The Evolving Law on Written Description of Nucleotide Sequences

The "written description" requirement of U.S. patent law, set forth in 35 USC 112, requires the patent specification to describe the invention in sufficient detail to demonstrate that the inventors had possession of the subject matter of the claims when the specification was filed. In the field of biotechnology, a number of factors may affect whether a disclosure adequately describes claims drawn to nucleotide sequences, such as the degeneracy of the genetic code, the correlation between a nucleotide sequence and the amino acid sequence it encodes, and homology between genes in the same or different species. The U.S. Court of Appeals for the Federal Circuit has issued several decisions, summarized below, that explain how the written description requirement applies to nucleotide sequence claims. As shown by a recent decision from the Court1 and a decision from the U.S. Patent Office Board of Patent Appeals and Interferences, 2 both discussed below, this area of U.S. patent law is still evolving. Under current law, the written description requirement can be satisfied by setting forth the nucleotide sequence, by depositing in a public depository genetic material containing the nucleotide sequence, by setting forth the amino acid sequence encoded by the nucleotide sequence, or, perhaps, by disclosing functional characteristics of the nucleotide sequence if there is a known or disclosed correlation between function and structure.

One of the first cases to address the written description requirement for nucleotide sequence claims was Fiers v. Revel.3 In that case, the Court determined that the disclosure of a method for isolating the gene at issue did not provide written description of the claimed DNA.4 As the Court explained, "[a]n adequate written description of a DNA requires more than . . . [a] reference to a potential method for isolating it; what is required is a description of the DNA itself."5 The Court reached a similar conclusion in Regents of the University of California v. Eli Lilly & Co., where it held that the disclosure of a method of obtaining cDNA encoding human insulin did not provide written description for a claim requiring the cDNA.6 The Court stated that written description of DNA "requires a kind of specificity usually achieved by means of the recitation of the sequence of nucleotides."7 From those decisions, it was understood that the specification had to set forth the nucleotide sequences in order to provide written description support for nucleotide sequence claims.

The Federal Circuit...