Functional Claiming Under U.S. Patent Law

Abstract

Functional claim limitations can be useful for providing robust patent coverage, protecting what has been invented as well as variations therein. Patents employing such limitations can be useful for developing a portfolio that carves out a significant patent landscape, protecting one’s intellectual property and providing a strong negotiation position for both licensing and litigation purposes. Under U.S. law, uncertainty surrounding functional claim limitations has generated tension due to seemingly contradictory positions taken by both the courts and the U.S. Patent & Trademark Office (USPTO). These considerations are applicable to a variety of technologies, and are particularly interesting for computer-implemented inventions.