Time-Dependent Claim Terms Remain Stuck in the Past

In a decision that is certain to impact both patent prosecution and patent litigation strategies, the U.S. Court of Appeals for the Federal Circuit recently ruled that the literal scope of claims reciting time-dependent claim terms is limited to the technologies existing at the time of the invention. <i>See PC Connector Solutions LLC v. Smartdisk Corp.</i>, 406 F.3d 1359 (Fed. Cir. 2005). Further, the court stated that such claims would not be infringed by later arising technology even under the doctrine of equivalents. This case, in combination with the Federal Circuit's earlier decision in <i>Kopykake Enterprises, Inc. v. The Lucks Company</i>, 264 F.3d 1377 (Fed. Cir. 2001), demonstrates that patent practitioners must be extremely careful when using words such as "conventional," "normal," "standard" or "traditional" in the claims or in specification definitions of claim terms. On the other hand, those accused of infringement should argue for the inclusion of such terms during claim construction, particularly when the accused device comprises technology developed after the invention date of the patent-in-suit.