Nintendo's patent application, split-filed in February 2026, has been rejected by the Japan Patent Office. Given that this technology sits at the heart of the ongoing legal dispute involving 'Palworld', this development is expected to have a significant impact on the case.

On April 21, the Japan Patent Office released a notice of rejection for patent application '2026-19762', a joint filing from Nintendo and The Pokémon Company. Tracing its roots back to an initial filing on December 22, 2021, Nintendo had carved out a specific system for a split application on February 10.

The patent in question covers a system for capturing field characters by tossing items within a virtual space. The core of the patent targets game programs running on devices equipped with touch panels, allowing players to capture creatures while roaming the field or during combat. It calculates success rates for capture items and, upon a positive outcome, assigns the character to the player's ownership. It appears to be aimed at touchscreen-based titles, including the mobile version of 'Palworld'.

The examiner at the Japan Patent Office rejected the application, citing a lack of inventive step under patent law. They pointed out that a 3D fan game from 2013, 'Pokémon Generations', already featured character movement, capture mechanics, and summon-based combat. Furthermore, the office noted that games like 'ARK' and 'PUBG'—which transitioned from PC to mobile—already utilized these mechanics, rendering the patent a mere combination of widely known industry techniques.

This rejection is likely to impact Nintendo's patent infringement lawsuit against 'Palworld' developer Pocketpair. Since the rejected patent directly relates to the core system of 'Palworld' where players capture and summon monsters to fight, the loss of this foundational legal argument may put Nintendo in a disadvantageous position.

Meanwhile, in April, Nintendo also faced a setback in the US regarding their patent for a 'system to summon auxiliary characters to battle enemies,' which was also rejected in its entirety. The US Patent and Trademark Office reached a similar conclusion, determining that the submission failed to offer genuine innovation, instead relying on a synthesis of pre-existing technologies.