Chapter Seven - AIA’s Modifications to Patent Infringement Defenses

Abstract

The prior user rights and best mode defenses were seldom used prior to the AIA. The AIA amended the statute governing the prior user rights defense, i.e., 35 U.S.C. § 273, however, so that more patent infringement defendants could use the defense against a broader range of patent claims. Notwithstanding these amendments, some of the changes to 35 U.S.C. § 273 actually make it more difficult for defendants to establish that they have prior user rights to an invention. In contrast to Congress’ desire to expand the prior user rights defense, many legislators wanted to completely repeal the best mode requirement from 35 U.S.C. § 112, ¶ 1. While Congress did not go so far as to repeal best mode from the patent statute, the AIA provides several statutory amendments that completely eliminate the possibility of invalidating a patent or rendering it unenforceable based on a failure to disclose the best mode.