United States Court of Appeals for the Federal Circuit ______________________

KROY IP HOLDINGS, LLC, Plaintiff-Appellant

v.

GROUPON, INC., Defendant-Appellee ______________________

2023-1359 ______________________

Appeal from the United States District Court for the District of Delaware in No. 1:17-cv-01405-MN, Judge Maryellen Noreika. ______________________

Decided: February 10, 2025 ______________________

PAUL RICHTER, JR., Devlin Law Firm LLC, Wilmington, DE, argued for plaintiff-appellant. Also represented by TIMOTHY DEVLIN.

THOMAS LEE DUSTON, Marshall, Gerstein & Borun LLP, Chicago, IL, argued for defendant-appellee. Also rep- resented by CHELSEA MURRAY, RAYMOND R. RICORDATI, III. ______________________

Before PROST, REYNA, and TARANTO, Circuit Judges. REYNA, Circuit Judge. Case: 23-1359 Document: 43 Page: 2 Filed: 02/10/2025

2 KROY IP HOLDINGS, LLC v. GROUPON, INC.

Kroy IP Holdings, LLC sued Groupon, Inc. in the United States District Court for the District of Delaware alleging patent infringement. Groupon moved to dismiss Kroy’s operative complaint, arguing that Kroy was collat- erally estopped from alleging infringement of the asserted claims based on two prior inter partes review decisions of the Patent Trial and Appeal Board. Both of the Board’s prior decisions involved the same patent, but claims other than the asserted claims. The district court granted Groupon’s motion to dismiss. Kroy timely appeals. For the following reasons, we reverse and remand. BACKGROUND Kroy IP Holdings, LLC (“Kroy”) owns U.S. Patent No. 6,061,660 (“’660 patent”), which relates to providing incen- tive programs over a computer network. ’660 patent, Ab- stract. In October 2017, Kroy sued Groupon, Inc. (“Groupon”) in the United States District Court for the Dis- trict of Delaware, alleging that Groupon infringed 13 ex- emplary claims of the ’660 patent. J.A. 1014. In October 2018, Groupon filed two inter partes review (“IPR”) peti- tions challenging 21 claims of the ’660 patent. Groupon, Inc. v. Kroy IP Holds., LLC, No. IPR2019-00044, 2020 WL 1900398 (P.T.A.B. Apr. 16, 2020) (“’044 IPR”); Groupon, Inc. v. Kroy IP Holds., LLC, No. IPR2019-00061, 2020 WL 1900402 (P.T.A.B. Apr. 16, 2020) (“’061 IPR”). After Groupon’s IPR filing deadline had passed, Kroy amended its complaint to allege infringement of additional claims, many of which were not included in Groupon’s IPR peti- tions. J.A. 1925–26. In April 2020, the Patent Trial and Appeal Board (“Board”) found all 21 of the challenged claims unpatentable (the “Unpatentable Claims”). ’044 IPR, 2020 WL 1900398, at *1; ’061 IPR, 2020 WL 1900402, at *1. Kroy appealed the Board’s final written decisions, and in June 2021, this court affirmed via Federal Circuit Rule 36 (“Rule 36”). Kroy IP Holds., LLC, v. Groupon, Inc., 849 F. App’x 930 (Fed. Cir. 2021). Case: 23-1359 Document: 43 Page: 3 Filed: 02/10/2025

KROY IP HOLDINGS, LLC v. GROUPON, INC. 3

In March 2022, Kroy filed a second amended complaint alleging infringement of 14 claims of the ’660 patent (the “Newly Asserted Claims”), none of which were at issue in the IPR proceedings. J.A. 2457; J.A. 2472. In response, Groupon filed a motion to dismiss pursuant to Federal Rule of Civil Procedure 12(b)(6), arguing that the Board’s prior IPR rulings on the Unpatentable Claims collaterally es- topped Kroy from asserting the Newly Asserted Claims. The district court agreed with Groupon and granted its motion to dismiss with prejudice in December 2022. Kroy IP Holds., LLC v. Groupon, Inc., No. 17-1405-MN-CJB, 2022 WL 17