Japan's patent office has rejected a Nintendo application related to its Palworld lawsuit, citing a lack of originality. The decision raises questions about the validity of several Nintendo patents describing creature capture systems that are central to the company's complaint against Palworld.

Cattiva vs Pikachu Palworld vs Pokemon fight red background with faint crt lines
A composite image featuring Cattiva from Palworld and Pikachu from Pokemon clashing on a red background. Faint CRT-like lines were added to the image using a color-burning blending mode.

September 19 marked the first anniversary of Nintendo and The Pokemon Company filing a joint patent lawsuit against Palworld developer Pocketpair. The duo alleges that Palworld infringes on three of their patents for creature capture and ridable creature switching. The case, brought in front of the Tokyo District Court, has yet to make its way to trial.

Capcom logo over torn Palworld key art composite
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JPO Says Nintendo's Monster Capture Patent Application Isn't Original

In late October 2025, the Japan Patent Office rejected Nintendo's patent application no. 2024-031879, which is related to the family of creature-capture patents that Palworld is accused of infringing. A JPO patent examiner found that the application lacks originality to be deemed an invention, citing prior art such as Monster Hunter 4, ARK: Survival Evolved, gacha browser game Kantai Collection, Pocketpair's own Craftopia, and even Pokemon GO. All of those were released prior to the December 2021 priority date from the rejected application.

Nintendo patent rejected related to Palworld lawsuit patent family
JPO's illustration of a patent family related to the rejected patent application no. 2024-031879. The Best War Games added labels to illustrate how it's related to the Palworld lawsuit.
JPO / Games Fray

Nintendo's Palworld Lawsuit Suddenly Looks Shakier

Nintendo has 60 days from the date of its rejection notice to amend its application or appeal the decision, giving it until late December 2025 to do so. Since the application isn't cited in the Palworld patent lawsuit directly, its rejection won't have a direct impact on the ongoing case. However, as explained by Games Fray's analyst Florian Mueller, the newly rejected application is a "key building block" in Nintendo's strategy to capture a wide range of creature-capture system implementations. It is the child of patent JP7493117 and the parent of JP7545191, both of which are cited in Nintendo's complaint.

Super Mario vs Pengullet Nintendo vs Palworld red background 2x1 composite
A 2:1 composite depicting Super Mario and Palworld's Pengullet looking like they are about to clash with each other on a red background matching Nintendo's brand palette.

If a central component of a patent family is struck down, related patents may face increased scrutiny or validity challenges. As such, while this rejection does not directly affect the ongoing case, it potentially strengthens Pocketpair's defense strategy that contests the validity of Nintendo's anti-Palworld claims. Presiding Judge Motoyuki Nakashima is not bound by the JPO's decision, final or not, but it might influence his decision-making.

Another patent central to the ongoing dispute is also facing some trouble: a ride-switching system implementation (JP7528390) that Nintendo moved to amend in the middle of the Palworld lawsuit back in July. Amending a patent during active litigation is uncommon, and the vague language used in the proposed amendment was even more unusual, Mueller said at the time. The amendment request delayed proceedings, requiring parts of the case to be reexamined. The lawsuit is now expected to extend well into 2026.

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Top Critic Avg: 71 /100 Critics Rec: 58%
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Released
January 19, 2024
ESRB
T For Teen Due To Violence
Developer(s)
Pocket Pair, Inc.
Publisher(s)
Pocket Pair, Inc.
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WHERE TO PLAY

SUBSCRIPTION
DIGITAL
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Genre(s)
Open-World, Shooter, Survival