Nintendo’s Character-Summon Patent Rejected in Full: All 26 USPTO Claims Refused

In November 2025, USPTO Director John A. Squiers issued a Director-Initiated Reexamination order against Nintendo’s patent US12403397B2, granted in September 2025, which covers a game mechanic in which a player summons a separate character to fight on their behalf. The reexamination resulted in all 26 claims receiving rejection notices based on prior art. USPTO observers have described the Director’s intervention as “unprecedented since 2012,” drawing significant attention from the global gaming industry.

Prior Art: Four Patents That Blocked the Claims

The USPTO Director identified four prior-art references that collectively undermine all 26 claims. The earliest is the Yabe patent (Konami, 2002), which discloses mechanics for a sub-character automatically or manually assisting a main character — a structure substantially similar to the “summon a fighter” concept at issue. Nintendo’s own Taura patent (2020) and Motokura patent (2022) also disclose analogous game mechanics, as does Bandai Namco’s Shimomoto patent (2020). Together, these four references were deemed sufficient to reject all claims under 35 U.S.C. §§ 102 and 103 for lack of novelty or obviousness.

Section 101 and the Broader Challenge for Game Mechanic Patents

While the rejection here rests on prior art rather than patent eligibility, game mechanic patents in the United States face an additional structural challenge under 35 U.S.C. § 101. Since the Supreme Court’s 2014 ruling in Alice Corp. v. CLS Bank, courts and the USPTO have consistently held that software implementing an “abstract idea” is patent-ineligible. Game rules and mechanics are frequently characterized as abstract ideas, making it difficult for such patents to survive the Alice two-step framework. The USPTO’s 2019 Revised Guidance offered some relief, but eligibility rejections remain a persistent risk for game mechanic claims — even after overcoming prior-art hurdles.

Current Status: Nintendo Has Two Months to Respond

The office action is a Non-Final rejection, meaning Nintendo retains the right to submit a response — arguments, claim amendments, or both — within two months of the action date (extendable by petition). Narrowing the claims to distinguish all four prior-art references would require substantial limitation, and whether any commercially meaningful claim scope can be preserved remains an open question.

Implications for Nintendo’s Patent Strategy

The patent in question was reportedly a key basis for Nintendo’s September 2024 lawsuit against Pocketpair, the developer of Palworld. The rejection of all 26 claims could materially affect the trajectory of that litigation. More broadly, this case illustrates that even the world’s most experienced game IP holders can find their patents undermined when prior art is surfaced from legacy titles. For game developers and their counsel, it reinforces the importance of comprehensive prior-art searches before filing — and the need to evaluate both § 101 eligibility and prior-art risk from the outset of any patent strategy.