita-
bly estopped from asserting a correction of inventorship
claim, noting that “MCV not only remained silent about co-
inventorship after [its founder’s] 1982 discussion with
[Halsey Taylor], but affirmatively represented to Halsey
Taylor that it would assist ‘in any way [it] could’ to obtain
the patent.”
Id. at 1572 (third alteration in original). Be-
cause MCV’s founder “knew Halsey Taylor was seeking a
patent, and knew what was being claimed,” we reasoned
that “it was incumbent upon him timely, explicitly and te-
naciously to apprise Halsey Taylor of his purported inven-
torship so it could be maturely considered.”
Id. at 1573.
Retreating from the per se rule it initially advanced,
Ferring then suggested that Radio Systems and John Bean
support a rule that “when the scope of the issued patents
[is] different than what was before the parties that led to
the alleged misleading conduct or inaction then the defense
of equitable estoppel cannot apply.” Oral Arg. at 2:47–3:45;
see Radio Sys.,
709 F.3d 1124; John Bean,
887 F.3d 1322.
Radio Systems does not stand for Ferring’s revised
rule, however. The two patents at issue in Radio Systems
differed in claim scope, but only the first-issued patent was
mentioned in a 2005 demand letter accusing Radio Sys-
tems’s predecessor of infringement. 709 F.3d at 1126,
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18 FERRING B.V. v. ALLERGAN, INC.
1131. Radio Systems’s predecessor responded that the
first-issued patent was invalid. Id. at 1126. The second
patent issued about two and a half years after the 2005 de-
mand letter. Id. There was no further communication be-
tween the parties until 2009, when Radio Systems received
a second demand letter accusing Radio Systems of infring-
ing both patents. Id. In 2010, Radio Systems filed an ac-
tion seeking declaratory judgment of noninfringement and
invalidity of both patents and the patent owner counter-
claimed for infringement of both patents. Id. at 1126–27.
The district court held that equitable estoppel barred the
patent owner’s infringement claims as to both patents
based on the 2005 demand letter and subsequent silence.
Id. at 1130. We affirmed the district court’s holding as to
the first patent, concluding that Radio Systems and its pre-
decessor were in privity and equitable estoppel applied to
Radio Systems as a successor-in-interest. Id. at 1131. We
then reversed the district court’s holding that equitable es-
toppel applied to bar the patent owner’s infringement
claims as to the second patent. Id. Because “[t]he first no-
tice of infringement to Radio Systems regarding the [sec-
ond] patent” occurred in the 2009 demand letter, there was
“simply no misleading conduct or silence by [the patent
owner] to indicate that it did not intend to enforce the [sec-
ond] patent against Radio Systems.” Id. Differences in
claim scope did not alone dictate the second of our conclu-
sions. It was the absence of any communication regarding
what became the claims in the second patent that was most
critical to our holding.
Nor does John Bean stand for a broad rule that equita-
ble estoppel does not apply whenever there is a difference
in scope between the issues implicated in discussions giv-
ing rise to potentially misleading conduct and the patent
claims at issue in subsequent litigation. In John Bean, the
reexamined claims that formed the basis of John Bean’s in-
fringement suit were “heavily amended” or added following
an ex parte reexamination twelve years after the
Case: 20-1098 Document: 40 Page: 19 Filed: 11/10/2020
FERRING B.V. v. ALLERGAN, INC. 19
defendant’s original demand letter (to which John Bean
never responded) challenging the validity of the asserted
patent. 887 F.3d at 1324–26. John Bean did not allege any
infringing activity occurring prior to the issuance of the
reexamination certificate. Id. at 1326. We concluded that
“[t]he district court abused its discretion by applying equi-
table estoppel to bar John Bean’s infringement action with-
out considering how the ex parte reexamination affected
the [asserted] patent claims.” Id. at 1329. Under the cir-
cumstances presented, we reasoned that John Bean nar-
rowed its claims during reexamination to such an extent
that the defendant’s invalidity analysis communicated in
the demand letter would not apply to John Bean’s reissued
claims. See id. at 1328. We did not announce a blanket
rule that any change to claim scope between the time of
communications giving rise to allegedly misleading con-
duct and the filing of a patent suit would preclude the ap-
plication of equitable estoppel.
As “equitable estoppel is not limited to a particular fac-
tual situation nor subject to resolution by simple or hard
and fast rules,” Aukerman,
960 F.2d at 1041, we decline to
adopt a bright-line rule that equitable estoppel cannot ap-
ply whenever the scope of the issued patent is different
than what the parties discussed in communications leading
to the allegedly misleading conduct. Thus, while differ-
ences in claim scope are relevant to the equitable estoppel
inquiry, their mere existence does not render pre-issuance
conduct or communications irrelevant.
While we reject Ferring’s bright-line rule with respect
to the relevance of pre-issuance communications, that does
not mean material differences in the potential patent
claims discussed pre-issuance and the claims that ulti-
mately issue need not be considered. And it, importantly,
does not mean that such differences may not give rise to
material issues of fact regarding the implications of any pe-
riod of silence following pre-issuance communications. We
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20 FERRING B.V. v. ALLERGAN, INC.
turn to that question in the context of Ferring’s second ar-
gument.
III
Ferring also asserts that, in granting Defendants’ mo-
tion for summary judgment, the district court improperly
resolved issues of fact in favor of Defendants. Ferring prin-
cipally argues that the district court erred in concluding
that Ferring engaged in misleading conduct because that
was not the only possible inference from the evidence. On
this point, we agree with Ferring.
A
In the “most common situation” giving rise to equitable
estoppel, “the patentee specifically objects to the activities
currently asserted as infringement in the suit and then
does not follow up for years.”
Id. at 1042. Equitable estop-
pel has three elements:
(1) the patentee engages in misleading conduct
that leads the accused infringer to reasonably infer
that the patentee does not intend to assert its pa-
tent against the accused infringer; (2) the accused
infringer relies on that conduct; and (3) as a result
of that reliance, the accused infringer would be ma-
terially prejudiced if the patentee is allowed to pro-
ceed with its infringement action.
John Bean, 887 F.3d at 1327 (citing Scholle,
133 F.3d
at 1471); see also Aukerman,
960 F.2d at 1041 (quoting
D.B. Dobbs, Handbook on the Law of Remedies § 2.3, at 42
(1973)). “To justify summary judgment of equitable estop-
pel, any inference that a patentee made a misleading com-
munication by omission or acquiescence ‘must be the only
possible inference from the evidence.’” SCA Hygiene Prods.
Aktiebolag v. First Quality Baby Prods., LLC,
767 F.3d
1339, 1350 (Fed. Cir. 2014) (quoting Aukerman,
960 F.2d
at 1044), vacated in part on other grounds,
137 S. Ct.
at 967.
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FERRING B.V. v. ALLERGAN, INC. 21
B
We agree with Ferring that the Speranza correspond-
ence is subject to interpretation and does not support the
single inference that Ferring, by its statements in the let-
ters and subsequent silence, acquiesced in Fein’s sole in-
ventorship of the material in the Fein patents, particularly
because the claims in those patents are not limited to, and
do not even mention, the sublingual route of delivery of
desmopressin. We conclude that the district court erred
when it concluded as a matter of law that “Ferring’s pre-
sent application to correct inventorship contradicts its ear-
lier position in the Speranza correspondence,” Ferring,
253 F. Supp. 3d at 718, and, accordingly, abused its discre-
tion in granting summary judgment of equitable estoppel.
1
The district court’s decision rested on the erroneous
view that the scope of the Speranza correspondence and the
scope of Fein’s application claims were commensurate with
the scope of Fein’s issued claims. The district court abused
its discretion by applying equitable estoppel to bar Fer-
ring’s § 256 claims because it failed to address material dif-
ferences in the scope of Fein’s issued patent claims as
compared to the invention described in the Speranza corre-
spondence and Fein’s application claims. See John Bean,
887 F.3d at 1329.
To be sure, the parties understood from the Speranza
correspondence that Ferring disavowed any ownership
claim to the sublingual, transmucosal route of delivery of
desmopressin and its associated low-dosage possibilities
that Fein identified as his invention in the Speranza corre-
spondence. When Fein advised Ferring that he intended
independently to pursue patent protection for “the sub-lin-
gual administration route and the associated low dosage
possibilities enabled by same,” J.A. 539, Ferring responded
that it “will not be pursuing this claim” because “[t]he low
dosage possibilities enabled by the sublingual
Case: 20-1098 Document: 40 Page: 22 Filed: 11/10/2020
22 FERRING B.V. v. ALLERGAN, INC.
administration route are already available in the public do-
main,” J.A. 542.
But, contrary to those representations to Ferring, Fein
did not pursue patent protection for claims limited to sub-
lingual (or transmucosal) administration of desmopressin.
Instead, Fein pursued claims untethered to sublingual ad-
ministration of desmopressin. E.g., J.A. 587–89. In fact,
most of Fein’s PCT application claims are untethered to
any route of administration. Most of Fein’s PCT applica-
tion claims cover pharmaceutical compositions comprising
various low doses of desmopressin, some of which are fur-
ther limited to require that the claimed pharmaceutical
composition is effective to establish various desmopressin
plasma/serum concentrations. Indeed, none of Fein’s PCT
or ’100 application claims and none of his issued claims are
limited to sublingual administration of desmopressin. See
’203 patent at col. 28, ll. 7–56; ’321 patent at col. 28, l. 34–
col. 30, l. 18; ’761 patent at col. 28, l. 39–col. 30, l. 19;
J.A. 587–89, 651. Very few of Fein’s PCT or ’100 applica-
tion claims and very few of his issued claims are limited to
a transmucosal route of administration. See id. Fein’s PCT
and ’100 application claims are a sweeping departure from
his sublingual low-dose desmopressin invention as he de-
scribed it to Ferring. Importantly, Fein sought patent pro-
tection for his claims despite Ferring’s prior warning to
him that Ferring could not “say now that Ferring will not
make any claim as to ownership of any other material Dr[.]
Fein may include in any patent application . . . without see-
ing the text.” J.A. 542. In view of Ferring’s representation
to Fein that it could not disclaim ownership of any material
beyond the sublingual administration route and associated
low-dose possibilities, a reasonable factfinder could con-
clude that it would have been unreasonable for Fein to in-
fer from Ferring’s pre-2004 communications that Ferring
intended to relinquish inventorship rights in the issued
claims of the Fein patents.
Case: 20-1098 Document: 40 Page: 23 Filed: 11/10/2020
FERRING B.V. v. ALLERGAN, INC. 23
Serenity argues that Ferring did acquiesce in Fein’s in-
ventorship of patent claims untethered to the sublingual
route of administration when it remained silent after
learning, in December 2004, “of exactly what [Fein] was
claiming—through the claims in his published PCT Appli-
cation and ’100 Application.” 4 Appellees’ Br. 32. The dis-
trict court agreed with Serenity, resting its decision that
Ferring engaged in misleading conduct in part on its deter-
mination that “[t]he low-dosage invention as described in
the PCT at issue in the Speranza correspondence is the
same subject matter detailed in the patents-in-suit, down
to the specific numerical quantity of desmopressin to be
used.” Ferring, 253 F. Supp. 3d at 718. The district court
implicitly concluded that Ferring had notice of the inven-
tion in Fein’s issued claims as of Ferring’s December 2004
letter, by virtue of that letter’s reference to Fein’s 2003 PCT
application.
4 Though Speranza’s second December 14, 2004 let-
ter states that Speranza included a copy of the ’100 appli-
cation with the letter, J.A. 550, Ferring argues that no copy
was ever provided, Reply 24. Regardless, our assessment
of Fein’s PCT application applies equally to the ’100 appli-
cation, because like Fein’s PCT application, the ’100 appli-
cation does not recite any claims with a duration of action
limitation. See J.A. 651.
There is no evidence that Ferring had notice of Fein’s
’615 application (filed in 2007) or his ’074 application (filed
in 2008), which matured into Fein’s method of treatment
patents. Indeed, the Speranza correspondence does not in-
dicate that Fein was pursuing any additional patents be-
yond those he expressly identified by application number.
On this record, a reasonable factfinder could conclude that
Ferring had no obligation or incentive to monitor patent
filings to identify any additional patent applications Fein
had chosen to prosecute.
Case: 20-1098 Document: 40 Page: 24 Filed: 11/10/2020
24 FERRING B.V. v. ALLERGAN, INC.
But that conclusion rested on an inadequate claim
scope analysis, particularly as to Fein’s issued claims con-
taining duration of action limitations. In discussing the
relative scope of Fein’s issued claims and the application
claims, the district court did not point to any claims. In-
stead, the district court stated only that “[t]he low-dosage
invention as described in the PCT at issue in the Speranza
correspondence is the same subject matter detailed in the
patents-in-suit, down to the specific numerical quantity of
desmopressin to be used.” Id. The district court’s conclu-
sion that the claim scope of Fein’s issued claims is the same
as that of his application claims fails to account for the fact
that most of Fein’s issued claims contain duration of action
limitations completely absent from Fein’s application
claims. Compare, e.g., ’203 patent at col. 28, ll. 7–56, with
J.A. 587–89. Ferring based its § 256 claims in part on the
very duration of action limitations the district court over-
looked. See, e.g., Complaint at 26–33, Ferring B.V. v. Al-
lergan, Inc., No. 12-cv-2650 (S.D.N.Y. Apr. 5, 2012), ECF
No. 1; J.A. 1155 (“Indeed, the ’203, ’321, and ’761 patents
claim the very . . . duration of action (around 4–6 hours)
that Dr. Norgaard and Dr. Senderovitz developed before
any of Fein’s alleged conversations with Nardi.”).
In the absence of notice to Ferring of Fein’s claim to
inventorship of the duration of action limitations, a reason-
able factfinder could find that Ferring did not mislead Fein
regarding Ferring’s claims of inventorship with respect to
any of Fein’s application claims or issued claims reciting a
duration of action limitation.
2
Setting aside the differences in scope between Fein’s
application claims and his issued claims, and the parties’
dispute as to whether Ferring ever received or reviewed a
copy of the ’100 application, we must vacate the district
court’s summary judgment of equitable estoppel because
the district court’s interpretation of the Speranza
Case: 20-1098 Document: 40 Page: 25 Filed: 11/10/2020
FERRING B.V. v. ALLERGAN, INC. 25
correspondence is not the only reasonable one. See SCA
Hygiene, 767 F.3d at 1350 (“To justify summary judgment
of equitable estoppel, any inference that a patentee made a
misleading communication by omission or acquiescence
‘must be the only possible inference from the evidence.’”
(quoting Aukerman,
960 F.2d at 1044)).
In December 2004, Ferring wrote to Fein expressing
surprise that Fein had proceeded with his PCT “application
containing an invention to which [Ferring] believe[s] he
has no entitlement and which in particular discloses infor-
mation confidential and proprietary to Ferring to which
Dr[.] Fein had confidential access during his agreement as
[a] consultant.” J.A. 544. Ferring’s letter provided an ex-
ample, noting that Ferring’s confidential results from its
CS004 study “appear virtually verbatim” on page 30 of
Fein’s PCT application.
Id. Ferring further informed Fein
that “Ferring will take all necessary steps to protect its
rights and interests,” and stated that Ferring would “com-
mence formal action” if it “d[id] not receive a full and satis-
factory explanation within 14 days.”
Id.
Serenity argues that Ferring’s December 2004 letter
stated concerns regarding both Fein’s use of Ferring’s con-
fidential information and Fein’s lack of inventorship inter-
est (i.e., lack of “entitlement”) in the invention in his
published PCT application. Though Serenity’s position is
not unreasonable, Ferring’s December 2004 letter could
also reasonably refer only to Ferring’s concerns regarding
Fein’s use of Ferring’s confidential information. A reason-
able factfinder could interpret Ferring’s use of the phrase
“and which in particular” to explain further the basis for
Ferring’s assertion that Fein had “no entitlement” to the
invention in his PCT application, rather than to state
Fein’s misuse of confidential information as a separate con-
cern from lack of “entitlement.”
Speranza’s December 2004 responses confirm that Fein
contemporaneously understood Ferring’s “no entitlement”
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26 FERRING B.V. v. ALLERGAN, INC.
assertion to lend itself to multiple reasonable interpreta-
tions. Indeed, Speranza’s first responsive letter “con-
fess[ed] to not entirely understanding” Ferring’s “no
entitlement” assertion and set forth three alternative in-
terpretations. J.A. 546. First, and “as would appear” from
Ferring’s December 2004 letter, Ferring’s “‘no entitlement’
statement relates to the assertion that the application ‘dis-
closes information confidential and proprietary to Fer-
ring.’”
Id. Second, Ferring’s “no entitlement” assertion
could “refer[] to the belief of Ferring that this low dosage
invention of Dr. Fein simply is not patentable because of
prior art, as was expressed in [Ferring’s] letter of 29 April
2003.”
Id. Third, Ferring’s “no entitlement” assertion
could be “somehow intended to suggest that Dr. Fein is not
the inventor of the claimed low dose invention and/or that
Dr. Fein cannot assert ownership rights to it.”
Id.
Elaborating on the third possibility, Speranza mischar-
acterized Ferring’s April 29, 2003 letter as “confirm[ing]
that Ferring would not be pursuing any claim with respect
to low dose desmopressin.” J.A. 547. In fact, in that letter,
Ferring explained only that it would not pursue claims di-
rected to “[t]he low dosage possibilities enabled by the sub-
lingual administration route.” J.A. 542 (emphasis added).
To the extent Speranza’s articulation of the third possibil-
ity gave rise to a duty for Ferring to respond, a reasonable
factfinder could find that Speranza’s blatant mischaracter-
ization of the scope of Ferring’s prior disclaimer relieved
Ferring of any such duty.
In finding that Ferring’s December 2004 threat of “im-
mediate legal action” and subsequent silence misled Fein
into thinking that Ferring had relinquished any inventor-
ship rights in the inventions claimed in Fein’s PCT and
’100 applications, the district court cast aside Speranza’s
first two interpretations of Ferring’s “no entitlement” as-
sertion in favor of the third. See Ferring, 253 F. Supp. 3d
at 718. As the third possibility bears the closest relation to
the inventorship dispute underlying Ferring’s subsequent
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FERRING B.V. v. ALLERGAN, INC. 27
§ 256 claims, the district court’s decision to credit the third
possibility over the first two drew an inference against Fer-
ring. This was improper at summary judgment, particu-
larly when the evidence shows that Fein believed the first
possibility to be the most likely. 5 See Kuebel,
643 F.3d
at 358 (explaining that at summary judgment, courts are
to “constru[e] the evidence in the light most favorable to
the nonmoving party”). In view of the varying reasonable
interpretations of the Speranza correspondence, we must
vacate the district court’s summary judgment of equitable
estoppel and remand for further proceedings. See SCA Hy-
giene, 767 F.3d at 1350.
IV
Finally, Ferring asserts that the district court erred in
deciding that Ferring was equitably estopped from assert-
ing its § 256 claims because the court failed to consider
“other evidence and facts respecting the equities of the par-
ties.” Appellants’ Br. 49 (quoting Aukerman,
960 F.2d
at 1043). Specifically, Ferring maintains that in assessing
Defendants’ unclean hands, the district court erred by ig-
noring evidence that Fein intentionally and deliberately
copied Ferring’s CS009 clinical study protocol for use in his
own clinical studies. While we have already concluded that
a remand is appropriate for other reasons, we address this
issue because it will remain live on remand.
“[T]he trial court must, even where the three elements
of equitable estoppel are established, take into considera-
tion any other evidence and facts respecting the equities of
the parties in exercising its discretion and deciding
whether to allow the defense of equitable estoppel to bar
the suit.” Aukerman, 690 F.2d at 1043. Indeed, “equitable
5 Having concluded that the district court erred in its
misleading conduct analysis, we do not address the parties’
arguments regarding reliance and prejudice.
Case: 20-1098 Document: 40 Page: 28 Filed: 11/10/2020
28 FERRING B.V. v. ALLERGAN, INC.
estoppel is not limited to a particular factual situation nor
subject to resolution by simple or hard and fast rules.” Id.
at 1041.
Ferring’s opposition to Defendants’ motion for sum-
mary judgment of equitable estoppel raised four bases to
support the argument that Defendants’ unclean hands
should preclude the district court from granting equitable
relief. Ferring asserted: (1) Defendants misrepresented
that Allergan had viewed the Speranza correspondence
when conducting its diligence review prior to investing in
Serenity and Reprise; (2) Defendants hired a third party to
recover confidential Ferring documents from Nardi’s com-
puter, which documents Ferring had previously deleted
pursuant to Nardi’s employment agreement; (3) Defend-
ants’ counsel organized meetings between defense wit-
nesses to coordinate their testimony, after which Fein
submitted a supplemental witness statement modifying his
testimony; and (4) Fein duplicated Ferring’s CS009 clinical
study protocol in his own CNF Desmo PK200301 clinical
study, misrepresented it as his own, and subsequently in-
cluded data from the study in the Fein patents as Exam-
ple 8. J.A. 1169–71. With respect to Fein’s copying,
Ferring further argued that Fein had misrepresented to
the USPTO in his patent applications that he had evalu-
ated pharmacokinetic parameters at each desmopressin
dose level. J.A. 1170, 1205–06. Ferring cited evidence that
Fein did not attempt to measure plasma/serum levels of
desmopressin in the CNF Desmo PK200301 study before
he filed his patent applications, because the plasma sam-
ples from the study were still in frozen storage as of No-
vember 2006. Id. (citing S.A. 4234).
Despite the district court’s statement that it “has also
considered and rejects Ferring’s unclean hands argu-
ments,” the court discussed only Ferring’s first three argu-
ments. Ferring, 253 F. Supp. 3d at 721. The district court’s
opinion does not mention Ferring’s CS009 study or Exam-
ple 8 of the Fein patents at all. This leaves us no basis to
Case: 20-1098 Document: 40 Page: 29 Filed: 11/10/2020
FERRING B.V. v. ALLERGAN, INC. 29
infer that the district court considered Ferring’s evidence
that Fein copied Ferring’s CS009 study and made related
misrepresentations to the USPTO. We therefore conclude
that the district court abused its discretion in granting
summary judgment of equitable estoppel because the court
failed to consider all relevant evidence regarding the equi-
ties of the parties. See Aukerman, 690 F.2d at 1043; Roth-
schild Connected Devices Innovations, LLC v. Guardian
Protection Servs., Inc.,
858 F.3d 1383, 1388 (Fed. Cir. 2017)
(“A district court abuses its discretion when, as here, it
‘fail[s] to conduct an adequate inquiry.’” (alteration in orig-
inal) (quoting Atl. Research Mktg. Sys., Inc. v. Troy,
659 F.3d 1345, 1360 (Fed. Cir. 2011))).
CONCLUSION
We have considered the parties’ remaining arguments
and do not find them persuasive. For the foregoing rea-
sons, we vacate the district court’s judgment and remand
for further proceedings consistent with this opinion.
VACATED AND REMANDED
COSTS
The parties shall bear their own costs.
