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Written-Description Requirement Is Not Satisfied by Deposit of Biological Materials

April 02, 2002

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Last Month at the Federal Circuit - May 2002

Judges: Lourie (author), Proust, and Dyk (dissenting)

In Enzo Biochem, Inc. v. Gen-Probe, Inc., No. 01- 1230 (Fed. Cir. Apr. 2, 2002), the Federal Circuit upheld a district court’s decision to grant Gen-Probe, Inc.’s (“Gen-Probe”) motion for SJ that Enzo Biochem, Inc.’s (“Enzo”) patent failed to meet the written-description requirement.

Enzo is the assignee of U.S. Patent No. 4,900,659 (“the Enzo patent”), which claims nucleicacid probes that selectively hybridize to the nucleic acid of Neisseria gonorrhoeae, the bacteria that causes gonorrhea. Previous probes were not able to distinguish N. gonorrhoeae from the similar bacteria N. meningitides, so were limited in their ability to help diagnose gonorrhea. Enzo claimed, as a composition of matter, three probes that were highly selective for N. gonorrhoeae and did not hybridize with N. meningitides. The claims, in relevant part, were to nucleicacid probes that contained a high ratio of nucleotide sequence that hybridized to N. gonorrhoeae compared to a sequence that hybridized to N. meningitides. The specification contained information regarding how the probes were obtained and their approximate lengths, but not their sequences or the means by which the probes were identified. The probes were deposited with the American Type Culture Collection, a repository for biological material.

Enzo sued for infringement, and the Defendants moved for SJ that the claims were invalid for failure to meet the written-description requirement of 35 U.S.C. § 112. The district court granted the motion, concluding that the claimed composition of matter was defined only by its biological activity or function, specifically, its ability to preferentially hybridize to N. gonorrhoeae over N. meningitides and that this definition was insufficient to satisfy the written-description requirement.

On appeal, the Federal Circuit upheld the district court’s finding that describing genetic material in functional terms, i.e., its ability to specifically hybridize to a disease-causing agent, is insufficient to satisfy the written-description requirement. The Court characterized an adequate written description of genetic material as one that includes a structure, formula, chemical name, or physical property. An adequate description may include functional characteristics when they are correlated with the invention’s structure.

Enzo failed to meet this standard because hybridization properties were the only characteristics that described the claimed nucleic-acid sequences. The Court reasoned that Enzo made an invention of a nucleotide sequence to diagnose the presence of the bacteria that causes gonorrhea and broadly claimed it in a circular fashion as any nucleotide sequence that hybridizes with N. gonorrhoeae so as to diagnose its presence.

The Court rejected Enzo’s argument that biological deposits satisfy the written-description requirement. While deposits may enable the invention, the Court concluded, they do not contribute to the description in the patent specification. Also, while deposits may indicate possession of the invention, and one purpose of the written-description requirement is to ascertain that the applicant has possession of the invention on the filing date, possession alone is insufficient to satisfy the requirement.

Judge Dyk dissented, concluding that SJ was inappropriate because there was a genuine issue of material fact involved in whether Enzo’s written description was merely functional or described structural information. Thus, one of ordinary skill in the art may conclude that by describing the degree of hybridization, the specification may adequately describe the structure of the claimed sequences.

He also disagreed with the majority that a biological deposit does not satisfy the writtendescription requirement and criticized the majority for departing from the general rule that an applicant satisfies the written-description requirement by conveying with reasonable clarity that he or she was in possession of the invention.