Narrow Independent Claims are Not Expanded by the Presence of Broad Dependents


Enzo Biochem Inc. v. Applera Corp., ___F.3d ___ (Fed. Cir. Mar. 16, 2015) (PROST, Newman (dissenting), Linn) (D. Conn.: Arterton) (2 of 5 stars)

Federal Circuit vacates judgment of infringement as resting on an overbroad interpretation of the claims.

The patent related to a nucleotide probe used in detecting certain nucleic acids. The claim required, as part of the probe, a chemical group that was "at least one component of a signaling moiety capable of producing a detectable signal." The claim also required that this group was attached to the rest of the nucleotide structure in such a way as to "not substantially interfere with formation of the signaling moiety."

Such language, interpreted in light of the specification, precluded the claim from reaching probes having a chemical group that was itself a complete signaling moiety. The claim's phrases "component of a signaling moiety" and its bar against interfering with "formation of the signaling moiety" indicated that the moiety must be separately formed. Such interpretation was supported by the specification, which included no disclosure of "direct" detection or use of complete signaling moieties. That three dependent claims involved direct detection did not alter this interpretation because dependent claims cannot broaden independent claims from which they depend. Finally, the district court's reliance on expert testimony to conclude the specification discloses an example of "direct" detection was insufficient because it "does not override our analysis of the totality of the specification, which clearly indicates that the purpose of the invention was directed toward indirect detection, not direct detection." Slip op. at 13-14.

Dissent: Judge Newman thought the claim's reference to "at least one component of a signaling moiety" imposes no requirement of multiple components and must be broad enough to include the dependent claims, which expressly claim embodiments in which the group at issue is a complete signaling moiety. Judge Newman also noted that the district court received testimony concerning appropriate interpretation of the "at least one component" term, and that noted that fact determinations accompanying the district court's construction are entitled to Teva deference.