Court Opinion

ID: 4640116
Source: CourtListenerOpinion
Date Created: 2020-12-07 16:00:34.316251+00
Date Added: 2024-06-11T08:00:11.289500
License: Public Domain

Case: 19-2359   Document: 58     Page: 1    Filed: 12/07/2020

   United States Court of Appeals
       for the Federal Circuit
                 ______________________

    SIONYX LLC, PRESIDENT AND FELLOWS OF
              HARVARD COLLEGE,
             Plaintiffs-Cross-Appellants

                            v.

   HAMAMATSU PHOTONICS K.K., HAMAMATSU
              CORPORATION,
            Defendants-Appellants

                      DOES 1-10,
                       Defendant
                 ______________________

                  2019-2359, 2020-1217
                 ______________________

     Appeals from the United States District Court for the
 District of Massachusetts in No. 1:15-cv-13488-FDS, Judge
 F. Dennis Saylor IV.
                  ______________________

                Decided: December 7, 2020
                 ______________________

     WILLIAM D. BELANGER, Troutman Pepper Hamilton
 Sanders LLP, Boston, MA, argued for plaintiffs-cross-ap-
 pellants. Also represented by ANTHONY H. CATALDO,
 GWENDOLYN TAWRESEY.

    JOHN DAVID SIMMONS, Panitch Schwarze Belisario &
 Nadel LLP, Philadelphia, PA, argued for defendants-
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 2                   SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

 appellants. Also represented by KEITH AARON JONES,
 STEPHEN EMERSON MURRAY; KOICHIRO MINAMINO, Mina-
 mino Law Office, PLLC, Washington, DC.
                 ______________________

     Before LOURIE, REYNA, and WALLACH, Circuit Judges.
 LOURIE, Circuit Judge.
      Hamamatsu Photonics K.K. and Hamamatsu Corpora-
 tion (“Hamamatsu”) appeal from the judgment of the U.S.
 District Court for the District of Massachusetts after a jury
 verdict that (1) Hamamatsu breached its Non-Disclosure
 Agreement (“NDA”) with SiOnyx LLC (“SiOnyx”); (2) Ha-
 mamatsu willfully infringed U.S. Patent 8,080,467 (“the
 ’467 patent”); (3) SiOnyx is entitled to $796,469 in damages
 and $1,091,481 of pre-judgment interest for breach of the
 NDA; (4) SiOnyx is entitled to $580,640 in damages and
 $660,536 of pre-judgment interest for unjust enrichment;
 (5) SiOnyx is entitled to post-judgment interest at the stat-
 utory rate for its breach of contract and unjust enrichment
 claims; (6) Dr. James Carey is a co-inventor of U.S. Patents
 9,614,109; 9,293,499; 9,190,551; 8,994,135; 8,916,945;
 8,884,226; 8,742,528; 8,629,485; and 8,564,087 (collectively
 “the Disputed U.S. Patents”); (7) SiOnyx is entitled to sole
 ownership of the Disputed U.S. Patents; (8) SiOnyx is en-
 titled to an injunction prohibiting Hamamatsu from prac-
 ticing the Disputed U.S. Patents for breach of the NDA;
 and (9) SiOnyx is entitled to an injunction prohibiting Ha-
 mamatsu from practicing the ’467 patent for infringement.
 See SiOnyx, LLC v. Hamamatsu Photonics K.K., No. 1:15-
 cv-13488-FDS (D. Mass. Sept. 24, 2019), ECF No. 834.
      SiOnyx cross-appeals from the district court’s decisions
 (1) denying SiOnyx sole ownership of the Japanese patent
 applications from which the Disputed U.S. Patents claim
 priority and all other foreign patents claiming priority from
 the Japanese applications (collectively “the Disputed
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 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.                  3

 Foreign Patents”); and (2) denying SiOnyx’s motion for fees
 under 35 U.S.C. § 285.
     Because the district court erred in failing to grant Si-
 Onyx sole ownership of the Disputed Foreign Patents, we
 reverse the district court’s denial of SiOnyx’s motion to
 compel Hamamatsu to transfer ownership of those patents
 to SiOnyx. We decline to address the issue of willfulness
 and affirm the district court’s judgment in all other re-
 spects.
                         BACKGROUND
     This appeal arises from research conducted at Harvard
 University by Professor Eric Mazur and his then-student
 James Carey. In 1998, Mazur discovered a process for cre-
 ating “black silicon” by irradiating a silicon surface with
 ultra-short laser pulses. In addition to turning the silicon
 black, the process creates a textured surface, and the re-
 sulting black silicon has electronic properties different
 from traditional silicon. After discovering the process for
 making the material, Mazur worked with his students, in-
 cluding Carey, to study its properties and potential uses.
 Based on their work, Mazur and Carey filed U.S. Provi-
 sional Patent Application 60/293,590 on May 25, 2001,
 from which several patents eventually issued, including
 the ’467 patent.
                 I. THE PARTIES’ RELATIONSHIP
      Around 2005, Mazur and Carey founded SiOnyx to fur-
 ther develop and commercialize black silicon. Thereafter,
 SiOnyx sought to establish relationships with companies
 that may be interested in its technology. In November
 2006, SiOnyx met with Hamamatsu, which produces,
 among other things, silicon-based photodetector devices.
 SiOnyx gave a brief presentation on the discovery of black
 silicon and, on January 11, 2007, SiOnyx and Hamamatsu
 entered into the NDA to allow the parties to share confi-
 dential information relating to “evaluating applications
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 and joint[] development opportunities of pulsed laser pro-
 cess doped photonic devices.” J.A. 2881.
      The NDA includes several provisions that are relevant
 to this appeal. First, the NDA provides that a party receiv-
 ing confidential information (as defined in the agreement)
 shall maintain the information in strict confidence for
 seven years after the expiration of the agreement, after
 which the receiving party may use or disclose the confiden-
 tial information. J.A. 2881–82 ¶¶ 2, 8. Second, the agree-
 ment provides that a party receiving confidential
 information acknowledges that the disclosing party claims
 ownership of the information and all patent rights “in, or
 arising from” the information. J.A. 2882 ¶ 5. Finally, the
 agreement requires a party receiving confidential infor-
 mation to return all confidential information within 30
 days of the termination of the agreement. Id. ¶ 7.
     While the NDA was in effect, SiOnyx provided to Ha-
 mamatsu proposed architectures and a manufacturing pro-
 cess for a photodetector device, which were marked as
 confidential. Hamamatsu and SiOnyx worked together to
 produce experimental devices using SiOnyx’s process. Ha-
 mamatsu produced silicon wafers as it would to manufac-
 ture its traditional photodiodes, which were then sent to
 SiOnyx to perform SiOnyx’s laser-texturing process. The
 textured wafers were then returned to Hamamatsu to be
 cut, packaged, and tested. The sample devices produced
 favorable results, but Hamamatsu represented that it
 wished to develop its products alone “without further ref-
 erence to proprietary information of SiOnyx,” and the NDA
 expired on January 12, 2008. J.A. 3013. After expiration
 of the NDA, SiOnyx did not request that Hamamatsu re-
 turn any confidential information received from SiOnyx,
 and Hamamatsu did not do so.
     After the NDA was terminated, Hamamatsu continued
 to develop new photodetector devices. On February 1,
 2008, as part of its work developing a new commercial
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 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.                    5

 photodiode, Hamamatsu prepared an internal develop-
 ment report that referred to the prototype work done with
 SiOnyx. On February 9, 2009, Hamamatsu emailed Si-
 Onyx to inform SiOnyx that Hamamatsu intended to intro-
 duce a new photodiode at its Photon Fair exhibition that
 included a “black silicon surface fabricated by laser.”
 J.A. 3011. The email included a cross-sectional diagram of
 the structure of the photodiode and a performance curve.
 Hamamatsu stated that it did not believe that the new
 product infringed SiOnyx’s intellectual property or
 breached Hamamatsu’s confidentiality obligations. At the
 time, SiOnyx did not consider the product to be meaning-
 fully different from the devices the parties developed to-
 gether in 2007.
     On February 24, 2009, Hamamatsu filed the first of a
 series of Japanese patent applications relating to photode-
 tector devices. Hamamatsu subsequently filed patent ap-
 plications in several countries that claimed priority from
 these applications, including the U.S. applications that be-
 came the Disputed U.S. Patents. In 2010, Hamamatsu be-
 gan releasing the accused products, which include laser-
 textured photodiodes, avalanche photodiodes, and charge-
 coupled device (CCD) sensors. SiOnyx began selling its
 own photodetector products by 2013, and in 2014 one of Si-
 Onyx’s customers alerted SiOnyx to Hamamatsu’s patents.
 SiOnyx met with Hamamatsu to discuss ownership of the
 Disputed U.S. and Foreign Patents, but the parties did not
 reach an agreement.
                II. DISTRICT COURT PROCEEDINGS
      Having failed to reach an agreement with Hamamatsu
 regarding ownership of the patents, SiOnyx sued Hama-
 matsu in the District of Massachusetts. SiOnyx brought
 four claims: (1) breach of contract; (2) unjust enrichment;
 (3) infringement of the ’467 patent; and (4) change of inven-
 torship of the Disputed U.S. Patents. The case was tried to
 a jury on the issues of infringement, willfulness, invalidity,
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 inventorship, breach of contract, unjust enrichment, and
 damages. After a two-week trial, the jury returned a ver-
 dict in favor of SiOnyx. Specifically, the jury found that
 (1) Hamamatsu first breached the NDA on February 1,
 2008, when it referred to SiOnyx’s confidential information
 in an internal report, and awarding $796,469 in damages;
 (2) Hamamatsu was unjustly enriched beginning Janu-
 ary 10, 2010, and awarding $580,640 in damages; (3) Si-
 Onyx’s breach of contract and unjust enrichment claims
 were not barred by the statute of limitations; (4) Carey is a
 co-inventor of the Disputed U.S. Patents; and (5) the as-
 serted claims of the ’467 patent are valid and willfully in-
 fringed by Hamamatsu beginning December 20, 2011, but
 awarding $0 in damages.
      The parties filed numerous post-trial motions. Hama-
 matsu moved for judgment as a matter of law that (1) Si-
 Onyx’s breach of contract and unjust enrichment claims
 were barred by the statute of limitations; (2) that SiOnyx
 is not entitled to damages after the NDA’s confidentiality
 period ended on January 11, 2015; and (3) that Hamama-
 tsu did not willfully infringe the ’467 patent. The district
 court denied Hamamatsu’s motion. SiOnyx filed post-trial
 motions seeking (1) sole ownership of the Disputed U.S.
 Patents; (2) sole ownership of the Disputed Foreign Pa-
 tents; (3) an injunction for breach of the NDA prohibiting
 Hamamatsu from “making, using, offering for sale, selling,
 or importing the accused products and/or products practic-
 ing the [Disputed U.S. Patents]”; (4) an injunction for pa-
 tent infringement prohibiting Hamamatsu from “making,
 using, offering for sale, selling, or importing the accused
 products” practicing the ’467 patent; (5) pre- and post-judg-
 ment interest on damages awarded for breach of contract;
 (6) pre-judgment interest on damages awarded for unjust
 enrichment; and (7) fees under 35 U.S.C. § 285. The dis-
 trict court granted SiOnyx sole ownership of the Disputed
 U.S. Patents, injunctions on accused products practicing
 the Disputed U.S. Patents and the ’467 patent, pre- and
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 post-judgment interest on damages for breach of contract,
 and pre-judgment interest on damages for unjust enrich-
 ment. The court denied SiOnyx’s motions for ownership of
 the Disputed Foreign Patents and fees under § 285.
    Hamamatsu appealed, and SiOnyx cross-appealed. We
 have jurisdiction under 28 U.S.C. § 1295(a)(1).
                         DISCUSSION
      In reviewing issues tried to a jury, we review the dis-
 trict court’s denial of post-trial motions for judgment as a
 matter of law under the law of the regional circuit. See
 Finjan, Inc. v. Secure Computing Corp., 626 F.3d 1197,
 1202 (Fed. Cir. 2010) (citing Revolution Eyewear, Inc. v.
 Aspex Eyewear, Inc., 563 F.3d 1358, 1370 (Fed. Cir. 2009)).
 The First Circuit reviews denials of post-verdict motions
 for JMOL de novo, construing the facts in the light most
 favorable to the jury verdict and drawing any inferences in
 favor of the non-movant. Sánchez v. Foley, 972 F.3d 1, 10–
 11 (1st Cir. 2020) (citing Blomquist v. Horned Dorset Pri-
 mavera, Inc., 925 F.3d 541, 546 (1st Cir. 2019)). Judgment
 as a matter of law should be granted if “a reasonable jury
 would not have a legally sufficient evidentiary basis to find
 for the party on that issue.” FED. R. CIV. P. 50(a). “Our
 review, however, ‘is weighted toward preservation of the
 jury verdict,’ for ‘we must affirm unless the evidence was
 so strongly and overwhelmingly inconsistent with the ver-
 dicts that no reasonable jury could have returned them.’”
 Crowley v. L.L. Bean, Inc., 303 F.3d 387, 393 (1st Cir. 2002)
 (quoting Rodowicz v. Mass. Mut. Life Ins. Co., 279 F.3d 36,
 41–42 (1st Cir. 2002)). “‘Credibility determinations, the
 weighing of the evidence, and the drawing of legitimate in-
 ferences from the facts are jury functions, not those of a
 judge.’” Reeves v. Sanderson Plumbing Prods., Inc.,
 530 U.S. 133, 150–51 (2000) (quoting Anderson v. Liberty
 Lobby, Inc., 477 U.S. 242, 255 (1986)). As will be seen, this
 appeal largely, but not entirely, resolves itself on the fact
 that most of the determinations were made by a jury.
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                   I. HAMAMATSU’S APPEAL
     In this appeal, Hamamatsu challenges the district
 court’s judgment on the issues of the statute of limitations,
 pre-judgment interest, grant of an injunction for patent in-
 fringement, grant of an injunction for breach of contract,
 damages, ownership of the Disputed U.S. Patents, and
 willfulness. We address each issue in turn.
                  A. Statute of Limitations
     We first address Hamamatsu’s argument that Si-
 Onyx’s breach of contract and unjust enrichment claims
 are barred by Massachusetts’s six-year statute of limita-
 tions. The issue was presented to the jury and, although
 the jury found that Hamamatsu first breached the NDA on
 February 1, 2008—more than six years before SiOnyx filed
 its complaint—it nevertheless found that the claims are
 not barred by the statute of limitations. Hamamatsu
 moved for JMOL, which the district court denied. See Si-
 Onyx, LLC v. Hamamatsu Photonics K.K., No. 1:15-cv-
 13488-FDS (D. Mass. July 25, 2019), ECF No. 797.
     On appeal, Hamamatsu argues that the claims are
 barred because SiOnyx knew or should have known of Ha-
 mamatsu’s breach of the NDA more than six years prior to
 the filing of its complaint. According to Hamamatsu, at
 least two events that occurred more than six years prior to
 the filing of SiOnyx’s complaint should have alerted Si-
 Onyx to the likelihood of Hamamatsu’s breach, causing the
 claims to accrue and beginning the limitations period.
 First, Hamamatsu argues that SiOnyx knew of Hamama-
 tsu’s breach in February 2008, when Hamamatsu failed to
 return SiOnyx’s confidential information, as was required
 by the NDA. Second, Hamamatsu argues that SiOnyx
 should have known of Hamamatsu’s misuse of SiOnyx’s
 confidential information in February 2009, when Hama-
 matsu emailed SiOnyx a diagram of a photodiode that Si-
 Onyx perceived to be identical to the parties’ 2007 work.
 Both events were more than six years prior to the filing of
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 SiOnyx’s complaint and, according to Hamamatsu, should
 bar SiOnyx’s breach of contract and unjust enrichment
 claims.
     SiOnyx responds that Hamamatsu presented both de-
 fenses at trial, and the jury nonetheless determined that
 SiOnyx’s claims were not barred by the statute of limita-
 tions. According to SiOnyx, a reasonable jury could have
 determined that Hamamatsu’s failure to return SiOnyx’s
 confidential information was an immaterial breach that
 did not begin the limitations period, or that Hamamatsu
 concealed its later use of SiOnyx’s confidential information
 through its repeated assurances that its new products did
 not infringe SiOnyx’s intellectual property.
     We agree with SiOnyx. In Massachusetts, “any dis-
 puted issues relative to the statute of limitations ought to
 be decided by the jury.” Riley v. Presnell, 565 N.E.2d 780,
 787 (Mass. 1991). “In most instances, the question when a
 plaintiff knew or should have known of its cause of action
 is one of fact that will be decided by the trier of fact.” Tay-
 geta Corp. v. Varian Assocs., Inc., 736 N.E.2d 1053, 1063
 (Mass. 2002) (citing Riley, 565 N.E.2d at 787). Here, the
 jury was presented with the terms of the NDA, the circum-
 stances surrounding its expiration, and Hamamatsu’s fail-
 ure to return SiOnyx’s confidential information, and it
 found that the limitations period did not begin to run at
 that time. We agree with the district court that a reasona-
 ble juror could have determined that SiOnyx was not
 harmed by Hamamatsu’s failure to return the confidential
 information and that the breach was therefore immaterial
 and did not cause SiOnyx’s claims to accrue.
     Regarding the 2009 emails, the jury similarly was pre-
 sented with competing evidence, and concluded that the
 limitations period did not begin to run at that time. While
 Hamamatsu elicited testimony that SiOnyx was “con-
 cerned” about the similarities between Hamamatsu’s prod-
 ucts and the parties’ 2007 work, J.A. 624, the jury was also
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 presented with multiple statements by Hamamatsu to Si-
 Onyx that Hamamatsu’s products did not make use of Si-
 Onyx’s confidential information.          J.A. 3011, 3021.
 Weighing competing evidence is the quintessential func-
 tion of the jury and, confronted with this evidence, a rea-
 sonable jury could have determined that SiOnyx did not
 know, nor should it have known, of Hamamatsu’s breach
 at that time. As the district court noted, “[w]hether a plain-
 tiff knew or should have known of an injury so as to trigger
 the running of a statute of limitations is, with rare excep-
 tion, a jury issue,” SiOnyx, LLC v. Hamamatsu Photonics
 K.K., No. 1:15-cv-13488-FDS (D. Mass. July 25, 2019), ECF
 No. 797, slip op. at 2 (quoting Santiago Hodge v. Parke Da-
 vis & Co., 909 F.2d 628, 633 (1st Cir. 1990)), and we per-
 ceive no reason to upset the jury’s verdict here.
                  B. Pre-Judgment Interest
     Hamamatsu contends that the district court erred in
 awarding pre-judgment interest for SiOnyx’s breach of con-
 tract and unjust enrichment claims. Hamamatsu makes
 two principal arguments. First, it argues that no pre-judg-
 ment interest should be available for unjust enrichment
 based on disgorged profits. Second, Hamamatsu argues
 that the court erred in awarding interest for the breach of
 contract damages from the date of first breach because Si-
 Onyx suffered no financial harm until a later time. We con-
 sider Hamamatsu’s arguments in turn.
                     1. Unjust enrichment
      The parties’ dispute turns on whether the Massachu-
 setts statutory provision for pre-judgment interest for con-
 tract claims applies to disgorged profits for unjust
 enrichment. MASS. GEN. LAWS ch. 231, § 6C provides that
 “[i]n all actions based on contractual obligations . . . inter-
 est shall be added . . . to the amount of damages . . . from
 the date of the breach . . . .” Hamamatsu argues that, be-
 cause profit disgorgement is not designed to make the
 plaintiff whole, but rather to punish the defendant, it is not
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 “damages” within the meaning of the statute. For support,
 Hamamatsu relies on Governo Law Firm, LLC v. CMBG3
 Law, LLC, in which the Massachusetts Superior Court
 held that an “award to disgorge profits earned by the mis-
 use of trade secrets or confidential information is not ‘dam-
 ages’ within the meaning of the statutes that govern pre-
 judgment interest, and thus is not the sort of recovery as to
 which pre-judgment interest accrues as of right.” 2019 WL
 3801560, at *7 (Mass. Sup. Ct. July 29, 2019). SiOnyx re-
 sponds that § 6C applies to contract-based claims for un-
 just enrichment and therefore it is entitled to pre-judgment
 interest from the date of first breach. For its part, SiOnyx
 relies on Bushkin Associates, Inc. v. Raytheon Co., in which
 the First Circuit held that “quantum meruit is encom-
 passed by the pre-judgment interest statute.” 906 F.2d 11,
 15 (1st Cir. 1990).
     We agree with SiOnyx and the district court that dam-
 ages for unjust enrichment are subject to § 6C. Under Mas-
 sachusetts law, unjust enrichment is the “underlying basis
 for awarding quantum meruit damages in a quasi-contract
 case.” Salamon v. Terra, 477 N.E.2d 1029, 1031 (Mass.
 1985). Thus, the First Circuit’s holding in Bushkin that
 § 6C applies to quantum meruit appears to apply equally
 to SiOnyx’s contract-based unjust enrichment claim. To
 the extent that Governo appears to suggest otherwise, we
 note that in that case the court considered damages in the
 context of § 6B (the statute governing pre-judgment inter-
 est for tort claims), not § 6C. Accordingly, we agree that
 § 6C applies to the jury’s award of damages for unjust en-
 richment and that the district court correctly awarded pre-
 judgment interest from the date of first breach.
                     2. Breach of Contract
     We now turn to Hamamatsu’s second argument that
 awarding pre-judgment interest for SiOnyx’s breach of con-
 tract claim from the date of first breach determined by the
 jury is improper because SiOnyx did not suffer financial
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 harm at that time. Relying on Bank v. Thermo Elemental
 Inc., 888 N.E.2d 897 (Mass. 2008), and Sterilite Corp. v.
 Continental Casualty Co., 494 N.E.2d 1008 (Mass. 1986),
 Hamamatsu contends that, even under § 6C, pre-judgment
 interest should be awarded only from the time the plaintiff
 was deprived of funds, so as not to produce an undeserved
 windfall. Accordingly, Hamamatsu urges us to vacate the
 district court’s pre-judgment interest award and remand
 for a determination of the date when SiOnyx first suffered
 financial harm.
     We disagree with Hamamatsu. As an initial matter,
 Hamamatsu overreads the meaning of Thermo Elemental
 and Sterilite. In each of those cases, the plaintiff sought,
 and received, damages for payments that it was forced to
 make as a result of the defendant’s earlier breach of con-
 tract. That is, the damages were essentially reimburse-
 ment for expenditures of fixed amounts on known dates
 that the plaintiff would not have made but for the defend-
 ant’s breach. In those circumstances, even though the
 breach had occurred at an earlier date, disallowance of pre-
 judgment interest prior to the time that the plaintiff was
 improperly forced to lay out its own money for which it
 sought reimbursement is a reasonable interpretation of
 § 6C because the plaintiff had not lost access to those funds
 prior to those expenditures.
     But the circumstances here do not lend themselves to
 such a tidy accounting. At trial, the jury was presented
 with multiple damages theories, including a $1 million up-
 front license fee, J.A. 1700, a 7% royalty on sales of the ac-
 cused products, J.A. 1532, and over $2 million from a lost
 partnership with Nikon in 2015. J.A. 1557. The jury’s ul-
 timate award of $794,469 matches none of those theories,
 and the verdict forms shed no light on the jury’s perceived
 timing of the damages, other than the date on which the
 jury determined that Hamamatsu first breached the NDA.
 In light of the jury’s verdict, we discern no rational basis
 for assigning the jury’s damages award to specific dates
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 between 2008 and 2015 for the purpose of calculating pre-
 judgment interest, and therefore we see no reason to devi-
 ate from the general rule for pre-judgment interest on con-
 tract claims set out in § 6C.
      C. Injunction for Infringement of the ’467 Patent
     Hamamatsu argues that the district court erred in
 granting SiOnyx’s motion for a permanent injunction
 prohibiting Hamamatsu from “making, using, offering for
 sale, selling, or importing” the products held to infringe the
 ’467 patent. A party seeking a permanent injunction for
 patent infringement must demonstrate: “(1) that it has
 suffered an irreparable injury; (2) that remedies available
 at law, such as monetary damages, are inadequate to
 compensate for that injury; (3) that, considering the
 balance of hardships between the plaintiff and defendant,
 a remedy in equity is warranted; and (4) that the public
 interest would not be disserved by a permanent
 injunction.” eBay Inc. v. MercExchange, L.L.C., 547 U.S.
 388, 390–91 (2006). Hamamatsu argues primarily that
 SiOnyx failed to demonstrate irreparable harm and an
 inadequate remedy at law. Specifically, Hamamatsu
 argues that SiOnyx cannot show irreparable harm because
 SiOnyx’s products do not compete with the accused
 products. And because the parties do not directly compete,
 according to Hamamatsu, money damages could provide
 adequate compensation for Hamamatsu’s continued sales
 of the accused products. Hamamatsu has not argued the
 balance of harms and public interest factors, so we need not
 address them.
     SiOnyx responds that its products do in fact compete
 with the accused products. SiOnyx argues that it will
 suffer irreparable harm from Hamamatsu’s continued
 sales of the accused products because SiOnyx would be the
 only supplier of products practicing the technology
 disclosed in the ’467 patent but for Hamamatsu’s misuse of
 SiOnyx’s confidential information. Absent Hamamatsu’s
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 14                  SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

 reliance on SiOnyx’s confidential information, SiOnyx
 argues, Hamamatsu never could have entered the market,
 or at a minimum its entry would have been delayed, and
 therefore the court did not abuse its discretion in
 determining that damages at law would be impossible to
 quantify and inadequate.
      We agree with SiOnyx. We review the decision to grant
 a permanent injunction for an abuse of discretion. Robert
 Bosch LLC v. Pylon Mfg. Corp., 659 F.3d 1142, 1147 (Fed.
 Cir. 2011). “We may find an abuse of discretion on a show-
 ing that the court made a clear error of judgment in weigh-
 ing relevant factors or exercised its discretion based upon
 an error of law or clearly erroneous factual findings.” In-
 nogenetics, N.V. v. Abbott Lab’ys., 512 F.3d 1363, 1379
 (Fed. Cir. 2008) (internal quotation marks omitted). Based
 on the record before us, Hamamatsu has not demonstrated
 that the district court so erred. In granting the injunction,
 the district court found that SiOnyx’s laser-processed
 CMOS sensors are competitive products with Hamama-
 tsu’s accused CCD sensors. SiOnyx, LLC v. Hamamatsu
 Photonics K.K., No. 1:15-cv-13488-FDS, 2019 WL 3358599,
 at *3 (D. Mass. July 25, 2019). The court relied on the trial
 testimony of SiOnyx’s expert, Dr. Ezekiel Kruglick, that
 CMOS sensors or CCD sensors could be used for some ap-
 plications. J.A. 1438. Hamamatsu counters with the tes-
 timony of SiOnyx’s CEO, Steve Saylor, that Hamamatsu’s
 products “would not really get in the way of SiOnyx’s core
 business dramatically.” J.A. 876. But the existence of con-
 trary testimony alone does not make the district court’s
 finding clearly erroneous. See Anderson v. City of Bessemer
 City, 470 U.S. 564, 574 (1985) (“Where there are two per-
 missible views of the evidence, the fact-finder’s choice be-
 tween them cannot be clearly erroneous.” (citing United
 States v. Yellow Cab Co., 338 U.S. 338, 342 (1949))). Based
 on the record before us, we are not convinced that the dis-
 trict court clearly erred in finding that the accused prod-
 ucts are competitive with SiOnyx’s products, and
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 Hamamatsu has not otherwise persuasively refuted the
 demonstration of irreparable harm.
     Further, we conclude that the district court did not
 abuse its discretion in finding that money damages would
 be inadequate to compensate SiOnyx. The jury found that
 Hamamatsu breached its NDA with SiOnyx by using
 SiOnyx’s confidential information and that the accused
 products infringe the ’467 patent. Hamamatsu does not
 appeal those findings, and it is therefore evident that
 Hamamatsu’s development of the accused products and
 entry into the relevant markets were aided and accelerated
 by its improper use of SiOnyx’s confidential information.
 Because SiOnyx would have otherwise had those markets
 to itself, at least for some period of time, we agree with
 SiOnyx that it was not an abuse of discretion for the court
 to determine that it was difficult to quantify the harm to
 SiOnyx due to Hamamatsu’s premature entry in those
 markets. Accordingly, we affirm the district court’s grant
 of a permanent injunction for infringement of the ’467
 patent.
              D. Injunction for Breach of Contract
      The district court also granted a permanent injunction
 as a remedy for SiOnyx’s breach of contract claim, prohib-
 iting Hamamatsu from “making, using, offering for sale,
 selling, or importing the accused products and/or products
 practicing” the Disputed U.S. Patents. SiOnyx, LLC v. Ha-
 mamatsu Photonics K.K., No. 1:15-cv-13488-FDS, 2019 WL
 3358599, at *2 (D. Mass. July 25, 2019). We review non-
 patent issues under the law of the regional circuit. Versa-
 Top Support Sys., LLC v. Georgia Expo, Inc., 921 F.3d
 1364, 1368 (Fed. Cir. 2019). In Massachusetts, injunctive
 relief is appropriate where (1) the plaintiff would suffer ir-
 reparable harm absent injunctive relief, (2) there is inade-
 quate remedy at law, and (3) the harm to plaintiffs would
 outweigh the harm the defendant would suffer from the im-
 position of an injunction. See John T. Callahan & Sons,
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 16                  SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

 Inc. v. City of Malden, 713 N.E.2d 955, 960 (Mass. 1999)
 (citing Packaging Indus. Grp., Inc. v. Cheney, 405 N.E.2d
 106, 111–12 (Mass. 1980)). Trial judges have broad discre-
 tion to grant or deny injunctive relief, which is reviewed for
 abuse of discretion. Lightlab Imaging, Inc. v. Axsun Techs.,
 Inc., 13 N.E.3d 604, 614 (Mass. 2014) (citing Johnson v.
 Martignetti, 375 N.E.2d 290, 298 (Mass. 1978), and
 Curtiss–Wright Corp. v. Edel–Brown Tool & Die Co., 407
 N.E.2d 319, 326 (Mass. 1980)).
      Due to the similarity of the legal standard, the parties’
 arguments are substantially similar to those made with re-
 spect to the injunction for patent infringement, and we
 reach the same conclusion. Hamamatsu additionally ar-
 gues that the injunction does not prevent future harm to
 SiOnyx because the NDA’s confidentiality period has ex-
 pired, and the confidential information has been made pub-
 lic.   Thus, according to Hamamatsu, the injunction
 operates only to punish Hamamatsu for its past conduct.
 But Hamamatsu ignores the ongoing benefit it receives
 from having improperly used SiOnyx’s confidential infor-
 mation to develop its products. As we explained with re-
 spect to the injunction for infringement of the ’467 patent,
 it was not an abuse of discretion for the district court to
 determine that the harm to SiOnyx from Hamamatsu’s
 head start in developing its products and premature en-
 trance to the market was irreparable and not adequately
 remedied by money damages, and for the same reason, we
 affirm here.
        E. Damages After the Confidentiality Period
     Hamamatsu filed a post-trial motion for judgment as a
 matter of law that SiOnyx is not owed damages for the
 breach of contract and unjust enrichment claims after the
 confidentiality period of the NDA expired on January 11,
 2015. The district court denied the motion. See SiOnyx,
 LLC v. Hamamatsu Photonics K.K., No. 1:15-cv-13488-FDS
 (D. Mass. July 25, 2019), ECF No. 797. Hamamatsu argues
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 that the court erred in denying its motion because Hama-
 matsu’s use of that information was no longer in breach af-
 ter the confidentiality period ended, and SiOnyx therefore
 is entitled only to Hamamatsu’s profits through 2014. Si-
 Onyx responds that the jury reasonably could have inferred
 that Hamamatsu continued to benefit from its breach be-
 yond the expiration of the confidentiality period.
     We agree with SiOnyx. As we have noted above, and
 as the district court observed below, “[a]lthough [Hamama-
 tsu] may not have ‘disclosed’ confidential information after
 the nondisclosure agreement ended in January 2015, the
 jury’s verdict can be reasonably construed to incorporate a
 finding that [Hamamatsu] continued to reap the benefit of
 their earlier breach by selling products that it had designed
 using [SiOnyx’s] confidential information.” Id. slip op. at 3.
 We agree that such an inference is reasonable, and we de-
 cline to alter the jury’s damages award.
         F. Ownership of the Disputed U.S Patents
     In its complaint, SiOnyx requested correction of inven-
 torship of the Disputed U.S. Patents under 35 U.S.C. § 256
 to name Carey as inventor. The jury was charged with de-
 termining whether Carey was an inventor and, if so,
 whether he was the sole inventor or a co-inventor. The jury
 returned a verdict in favor of SiOnyx and found that Carey
 should be added as a co-inventor of the Disputed U.S. Pa-
 tents. In post-trial motions, SiOnyx asked the district
 court to grant sole ownership of all disputed patents to Si-
 Onyx as a remedy for Hamamatsu’s breach of contract.
 J.A. 2239. SiOnyx’s request was based on Paragraph 5 of
 the NDA, which provides that “[t]he Receiving Party
 acknowledges that the Disclosing Party . . . claims owner-
 ship of the Confidential Information disclosed by the Dis-
 closing Party and all patent, copyright, trademark, trade
 secret, and other intellectual property rights in, or arising
 from, such Confidential Information.” J.A. 2882.
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     The court granted SiOnyx’s motion with respect to the
 Disputed U.S. Patents and denied the motion with respect
 to the Disputed Foreign Patents. See SiOnyx, LLC v. Ha-
 mamatsu Photonics K.K., No. 1:15-cv-13488-FDS, 2019 WL
 3358599 (D. Mass. July 25, 2019); SiOnyx, LLC v. Hama-
 matsu Photonics K.K., No. 1:15-cv-13488-FDS (D. Mass.
 Sept. 24, 2019), ECF No. 831. The court reasoned that the
 jury’s verdict that Hamamatsu breached the NDA by using
 SiOnyx’s confidential information and that Carey should
 be named a co-inventor of the Disputed U.S. Patents nec-
 essarily implies that those patents arose, at least in part,
 from SiOnyx’s confidential information. SiOnyx, 2019 WL
 3358599, at *1. Thus, the court concluded that SiOnyx
 should be granted ownership of the patents under Para-
 graph 5 of the NDA. Id. at *2. With respect to the Disputed
 Foreign Patents, the court did not question whether the
 same rationale applied, but nonetheless declined to grant
 ownership to SiOnyx because the court questioned its au-
 thority to do so. We address the district court’s decision
 with respect to the Disputed U.S. Patents here and the Dis-
 puted Foreign Patents in SiOnyx’s cross-appeal, below.
      On appeal, Hamamatsu argues that the district court
 erred in granting SiOnyx sole ownership of the Disputed
 U.S. Patents because the jury’s finding of co-inventorship
 necessarily implies that the jury found that Hamamatsu
 also contributed to the patents. According to Hamamatsu,
 it is therefore equally entitled to ownership under Para-
 graph 5 of the NDA because the patents also “arose from”
 its information. SiOnyx responds that the court did not
 abuse its discretion because the jury’s verdict establishes
 that the patents are based on its confidential information,
 requiring transfer of ownership under Paragraph 5 of the
 NDA.
     The district court’s decision transferring ownership of
 the patents according to the terms of the NDA is an equi-
 table remedy which is reviewed for abuse of discretion un-
 der Massachusetts law. Cavadi v. DeYeso, 941 N.E.2d 23,
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 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.                    19

 31 (Mass. 2011) (quoting Demoulas v. Demoulas, 703
 N.E.2d 1149, 1174 (Mass. 1998)). We agree with SiOnyx
 that the district court did not abuse its discretion in grant-
 ing SiOnyx sole ownership of the Disputed U.S. Patents.
 “It is elementary that inventorship and ownership are sep-
 arate issues,” Beech Aircraft Corp. v. EDO Corp., 990 F.2d
 1237, 1248 (Fed. Cir. 1993), and while conception is the
 touchstone of inventorship, ownership operates based on
 contract or law—in this case, the NDA. Corporations are
 not inventors, but they derive ownership rights through
 contracts, usually with employees, or provisions of law.
 Thus, while Hamamatsu employees may be co-inventors,
 and their rights transferred to their employer, Hamama-
 tsu, Hamamatsu is the contracting party in the NDA, and
 the NDA provides that ownership of patents arising from
 confidential information exchanged under the agreement
 is claimed by the disclosing party. But Hamamatsu has
 not established that any of the patents arose from confiden-
 tial information disclosed under the agreement and there-
 fore has failed to show that it is entitled to joint ownership.
      The primary shortcoming in Hamamatsu’s argument is
 its conflation of the contribution of any information to the
 patents with the contribution of confidential information
 within the meaning of the NDA. To the extent that the
 jury’s finding implies that Hamamatsu contributed its own
 information to the patents, it does not necessarily follow
 that Hamamatsu contributed confidential information to
 the patents within the meaning of the NDA, other than
 that which it appropriated from SiOnyx. In its briefing,
 Hamamatsu does not direct us to any evidence presented
 to the jury or to the district court even suggesting that the
 patents arose in part from its confidential information such
 that Paragraph 5 also operates to assign co-ownership to
 Hamamatsu, and we cannot otherwise identify any. Ab-
 sent evidence that Hamamatsu contributed confidential in-
 formation to the patents under the NDA, it is not entitled
 to co-ownership of the patents under the agreement.
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 20                 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

     Aside from the absence of evidence that Hamamatsu
 contributed confidential information to the patents, the im-
 plication that Hamamatsu made other contributions to the
 patents does not warrant a different result. To the extent
 that the jury’s finding that Carey is a co-inventor rather
 than the sole inventor implies that Hamamatsu personnel
 contributed to the claimed inventions, the modification of
 claims founded upon SiOnyx’s confidential information
 “does not negate the imposition of an equitable remedy,”
 Richardson v. Suzuki Motor Co., Ltd., 868 F.2d 1226, 1249
 (Fed. Cir. 1989), and does not demonstrate that the district
 court abused its discretion to provide equitable relief. Ac-
 cordingly, we affirm the district court’s decision granting
 sole ownership of the Disputed U.S. Patents to SiOnyx.
                       G. Willfulness
     Finally, Hamamatsu appeals the willfulness judgment.
 The jury returned a verdict finding that Hamamatsu’s in-
 fringement of the ’467 patent was willful. Despite its find-
 ing of willful infringement, the jury awarded SiOnyx $0 in
 damages for Hamamatsu’s infringement. SiOnyx filed a
 post-trial motion for enhanced damages under 35 U.S.C.
 § 284, requesting that the district court assess $490,889 in
 damages for patent infringement and treble those damages
 based on the jury’s finding of willfulness. SiOnyx, LLC v.
 Hamamatsu Photonics K.K., No. 1:15-cv-13488-FDS, 2019
 WL 3358691, at *1 (D. Mass. July 25, 2019). The court de-
 clined to assess damages for patent infringement, conclud-
 ing that “it is certainly reasonable to interpret the jury’s
 verdict as a rational attempt to award damages for both
 breach of contract and patent infringement while avoiding
 an award of duplicative damages.” Id. at *2. Because the
 court could not ascertain the amount of damages the jury
 intended to award for patent infringement, the court held
 that “it is impossible to treble that amount” and denied Si-
 Onyx’s motion for enhanced damages. Id. Nonetheless,
 Hamamatsu moved for judgment as a matter of law on will-
 fulness, which the district court denied.
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 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.                  21

      On appeal, Hamamatsu maintains that its infringe-
 ment was not willful, challenging the adequacy of the evi-
 dence presented at trial to support the jury’s finding.
 However, given that the district court awarded no en-
 hanced damages based on willfulness, it is not apparent
 what effect the jury’s finding of willfulness had on the dis-
 trict court’s judgment, and it is likewise not apparent what
 the effect a reversal by this court would be. We cannot re-
 duce the enhanced damages awarded to SiOnyx for Hama-
 matsu’s allegedly willful infringement because no such
 damages exist. Because there is no “tangible, demonstra-
 ble consequence” to the jury’s finding of willfulness, our
 consideration of the issue would be tantamount to an advi-
 sory opinion, which we lack the authority to provide. Sam-
 sung Elec. Co., Ltd. v. Rambus, Inc., 523 F.3d 1374, 1380
 (Fed. Cir. 2008) (quoting Chathas v. Local 134 IBEW, 233
 F.3d 508, 512 (7th Cir. 2000)). Accordingly, we decline to
 address the willfulness issue.
                  II. SIONYX’S CROSS-APPEAL
     SiOnyx raises two issues in its cross-appeal. First, it
 argues that the district court erred in denying its request
 to grant SiOnyx sole ownership of the Disputed Foreign Pa-
 tents. Second, it argues that the district court erred in
 denying its motion for attorney fees under 35 U.S.C. § 285.
       A. Ownership of the Disputed Foreign Patents
     Although the district court granted sole ownership of
 the Disputed U.S. Patents to SiOnyx, it declined to grant
 to SiOnyx ownership of the Disputed Foreign Patents—
 that is, Hamamatsu’s Japanese patents and any non-U.S.
 patents claiming priority therefrom. SiOnyx, LLC v. Ha-
 mamatsu Photonics K.K., No. 1:15-cv-13488-FDS (D. Mass.
 Sept. 24, 2019), ECF No. 831. The court appears to have
 declined to do so for two principal reasons: first, uncer-
 tainty regarding the court’s jurisdiction to grant ownership
 of foreign patents; and second, failure by SiOnyx ade-
 quately to identify the foreign patents for which it was
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 22                  SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

 requesting ownership. SiOnyx contends that the district
 court erred because the same evidence that establishes its
 right to sole ownership of the Disputed U.S. Patents estab-
 lishes its right to sole ownership of the Disputed Foreign
 Patents, and the court had authority to compel the transfer
 of ownership of the foreign patents because the court had
 jurisdiction over Hamamatsu. Hamamatsu’s argument to
 the contrary is substantially similar to its argument with
 respect to the Disputed U.S. Patents—that is, Hamamatsu
 also contributed to the Japanese applications and foreign
 counterparts, and therefore SiOnyx is entitled at most to
 joint ownership.
      We agree with SiOnyx that the evidence that estab-
 lished SiOnyx’s right to sole ownership of the Disputed
 U.S. Patents also applies to the Disputed Foreign Patents.
 And because the district court erroneously perceived that
 it lacked authority to compel the transfer of ownership, we
 conclude that it was an abuse of discretion to distinguish
 between the two groups of patents. As we discussed above
 with respect to the Disputed U.S. Patents, we agree that
 the jury’s findings compel the conclusion that those patents
 arose from SiOnyx’s confidential information and that Ha-
 mamatsu has not shown that it contributed confidential in-
 formation entitling it to joint ownership. And because the
 Disputed U.S. Patents claim priority from Hamamatsu’s
 Japanese patent applications, the Japanese applications
 must be for the same inventions as the Disputed U.S. Pa-
 tents. See 35 U.S.C. § 119(a). Thus, Hamamatsu’s Japa-
 nese patent applications and any applications claiming
 priority from the Japanese applications in other countries
 must also have arisen from SiOnyx’s confidential infor-
 mation. Accordingly, we conclude that SiOnyx is entitled
 to sole ownership of the Japanese applications and any for-
 eign applications claiming priority therefrom.
     Turning to the district court’s jurisdiction to grant own-
 ership of foreign patents, it is well established that courts
 have authority to compel parties properly before them to
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 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.                   23

 transfer ownership of foreign patents, just as they would
 any other equitable remedy. See Richardson, 868 F.2d at
 1249. This is because an order compelling a party to assign
 ownership of a foreign patent is an exercise of the court’s
 authority over the party, not the foreign patent office in
 which the assignment is made. Here, there is no argument
 that the district court lacked jurisdiction over Hamamatsu,
 and therefore the court had authority to compel assign-
 ment of foreign patents. And our judgment does not in any
 way deal with validity of foreign patents, which is a matter
 for foreign courts and patent offices. Because we perceive
 no rational basis for disparate treatment of the Disputed
 U.S. Patents and the Disputed Foreign Patents, we con-
 clude that the district court abused its discretion in declin-
 ing to grant to SiOnyx sole ownership of Hamamatsu’s
 Japanese applications and any foreign applications claim-
 ing priority therefrom.
                      B. Section 285 Fees
      Finally, SiOnyx argues that the district court abused
 its discretion in denying SiOnyx’s motion to declare this
 case exceptional under 35 U.S.C. § 285. See SiOnyx, LLC
 v. Hamamatsu Photonics K.K., No. 1:15-cv-13488-FDS
 (D. Mass. July 25, 2019), ECF No. 798. Under § 285, a
 “court in exceptional cases may award reasonable attorney
 fees to the prevailing party.” An exceptional case under
 § 285 is “one that stands out from others with respect to
 the substantive strength of a party’s litigating position
 (considering both the governing law and the facts of the
 case) or the unreasonable manner in which the case was
 litigated.” Octane Fitness, LLC v. ICON Health & Fitness,
 Inc., 572 U.S. 545, 554 (2014). SiOnyx argues that this case
 is exceptional in both respects. First, it argues that the
 strength of Hamamatsu’s litigating position was exception-
 ally weak due to its overt copying of SiOnyx’s patented
 technology, as evidenced by the jury’s finding of willful in-
 fringement. Second, SiOnyx argues that Hamamatsu’s lit-
 igation conduct was unreasonable because it sought to
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 24                  SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

 increase the cost and duration of litigation to strain Si-
 Onyx’s resources. SiOnyx urges that the district court ap-
 plied the wrong legal standard by requiring evidence that
 Hamamatsu “deliberately attempted” to increase the cost
 and complexity of the case for an improper purpose.
     Hamamatsu responds that the district court did not
 abuse its discretion in denying SiOnyx’s motion. Hamama-
 tsu argues that the jury’s finding of willful infringement is
 not determinative of whether a case is exceptional under
 § 285, and that its litigation conduct was consistent with
 an aggressive defense but was not otherwise uncommon or
 exceptional.
      We agree with Hamamatsu. We review the grant or
 denial of attorney fees under § 285 for an abuse of discre-
 tion. Highmark Inc. v. Allcare Health Mgmt. Sys., Inc., 572
 U.S. 559, 563–64 (2014); Bayer CropScience AG v. Dow
 AgroSciences LLC, 851 F.3d 1302, 1306 (Fed. Cir. 2017)
 (citing Mentor Graphics Corp. v. Quickturn Design Sys.,
 Inc., 150 F.3d 1374, 1377 (Fed. Cir. 1998)). To satisfy that
 standard, an appellant must demonstrate that the district
 court made “a clear error of judgment in weighing relevant
 factors or in basing its decision on an error of law or on
 clearly erroneous factual findings.” Bayer, 851 F.3d at
 1306 (quoting Mentor Graphics, 150 F.3d at 1377). While
 willfulness is “among the reasons that a court may find a
 case to be exceptional,” Therasense, Inc. v. Becton, Dickin-
 son & Co., 745 F.3d 513, 516 (Fed. Cir. 2014), “an attorney
 fee award is not mandatory when willful infringement has
 been found,” WhitServe, LLC v. Computer Packages, Inc.,
 694 F.3d 10, 37 (Fed. Cir. 2012) (citing Spectralytics, Inc. v.
 Cordis Corp., 649 F.3d 1336, 1349 (Fed. Cir. 2011)). Here,
 despite the jury’s finding of willful infringement, the dis-
 trict court concluded that Hamamatsu’s noninfringement
 and invalidity defenses were not so weak as to be excep-
 tional, in particular noting that SiOnyx failed even to move
 for summary judgment on those issues. While the district
 court may have been permitted to award fees under § 285
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 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.                    25

 based on the jury’s finding of willfulness, it was not re-
 quired to do so, and SiOnyx has not otherwise demon-
 strated that Hamamatsu’s infringement defenses were so
 weak as to be exceptional.
      With regard to Hamamatsu’s litigation conduct, we re-
 ject SiOnyx’s argument that the district court applied the
 wrong legal standard. While the court observed that Si-
 Onyx “provided no evidence that counsel deliberately at-
 tempted to increase the cost and complexity of this case for
 any improper purpose,” it is apparent that the court
 treated this as a factor in its inquiry, not as a legal stand-
 ard. SiOnyx otherwise relies on several aspects of the liti-
 gation as evidence that Hamamatsu intentionally extended
 the litigation to increase SiOnyx’s costs, including Hama-
 matsu’s refusal to settle, refusal to waive service of process,
 providing incomplete information during discovery, and ex-
 cessive post-trial motions. But while Hamamatsu’s con-
 duct may have had the effect of extending the litigation and
 commensurately increasing cost, we cannot say that the
 district court abused its discretion in not finding that delay
 alone was Hamamatsu’s purpose. Hamamatsu was not ob-
 ligated to settle or to waive service. And having dealt di-
 rectly with the parties’ discovery disputes and post-trial
 motions, the district court was well-situated to determine
 whether Hamamatsu’s conduct was unreasonable. Ulti-
 mately, abuse of discretion is a deferential standard, and
 while the district court may have been within its right to
 grant SiOnyx’s motion for fees under these circumstances,
 we cannot say that it abused its discretion in denying fees.
                         CONCLUSION
     We have considered the parties’ remaining arguments
 but find them unpersuasive. For the foregoing reasons, we
 reverse the district court’s decision denying SiOnyx sole
 ownership of the Disputed Foreign Patents. We decline to
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 26                 SIONYX LLC   v. HAMAMATSU PHOTONICS K.K.

 address the issue of willfulness and affirm the district
 court’s judgment in all other respects.
      AFFIRMED-IN-PART, REVERSED-IN-PART
                          COSTS
      Costs to SiOnyx.