Following invalidation of independent claim 1 (and a number of other claims) of the sole asserted patent in an inter partes review, Lenovo moved for summary judgment of invalidity of the sole asserted claim of the patent. Lenovo asserted both collateral estoppel and that there was no genuine issue of fact that the claim was obvious. Judge Saris ruled that estoppel applied and granted Lenovo’s motion. The asserted patent related to symmetric multiprocessor or shared-memory multiprocessor systems. Claim 1, which was invalidated by the PTAB, recited the system in some detail; claim 11, the sole asserted claim, added that the system further comprised the microprocessors and the memory device of the system, without further limitation. Notably, claim 11 was not challenged during the IPR. Lenovo asserted that collateral estoppel should apply because Intellectual Ventures could not show that the additional limitations of claim 11 “materially alter the question of invalidity.” Noting that the Federal Circuit had determined that issue preclusion applies to an invalidity finding before the PTAB despite the different standards of proof and of claim construction between the PTAB and district court, Judge Saris determined that estoppel applies. She indicated that the claims need not be identical for estoppel to apply, merely that the issues be the same. As claim 1 had been fully adjudicated, the sole question was whether the differences between claim 1 and claim 11 alter the infringement analysis in a meaningful way – Judge Saris determined that it did not. Claim 1 included limitations on the interfaces between microprocessors and memory devices. Claim 11 merely affirmatively claimed the microprocessors and memory devices. The PTAB had determined that the prior art reference relied upon disclosed microprocessors and memory devices, meaning that the claim did not add anything to the invalidity analysis that had not been determined before the PTAB.