The Patent Trial and Appeal Board (PTAB) issued a final written decision finding certain challenged claims of U.S. Patent No. 6,432,586 unpatentable under 35 U.S.C. § 103(a). In doing so, the PTAB also ruled on several motions to exclude evidence.

With respect to the obviousness determination, the petitioner moved to exclude materials from third-party websites (e.g., LG Chem) that patent owner’s expert relied on as evidence of commercial success. The petitioner argued that Rule 703 of the Federal Rules of Evidence is not intended to allow the admission of otherwise inadmissible hearsay evidence. Patent owner responded that it is proper for an expert to form an opinion based on otherwise inadmissible evidence. The PTAB denied petitioner’s motion, stating that Rule 703 allows the disclosure of evidence relied upon in forming an expert opinion if the “probative value in helping the jury evaluate the opinion substantially outweighs [its] prejudicial value.” And it held that the contested evidence have substantial value in evaluating the opinion of patent owner’s expert.  Interestingly, the PTAB also indicated a lower threshold for admissibility compared to district court proceedings: “because the board is not a lay jury, and has significant experience in evaluating expert testimony, the danger of prejudice in this proceeding is considerably lower than in a conventional district court trial.”

Although the PTAB allowed Patent Owner’s evidence of commercial success, it was not persuasive. The PTAB ruled that the third-party websites identified numerous desirable features, in addition to the claimed features, of their lithium-ion batteries. As a result, the PTAB determined that the patent owner had not established a sufficient nexus between certain contested claims and the purported evidence of commercial success.

SK Innovation Co., Ltd. v. Celgard, LLC, IPR2015-00679, Paper No. 58 (PTAB Sept. 25, 2015).