Patent Law

Pressure Products Medical Supplies, Inc. v. Greatbatch Ltd. (Fed. Cir. 2010)

A five-judge Federal Circuit panel has narrowed the district court's construction of the patentee's means-plus-function claim limitations. This decision might be seen as the foil to the Federal Circuit's recent broad interpretation of a means-plus-function element in Hearing Components v. Shure. Interestingly, Judges Lourie and Rader signed both opinions.

The Pressure Products patent covers a mechanism for inserting and removing catheters and pacemaker leads. The asserted claims include a "means for" facilitating the removal of both a hemostatic valve and a sheath from the disposed catheter. The parties agreed that this limitation should be interpreted as a means-plus-function limitation, but disagreed as to the proper scope of the limitation. Under 35 USC 112p6, a means-plus-function limitation is construed to "cover the corresponding structure, material, or acts described in the specification and equivalents thereof." The district court judge held that the corresponding structure described in the specification used a "score line" to allow the hemostatic valve to separate. During trial (after the close of the plaintiffs case) the Judge updated its definition to include a "linear perforation; slit; slot; tab; line; severing; weakening; or tear that can be partial or complete." The jury found infringement and awarded $1.1 million in past damages.

On appeal, the Federal Circuit reversed.

Claim Construction During Trial: The Federal Circuit first looked at the lower court's procedure and held that the timing of claim construction is in the discretion of the lower court so long as the court works to avoid "surprise and prejudice" that could accompany a late change to the construction.

Scope of the Corresponding Structure: The "score line" structure was discussed in the specification and was clearly a "corresponding structure" to the means-for element. At dispute, however, was the scope of the structure disclosed. Namely, the patent specification included a "laundry list" of prior art references and the district court used the disclosures from those references to expand the definition of a "score line" beyond the structure that was literally described in the specification. On appeal, the Federal Circuit held that approach was wrong and that "the trial court impermissibly expanded the corresponding structure of claim 1 to include structures not described in the specification."

"This court remands for further proceedings in light of the proper construction of the term 'score lines.'"

Writing in Dissent, Judge Newman argued that the patentee should have been allowed to rely upon the disclosures discussed in the specification in order to identify the scope of the disclosed corresponding structure.

Inequitable Conduct: This case also includes an important procedural decision on inequitable conduct ? affirming the district court's refusal to allow the defendant to amend its answer to include an inequitable conduct defense.