Festo Corporation v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., A/K/A Smc Corporation, and Smc Pneumatics, Inc.

I concur in and join the opinion and judgment of the court. It is a second-best solution to an unsatisfactory situation. Under our preexisting law, a count for infringement under the doctrine of equivalents became a routine part of a patent infringement suit. The game was to convince the trier of fact, typically a jury, that even if an accused product1 does not infringe the claims as written, the claimed invention and the accused product have only “insubstantial differences,” a wonderfully indeterminate phrase, lending itself to making eyery decision under the doctrine an individualistic…