United States: Written Description In Amgen V. Sanofi: Is The Federal Circuit Possessed? Will SCOTUS Grant Certiorari?

Last Updated: January 8 2019
Article by John A. Bauer and John Buchanan

In the continuing Amgen v. Sanofi saga, Amgen has asked SCOTUS to take up the issue of written description, which is currently established by showing "whether the disclosure...reasonably conveys...that the inventor had possession of the claimed subject matter as of the filing date." Ariad Pharms., Inc. v. Eli Lilly & Co., 598 F.3d 1336, 1351 (Fed. Cir. 2010)(en banc)(emphasis added).

Amgen's petition is borne out of a patent dispute between Amgen and Sanofi over competing FDA-approved cholesterol-lowering antibody drugs. A jury in the district court of Delaware found Amgen's patents not invalid. Amgen Inc. v. Sanofi, 227 F. Supp. 3d 333 (D. Del. 2017). Significantly, the judge precluded Sanofi from introducing any post-priority-date evidence to show the patents did not comply with the written description or enablement requirements. The judge also instructed the jury, over Sanofi's objections, that written description of an antibody can be satisfied "by the disclosure of a newly-characterized antigen...if you find that the level of skill and knowledge in the art of antibodies at the time of filing was such that production of antibodies against such an antigen was conventional or routine." Amgen Inc. v. Sanofi, 872 F.3d 1367, 1372 (Fed. Cir. 2017)(also known as the "newly characterized antigen" test).

On appeal, the Federal Circuit affirmed in part and reversed and remanded in part. 872 F.3d at 1381. It held the district court erred when it categorically excluded Sanofi's post-priority-date evidence in determining whether the claims were described or enabled. It also held the district court erred when it allowed the "newly characterized antigen" test to be used as a jury instruction for complying with the written description requirement. Id. at 1378–79. The Federal Circuit further instructed that the district court may instruct the jury that the written description requirement can be satisfied if the specification discloses either a representative number of species falling within the scope of the genus or discloses structural features common to the members of the genus so that one of skill in the art can visualize or recognize the members of the genus. Id. at 1376. The Federal Circuit then vacated the injunction, and remanded for a new trial on written description and enablement. Id. at 1381–82.

In response to the adverse Federal Circuit decision, Amgen filed a petition for certiorari, presenting the question: whether the standard for compliance with the written description requirement of 35 U.S.C. § 112(a) should be based on court-created standards, e.g., "possession," or the express language of § 112(a), i.e., the "written description of the invention" must be "in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains . . . to make and use the same . . . ".

Amgen's petition asserts the latter, arguing that the express language of 35 U.S.C. § 112(a) mandates the answer. 35 U.S.C. § 112(a) states, in relevant part:

"The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains . . . to make and use the same . . . ".

Amgen argues that the Federal Circuit has misconstrued § 112(a) by interpreting the statutory language "in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains . . . to make and use" to not govern the written description of the invention, but rather, to govern a separate "enablement" requirement ("the manner and process of making and using."). Further, by misinterpreting the statutory language "in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains . . . to make and use" to not govern the written description of the invention, the Federal Circuit has erroneously fabricated a separate written description requirement of showing "possession" of the invention: "[A] patentee must convey in its disclosure that it 'had possession of the claimed subject matter as of the filing date.'" Ariad at 1351.

According to Amgen, the statutory text of 35 U.S.C. § 112(a) precludes separate "written description" and "enablement" requirements subject to different standards. In support thereof, Amgen's petition provides a detailed grammatical argument analyzing the statutory language of § 112(a), concluding that "a written description" must enable a skilled artisan to make and use the invention. There is no separate requirement for the "written description" to show "possession" of the invention.

Further, according to Amgen, the Federal Circuit's written description "possession" standard has led to more confusion than clarity. The Federal Circuit has developed an array of sub tests to show "possession" (e.g., the "representative-species" test, the "structure-function" test, and "common-structural-features" test). These sub-tests have left innovators with no way of predicting what disclosures will be sufficient. Moreover, and most importantly, these sub-tests cannot be reconciled with the statutory text of § 112(a).

Amgen's position has been supported by an amicus curiae brief filed by Bristol-Myers Squibb, Morphosys, Bavarian Nordic, and UCB Biopharma. Notably, the amicus asserts that the Federal Circuit, just as in Bilski and KSR, has created a narrow and inflexible rule where, instead, a contextual inquiry is needed. "[M]ore than once," this Court has "cautioned" the Federal Circuit "that courts should not read into the patent laws limitations and conditions which the legislature has not expressed."

Sanofi filed its brief in opposition on November 19, 2018, primarily asserting that it was improper for Amgen to present its "possession" question because it was not raised or considered below, would not be dispositive, and may be rendered moot by the upcoming district court jury trial scheduled for February 2019. Amgen filed its reply on December 4, 2018, countering many of Sanofi's arguments. The case has now been distributed for conference of January 4, 2019.

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