In Juno Therapeutics, Inc. v. Kite Pharma, Inc., [2020-1758] (August 26, 2021), the Federal Circuit reversed the jury verdict that claims of U.S. Patent No. 7,446,290, were not invalid for lack of written description, because it was not supported by substantial evidence.
A specification adequately describes an invention when it “reasonably conveys to those skilled in the art that the inventor had possession of the claimed subject matter as of the filing date.” What is required to meet the written description requirement “varies with the nature and scope of the invention at issue, and with the scientific and technologic knowledge already in existence.” A mere wish or plan for obtaining the claimed invention is not adequate written description. The Federal Circuit said that for genus claims using functional language, like the ones at issue in the case, the written description “must demonstrate that the applicant has made a generic invention that achieves the claimed result and do so by showing that the applicant has invented species sufficient to support a claim to the functionally-defined genus.”
On appeal Kite argued that the claims cover an enormous number (millions of billions) of candidates, only a fraction of which satisfy the functional binding limitation for any given target, and that the written description does not meet the written description requirement for this functional binding limitation. Kite argues that the asserted claims are invalid for failing to satisfy the written description requirement because the patent discloses neither representative species nor common structural features of the claimed genus to identify which combinations would function as claimed.
The Federal Circuit agreed that no reasonable jury could find the ’190 patent’s written description sufficiently demonstrates that the inventors possessed the full scope of the claimed invention. The Federal Circuit said that the ’190 patent’s written description fails to provide a representative sample of species within, or defining characteristics for, the expansive genus claimed. The Federal Circuit explained that this did not mean that a patentee must in all circumstances disclose the nucleotide or amino acid sequence of the claimed sequences to satisfy the written description requirement when such sequences are already known in the prior art. But the written description must lead a person of ordinary skill in the art to understand that the inventors possessed the entire scope of the claimed invention.
The Federal Circuit concluded that substantial evidence does not support the jury’s verdict in Juno’s favor on the issue of written description, and reversed.