Again answering the often-asked question of when a structure is "unitary," the U.S. Court of Appeals for the Federal Circuit has held that a disclaimer during prosecution extended broadly to the distinguished prior art, in fact, across all of the embodiments disclosed in the prior art. Sentry Protection Prods., Inc. v. Eagle Mfg. Co., Case No. 04-1392 (Fed. Cir., March 11, 2005) (Prost, J.).

Sentry sued Eagle for infringement of its patents on barriers that protect structural columns and supports from being damaged when they are hit by cars, while reducing damage to the impacting car and its driver.

One of the elements of the claimed invention is essentially a bumper, which the patent refers to as "impact protection components." The key dispute was whether the prior art had devices made up of a plurality of such bumpers where each bumper was a "single unitary part." Sentry added the "single unitary part" limitation to distinguish the prior art "multi-component … assembly" (i.e., a bumper made up of an inner tube and a protective shell). The Federal Circuit held Sentry thereby expressly disclaimed multiple-piece bumpers. The cited prior art reference disclosed bumpers comprising multiple pieces that could be separated and bumpers in which the multiple pieces were joined in such a way that they could not be separated. Accordingly, the Federal Circuit held bumpers with multiple pieces to be disclaimed, whether or not the pieces were separable or inseparable. The Federal Circuit thus affirmed the district court’s claim construction that "the impact protection component is a single part, which is complete by itself without additional pieces."

Applying this construction, the Federal Circuit went on to hold both of the asserted claims anticipated by a different reference disclosing a frame and mounting brackets holding two hollow cushion bumpers in place. The Court found each of the cushions met the limitation "single unitary part."

Practice Note: Perhaps foreshadowing the outcome of the much-anticipated en banc Phillips v. AWH Corp. case, by broadly applying the disclaimer doctrine across all embodiments disclosed in the distinguished prior art, this decision highlights the significance that this Federal Circuit panel would give to the intrinsic claim construction evidence.

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