Claim Interpretation and the Festo Case

Claim Interpretation and the Festo Case
Martin J. Adelman

ISBN 9789041199263
Kluwer Law International

In a widely discussed en banc decision, Festo Corporation v. Shoketsu Kinzokukogyo Kabushiki Co., Ltd., subsequently modified slightly by the Supreme Court,2 the Federal Circuit limited the doctrine of equivalents by expanding the reach of the doctrine of prosecution history estoppel. The court did this by extending prosecution history estoppel to all amendments made for reasons of patentability as well as by holding that once it finds that
an estoppel attaches to a limitation, there is no range of equivalents available for that limitation. It was the latter holding that was slightly modified by the Supreme Court.