Means Plus Function Claims Still Limited to Structure Described in Specification

The Court of Appeals for the Federal Circuit ("CAFC") this week in RESTAURANT TECHNOLOGIES, INC. v. JERSEY SHORE CHICKEN and KLEE’S BAR & GRILL, have essentially held that means plus function claims cover the structure as disclosed in the specification.

The case involved an invention that relates to the supply and disposal of cooking oil for use with restaurant fryers. Restaurant Technologies, Inc. ("RTI") owns the patent in suit, US Patent 5,249,511 ("the '511 patent"), that is directed to a system for the distribution, filtering, removal, and disposal of cooking oil.  The system enhances safety to workers and efficiency to deep frying operations.

The primary disputed claim term involved a squeezable trigger valve, which RTI argued would be equivalent to a lever, button, or some other structure, including either the pump or the dipstick with a triggering button of the accused product.   The CAFC disagreed, "although the dipstick assembly, in conjunction with the pump, may perform the identical function as the squeezable trigger valve, the differences between the dipstick assembly plus a pump on the one hand, and a squeezable trigger valve with a nozzle, on the other, are not insubstantial. For example, the dipstick assembly and pump are activated with a push button on the dipstick assembly that energizes the pump; fluid pressure in the line then overcomes a spring-loaded check valve to pour into the fryer. The accused system thus uses a pump and fluid pressure to overcome a check valve, whereas the patent claims a valve that is squeezed. Thus, no reasonable fact finder could have found that the dipstick assembly, alone or in conjunction with the pump, meets the limitations of claim 1, paragraph (d)(iii)."

Additional claim terms were in dispute but all were construed according to the specific structure and then evaluated for equivalence based on the insubstantial difference test.  Having found insubstantial differences between the claimed elements in the '511 patent and the accused device, the District Court Judgment of Non-infringement was affirmed and we are again reminded that means plus function format claims are still limiting claims.