United States Court of Appeals 

for the Federal Circuit ______________________

FOREST LABORATORIES, LLC, FKA FOREST 

LABORATORIES, INC., FOREST LABORATORIES 

HOLDINGS LTD.,

Plaintiffs-Cross-Appellants

v.

SIGMAPHARM LABORATORIES, LLC,

Defendant-Appellee

HIKMA PHARMACEUTICALS LLC, HIKMA 

PHARMACEUTICALS PLC, HIKMA 

PHARMACEUTICALS USA INC., FKA WEST-WARD 

PHARMACEUTICALS CORP., BRECKENRIDGE 

PHARMACEUTICAL INC., ALEMBIC 

PHARMACEUTICALS LTD., ALEMBIC GLOBAL 

HOLDING S.A., ALEMBIC PHARMACEUTICALS 

INC., AMNEAL PHARMACEUTICALS LLC, 

AMNEAL PHARMACEUTICALS OF NEW YORK 

LLC, AMNEAL PHARMACEUTICALS CO. INDIA 

PVT. LTD.,

Defendants-Appellants

______________________

2017-2369, 2017-2370, 2017-2372, 2017-2373, 2017-2374, 

2017-2375, 2017-2376, 2017-2389, 2017-2412, 2017-2436, 

2017-2438, 2017-2440, 2017-2441

______________________

Appeals from the United States District Court for the 

District of Delaware in Nos. 1:14-cv-01119-MSG, 1:14-cv-
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01266-SLR-SRF, 1:14-cv-01504-SLR-SRF, 1:15-cv-00158-

SLR, 1:15-cv-00430-SLR, Judge Sue L. Robinson.

______________________

Decided: March 14, 2019

______________________

HOWARD WARREN LEVINE, Finnegan, Henderson, 

Farabow, Garrett & Dunner, LLP, Washington, DC, argued for plaintiffs-cross-appellants. Also represented by 

JONATHAN ROBERT DAVIES, SANYA SUKDUANG; CHARLES E.

LIPSEY, Reston, VA. 

 ANTHONY R. FRIEDMAN, The Simon Law Firm, P.C., St. 

Louis, MO, argued for defendant-appellee. Also represented by ANTHONY G. SIMON. 

CLIFFORD KATZ, Kelley Drye & Warren, LLP, New York, 

NY, argued for all defendants-appellants. Defendant-appellant Breckenridge Pharmaceutical Inc. also represented 

by MALAVIKA RAO. 

 IMRON T. ALY, Schiff Hardin LLP, Chicago, IL, for defendants-appellants Hikma Pharmaceuticals LLC, Hikma 

Pharmaceuticals PLC, Hikma Pharmaceuticals USA Inc. 

Also represented by JOEL M. WALLACE. 

 

 KSENIA TAKHISTOVA, Hunton Andrews Kurth LLP, 

New York, NY, for defendants-appellants Alembic Pharmaceuticals Ltd., Alembic Global Holding S.A., Alembic 

Pharmaceuticals Inc. 

 MICHAEL R. DZWONCZYK, Sughrue Mion PLLC, Washington, DC, for defendants-appellants Amneal Pharmaceuticals LLC, Amneal Pharmaceuticals of New York LLC, 

Amneal Pharmaceuticals Co. India Pvt. Ltd. 

 ______________________
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Before PROST, Chief Judge, DYK and MOORE, Circuit 

Judges.

MOORE, Circuit Judge.

Sigmapharm Laboratories, LLC, (“Sigmapharm”), 

Hikma Pharmaceuticals LLC, Hikma Pharmaceuticals 

PLC, Hikma Pharmaceuticals USA Inc., (collectively,

“Hikma”), Breckenridge Pharmaceuticals Inc. (“Breckenridge”), Alembic Pharmaceuticals Ltd., Alembic Global 

Holdings S.A., Alembic Pharmaceuticals Inc., (collectively,

“Alembic”), Amneal Pharmaceuticals LLC, and Amneal 

Pharmaceuticals Co. India Pvt. Ltd. (collectively “Amneal”) 

are drug manufacturers who filed Abbreviated New Drug 

Applications with the Food and Drug Administration seeking to market generic versions of Saphris, a drug product 

sold by Forest Laboratories, LLC. Saphris is a sublingually 

administered, atypical antipsychotic containing asenapine 

maleate. 

Forest sued for patent infringement, asserting that Appellants’ proposed generic products would infringe claims 

1–2, 4–6, and 9–10 of U.S. Patent No. 5,763,476. The parties have stipulated that the validity of claims 2, 5, and 6 

rises and falls with that of claim 1, and the validity of 

claims 9 and 10 rises and falls with that of claim 4. Forest, 

Breckenridge, and Alembic have further stipulated that infringement of claims 9 and 10 rises and falls with that of 

claim 4. Claims 1 and 4 recite:

1. A pharmaceutical composition comprising as a 

medicinally active compound: trans-5-chloro-2-methyl-2,3,3a, 12b-tetrahydro-1H-dibenz[2,3:6,7]oxepino[4,5-c]pyrrole or a pharmaceutically 

acceptable salt thereof; wherein the composition is 

a solid composition and disintegrates within 30 seconds in water at 37° C.

4. A method for treating tension, excitation, anxiety, and psychotic and schizophrenic disorders, 
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comprising administering sublingually or buccally 

an effective amount of a pharmaceutical composition comprising trans-5-chloro-2-methyl-2,3,3a, 

12b-tetrahydro-1H-dibenz[2,3:6,7]oxepino[4,5-

c]pyrrole or a pharmaceutically acceptable salt 

thereof.

Trans-5-chloro-2-methyl-2,3,3a,12b-tetrahydro-1H-dibenz

[2,3:6,7]oxepino[4,5-c]pyrrole is also known as asenapine. 

Forest sells an atypical antipsychotic containing asenapine 

maleate under the name Saphris, which was developed by

non-party Organon, another pharmaceutical company. 

Asenapine was originally developed as a conventional oral 

tablet. Conventional oral tablets are swallowed and enter 

into the digestive system before being metabolized. In contrast, Saphris is administered sublingually, meaning the 

formulation is placed under the tongue, where it dissolves. 

Buccal administration is similar, but in the cheek cavity.

Following a bench trial, the district court held Appellants had not established claims 1–2, 4–6, and 9–10 to be 

invalid and held Forest had not established infringement 

of claims 4, 9, and 10 as to Alembic and Breckenridge. Appellants appeal the district court’s construction of claim 1 

and its determination that the claims have not been established to be invalid. Forest cross-appeals, arguing the district court’s finding that Breckenridge and Alembic do not 

infringe claim 4 was clearly erroneous. We have jurisdiction under 28 U.S.C. § 1295(a)(1). We vacate and remand 

the district court’s validity determination, and we vacate

and remand for it to reconsider infringement under a corrected claim construction.

DISCUSSION

I. Construction of Claim 1

While claim 4 is expressly limited to sublingual or buccal formulations of asenapine, claim 1 is not and instead 
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states that “the composition is a solid composition and disintegrates within 30 seconds in water at 37° C.” The district court nevertheless construed claim 1 to be limited to 

buccal and sublingual formulations. Appellants argue the 

district court erred in construing claim 1 this way. We review a district court’s ultimate claim construction and its 

interpretations of intrinsic evidence de novo and any subsidiary fact findings about extrinsic evidence for clear error. CardSoft, (Assignment for the Benefit of Creditors), 

LLC v. VeriFone, Inc., 807 F.3d 1346, 1348 (Fed. Cir. 2015).

We see no error in the district court’s construction. Although claim 1 does not expressly refer to buccal or sublingual administration, the claims “must be read in view of 

the specification, of which they are a part.” Phillips v. 

AWH Corp., 415 F.3d 1303, 1315 (Fed. Cir. 2005) (en banc)

(quoting Markman v. Westview Instruments, Inc., 52 F.3d 

967, 979 (Fed. Cir. 1995)). “When a patent . . . describes

the features of the ‘present invention’ as a whole, this description limits the scope of the invention.” Verizon Servs. 

Corp. v. Vonage Holdings Corp., 503 F.3d 1295, 1308 (Fed. 

Cir. 2007). Here, the ’476 patent states “[t]he invention relates to a sublingual or buccal pharmaceutical composition,” ’476 patent at 1:6–7, strongly supporting the district 

court’s construction. See also id. at 1:33–36. That construction is further supported by additional language in 

the specification, which explains the benefits of sublingual 

and buccal treatment over the prior art. Id. at 1:33–34

(“The invention therefore relates to a sublingual or buccal 

pharmaceutical composition . . . .”). The patent is also expressly titled “Sublingual or Buccal Pharmaceutical Composition.” See, e.g., UltimatePointer, L.L.C. v. Nintendo 

Co., 816 F.3d 816, 823 (Fed. Cir. 2016) (using patent title 

to inform claim construction). Additionally, the claim language “disintegrates within 30 seconds in water at 37° C”

appears in the ’476 patent as the definition of “[r]apid disintegration.” ’476 patent at 1:59–61. The specification 

states that “[p]referred pharmaceutical compositions are 
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solid pharmaceutical compositions which rapidly disintegrate in the mouth of a subject, upon insertion into the buccal pouch or upon placement under the tongue.” Id. at 

1:56–59. This strongly suggests that the language “the 

composition is a solid composition and disintegrates within 

30 seconds in water at 37° C” was meant to limit the claim 

to buccal and sublingual formulations.

Appellants suggest that this improperly reads a 

method step into the claim by requiring a particular 

method of administration, namely sublingual or buccal.

The specification, however, repeatedly uses “sublingual or 

buccal” to modify “composition,” indicating that these are 

properties of the composition itself. See, e.g., Id. at 1:6–7.

We have considered Appellants’ remaining arguments 

as to claim construction and find them unpersuasive.1 

Given the claim language and the language in the specification, we hold the district court properly construed 

claim 1 to be limited to buccal and sublingual formulations. 

We do not, therefore, reach Appellants’ validity challenges 

based on its proposed alternative construction.

II. Obviousness

Following a bench trial, the district court concluded 

claims 1 and 4 would not have been obvious. While it is 

undisputed that both oral formulations of asenapine and 

sublingual formulations of other drugs were known in the 

 

1 Although Appellants now argue this construction 

renders the claim indefinite, this argument has been 

waived. The section of their post-trial briefing in which 

Appellants argue they raised this issue below nowhere 

mentions indefiniteness. J.A. 3325–35. Instead, it only 

mentions § 112, the statutory basis for the definiteness 

challenge, in a parenthetical to the fourth case cited in a 

string citation. Id. This is insufficient to preserve the argument.
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prior art, the district court found that there was no motivation in the art to develop sublingual or buccal formulations of asenapine. It found the resolution of the 

cardiotoxic effects by sublingual administration was an unexpected result. It found sublingual administration met a 

long-felt need for a safe, effective, and tolerable atypical 

antipsychotic useful to treat schizophrenia and mania.

Obviousness is a question of law with underlying facts. 

Par Pharm. Inc. v. TWI Pharm., Inc., 773 F.3d 1186, 1193

(Fed. Cir. 2014). After a bench trial, we review the district 

court’s conclusion of obviousness de novo and the underlying factual findings for clear error. Id. at 1194.

A. Motivation to Combine

The district court found Appellants had not established 

that there was a motivation to combine asenapine maleate 

into a sublingual or buccal form, and even if there were a 

motivation to combine, a skilled artisan would not have 

had a reasonable expectation that it would work. Whether 

there was a motivation to combine prior art references is a 

question of fact. Arctic Cat Inc. v. Bombardier Recreational 

Prods. Inc., 876 F.3d 1350, 1359 (Fed. Cir. 2017). We review for clear error.

An invention is not obvious simply because all of the 

claimed limitations were known in the prior art at the time 

of the invention. Instead, we ask “whether there is a reason, suggestion, or motivation in the prior art that would 

lead one of ordinary skill in the art to combine the references, and that would also suggest a reasonable likelihood 

of success.” Smiths Indus. Med. Sys., Inc. v. Vital Signs, 

Inc., 183 F.3d 1347, 1356 (Fed. Cir. 1999). The motivation 

“can be found explicitly or implicitly in the prior art references themselves, in market forces, in design incentives, or 

in ‘any need or problem known in the field of endeavor at 

the time of invention and addressed by the patent.’” Arctic 

Cat, 876 F.3d at 1359 (quoting KSR Int’l Co. v. Teleflex Inc., 

550 U.S. 398, 420–21 (2007)).
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At trial, Appellants’ primary and dominant argument 

as to motivation to combine was an alleged bioavailability 

concern with orally administered asenapine. The district 

court extensively considered this argument and rejected it. 

On appeal, Appellants have dispensed with their bioavailability argument and instead focus on two other claimed

motivations. First, they argue an ordinarily skilled artisan 

would have been motivated to administer asenapine maleate sublingually or buccally to address known compliance 

concerns. Second, they argue an ordinarily skilled artisan 

would have been motivated to administer asenapine maleate sublingually or buccally to obtain more treatment options. 

Appellants argue that an ordinarily skilled artisan 

would have been motivated to administer asenapine maleate sublingually or buccally to address compliance problems and swallowing difficulties in special patient 

populations. The district court discussed compliance concerns and, citing testimony from Forest’s expert witness 

Dr. McIntyre, explained that “clinicians with experience in 

treating schizophrenic patients understand that sublingual dosage forms are more burdensome to schizophrenic 

patients in that they require the patient to hold the dosage 

form in the mouth under the tongue for a period of time, 

and also require that the patient refrain from drinking or 

swallowing for a period of time.” J.A. 73 (citing J.A. 592–

93). The court further explained that Appellants’ “own expert clinician, Dr. Hollander, agreed that sublingual administration would not improve patient compliance.” 

J.A. 73 (citing J.A. 442–43). Summarizing testimony, however, is not a clear finding. Our review would be aided by

an express finding regarding whether compliance concerns 

regarding patients with swallowing difficulties would provide a motivation to combine. 

Turning to Appellants’ second claimed motivation, we 

hold that the district court did not clearly err in rejecting 

Appellants’ contention that the benefits of having multiple 
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treatment options available would provide a motivation to 

combine. In assessing whether there was a long-felt need, 

the district court found that “skilled artisans recognized 

the benefit of having multiple treatment options.” J.A. 76. 

Appellants further argue that their expert Dr. Hollander 

testified that there was a need for additional treatment options because no single product is appropriate for all patient populations and that in 1994, many antipsychotics 

were on the market in multiple forms. The district court 

did not clearly err, however, in concluding that a generic 

need for more antipsychotic treatment options did not provide a motivation to combine these particular prior art elements.

Appellants argue the district court ignored general 

suggestions in the prior art indicating a growing interest 

in sublingual and buccal formulations at the time of filing. 

The district court was presented with a variety of documentary evidence and testimony as to the state of the prior art. 

We see no clear error in its weighing of this evidence.

Finally, Appellants suggest that the district court erred 

in treating the claimed invention as providing a solution to 

an unrecognized problem in the art. We have recognized 

that where a problem was not known in the art, the solution to that problem may not be obvious, because “ordinary 

artisans would not have thought to try at all because they 

would not have recognized the problem.” Leo Pharm. 

Prods., Ltd. v. Rea, 726 F.3d 1346, 1357 (Fed. Cir. 2013).

The district court characterized the inventors’ discovery as a recognition of an unknown problem in the art in 

conjunction with the discovery of the solution to that problem. J.A. 69–70. It found that the Organon scientists discovered a “previously unknown” problem and developed the 

claimed sublingual dosage forms as a solution to that problem. Specifically, it found that during early clinical studies 

Organon discovered intravenous and oral administration of 
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asenapine resulted in severe cardiotoxic events. As a result, those studies were terminated prior to completion. 

The district court found, however, that during subsequent 

testing on beagles, while there was “a clear trend of increased heart effects with an oral tablet,” “no such trend 

was observed with the sublingual forms.” J.A. 44–45. The 

district court found that while Organon became aware of 

these problems, “[t]here was nothing in the prior art that 

would have indicated that the oral tablet had problems.” 

J.A. 68. 

The district court further held that the solution Organon developed to address the cardiotoxic effect was also 

non-obvious. It found that Organon’s data indicated that 

the cardiotoxic effect was likely caused by asenapine itself. 

J.A. 69. During conventional oral administration, asenapine undergoes first-pass metabolism, which processes the 

parent compound asenapine into metabolites. J.A. 69. In 

contrast, sublingual administration increases the amount 

of the parent compound by circumventing first-pass metabolism. J.A. 69. The district court held, therefore, that it 

would not have been predictable or expected that sublingual administration would provide a solution to the problem of cardiotoxic effects. J.A. 69–70.

Appellants object to this reasoning, arguing that the 

only reason the cardiotoxicity issue was not publicly known 

was because Organon concealed and misrepresented the 

events suffered by patients in clinical studies when it reported the results of those studies. While the actions alleged may raise a variety of concerns, we do not see how 

they affect the district court’s obviousness analysis. Ultimately, we see no clear error in the district court’s consideration of the unknown nature of the problem solved by the 

inventors and the factors that would teach away from their 

solution.

We have considered Appellants’ remaining arguments 

as to motivation to combine and find them unpersuasive. 
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However, in light of the district court’s failure to make an 

express finding as to whether compliance concerns for patients with trouble swallowing would provide a motivation 

to combine, we remand for the district court to address this 

question.

B. Long-Felt Need

“Evidence of a long felt but unresolved need tends to 

show non-obviousness because it is reasonable to infer that 

the need would have not persisted had the solution been 

obvious.” WBIP, LLC v. Kohler Co., 829 F.3d 1317, 1332 

(Fed. Cir. 2016). Whether or not such a long-felt need existed is a question of fact. Bristol-Myers Squibb Co. v. Teva 

Pharm. USA, Inc., 752 F.3d 967, 978 (Fed. Cir. 2014).

The district court found that at the time of the invention, there was a long-felt, but unmet, need for “a safe, effective, and tolerable atypical antipsychotic useful to treat 

schizophrenia and mania.” J.A. 76. In doing so, it found 

that prior to 1994, “typical antipsychotics were the primary 

therapeutic options for treating schizophrenia and mania.” 

J.A. 75. It noted, however, that typical antipsychotics “possessed debilitating side effects” and “a significant number 

of patients did not respond to treatment.” J.A. 75. As of 

1994, there were also two atypical antipsychotics available. 

J.A. 75. One “require[d] constant blood monitoring” and

had a “life-threatening side effect.” J.A. 75. The other had 

a variety of side effects that resulted in a discontinuation 

rate of around 74%. J.A. 75–76. Accordingly, the district 

court found that ordinarily skilled artisans “recognized the 

need for additional antipsychotic drugs” with improved 

side effect profiles. J.A. 76. It further found asenapine met 

this profile. J.A. 76.

Appellants point to evidence that they argue indicates

the claimed invention did not satisfy a long-felt but unmet 

need. Specifically, they argue there were a variety of antipsychotic drugs available at the time of the invention, there 
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is evidence that physicians did not switch treatment preferences for patients with schizophrenia when Saphris entered the market, and there is evidence that Saphris did 

not have better efficacy or compliance than other antipsychotics available in 1994. They further argue Saphris itself 

has many side effects and a high discontinuation rate. 

They argue the district court’s comparison of Saphris with 

the two other atypical antipsychotics, clozapine and risperidone, ignored evidence that clozapine treated the negative 

symptoms of schizophrenia, which Saphris does not; that 

both drugs were superior to Saphris in terms of efficacy and 

side effects; and that both drugs had much lower all-cause 

discontinuation rates than Saphris. 

In reviewing the district court’s fact findings, we do not 

ask whether evidence could have supported the opposing 

view, only whether the district court clearly erred. Here it 

did not. Although there were a variety of existing antipsychotics, they had debilitating negative side effects, which 

evidence indicates are reduced in Saphris. See, e.g., J.A. 

599, 603. While this may not be a particularly strong 

demonstration of long-felt need, the district court did not 

clearly err in finding it weighs in favor of non-obviousness. 

C. Unexpected Results

A showing of unexpected results can support a conclusion of non-obviousness. See United States v. Adams, 383 

U.S. 39, 51–52 (1966). In considering unexpected results, 

courts ask whether “the claimed invention exhibits some 

superior property or advantage that a person of ordinary 

skill in the relevant art would have found surprising or unexpected.” In re Soni, 54 F.3d 746, 750 (Fed. Cir. 1995). 

While we have permitted evidence from after the patent is 

granted to be considered in assessing whether there are 

unexpected results, Knoll Pharm. Co. v. Teva Pharm. USA, 

Inc., 367 F.3d 1381, 1385 (Fed. Cir. 2004), the results must 

be “unexpected by one of ordinary skill in the art at the 
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time of [the] application,” In re Geisler, 116 F.3d 1465, 1470 

(Fed. Cir. 1997).

Here, the district court found it was “surprising and 

unexpected” that the claimed “sublingual route of administration successfully resolved the serious cardiotoxic event 

reported in the ’476 patent.” J.A. 74. However, as the district court found, there was nothing in the prior art that 

indicated cardiotoxic problems existed with other routes of 

administration. J.A. 68. We explained in Soni that the 

reason why unexpected results support a conclusion of nonobviousness is simple: “that which would have been surprising to a person of ordinary skill in a particular art 

would not have been obvious.” 54 F.3d at 750. At the time 

of the claimed invention, a person of ordinary skill could 

not have been surprised that the sublingual route of administration did not result in cardiotoxic effects because 

the person of ordinary skill would not have been aware that 

other routes of administration do result in cardiotoxic effects. The district court, therefore, erred in its analysis of 

unexpected results.

D. Legal Conclusion

We review the ultimate question of obviousness de 

novo. Arctic Cat, 876 F.3d at 1365. Given the lack of an 

express finding that compliance concerns with patients 

who have trouble swallowing would not provide a motivation to combine, we vacate the district court’s judgment of 

non-obviousness and remand.

III. Written Description

Section 112 of the Patent Act requires the specification 

contain “a written description of the invention.” The written description requirement is met when “the disclosure of 

the application relied upon reasonably conveys to those 

skilled in the art that the inventor had possession of the 

claimed subject matter as of the filing date.” Ariad Pharm., 

Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010)
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(en banc). Written description is a question of fact, which 

we review for clear error. Pozen Inc. v. Par Pharm., Inc., 

696 F.3d 1151, 1166 (Fed. Cir. 2012).

Appellants argue the specification fails to describe 

asenapine free base in a rapidly disintegrating, sublingual,

or buccal solid composition. Both claims 1 and 4 require a 

“pharmaceutical composition” containing “trans-5-chloro2-methyl-2,3,3a,12b-tetrahydro-1H-dibenz[2,3:6,7]oxepino

[4,5-c]pyrrole or a pharmaceutically acceptable salt 

thereof.” The parties’ experts agree that “trans-5-chloro-2-

methyl-2,3,3a, 12b-tetrahydro-1H-dibenz[2,3:6,7]oxepino

[4,5-c]pyrrole or a pharmaceutically acceptable” is the free 

base of asenapine. 

The district court’s finding that the specification contains sufficient written description support for claims 1 and 

4 was not clearly erroneous. Appellants’ expert witness 

Dr. Gould acknowledged asenapine free base was known in 

the art. The specification repeatedly refers to pharmaceutical compositions containing asenapine free base. E.g., 

’476 patent at 1:33–36. While Appellants cite evidence that 

the properties of asenapine free base make it unsuitable for 

use in pharmaceutical development, the district court did 

not clearly err in finding that Appellants had not established invalidity for lack of written description by clear and 

convincing evidence.

IV. Infringement of Claim 4

The district court found Breckenridge and Alembic do 

not infringe claim 4 directly, indirectly, or under the doctrine of equivalents. [A82] Breckenridge and Alembic’s 

proposed generic products are indicated for the treatment 

of “manic episodes” associated with bipolar I disorder. 

Claim 4 is directed to “a method for treating tension, excitation, anxiety, and psychotic and schizophrenic disorders.” The court construed claim 4 to not cover the 

treatment of bipolar disorders. J.A. 57. We review the ultimate claim construction de novo and any subsidiary fact 
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findings about extrinsic evidence for clear error. CardSoft, 

807 F.3d at 1348. Because we hold that the district court 

erred in its claim construction, we vacate and remand as to 

infringement of claim 4.

The claim language and the specification indicate that 

“excitation” refers to a symptom rather than a “disorder.” 

The use of the conjunction “and” before “psychotic and 

schizophrenic disorders” indicates that “psychotic and 

schizophrenic disorders” is a distinct item on the list, and 

that unlike the terms “psychotic” and “schizophrenic,” the 

words “tension,” “excitation,” and “anxiety” are not describing “disorders.” This is consistent with how “excitation” is 

used elsewhere in the specification. ’476 patent at 5:55–58. 

Moreover, experts for both parties agree that there is no 

such thing as an “excitation disorder,” J.A. 218, 349, further indicating the claim covers treatment of the symptom 

“excitation” rather than treatment of an “excitation disorder.” Although excitation may be a symptom of bipolar I 

disorder, the district court nevertheless carved bipolar I 

disorder out of its construction because it concluded that 

the “language of the ’476 patent is directed to ‘diseases’ and 

‘disorders,’ not to symptoms of such.” J.A. 50. This misreads the plain language of the claims and specification.

Because the district court erred in treating “excitation” 

as being limited to “excitation disorders,” we vacate its 

finding of non-infringement. We construe “excitation” to 

refer to a symptom and remand for the district court to assess infringement in light of this construction.

CONCLUSION

We vacate the district court’s judgment that Claims 1 

and 4 are not invalid and remand for it to consider the limited question of whether compliance concerns with patients 

who have trouble swallowing would provide a motivation 

to combine and its impact on the obviousness analysis. We 

vacate its judgment of non-infringement of claims 4, 9, and 

10 as to Breckenridge and Alembic and remand for the 
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court to consider whether Breckenridge and Alembic infringe under our revised construction.

VACATED AND REMANDED

COSTS

No costs.