By Kevin E. Noonan —

The Washington Legal Foundation (WLF), a self-styled "non-profit public interest law and policy center that regularly appears before federal and state courts to promote economic liberty, free enterprise, and a limited and accountable government," filed an amicus curiae brief on September 8th, urging the Federal Circuit to rehear en banc Eli Lilly's appeal of the Court's affirmance of an invalidity finding of U.S. Patent 5,464,826.  The Federal Circuit affirmed a District Court determination that the claims of the '826 patent were invalid over the claims of Lilly's U.S. Patent No. 4,808,614 under the judicially-created doctrine of obviousness-type double patenting.  The '826 patent claimed methods for using gemcitabine (sold by Lilly under the name GEMZAR®) for treating cancer, and the earlier '614 patent disclosed but did not claim this use.  The lawsuit between the parties arose after Sun filed an ANDA for generic gemcitabine, and Sun Pharmaceuticals filed a declaratory judgment action that the '614 and '826 patents (both of which were listed in the FDA's Orange Book) were invalid.

The Federal Circuit in its panel decision based affirmance on its earlier decisions in Geneva Pharm., Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373 (Fed. Cir. 2003), and Pfizer, Inc. v. Teva Pharm. USA, Inc., 518 F.3d 1353 (Fed. Cir. 2008), that the only type of applications that qualify for the "safe harbor" provisions of 35 U.S.C. § 121 were divisional applications, i.e., applications filed in response to a Patent Office-promulgated restriction requirement.  Restriction is proper if the Office determines that an application claims more than one patentably-distinct invention, and the safe harbor protects applicants from inconsistent determinations from the Office that the claims are patentably-distinct for restriction purposes but fall within the scope of the obviousness-type double patenting doctrine.

Here, the '614 patent was a continuation-in-part of an earlier-filed application whose description of methods of using gemcitabine were limited to the compound's antiviral activities.  The '826 patent, which arose from an application filed on the same day as the '614 patent, claimed the use of gemcitabine for treating cancer.  The District Court's obviouness-type double patenting determination as well as the Federal Circuit's affirmance were ultimately grounded in the policy considerations enunciated in Pfizer and Geneva Pharm.:

It would shock one's sense of justice if an inventor could receive a patent upon a composition of matter, setting out at length in the specification the useful purposes of such composition, . . . and then prevent the public from making any beneficial use of such product by securing patent upon each of the uses to which it may be adapted.

Pfizer, 518 F.3d at 1368 n.8; Geneva Pharm., 349 F.3d at 1386.

The WLF objects to this "expansion" of the obviousness-type double patenting doctrine in its amicus brief.  The group argues that the Court's decisions threaten to lower the incentive to innovate by limiting a patentee's ability to protect improvements in their inventions.  Citing Miller v. Eagle Mfg. Co., 151 U.S. 186, 198 (1894), the brief argues that it is settled law that "an inventor may obtain 'a separate patent' for a 'new improvement on his own invention.'"  Id. at 199.  Indeed, the brief argues that "[h]ad anyone other than Eli Lilly discovered this method of treating cancer with gemcitabine, quite clearly they would have been entitled to a patent," citing Lilly's brief in support of its petition for rehearing en banc.  WLF's brief also argues that "Miller specifically precludes the possibility that a patent that merely describes a separately patentable invention renders another patent claiming that invention invalid under the doctrine of double patenting." 151 U.S. at 198, an interpretation directly contrary to the panel decision here.

The brief recognizes that the panel believes that its decision was consistent with the Geneva Pharm. decision, but distinguished this case by characterizing the panel decision here as "extending" the holding in Geneva Pharm — specifically, asserting that in that case, a compound and its "only" use were not patentably distinct, whereas gemcitabine had "two separate methods of use," making Takeda v. Doll, 561 F.3d 1372 (Fed. Cir. 2009), the appropriate prior precedent.  In the Takeda case, the Court held that a later-claimed method of making a claimed pharmaceutical was patentably distinct provided that "a second method of making the same pharmaceutical was discovered before the filing of the application that led to the second patent."  Id. at 1377.  Since the application leading to the '826 patent was filed on the same day as the invalidating '614 patent, "the new method necessarily was discovered prior to the filing of either patent" (emphasis in original).  Thus, the brief concludes, "discovery of the second method of using the compound should have rendered both the new method and the older method patentably distinct from the compound."

The brief also notes that the Court's decision here is contrary to Patent Office restriction practice, which "categorically barred an applicant from presenting claims to a compound and two distinct methods of using that compound.  37 C.F.R. §§ 1.141(a)-(b) (1984)."  Had Lilly presented claims to both methods of use in the same patent, the brief argues that the application would have been subject to a restriction requirement, which would have forced these claims to be pursued in two separate patents.  This part of the brief implies strongly that it is equally "a shock to a sense of justice" to have substantive rights so influenced by procedural details of whether the claims are presented in the same or separate applications (an argument that depends on the unique facts here that the '614 and '826 application were effectively filed on the same day), in view of these established rules of practice.  The brief argues that the en banc Court should solicit the PTO's views on this question.