Chapter §4.03 Nascent and After-Arising Technology

• Jurisdiction: United States

§4.03 Nascent and After-Arising Technology

How should courts determine if a patent application's disclosure is enabling when the patentee asserts during infringement litigation that its claims encompass embodiments of the invention that did not exist when the patent application was filed? Courts increasingly confront this issue of "after-arising" or "later-arising" technology when dealing with rapidly advancing scientific disciplines, as illustrated by Chiron Corp. v. Genentech, Inc.²⁰⁴ The Chiron patent in suit issued from a continuation-in-part (CIP) application filed in 1995; it was the last in a chain of CIPs relating back to a 1984 parent application.²⁰⁵ The asserted claims of the patent were directed to monoclonal antibodies that bind to human c-erbB-2 antigen (HER2) associated with breast cancer cells. Chiron sued Genentech for infringement based on Genentech's sales of Herceptin, a humanized antibody useful for the long-term treatment of breast cancer.

A district court broadly interpreted Chiron's claims as encompassing not only monoclonal antibodies made using traditional hybridoma (murine) technology, but also those antibodies made using modern genetic engineering techniques. The latter type of antibodies included chimeric antibodies that combine DNA encoding regions from more than one type of species, as well as humanized antibodies that comprise DNA encoding regions primarily from humans (i.e., the type of antibodies used in Genentech's accused product). The district court's interpretation was based in part on an express definition included in written description of the 1995 application (but not present in earlier applications in the CIP chain) that the term "antibody . . . encompasses . . . chimeric antibodies and humanized antibodies."²⁰⁶ On appeal, the Federal Circuit accepted this claim interpretation as correct.

The central dispute at the Federal Circuit became whether Chiron's patent applications filed in the 1980s satisfied the enablement requirement of 35 U.S.C. §112, ¶1 for the claims as broadly interpreted in the litigation. The parties had stipulated before trial that if Chiron could not establish entitlement of the claims to the filing date of any of the earlier 1984, 1985, or 1986 applications in the chain,²⁰⁷ then the patent would be invalid based on intervening prior art. A jury found against Chiron on this issue, concluding that none of the 1984, 1985, or 1986 applications satisfied both the enablement and written description...