Patent Owner Precluded From Asserting In Litigation Claims Obtained Through Ex Parte Reexamination

A district court has denied a request to amend patent infringement contentions to add claims obtained through ex parte reexamination after the case had been substantially narrowed through a parallel inter partes review (IPR) proceeding.

In 2014, Plaintiffs sued Defendants in district court for infringement of a patent directed to "mobile tethering" technology. In response, Defendants sought IPR, challenging the patentability of each of the claims that Plaintiffs asserted in their infringement contentions. The court then stayed the patent infringement action pending the Board's resolution of the IPR. Ultimately, the Board found all challenged claims unpatentable except for one. Plaintiffs appealed the Board's decision to the Federal Circuit. While their appeal was pending, Plaintiffs sought ex parte reexamination of the patent at issue in the IPR, and successfully obtained new claims through the reexamination process. With their new claims in hand, Plaintiffs sought