Japan Patent Office rejects Nintendo application relevant to Palworld dispute, cites games like ARK as prior art after third-party submission
https://archive.ph/voSD3
>Context: Nintendo’s patent infringement litigation against Palworld maker Pocketpair is still ongoing. Nintendo clings to all sorts of theories to defend its patents against Pocketpair’s invalidity arguments, including the position that mods should not count as prior art (September 16, 2025 games fray article). It may be part of a PR strategy to distort the reality of who was first to create what, given that Nintendo itself is apparently developing a Pokémon spinoff with Palworld-like elements (October 14, 2025 games fray article).
>What’s new: A decision called Office action, made by a patent examiner of the Japan Patent Office (JPO) less than two weeks ago, casts serious doubt on the validity of two of Nintendo’s three Japanese patents-in-suit. This is about pending application no. 2024-031879 that is a sibling of one of those anti-Palworld “monster capture” patents and the parent of another. It has been rejected (on a non-final basis) because the patent office, after a third-party submission of prior art, determined that the claimed technique lacked an inventive step. The prior art references cited by the JPO include various games that predate Nintendo’s December 2021 priority date, among them Studio Wildcard’s ARK, Capcom’s Monster Hunter 4, Pocketpair’s Craftopia, a Japanese brower game named Kantai Collection (Web Archive link), and Pokémon GO.
>Direct impact:
>Nintendo now faces the choice between abandoning the embattled patent application or, which is the more likely next step, trying to persuade the patent examiner based on a modified patent application with amended claims. Also, when the process at the patent office is over, an appeal to a specialized court named Intellectual Property High Court (IPHC) is possible. The Japanese patent prosecution process has even been described as an “endless loop” (World Intellectual Property Report). But the fact that the patent examiner is now looking at real-world games as opposed to just patent documents and articles considerably ups the ante for Nintendo.
>For the avoidance of doubt, even if this Nintendo application fails, there is no direct impact on the Palworld patent case. However, see the next section…
Wider ramifications:
>The (non-finally) rejected patent application is a key building block of Nintendo’s “monster capture” patenting strategy that took aim at Palworld after its early-2024 release. It has the same parent application as JP7493117 and is the parent of JP7545191, both of which Nintendo is asserting against Palworld (February 6, 2025 games fray article). Just like the applications that led to the patents-in-suit, this application was filed shortly after Palworld’s release.
>An issue facing a central member of a patent family is often indicative of validity problems facing other memers.
>The overlap between the invalidity contentions underlying the rejection and Pocketpair’s defenses (April 18, 2025 games fray article) makes it plausible that Pocketpair could be behind an April 2025 submission to the JPO in connection with this Nintendo patent application.
>A JPO decision, much less a non-final one, is not binding on Presiding Judge Motoyuki Nakashima, who is handling the Nintendo v. Pocketpair case. But judges are legally trained and tend to have respect for the determinations made by patent examiners, who are technically trained. Pocketpair might try to point the Tokyo District Court to relevant developments in the JPO. In the U.S., that would be called a request for judicial notice, and can influence decisions. We assume that there will not be a decision of any kind in the infringement case before next year. The proceedings have been delayed, presumably due to what the next bullet point mentions:
Nintendo’s third patent-in-suit is also in trouble: they felt forced to seek a modification in the middle of litigation (July 16, 2025 games fray article).