The U.S. Court of Appeals for the Federal Circuit reversed a priority decision by the Board of Patent Appeals and Interferences (the Board), finding that the priority document failed to meet the written description requirement under § 112. Goeddel v. Sugano, Case Nos. 09-1156, -1157 (Fed. Cir., Sept. 7, 2010) (Newman, J.).

The two interference proceedings related to claims to recombinant human fibroblast interferon (hFIF). "Mature" hFIF produced in the human body has 166 amino acid residues and is formed by cleaving the first 21 amino acids of the hFIF "precursor," which is made up of 187 amino acids. The interference counts were directed to the mature form of hFIF without the 21 amino acid presequence and the DNA sequence encoding the mature hFIF.

Sugano relied on its Japanese application to predate Goeddel’s earliest priority date. The Japanese application disclosed the amino acid sequence of the full-length, 187 amino acid hFIF precursor, but did not explicitly identify the boundary between the 21 amino acid presequence and the 166 amino acid mature hFIF. Instead, the Japanese application cited a journal article which disclosed the first 13 amino acids of the mature hFIF protein.

The Board awarded the priority to Sugano. The Board found that the mature hFIF protein was "readily apparent" in view of the Japanese application’s description of the hFIF precursor and the journal article disclosing the starting point the mature hFIF protein. The Board also held that one skilled in the art "should have been able to envision" the DNA molecule encoding the 166 amino acid mature hFIF protein.

The Federal Circuit disagreed and rejected the Board’s reasoning that the Japanese application constituted constructive reduction to practice because a person of skill in the art could "envision" the invention. The Court held that "in the context of interference priority, [§ 112] requires that the subject matter of the counts be described sufficiently to show that the applicant was in possession of the invention," which, in this case meant the possession of the 166 amino acids, mature and active form of hFIF. The Japanese application, on the other hand, described the 187 amino acid hFIF precursor only, but not the mature hFIF protein or DNA molecules coding the mature hFIF protein. With respect to the Federal Circuit precedents cited by Sugano, including as Enzo Biochem and University of Rochester, the Court noted that these cases did not hold that "envisioning an invention not yet made is a constructive reduction to practice of that invention." Therefore, the Japanese application did not constitute constructive reduction to practice because it failed to meet the written description requirement under §112.

Practice Note: To establish constructive production to practice in an interference proceeding, the priority document must meet two separate and distinct requirements: written description and enablement. While the issue of enablement was not explicitly discussed, the Federal Circuit seemed to be somewhat sympathetic to Sugano’s arguments on enablement. Nonetheless, the Japanese application was insufficient to establish constructive reduction to practice because "possession" of the claimed invention, under the written description requirement, was not shown.