In Yeda Research and Development Co., Ltd. v. Abbott GMBH & Co. KG, Slip Op. 2015-1662 (Fed. Cir. 2016), the Federal Circuit held that a claim to an isolated protein described by its partial amino acid sequence satisfies 35 U.S.C. § 112 (written description) when the partial sequence is combined with other identifying characteristics of the protein.

A Purified and Isolated TNFα Binding Protein

Yeda Research and Development Co., Ltd. (Yeda) appealed two decisions by the U.S. District Court for the District of Columbia, that were in turn appeals of two decisions by the USPTO Board of Patent Appeals and Interferences, regarding Yeda’s allegation that Abbott Gmbh & Co. KG’s (Abbott) U.S. Patent No. 5,344,915 entitled “Proteins and Preparations Thereof” (‘915 Patent) is invalid as anticipated by an intervening prior art reference. Yeda and Abbott did not dispute that the reference anticipated the claims if the claims were entitled to its earliest priority.

The ‘915 Patent, was filed on September 26, 1991 and claims priority to two German applications, P39 15 072 (the ‘072 application), filed on May 9, 1989 and P39 22 089 (the ‘089 application), filed on July 5, 1989.

The ‘915 Patent issued with three claims. Claim 1 was determined to be representative:

  1. A purified and isolated TNFα-binding protein which has a molecular weight of about 42,000 daltons and has at the N terminus the amino acid sequence

Xaa Thr Pro Tyr Ala Pro Glu Pro Gly Set Thr Cys Arg Leu Arg Glu

where Xaa is hydrogen, a phenylalanine residue (Phe) or the amino acid sequences Ala Phe, Val Ala Phe, Gln Val Ala Phe, Ala Gln Val Ala Phe, Pro Ala Gln Val Ala Phe or Leu Pro Ala Gln Val Ala Phe.

Inherent Disclosure Can Provide Adequate Written Description

Prior to addressing the substance of the challenge, the court first reviewed the legal standard for written description. Citing its en banc decision Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., 598 F.3d 1336 (Fed. Cir. 2010), the court held that for the claims of an application to benefit from a priority application’s filing date, the claimed invention must be “disclosed in a way that clearly allows a person of ordinary skill to recognize that the inventor invented what is claimed and possessed the claimed subject matter at the filing date.” Id. at 1351.

Yeda argued that to gain the benefit of the earlier application’s filing date, Abbott must show that at the time of filing the priority application (here, the ‘072 application), a person of ordinary skill in the art would have understood that the claimed protein contained more than the partial sequence disclosed in the ‘072 application, i.e., the additional amino acids described in the ‘915 Patent specification. Abbott disagreed and argued that the ‘072 application need only describe and enable the claimed protein, and that a protein can be adequately described when a partial amino acid sequence is disclosed along with other biological characteristics.

The court agreed with Abbott, explaining that under the doctrine of inherent disclosure, “when a specification describes an invention that has certain undisclosed yet inherent properties, that specification serves as adequate written description to support a subsequent patent application that explicitly recites the invention’s inherent properties.” Slip Op. at 6. The court determined that the doctrine applied because it was “undisputed that the invention described in an earlier application was the exact invention claimed by the later patent.” Slip Op. at 7.

Finally, the court rejected Yeda’s argument that Abbott cannot rely on inherent disclosure on the ground that the inherent limitation cannot be material to the patentability of the invention. Yeda argued that the amino acids absent from the priority application are material because Abbott relied upon their absence to distinguish prior art during examination. During examination, the claims were rejected on prior art that disclosed a protein with the same source, weight, and function of the protein claimed in the ‘915 Patent. The court disagreed, noting that Abbott’s response did not rely on only the information absent from the priority application and that the sequence disclosed in the priority application was sufficient to distinguish the prior art.

Adequate Written Description

The court’s decision is a reminder that there is more than one way to describe an invention to satisfy written description, and, as here, to obtain the benefit of an earlier filing date. Automated DNA sequencers have simplified the sequencing of proteins such that it is common for an application disclosing a protein to disclose its complete amino acid sequence. Nevertheless, where a prior application discloses the same protein as the later filed application, and the prior art application provides sufficient description to characterize the protein and distinguish the prior art, along with a description of how to obtain it from its biological source, the prior application supports the later filed application. Of course, should Abbott assert the claim against an alleged infringer, the separate question of whether the claim is patent eligible as required by 35 U.S.C. § 101, would be an primary issued for consideration.