Written Description Requirement Not Satisfied Under Principles of Inherency

In affirming an award of priority by the U.S. Patent and Trademark Board of Appeals and Interferences (the Board), the U.S. Court of Appeals for the Federal Circuit held that a product that is inherently produced by a disclosed process does not satisfy the written description requirement for claims directed to the product when one of skill in the art, reading the application, would not have been aware that the product is produced. Chen v. Bouchard, Case No. 03-1037 (Fed. Cir. Oct. 22, 2003).

The Board declared an interference between U.S. Pat. No. 5,254,580 to Chen, which claimed priority back to July 1, 1992, via a continuation in part, and a pending application of Boucher that had a priority date of December 9, 1992. Chen’s 1992 parent application disclosed a process to produce taxol derivatives and precursors of taxol. The disclosed method did not explicitly state that cyclopropataxols were produced as required by the interference count. Chen argued that cyclopropataxols were