The Japanese patent office has cast some serious doubt on two of the three patents involved in Nintendo's Palworld lawsuit. These patents concern the monster-catching mechanics at the heart of the dispute with Pocketpair, and it seems officials have noticed that these gameplay systems appeared in titles like Ark, Monster Hunter, and Pocketpair's own Craftopia well before Nintendo tried to patent them. As Florian Mueller writes on game industry legal blog Games Fray, a patent examiner at the Japan Patent Office recently rejected pending application number 2024-031879, which Mueller explains "is a sibling of one of those anti-Palworld 'monster capture' patents and the parent of another." This rejection is non-final, meaning Nintendo will have the choice of either abandoning the patent or modifying it to address the patent office's concerns. So why the sudden rejection? The Japan Patent Office received a third-party submission of prior art, which notes that Ark, Monster Hunter 4, Craftopia, a Japanese browser title called Kantai Collection, and even Pokemon Go all predate – and would thus invalidate – Nintendo's patent. The source behind this prior art submission is anonymous, but Mueller speculates that it could have come from Pocketpair itself. "This Nintendo patent was apparently granted without a patent examiner looking at a single game": IP expert says concerns "hundreds of games" could be affected by Pokemon summoning patent granted amid Palworld lawsuit are "valid" As the Palworld lawsuit rumbles on, Nintendo claims two new patents that could change the way non-Pokemon creature collectors work for good Nintendo's controversial patent on Pokemon mechanics likely won't threaten the likes of Palworld and Persona, as IP expert argues there are already potential ways to invalidate it, including StarCraft This decision in itself doesn't have a direct impact on the lawsuit, which continues regardless. But it does add a new wrinkle to the arguments that may be considered in court. "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," Mueller explains. "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." "Nintendo is so wrong, it hurts" – US IP expert says Nintendo claiming mods don't invalidate its Pokemon patents is "just a loser argument" and a "Hail Mary" in its ongoing legal fight with Palworld.