Biomedino, L.L.C. v. Waters Technology Corp. (Fed. Cir. 2007)

A mean-plus-function claim must be supported by a corresponding structure in the specification, not merely a bare statement that known methods can be used.

The district court found Biomedino’s patent invalid as indefinite under 35 U.S.C. § 112, ¶ 2. The district court held that the claim limitation, “control means for automatically operating valving,” was indefi nite because the specification did not include any structure corresponding to the control means. The Court of Appeals for the Federal Circuit affi rmed on appeal.

The specifi cation disclosed that the invention “may be controlled automatically by known differential pressure, valving and control equipment.” The Court held that this disclosure was insufficient. It held that a bare statement that known techniques or methods can be used does not disclose structure. The Court stated that to conclude otherwise would vitiate the language of the statute requiring corresponding structure, material or acts described in the specifi cation. The Court also stated that the structure must be disclosed in the specification, even if one of skill in the art could implement a structure without such a disclosure.