Last week, the United States Court of Appeals for the Federal Circuit issued an opinion in Eagle Pharmaceuticals Inc. v. Slayback Pharma LLC, 2019-1924 (May 8, 2020). Eagle sued Slayback for infringing four patents covering Eagle’s BELRAPZO® cancer treatment drug under the doctrine of equivalents (DOE). The asserted patent claims all included as a limitation “a pharmaceutically acceptable fluid comprising a mixture of polyethylene glycol and propylene glycol.” Slayback’s accused products employed ethanol instead of propylene glycol, which Eagle asserted was an insubstantial difference. Slayback moved for judgment on the pleadings under Federal Rule of Civil Procedure 12(c), arguing that the disclosure-dedication doctrine barred Eagle’s infringement claim because the asserted patents disclose, but do not claim, ethanol as an alternative to propylene glycol. The district court granted Slayback’s motion. Eagle appealed.
The Federal Circuit affirmed. On the merits, the Court rejected Eagle’s argument about claimed and unclaimed embodiments. Specifically, Eagle argued that the asserted patents do not disclose ethanol as an alternative to propylene glycol for the claimed compositions, but rather did so only for a different unclaimed embodiment. Eagle argued that a skilled artisan would, therefore, not understand ethanol to be an acceptable alternative to propylene glycol in composition of the asserted claims. The Court explained that the disclosure-dedication doctrine does not require that the disclosure exactly matches the claimed embodiment; it requires only that the specification disclose the unclaimed alternative in the context of the relevant claim limitation. The Court concluded that the specifications’ repeated disclosure of ethanol as an alternative “pharmaceutically acceptable fluid” did so. The Court also rejected a procedural challenge raised by Eagle. Specifically, Eagle argued that the district court erred in failing to consider an expert declaration it submitted, which it asserted created a fact dispute and rendered judgment on the pleadings inappropriate. The Court explained it is within the district court’s discretion to decide whether to consider evidence outside the pleadings on a 12(c) motion. The Court concluded that the district court did not abuse its discretion here in declining to consider Eagle’s expert declaration because, in this case, with or without expert testimony, the only reasonable inference is that a skilled artisan would understand the patents to disclose ethanol as an alternative.