This article provides an in-depth analysis of the Federal Circuit’s en banc decision in Festo Corporation v. Shoketsu Kinzokukogyo Kabushiki Co., Ltd.Overall, “the Federal Circuit failed to expressly limit the application of the doctrine of equivalents to those accused products or processes that were not reasonably foreseeable at the time of the patent, but did limit the doctrine of equivalents by expanding the reach of the doctrine of prosecution history estoppel.” The article notes that the “key issue[s] left unsettled by Festo [are] the status of prosecution history by argument as well as the meaning of an amended limitation.”
GW Paper Series
GWU Law School Public Law Research Paper No. 2013-25; GWU Legal Studies Research Paper No. 2013-25
Martin J. Adelman, Festo and the Doctrine of Equivalents: Implications for Patent Infringement Litigation, 7 Int'l Intell. Prop. & Pol'Y 9-1 (2002).