In construing a claim, a district court may not import limitations from the specification into the claim. Rather, its task is simply to give meaning to the limitations actually contained in the claim.

The patentee filed multiple lawsuits against the accused infringers, alleging infringement of a patent related to counterweights for vibratory pile drivers. The patentee appealed two decisions granting summary judgment of non-infringement—one from the District Court for the Eastern District of Virginia and the other from the District Court for the Northern District of California. In each action, the parties disputed the meaning of certain claim terms. While the district courts construed the terms “eccentric weight portion” and “insert-receiving area” differently, both courts granted summary judgment of non-infringement on the basis of their respective constructions.

On appeal, the patentee argued that summary judgment was improper because the district courts misconstrued the claim terms at issue. The Federal Circuit affirmed the claim construction of the Virginia district court and reversed the construction of the California district court insofar as it differed from the Virginia district court’s construction.

In construing claims, a district court’s task is simply “to give meaning to the limitations actually contained in the claims.” While it may look to the specification to “inform” its interpretation of a claim term, it may not import a limitation from the specification into the term. The Virginia district court properly construed each of the claim terms at issue. The California district court, however, improperly imported limitations from the specification into its construction of “eccentric weight portion” and “insert-receiving area.” Accordingly, the Federal Circuit reversed the California district court's construction of these terms.

A copy of the opinion can be found here.