EAGLE PHARMACEUTICALS INC. V. SLAYBACK PHARMA LLC.

Before O’Malley, Reyna, and Chen. Appeal from the United States District Court for the District of Delaware.

Summary: The disclosure-dedication doctrine precludes infringement under doctrine of equivalents where the patent discloses, but does not claim, an alternative to a claim limitation even when the disclosure relates to a different embodiment than the claimed embodiment.

Eagle Pharmaceuticals Inc. (“Eagle”) filed suit against Slayback Pharma LLC (“Slayback”) for patent infringement under the doctrine of equivalents. Slayback moved for a judgment of non-infringement on the pleadings because Slayback’s accused generic pharmaceutical product used ethanol rather than the claimed propylene glycol. The district court found that the disclosure-dedication doctrine barred Eagle’s claim of infringement under the doctrine of equivalents because the asserted patents disclose, but do not claim, ethanol as an alternative to propylene glycol. Accordingly, the district court granted Slayback’s motion and Eagle appealed.

On appeal, Eagle argued that the disclosure-dedication doctrine does not apply because ethanol was only disclosed as an alternative for propylene glycol in an unclaimed formulation. The Federal Circuit rejected Eagle’s embodiment-level approach, finding that the disclosure-dedication doctrine does not require the disclosure to exactly match the claimed embodiment. Rather, the unclaimed matter need only be disclosed as an alternative to the relevant claim limitation. The Federal Circuit found that ethanol was disclosed as an alternative to propylene glycol. Thus, the Federal Circuit affirmed.

Editor: Paul Stewart

Written by: Christopher L. Lewis & Christie Matthaei