Federal Circuit IP

Google LLC v. Hammond Development International, Inc. (Fed. Cir. December 8, 2022)

By Francisco Almeida Published March 3, 2023

Google LLC v. Hammond Development International, Inc. CAFC Opinion No. 21-2218, Decided December 8, 2022 (Moore, Chen, Stoll) (Precedential)

Overview: Collateral estoppel may apply if the claims “use slightly different language to describe substantially the same invention.”

Facts/Procedural Posture:

  • Hammond sued Google for infringing patents ’816 and ’483.
  • In the ’483 patent, claim 18 required certain activities on “one or more application servers.”
  • In the ’816 patent, claim 18 expressly divided the activities between a “first application server” and a “second application server.”
  • Google files IPR’s challenging both patents.
  • After Google filed ’816 petition, Board found all claims of the ’483 unpatentable.
  • Hammond did not appeal the ’483 decision.
  • The Board found claim 18 of the ’816 patent not unpatentable, and Google appealed.

Issue on Appeal: Did the ’483 decision have preclusive effects in the ’816 case?

 Holding: Yes, because:

(1) Google did not forfeit the collateral estoppel argument; it could not have raised the argument in its petition because the preclusive judgment did not yet exist.

(2) Collateral estoppel applied because the only difference between the claims was the number of servers required, which did not materially alter question of patentability.


  • This decision essentially combines several points of law from past cases in a way that one would have expected: (a) collateral estoppel applies in IPR proceedings; and (b) patent claims need not be identical to be subject to collateral estoppel.
  • For family member patents, once issues are litigated and decided in an IPR, collateral estoppel will immediately apply and preclude arguments in parallel ongoing litigation with similar claim language.
  • However, the Federal Circuit did not address when a case is “made final,” because Hammond did not appeal the first case that had the preclusive effect.