The Court of Appeals For The Federal Circuit Finds Collateral Estoppel Applies Between Two IPR Proceedings And Invalidates Claims
On December 8, 2022, the United States Court of Appeals for the Federal Circuit (CAFC) found that the Patent Trial and Appeal Board’s (PTAB) finding that certain patent claims were unpatentable in an inter partes review (IPR) proceeding renders a similar claim of a related patent unpatentable based on collateral estoppel. Google LLC v. Hammond Dev. Int’l, Inc., No. 2021-2218 (Fed. Cir. Dec. 8, 2022).
Google petitioned for IPR of all claims of Hammond’s U.S. Patent No. 10,270,816 (the “’816 patent”). On June 4, 2021, the Board held that only claims 1–13 and 20–30 would have been obvious. Google had also previously petitioned for IPR of Hammond’s U.S. Patent No. 9,264,483 (the “’483 patent”). The ’816 and ’483 patents are related and share the same specification. On April 12, 2021, the PTAB issued a final written decision determining that all challenged claims of the ’483 patent would have been obvious based on the same prior art combinations as the IPR of the ’816 patent.
Google appealed the PTAB’s determination that claims 14–19 of the ’816 patent are not unpatentable, arguing, among other things, that the PTAB’s determination that claim 18 of the ’483 patent is unpatentable renders claim 18 of the ’816 patent unpatentable based on collateral estoppel.
A party seeking to invoke collateral estoppel must show: (1) the issue is identical to one decided in the first action; (2) the issue was actually litigated in the first action; (3) resolution of the issue was essential to a final judgment in the first action; and (4) the party against whom collateral estoppel is being asserted had a full and fair opportunity to litigate the issue in the first action. In re Freeman, 30 F.3d 1459, 1465 (Fed. Cir. 1994). Only the first requirement was in dispute.
Collateral estoppel requires that the issues of patentability be identical, rather than the patent claims be identical. Thus, collateral estoppel may apply even if the patent claims use slightly different language so long as the differences do not materially alter the question of invalidity. Invalidated claim 18 of the ’483 patent required certain activities on “one or more application servers,” and claim 18 of the ’816 patent divided the activities between two application servers. The PTAB found that this difference did not materially alter the question of invalidity, crediting Google’s expert testimony that a person of ordinary skill in the art would have found it obvious to host each of the applications in the prior art reference, Gilmore, on separate servers. The PTAB explained that “distributing software applications across multiple servers was well known to the artisan.”
Accordingly, the CAFC found that the issues of patentability of claim 18 of the ’483 patent and claim 18 of the ’816 patent are identical, and held that collateral estoppel applies.