T-Mobile US, Inc. v. KAIFI LLC

T-Mobile US, Inc. v. KAIFI LLC The Federal Circuit held that it lacked appellate jurisdiction because the dispute turned on state-law contract interpretation and did not necessarily raise a substantial patent-law issue under Gunn. The court transferred the appeal to the Fifth Circuit. Patent-related settlement disputes do not automatically belong in the Federal Circuit, even when the contract references reexamination results and the parties frame the dispute around claim scope or inequitable-conduct concepts. Transferred to the United States Court of Appeals for the Fifth Circuit; parties to bear their own costs. The settlement required an additional payment if any “Asserted Claim survives the EPR”; the PTO later confirmed several asserted claims patentable without amendment. T-Mobile argued that “survives” required more than formal confirmation in the reexamination certificate, including whether KAIFI changed claim-scope positions or engaged in inequitable conduct during the EPR. The Federal Circuit held that KAIFI’s breach-of-contract theory could be resolved by ordinary contract interpretation—e.g., by looking to the reexamination certificate—without deciding any patent-law issue. The court also found no substantial federal patent issue: the dispute was backward-looking, fact-bound, private, and unlikely to affect patent-law uniformity or PTO administration. Because the district court had diversity jurisdiction and the case came from the Eastern District of Texas, the proper appellate forum was the Fifth Circuit. precedential standing / jurisdiction claim construction attorney fees / sanctions precedential standing / jurisdiction claim construction attorney fees / sanctions precedential standing / jurisdiction