Federal Circuit Rejects Invitation to Extend Scope of Hypothetical Claim Beyond Accused Product for Doctrine of Equivalents Analysis

In Intendis GmbH v. Glenmark Pharmaceuticals Inc., USA, No. 15-1902 (Fed. Cir. May 16, 2016), the Federal Circuit affirmed the district court’s determinations that Intendis’s asserted claims were valid and infringed.

Glenmark appealed the district court’s finding that under the doctrine of equivalents, Glenmark’s accused product infringed Intendis’s asserted claims. The district court applied the function-way-result test and found that components of Glenmark’s product functioned equivalently to components in the asserted claims. Finding no error, the Federal Circuit affirmed.

Glenmark argued that the doctrine of equivalents was precluded because the applied scope of equivalency impermissibly captured prior art. Applying hypothetical claim analysis, the district court rejected Glenmark’s proposed hypothetical claim, which included all potential functional equivalents, and instead, adopted a hypothetical claim that extended the actual claim to literally recite only Glenmark’s accused product. The Federal Circuit found no error with the district court’s analysis.

Glenmark also argued that prosecution history estoppel applied to bar the doctrine of equivalents. The Court found that Applicants’ statements did not clearly and unmistakably disavow claim scope to distinguish prior art and the amendment at issue was not a narrowing amendment made to obtain the patent. Rather, the prosecution history merely included “clarifying” statements and amendments that did not preclude Glenmark’s product. Finding no error, the Federal Circuit affirmed the district court’s determination that prosecution history estoppel does not apply.