Document ID: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-19-01924/USCOURTS-ca13-19-01924-0/pdf.json

Parties Involved:
Eagle Pharmaceuticals Inc.
Appellant
Slayback Pharma LLC
Appellee

Document Text:

United States Court of Appeals 

for the Federal Circuit ______________________ 

EAGLE PHARMACEUTICALS INC.,

Plaintiff-Appellant

v.

SLAYBACK PHARMA LLC,

Defendant-Appellee

______________________ 

2019-1924

______________________ 

Appeal from the United States District Court for the 

District of Delaware in No. 1:18-cv-01953-CFC, United 

States District Judge Colm F. Connolly.

______________________ 

Decided: May 8, 2020

______________________ 

DANIEL BROWN, Latham & Watkins LLP, New York, 

NY, argued for plaintiff-appellant. Also represented by 

KENNETH G. SCHULER, MARC NATHAN ZUBICK, Chicago, IL; 

GREGORY SOBOLSKI, San Francisco, CA; GABRIEL BELL, 

Washington, DC. 

 CONSTANCE HUTTNER, Budd Larner, P.C., Short Hills, 

NJ, argued for defendant-appellee. Also represented by 

JAMES BARABAS, BETH C. FINKELSTEIN, ANDREW J. MILLER, 

Windels Marx Lane & Mittendorf LLP, Madison, NJ. 

 ______________________ 

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2 EAGLE PHARMACEUTICALS INC. v. SLAYBACK PHARMA LLC

Before O’MALLEY, REYNA, and CHEN, Circuit Judges.

REYNA, Circuit Judge.

Eagle Pharmaceuticals appeals a district court judgment of non-infringement on the pleadings. Eagle sued 

Slayback Pharma LLC for infringing four patents covering 

Eagle’s brand name bendamustine pharmaceutical product. Eagle argues that the district court committed two errors when it concluded that the dedication-disclosure 

doctrine barred Eagle’s claim of infringement under the 

doctrine of equivalents. First, Eagle contends that the district court erred when it concluded that the asserted patents disclose, but do not claim, ethanol—and therefore 

dedicated ethanol to the public. Second, Eagle contends

that the district court improperly applied the dedicationdisclosure doctrine at the pleadings stage, in the presence 

of factual disputes and without drawing all inferences in 

Eagle’s favor. Because we find no error in the district 

court’s judgment on the pleadings, we affirm. 

BACKGROUND

Eagle Pharmaceuticals Inc. (“Eagle”) filed suit in the

U.S. District Court for the District of Delaware accusing 

Slayback Pharma LLC (“Slayback”) of infringing four patents under the doctrine of equivalents.1 Eagle’s infringement claims stem from Slayback’s new drug application 

(“NDA”) for a generic version of Eagle’s branded bendamustine product, BELRAPZO®. J.A. 105. Bendamustine 

is used to treat chronic lymphocytic leukemia and indolent 

B-cell non-Hodgkin lymphoma. 

For purposes of this appeal, Eagle’s four asserted patents share essentially the same written description and all 

independent claims recite essentially the same limitations. 

1 Eagle asserted U.S. Patent Nos. 9,265,831; 

9,572,796; 9,572,797; and 10,010,533.

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The parties agree that Claim 1 of U.S. Patent No. 9,572,796

(“the ’796 patent”), shown below in relevant part, is representative.2 

1. A non-aqueous liquid composition comprising: 

bendamustine, or a pharmaceutically acceptable salt thereof; 

a pharmaceutically acceptable fluid comprising a mixture of polyethylene glycol and 

propylene glycol, wherein the ratio of polyethylene glycol to propylene glycol in the 

pharmaceutically acceptable fluid is from 

about 95:5 to about 50:50; and

a stabilizing amount of an antioxidant; 

. . . .

’796 patent at col. 13 ll. 22–35 (emphasis added). 

Slayback conceded that its generic product literally infringes all claim limitations except for the “pharmaceutically acceptable fluid” limitation. Eagle asserted that 

Slayback’s product infringes the “pharmaceutically acceptable fluid” limitation under the doctrine of equivalents. 

Specifically, Eagle asserted that the ethanol in Slayback’s 

product is insubstantially different from the propylene glycol (“PG”) in the claimed composition. 

On January 4, 2019, Slayback moved for a judgment of 

non-infringement on the pleadings under Federal Rule of 

Civil Procedure 12(c). Slayback argued that the disclosurededication doctrine barred Eagle’s claim of infringement

under the doctrine of equivalents because the asserted patents disclose, but do not claim, ethanol as an alternative 

solvent to PG. 

2 All citations are to U.S. Patent No. 9,572,796. 

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4 EAGLE PHARMACEUTICALS INC. v. SLAYBACK PHARMA LLC

The specification expressly and repeatedly identifies 

“ethanol” as an alternative “pharmaceutically acceptable 

fluid” to PG. ’796 patent at col. 1 ll. 60–64, col. 4 ll. 34–42,

43–48, col. 5 ll. 25–35, 38–50, col. 6 ll. 3–14, 31–65, col. 7 

ll. 1–8. For example, the Summary of the Invention discloses that:

In other aspects of the invention, the bendamustine-containing compositions include a) a 

pharmaceutically acceptable fluid which 

contains one or more of propylene glycol, ethanol, polyethylene glycol, benzyl alcohol and 

glycofurol, and b) a stabilizing amount of a 

chloride salt.

Id. at col. 1 ll. 60–64 (emphasis added). Likewise, the specification teaches that: 

Preferred pharmaceutically acceptable 

fluids include PG, PEG or ethanol in this embodiment of the invention.

Id. at col. 4 ll. 44–46 (emphasis added). 

Eagle opposed Slayback’s motion, arguing that the asserted patents do not disclose ethanol as an alternative to 

PG for the claimed embodiment that contains an antioxidant. J.A. 238. Eagle asserted that the specification only 

discloses ethanol when discussing unclaimed embodiments 

that contain chloride salt. Id. According to Eagle, a skilled 

artisan would thus “not understand the specification to 

teach ethanol as an alternative to propylene glycol in the 

claimed formulations.” J.A. 234.

In support of its opposition, Eagle submitted an expert 

declaration from Dr. Mansoor Amiji. Dr. Amiji opined that 

a skilled artisan would understand the specification to disclose three distinct categories of formulations that each 

contain different ingredients and work in different ways. 

Dr. Amiji opined that a skilled artisan “would not view the 

specific ethanol-containing formulations including chloride 

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salts as a disclosure that ethanol was specifically identified 

as an alternative to the claim limitation at issue in the asserted claims.” J.A. 260 ¶ 45. Slayback did not submit evidence to rebut Dr. Amiji’s testimony. 

On May 9, 2019, the district court granted Slayback’s 

motion for judgment of non-infringement on the pleadings. 

The court determined that “[t]he parties have not identified a claim construction dispute, and the written description of the asserted patents unambiguously and repeatedly 

identifies [ethanol] as an alternative to propylene glycol.” 

Eagle Pharm., Inc. v. Slayback Pharma LLC, 382 F. Supp. 

3d 341, 346 (D. Del. 2019). The court rejected Eagle’s attempt to “manufacture a factual dispute” and declined to 

consider the expert declaration of Dr. Amiji. Id. at 346, 346 

n.2. The court concluded that it had “sufficient context to 

decide a question of law—i.e., that the disclosure-dedication doctrine applies to bar Eagle’s claims for infringement 

under the doctrine of equivalents.” Id. at 346. 

Eagle timely appealed. We have jurisdiction under 

28 U.S.C. § 1295(a)(1).

ANALYSIS

We review the district court’s judgment on the pleadings under the law of the regional circuit, which in this case 

is the Third Circuit. Data Engine Techs. LLC v. Google 

LLC, 906 F.3d 999, 1007 (Fed. Cir. 2018). The Third Circuit reviews the grant of judgment on the pleadings de 

novo, “accept[ing] all of the allegations in the pleadings of 

the party against whom the motion is addressed as true 

and draw[ing] all reasonable inferences in favor of the nonmoving party.” Id. (quoting Allstate Prop. & Cas. Ins. Co. 

v. Squires, 667 F.3d 388, 390 (3d Cir. 2012)). In doing so, 

we “disregard rote recitals of the elements of a cause of action, legal conclusions, and mere conclusory statements.” 

James v. City of Wilkes-Barre, 700 F.3d 675, 679 (3d Cir. 

2012). Rule 12(c) judgment is appropriate when the moving party clearly establishes that there are “no material 

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6 EAGLE PHARMACEUTICALS INC. v. SLAYBACK PHARMA LLC

issues of fact, and that he or she is entitled to judgment as 

a matter of law.” DiCarlo v. St. Mary Hospital, 530 F.3d 

255, 259 (3d Cir. 2008); see FED. R. CIV. P. 12(c).

Under the doctrine of equivalents, “a product or process 

that does not literally infringe upon the express terms of a 

patent claim may nonetheless be found to infringe if there 

is ‘equivalence’ between the elements of the accused product or process and the claimed elements of the patented invention.” Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 

520 U.S. 17, 21, 29 (1997). The doctrine of equivalents prevents “the unscrupulous copyist [from] mak[ing] unimportant and insubstantial changes and substitutions in the 

patent which, though adding nothing, would be enough to 

take the copied matter outside the claim, and hence outside 

the reach of law.” Graver Tank & Mfg. Co. v. Linde Air 

Prods. Co., 339 U.S. 605, 607 (1950). The central question 

for infringement under the doctrine of equivalents is 

whether “the accused product or process contain[s] elements identical or equivalent to each claimed element of 

the patented invention.” Warner-Jenkinson, 520 U.S. at 

40.

The disclosure-dedication doctrine bars application of

the doctrine of equivalents. Johnson & Johnston Assoc. v. 

R.E. Servs., 285 F.3d 1046, 1054 (Fed. Cir. 2002) (en banc). 

It states that “when a patent drafter discloses but declines 

to claim subject matter, . . . this action dedicates the unclaimed subject matter to the public.” Id. By preventing a 

patentee from recapturing unclaimed subject matter, the 

disclosure-dedication doctrine reinforces “the primacy of 

the claims in defining the scope of the patentee’s exclusive 

right.” Id. To determine whether the disclosure-dedication 

doctrine applies in a given case, we ask whether the specification discloses unclaimed subject matter with “such 

specificity that one of ordinary skill in the art could identify 

the subject matter that had been disclosed and not 

claimed.” PSC Comput. Prods., Inc. v. Foxconn Int’l, Inc., 

355 F.3d 1353, 1360 (Fed. Cir. 2004). If the court concludes 

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that the inventor dedicated an alleged equivalent to the 

public, the patent owner cannot prevail on its doctrine of 

equivalents infringement claim based on that equivalent. 

Maxwell v. J. Baker, Inc., 86 F.3d 1098, 1108 (Fed. Cir. 

1996). 

This appeal centers on Eagle’s challenge to the merits 

and procedural aspects of the district court’s application of 

the disclosure-dedication doctrine. 

A.

Eagle first challenges the merits of the district court’s 

determination that the disclosure-dedication doctrine bars 

Eagle’s infringement claims under the doctrine of equivalents. Eagle contends, as it did below, that the disclosurededication doctrine does not apply because the asserted patents do not disclose ethanol as an alternative to PG for the 

claimed embodiment containing an antioxidant. 

Eagle contends that the asserted patents disclose three 

distinct “categories” of bendamustine formulations: 

(i) chloride salt formulations; (ii) antioxidant formulations; 

and (iii) dimethyl sulfoxide (“DMSO”) formulations. Appellant Br. 20. According to Eagle, a skilled artisan would 

recognize that the three separate categories “have separate 

ingredients[] and work in different ways.” Id. Eagle asserts that the specification only discloses ethanol as an alternative to PG when discussing the unclaimed chloride 

salt formulations; it never discloses ethanol as an alternative to PG when discussing the claimed antioxidant formulations. Id. at 4. As a result, Eagle concludes, a “skilled 

artisan would not understand that ethanol . . . is an alternative to PG in the separate, claimed ‘PEG/PG/antioxidant’ 

category of formulations.” Id. at 20. We disagree.

The disclosure-dedication doctrine does not require the 

specification to disclose the allegedly dedicated subject 

matter in an embodiment that exactly matches the claimed 

embodiment. Johnson, 285 F.3d at 1052. In Johnson, we 

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rejected this embodiment-level approach to the disclosurededication doctrine and denied the patentee’s attempt to 

avoid dedication by claiming that the disclosure occurred 

in an “alternative [embodiment] distinct from the claimed 

invention.” Id. Instead, we have held that the disclosurededication doctrine requires only that the specification disclose the unclaimed matter “as an alternative to the relevant claim limitation.” Pfizer, Inc. v. Teva Pharm. USA, 

Inc., 429 F.3d 1364, 1378 (Fed. Cir. 2005). 

We conclude that the asserted patents disclose ethanol 

as an alternative to PG in the “pharmaceutically acceptable fluid” claim limitation. The specification repeatedly 

identifies—without qualification—ethanol as an alternative pharmaceutically acceptable fluid. ’796 patent at col. 1 

ll. 60–64, col. 4 ll. 34–42, 43–48, col. 5 ll. 25–35, 38–50, col. 

6 ll. 3–14, 31–65, col. 7 ll. 1–8. Aside from the description 

of certain exemplary embodiments, nothing in the specification suggests that these repeated disclosures of ethanol 

are limited to certain formulations, or that they do not extend to the claimed formulation. 

Eagle asserts that, in Pfizer, we declined to apply the 

dedication-disclosure doctrine because the alleged alternative disclosed in the specification (microcrystalline cellulose) did not serve the same purpose (preventing 

hydrolysis) as the claimed “saccharide.” 429 F.3d at 1379 

(concluding that the disclosed microcrystalline cellulose 

“does not appear to relate to the claimed invention”). Eagle 

contends that the chloride salt category of formulations in 

the present case likewise “work[] by a different mechanism” than the claimed antioxidant formulations, and thus 

a skilled artisan would understand that ethanol does not 

relate to the claimed invention. Appellant Br. 30. We are 

not persuaded. 

In Pfizer, the claim limitation-at-issue recited a specific 

purpose: “a suitable amount of a saccharide to inhibit hydrolysis.” 429 F.3d at 1373, 1378 (emphasis added). The 

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asserted alternative, microcrystalline cellulose, was disclosed in the specification without any relation to hydrolysis. Id. As a result, we were “not convinced that one of 

ordinary skill in the art would come to the conclusion that 

the inventors have identified microcrystalline cellulose in 

that formulation as an alternative to a ‘saccharide’ that 

prevents hydrolysis.” Id. 

In this case, the claim limitation-at-issue has only one 

stated purpose: that the fluid be “pharmaceutically acceptable.” Unlike in Pfizer, the specification here repeatedly discloses ethanol as serving that purpose, i.e., the 

specification expressly discloses ethanol as a “pharmaceutically acceptable fluid.” E.g., ’796 patent at col. 1 ll. 60–

64, col. ll. 34–42, 43–48. We therefore hold that the asserted patents dedicated ethanol to the public by disclosing, but not claiming, ethanol as an alternative to PG in 

the “pharmaceutically acceptable solvent” claim limitation. 

As a result, we affirm the district court on this point.

B.

Eagle also challenges the district court’s judgment on 

procedural grounds. Eagle asserts that, at the time the district court entered judgment of non-infringement on the 

pleadings, a factual dispute existed: whether a skilled artisan would understand the specification to disclose ethanol as an alternative to PG in the claimed invention. Eagle 

argues that the district court erred by resolving that factual dispute at the pleadings stage without drawing all reasonable inferences in Eagle’s favor. Appellant Br. 46 

(citing Nalco Co. v. Chem-Mod, LLC, 883 F.3d 1337, 1349 

(Fed. Cir. 2018)). Specifically, Eagle argues that the district court was required to infer that a “skilled artisan 

would not have understood that ethanol was an alternative 

to PG in the claimed ‘PEG/PG/Antioxidant’ category of formulations.” Id. at 44. Eagle explains that the district court 

erred by improperly ignoring Dr. Amiji’s declaration, which 

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was “the best (and only) evidence of a skilled artisan’s understanding of [the] disclosure.” Id. at 45. 

As a preliminary matter, when ruling on a Rule 12(c) 

motion, district courts have discretion to consider evidence 

outside the complaint for purposes of deciding whether to

accept that evidence and convert the motion into one for 

summary judgment. Kulwicki v. Dawson, 969 F.2d 1454, 

1462 (3d Cir. 1992); see also 5C WRIGHT & MILLER, FED.

PRAC. & PROC. CIV. § 1371 (3d ed.) (“As is true of practice 

under Rule 12(b)(6), it is well-settled that it is within the 

district court’s discretion whether to accept extra-pleading 

matter on a motion for judgment on the pleadings and treat 

it as one for summary judgment or to reject it and maintain 

the character of the motion as one under Rule 12(c).”). We 

conclude that the district court did not abuse its discretion 

when it set aside Dr. Amiji’s declaration. The district court 

reviewed Dr. Amiji’s declaration and determined that it 

was merely an “attempt[] to manufacture a factual dispute.” Eagle, 382 F. Supp. 3d at 346. The district court 

also found that the patents themselves provided “sufficient 

context to decide” the legal issue at hand. Id. Eagle has 

not persuaded us otherwise. In opposing Slayback’s motion 

to dismiss, Eagle conceded that the district court’s “reliance 

on expert testimony would be improper at this preliminary 

[pleadings] stage.” J.A. 233. 

We find no error in the district court’s decision to grant 

judgment of non-infringement on the pleadings. The application of the disclosure-dedication doctrine is a question of 

law. Pfizer, 429 F.3d at 1378. Here the district court concluded that the patents themselves provided “sufficient 

context to decide a question of law, i.e., that the disclosurededication doctrine applies to bar Eagle’s claims for infringement under the doctrine of equivalents.” Eagle, 382 

F. Supp. 3d at 346. 

Expert testimony is not always required for a district 

court to determine how a skilled artisan would understand 

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a patent’s disclosure and claimed invention. Union Carbide Corp. v. Am. Can Co., 724 F.2d 1567, 1573 (Fed. Cir. 

1984) (stating that a patent’s disclosure may be “easily understandable without the need for expert explanatory testimony”). For example, in Amgen Inc. v. Coherus 

BioSciences Inc., we held that expert testimony was not 

necessary to understand whether a patent owner “clearly 

and unmistakably surrendered unclaimed [disclosure] during prosecution.” 931 F.3d 1154, 1160 (Fed. Cir. 2019) (affirming judgment of non-infringement on the pleadings 

because prosecution history precluded Amgen’s infringement allegations based on the doctrine of equivalents). We 

explained that “Amgen’s statements during prosecution,” 

on their face, showed that “a competitor would reasonably 

believe that Amgen surrendered unclaimed salt combinations” as a matter of law. Id. (internal quotations omitted). 

Here, we conclude that the only reasonable inference 

that can be made from the patent disclosures is that a 

skilled artisan would understand the patents to disclose 

ethanol as an alternative to the claimed PG. Nothing in 

the record permits us to infer that a skilled artisan “would 

have understood that the patent specification describes distinct categories of formulations that contain different ingredients and work in different ways.” Appellant Br. 44. 

As a result, even when viewing the pleadings in the light 

most favorable to Eagle, we conclude there is no material 

issue of fact to resolve and Slayback is entitled to judgment 

in its favor as a matter of law. 

CONCLUSION

We have considered Eagle’s other arguments and find 

them unpersuasive. We affirm the district court’s judgment of non-infringement on the pleadings. 

AFFIRMED

COSTS

No costs.

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