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CAFC Updates


By August 11, 2022March 7th, 2024No Comments

The University of Minnesota sued LSI for infringement of U.S. Patent No. 5,859,601 which addresses error rates related to recording data to computer storage devices. LSI petitioned for inter partes review of the ’601 patent and the Board instituted review of certain claims on anticipation theories based on two prior-art references, Okada and Tsang. The Board determined that Okada did not anticipate claims of the ’601 patent and that the Osaka theory was improper as untimely because LSI first raised it at oral argument. On appeal, LSI did not challenge the Board’s determination that LSI’s argument about was improper as untimely, arguing that it was not necessary to challenge the Board’s untimeliness determination because the Board nevertheless reached the merits. However, the CAFC rejects this contention finding that the Board’s timeliness holding constitutes an independent ground for its decision, and LSI forfeited any challenge to the untimeliness holding by failing to challenge it in its opening brief on appeal. As to Tsang, the Board held that the reference was not prior art because it was not “by another” under 35 U.S.C. § 102(e). The CAFC notes that it is undisputed that the unique features of Tsang were irrelevant to LSI’s anticipation arguments, and that the concepts relied upon for anticipation were disclosed in a Seagate Annual Report authored by the inventors of the ’601 patent and merely repeated in Tsang’s Background section. The CAFC finds that the Board properly found that the material in the Tsang patent that exceeded the disclosure of the Seagate Annual Report was not relevant to the anticipation challenge and that summarizing the Seagate Annual Report in Tsang did not make Tsang an inventor of the anticipatory material. The CAFC affirms the Board’s holdings that arguments as to Okada were untimely and that relevant teachings in Tsang were not “by another.”  

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