Federal Circuit, March 24, 2014, 2013-1239

Brain Life LLC, a non-practicing entity, owns the rights to Patent 5,398,684, which were assigned to it by Medical Instrumentation Diagnostics Corp. ("MIDCO"). The District Court, (Southern District of California) had dismissed the suit by Brain Life against Elekta based on claim and issue preclusion, since the Elekta's devices at issue had been found not to infringe in an earlier proceeding. The Federal Circuit affirmed the District Court's dismissal of the suit, however it did so based on the Kessler Doctrine.

In 1997, MIDCO sued Elekta alleging that certain Elekta products infringed the '684 patent. During the proceedings, MIDCO volunteered to not proceed with respect to the method claims. The Trial Court found that Elekta's product infringed a single apparatus claim and awarded MIDCO approximately $16M in damages. The finding of infringement was later reversed by the Federal Circuit, which also vacated the damages award and remanded to the district court to enter judgment of noninfringement as a matter of law in favor of Elekta.

In the instant case, the District Court held that Brain Life was barred from litigating the method claims of the '684 patent because MIDCO had chosen not to pursue them when it had the opportunity in the previous suit and because there was no material difference in the products accused of infringement in the previous suit. In the Federal Circuit, O'Malley J. citing the Kessler Doctrine, stated, "once the accused devices in the MIDCO litigation were adjudged to be non-infringing with respect to the asserted claims and judgment was entered as to all of the claims, Elekta was free to continue engaging in the accused commercial activity as a non-infringer." Infringement by Elekta's products relating to acts that took place after the entry of final judgment in the first MIDCO suit were barred by the Kessler doctrine by virtue of the final judgment in the first suit where all of the claims could have been asserted by MIDCO. Therefore, the Federal Circuit affirmed the District Court's dismissal, but for different reasons.