Nintendo’s legal battle against Palworld developer Pocketpair hit a major roadblock on October 28, 2025, when the Japan Patent Office formally rejected one of Nintendo’s patent applications central to the ongoing lawsuit. Application number 2024-031879, part of Nintendo’s monster-capture patent family, was denied after a third-party submission presented extensive prior art including ARK Survival Evolved, Monster Hunter 4, Craftopia, Kantai Collection, and even Nintendo’s own Pokemon GO as examples proving these mechanics existed long before Nintendo tried to patent them.
The Patent Family Connection
What makes this rejection particularly significant is how the denied application fits into Nintendo’s broader patent strategy. According to legal analyst Florian Mueller from GamesFray, application 2024-031879 sits directly between two patents Nintendo is actively asserting against Palworld in Tokyo District Court. It shares the same parent application as JP7493117 and serves as the parent of JP7545191, creating what Mueller describes as a sibling-parent structure within the patent family tree.
This interconnected relationship means a rejection of one patent based on lack of originality raises serious questions about the validity of its relatives. If the Japan Patent Office finds that 2024-031879 lacks an inventive step and cites existing games as prior art, the same reasoning could logically apply to the related patents Nintendo is wielding in court against Pocketpair.
The timing of these applications is also noteworthy. All three were filed shortly after Palworld’s explosive February 2024 release, suggesting a reactive patenting strategy specifically targeting the breakout indie hit rather than protecting genuinely novel innovations Nintendo developed years earlier.
Understanding the Patent Family Tree
- JP7493117 – Granted patent currently asserted against Palworld in lawsuit
- 2024-031879 – Newly rejected application citing lack of inventive step
- JP7545191 – Granted patent also asserted against Palworld in lawsuit
- All three filed March 2024, shortly after Palworld’s February launch
- December 2021 priority date on rejected application
- Multiple games predate this priority date with similar mechanics
The Prior Art That Killed the Patent
The Japan Patent Office’s October 22, 2025 notice of refusal explicitly cited multiple games that implement mechanics described in Nintendo’s application. ARK Survival Evolved, which released in 2015, features creature-taming systems using thrown items remarkably similar to what Nintendo attempted to patent. Monster Hunter 4 from 2013 includes capturing monsters using specific items and making success determinations based on various factors.
Perhaps most damaging to Nintendo’s case, the examiner cited Pocketpair’s own game Craftopia, which launched in early access in 2020, a full year before Nintendo’s December 2021 priority date. Craftopia features creature-capturing mechanics using thrown Pal Spheres in ways nearly identical to both Pokemon and Palworld. The browser game Kantai Collection and Pokemon GO itself also appeared in the prior art submission.
The anonymous third-party who submitted this prior art clearly did their homework. By documenting multiple games across different developers and platforms implementing these mechanics before Nintendo’s claimed invention date, they built an overwhelming case that these systems represent standard industry practice rather than novel innovation worthy of patent protection.
| Game | Release Date | Relevant Mechanic | Developer |
|---|---|---|---|
| Monster Hunter 4 | September 2013 | Capturing creatures with items | Capcom |
| ARK Survival Evolved | August 2015 | Taming creatures with thrown items | Studio Wildcard |
| Pokemon GO | July 2016 | Throwing Pokeballs to capture | Niantic/Nintendo |
| Craftopia | September 2020 | Pal Sphere creature capturing | Pocketpair |
| Nintendo Priority Date | December 2021 | Patent application filed | N/A |
What the Patent Actually Described
According to machine translations of the application, Nintendo attempted to patent mechanics where the game causes a computer to determine whether a capture succeeds when a thrown capture item hits a field character. If successful, the computer sets that character to be owned by the player. The application also described using similar mechanics to restrict character movement or trigger various other effects.
These descriptions essentially cover the basic loop of every creature-catching game ever made. Throw item at creature, computer calculates success based on various factors, creature becomes owned if successful. The fact that Nintendo thought this extremely broad mechanic qualified as a patentable invention in 2024 demonstrates either remarkable audacity or a fundamental misunderstanding of how established this gameplay pattern has become.
Community Reaction and Analysis
The gaming community erupted with vindication once news of the rejection spread. Reddit discussions highlighted how the Japan Patent Office essentially confirmed what many players argued from the beginning – that Palworld’s mechanics more closely resemble ARK Survival Evolved than Pokemon in most respects. One highly upvoted comment noted the irony that Nintendo would need to sue ARK developer Studio Wildcard before they could legitimately target Pocketpair for similar mechanics.
Legal experts pointed out the significance of selective enforcement in patent disputes. Large companies often wield patents against smaller competitors they can bankrupt through legal fees, while ignoring similar infringement by bigger companies with resources to mount expensive defenses. Nintendo going after indie developer Pocketpair while Epic Games, Studio Wildcard, and other major studios use similar mechanics without consequence exemplifies this pattern.
The fact that multiple games use purchased and stock assets from sources like the Unreal Marketplace further complicates Nintendo’s claims. If creature-capturing mechanics are so uniquely Nintendo’s invention, why do asset stores sell ready-made systems implementing identical functionality? The widespread availability of these gameplay templates across the industry undermines any argument that Nintendo invented something novel requiring patent protection.
What Happens Next
This rejection is non-final, meaning Nintendo has options for responding. They can abandon the application entirely, modify the claims to address the patent examiner’s concerns, or appeal the decision to Japan’s Intellectual Property High Court. Given Nintendo’s aggressive stance on this matter and the resources the company commands, abandonment seems unlikely despite the damaging evidence presented.
More likely, Nintendo will attempt to narrow the patent claims to something more specific that might avoid the prior art issues. However, making claims too narrow risks rendering the patent useless for enforcement purposes. If Nintendo carves out enough exceptions to satisfy the examiner, the resulting patent might not cover Palworld’s implementation anyway.
The patent prosecution process in Japan has been described as an endless loop, with multiple opportunities for applicants to revise and resubmit. Mueller notes that the patent examiner now looking at real-world games rather than just patent documents and academic articles considerably raises the stakes for Nintendo. It’s much harder to argue around specific gameplay footage and code than abstract prior art citations.
Impact on the Palworld Lawsuit
Importantly, this rejection doesn’t have direct legal impact on the ongoing Tokyo District Court case against Pocketpair. The lawsuit continues regardless, based on the two granted patents from the same family. However, the indirect implications are potentially massive for several reasons that could strengthen Pocketpair’s defense.
First, it demonstrates that at least one patent examiner reviewing these mechanics concluded they lack originality worthy of protection. That professional opinion from Japan’s official patent authority carries weight even if it technically applies to a different application. Second, the specific prior art cited – especially Craftopia and ARK – provides Pocketpair with documented examples they can reference when arguing these mechanics were industry-standard before Palworld existed.
Third, the rejection exposes potential vulnerabilities in Nintendo’s overall patent strategy. If one member of a closely related patent family fails scrutiny, judges might question whether the granted patents deserved approval in the first place. Patent offices make mistakes, and courts can invalidate problematic patents during infringement litigation. This rejection gives Pocketpair ammunition for challenging the validity of the patents actually being asserted against them.
The Bigger Picture on Game Patents
This case highlights longstanding concerns about how the patent system handles software and game mechanics. Many developers and legal experts argue that gameplay systems shouldn’t be patentable at all, as they represent abstract ideas rather than concrete inventions. The US and Japanese patent systems have struggled for decades to draw sensible boundaries around what qualifies as a patentable innovation in software.
One IP attorney quoted in industry coverage called Nintendo’s patent strategy an embarrassing failure of the patent system, noting that if Nintendo somehow wins this case, they could theoretically sue half the game industry for using similar mechanics. Nearly every adventure game with creature companions, every RPG with monster summoning, every title with rideable mounts could fall under Nintendo’s extremely broad patent claims.
The gaming industry has generally operated under an informal detente where companies don’t patent common gameplay mechanics precisely because doing so would create chaos. Imagine if the first company to patent jumping in a game could sue every subsequent platformer. That’s essentially what Nintendo is attempting with creature-catching mechanics that dozens of games implemented over multiple decades.
Pocketpair’s Defense Strategy
Pocketpair has been building its defense around exactly the prior art arguments that succeeded in this patent rejection. The developer recently pointed to examples like the Pokemon mod for Dark Souls 3 as additional prior art that could invalidate Nintendo’s claims. If players could catch creatures in an unofficial Dark Souls mod before Nintendo filed these patents, how can Nintendo claim exclusive ownership of the concept?
The fact that Pocketpair’s own earlier game Craftopia appears in the patent office’s prior art citation is particularly favorable for their defense. They can demonstrate a documented history of implementing these mechanics years before Nintendo’s priority date, making it difficult for Nintendo to argue that Pocketpair copied their patented innovations rather than continuing to use systems they developed independently.
Some speculation suggests Pocketpair themselves might be the anonymous third party who submitted the prior art to the patent office. While unconfirmed, it would make strategic sense for the company under legal attack to proactively challenge related patent applications before they get granted and potentially used in expanded litigation.
FAQs
What Nintendo patent did Japan reject?
Japan Patent Office rejected application number 2024-031879, which describes creature-capturing mechanics using thrown items. The application is part of Nintendo’s monster-capture patent family related to the Palworld lawsuit.
Why was Nintendo’s patent application rejected?
The patent examiner found the application lacked an inventive step, citing games like ARK Survival Evolved, Monster Hunter 4, Craftopia, Kantai Collection, and Pokemon GO as prior art proving these mechanics existed before Nintendo’s December 2021 priority date.
Does this rejection affect the Palworld lawsuit?
Not directly, as the lawsuit continues based on two other granted patents. However, it strengthens Pocketpair’s defense by demonstrating that related patents from the same family lack originality and providing documented prior art they can reference in court.
Can Nintendo appeal the patent rejection?
Yes, this is a non-final rejection. Nintendo can abandon the application, modify the claims to address concerns, or appeal to Japan’s Intellectual Property High Court. Given Nintendo’s resources and aggressive stance, they will likely attempt to revise and resubmit.
Who submitted the prior art that got the patent rejected?
The third-party submission was anonymous, though speculation suggests it could have come from Pocketpair itself. The submission documented multiple games implementing similar mechanics before Nintendo’s claimed invention date.
What games were cited as prior art?
The patent examiner cited ARK Survival Evolved, Monster Hunter 4, Craftopia, Kantai Collection, and Pokemon GO as games implementing creature-capturing mechanics before Nintendo’s December 2021 priority date.
Is this good news for Palworld?
Yes, while not directly affecting the current lawsuit, the rejection validates arguments that Nintendo’s patents cover standard industry mechanics rather than novel innovations. It provides Pocketpair with stronger evidence for their defense and raises questions about the granted patents’ validity.
Conclusion
The Japan Patent Office’s rejection of Nintendo’s creature-capture patent application represents a significant victory for common sense in game development. By citing ARK Survival Evolved, Monster Hunter 4, Craftopia, and even Nintendo’s own Pokemon GO as prior art, the patent examiner essentially confirmed what the gaming community has been saying since Nintendo filed suit against Pocketpair – these mechanics are industry-standard gameplay systems that no single company should be allowed to monopolize through patent law. While this non-final rejection doesn’t directly impact the ongoing Tokyo District Court litigation, it strengthens Pocketpair’s defense considerably by demonstrating that at least one government examiner agrees these aren’t novel inventions worthy of protection. The interconnected patent family structure means vulnerabilities exposed in one application could theoretically apply to the granted patents Nintendo is actively asserting in court. Whether this leads to those patents being invalidated or forces Nintendo to reconsider its aggressive legal strategy remains to be seen, but the rejection has certainly emboldened critics who view this lawsuit as a dangerous precedent that could allow major publishers to patent common gameplay mechanics and weaponize them against smaller competitors. As the patent prosecution process continues through what could be years of revisions, appeals, and legal maneuvering, one thing has become clear – Nintendo’s attempt to claim exclusive ownership of throwing balls at creatures is facing much stronger resistance than the company likely anticipated when it first filed these applications.