Short Summary: Claims that emerge from reexamination do not in and of themselves create a new cause of action.

Case: Senju Pharma, Co., Ltd. v. Apotex, Inc., No. 2013-1027 (Fed. Cir. Mar. 31, 2014) (precedential). On appeal from D. Del. Before Newman, Plager, and O’Malley.

Procedural Posture: Plaintiff patentee appealed grant of summary judgment finding patent invalidity. CAFC affirmed.

  • Res Judicata: Before that district court’s entry final judgment of invalidity, Plaintiff initiated an ex-parte reexamination with the USPTO to narrow its patent’s claims. Upon issuance of the reexamination certificate, and still before the district court’s entry of final judgment, plaintiff filed a second lawsuit against defendant alleging infringement of the narrowed claims of the same patent found invalid at the first trial. Although the parties agreed that the first lawsuit met the first two requirements for claim preclusion, namely, a final judgment on the merits and the same parties or privies, they differed as to whether amended claims constituted the same cause of action. Applying its own precedent, the Federal Circuit affirmed the district court’s finding that plaintiff’s infringement claims were barred by the doctrine of claim preclusion. Statutory requirements for reexamination under 35 U.S.C. § 305 require that an amended claim fall within scope of the original claims, and, therefore, “claims that emerge from reexamination do not in and of themselves create a new cause of action that did not exist before.”

O’Malley, dissenting:

  • Res Judicata: Although the amended claims may not be broader in scope, they may grant broader rights. For example, in the instant case, plaintiff’s original claims were determined to be invalid, but its amended claims have a presumption of validity. Therefore, the two lawsuits do not constitute the same cause of action. In Aspex Eyewear, Inc. v. Marchon Eyewear, Inc., 672 F.3d 1335 (Fed. Cir. 2012), the Federal Circuit ruled that amended claims following a reexamination were precluded from a second lawsuit against the same product, because the accused products were already determined to not infringe and the scope of the claims could not be broadened in reexamination. In contrast, plaintiff’s patent has undergone a significant transformation with respect to patent validity.