In-depth reporting and analytical commentary on games industry and related regulatory issues. No legal advice.

Pocketpair’s defenses against Nintendo’s patent lawsuit unpacked: ARK, Craftopia, Zelda, FF14 etc. may render asserted patents invalid

Context: This is the seventh part of our explanatory series on Nintendo v. Pocketpair (the Pokémon-Palworld patent infringement dispute). Previous parts:

  1. Why Nintendo can sue Pocketpair over patents filed AFTER Palworld’s release
  2. Japanese patent attorney: Palworld doesn’t implement “smooth switching” of riding objects as claimed by Nintendo
  3. Two of Nintendo’s three patents-in-suit against Pocketpair relate to collecting characters: let’s look at the claims
  4. Nintendo grappling with hard choice after U.S. patent office overwhelmingly rejected anti-Palworld patent application
  5. Yesterday Nintendo received a U.S. version of another anti-Palworld patent and asked the U.S. patent office for an interview to get a third patent
  6. Nintendo secures two more anti-Palworld U.S. patents, might file multi-patent U.S. lawsuit against Pocketpair in a matter of months now

What’s new: Today a patent-specialized Japanese lawyer went to the Tokyo District Court on games fray‘s behalf to access the case file. This presuambly makes it the first website to have found out what Pocketpair’s arguments are. We are summarizing them in this article to give the gamer community an idea of how the Palworld maker is defending itself. Pocketpair raises multiple non-infringement arguments (any single one of which could be sufficient on its own) against each of the three patents-in-suit and also brings multiple invalidity contentions against each patent-in-suit. The invalidity arguments are based on what other games did before, with a particular focus on ARK and on Pocketpair’s own Craftopia, but also references to Legend of Zelda, Tomb Raider and other games.

Direct impact: The two parties’ positions are known now. Nintendo says: “Here we have three patents and you infringe each of them.” Pocketpair replies: “Each of them is invalid, and even if they were valid, we wouldn’t infringe them anyway.” The court will receive further written pleadings from the parties and will then decide after a trial.

Wider ramifications: Pocketpair’s prior art references are reflective of how games are created: they typically combine elements that other games already had, either as a result of drawing inspiration or by coincidence. Most industry players and most gamers therefore do not want to see game elements monopolized through patents on game rules (as opposed to patents on true technical progress, such as superior video compression techniques that save bandwidth).

games fray is not about “everything games” — it’s only about a very few (and high-profile) legal and regulatory issues. Another website from this family, ip fray, specializes in patent litigation. When we research the select topics games fray covers at all, we go the extra mile. In this case, we sent someone to the Tokyo District Court because this is by far the most aggressive patent enforcement any game maker ever attempted against a rival, and we want to help our readers find out what’s going on.

1. List of all games we saw mentioned in Pocketpair’s February 21 invalidity contentions

On February 21, 2025, Pocketpair filed multiple “preparatory briefs” arguing that Nintendo’s patents-in-suit shouldn’t have been granted in the first place because there was prior art (meaning that there was published material, such as other patent applications, articles or games) before the relevant priority date that already covered what Nintendo claimed to have invented.

Invalidity contentions can be based on one piece of prior art if something is pretty much a copy of pre-existing material. What one sees more often, however, is that someone defending against a patent points to a combination of two or more pieces of prior art. If someone working in the field could simply have combined those two or more elements (and would have been reasonably likely to come up with the idea of combining them), then the combination is not really an invention. In the U.S., the requirement that a combination must meet a certain standard is called the nonobviousness requirement, and the Japanese term is similar to the European concept that if you combine pre-existing things, there must be an inventive step involved that leads to the combination.

The games we found at the heart of Pocketpair’s invalidity arguments include some Nintendo titles, but that is how patent law works (their own publications can be held against those who apply for patents). It’s also interesting to see a number of mods listed, which shows that mods are sometimes at the forefront of game innovation. Here’s the complete list:

In addition to games, Pocketpair also points to the Unity game engine (product website) as prior art.

2. How Pocketpair fields and combines those prior art references against Nintendo’s patents

2.1 Pocketpair’s prior art against patent #1 (JP7545191)

For an explanation of this patent, see a table in one of our previous articles on this case. In order to understand what a patent covers, it’s not the title that matters, but the claims. “The name of the game is the claim.” This patent is about capturing characters by releasing fighting characters (monsters) or capture balls.

Pocketpair argues that its own Craftopia game is the best starting point to arrive at what that patent covers. It does not say that Craftopia already did precisely the same thing, but that one just has to combine Craftopia with other prior art in order to get there. When multiple games are listed below, it always means that any single one of them would be enough to prove that a certain feature was already known before Nintendo filed the original patent applications. We explained on January 23, 2025 that the key date for Nintendo’s patents-in-suit is a December 2021 date, even if they filed the relevant applications in 2024, i.e., after Palworld). So here are alternative ways of adding any elements that may not have been in Craftopia, the game that serves as the starting point here:

  • Rune Factory 5, Titanfall 2 and Pikmin 3 Deluxe make it easy to see how a player character can perform an action to release a monster or a capture item (like a ball) and fire in a direction by releasing a button.
  • Pikmin 3 Deluxe, Far Cry 5 and Tomb Raider already showed that there can be different types of throwable objects.
  • Pocket Souls, Octopath Traveler, Monster Super League and Final Fantasy XIV made it easy to imagine that one could pick tragets on the field and then show an indication of how likely the capture operation is to succeed.
  • Generally speaking, it has been an element of the Pokémon series for more than 30 years that different capture items have different success rates.

Alternatively to Craftopia, one can also start with the Pixelmon mod for Minecraft:

  • Alternative references for one element: Craftopia, Pocket Souls and Path of Exile.
  • Alternative references for another element: Pikmin 3 Deluxe, Pokémon Legends: Arceus, Pokemon ARK, Craftopia and Dragon Quest Builders for another.

Another alternative starting point is Pokémon ARK combined with what Pocketpair describes as well-known technology at the time.

2.2 Pocketpair’s prior art against patent #2 (JP7493117)

This is another patent related to capturing characters, and we previously explained its first claim.

Pocketpair’s first invalidity argument starts with Pocket Souls. Should anything be needed in combination with Pocket Souls, Pocketpair points to Octopath Traveler, Monster Super League, Nexomon, Craftopia, Pikmin 3 Deluxe, Nukamon for Fallout or Monster Hunter 4G as options.

An alternative in validity argument starts with the Nukamon mod for Fallout, which can be alternatively combined with Craftopia, Pocket Souls or Pokémon Sword and Pokémon Shield.

2.3 Pocketpair’s prior art against patent #3 (JP7528390)

In a previous article we explained claim 1 of that patent (on the “smooth switching” of riding objects).

Pocketpair considers ARK the best starting point and argues that one doesn’t even have to combine it with other prior art references to declare that Nintendo patent invalid.

Alternatively, ArcheAge can also be a starting point, and it could be combined with ARK, The Legend of Zelda or the Unity game engine.

A third alternative approach is to start with Riders of Icarus.

2.4 Free technology defense

This is a very abstract concept and difficult to understand if one does not know patent law inside out, but it exists in patent law in different countries. For example, in Germany it’s called the Formstein defense (Wikipedia link), and its UK equivalent is the Gillette defense. What defendants do is that they argue the following: the patent can’t be infringed by what the accused embodiment does because the patent office that granted the patent would have expected the patented invention to have something that sets it apart from this. In other words, what the accused product does would not have impressed the patent office at the time it granted the patent. Again, don’t worry if this sounds confusing: it’s hardcore patent law. Every once in a while it decides a case in a defendant’s favor, but straightforward invalidity defenses are far more common.

3. Pocketpair’s non-infringement arguments

If a given patent is defeated by Pocketpair’s invalidity arguments discussed above, then it doesn’t matter whether Palworld does what such a patent describes: you can infringe an invalid patent all you want.

But if a patent survives Pocketpair’s validity challenge, Pocketpair still has to argue that it doesn’t infringe. Pocketpair filed its non-infringement arguments on January 31, 2025, three weeks prior to the invalidity contentions. Again, it has taken us quite long to get access to the record, but here we are.

Note that a patent is only infringed if each and everyone of its claim limitations is infringed. If there’s just one thing in a claim that is not infringed, the whole claim is not infringed.

3.1 Different game genres

Nintendo filed for its patents as a result of its work on Pokémon, which is a game of a different genre than Palworld.

Pokémon and Palworld have in common that there are creatures involved that you don’t find in the real world. But Pokemon is a role-playing game where players become Pokémon trainers, while Palworld is a survival and crafting game (where players gather material sand craft items to acquire capabilities).

It is not that this is a legal argument per se. The legal battle is over patent claims, not about game genres. But the conceptual difference serves to explain why some of the game mechanics differ between Pokémon and Palworld.

3.2 Non-infringement arguments concerning patent #1 (JP7545191)

Here’s claim 1 of the ‘191 patent, with a summary of Pocketpair’s non-infringement arguments in the right column:

(1) A computer whichThis is just a broad category and Pocketpair does not dispute that Palworld runs on computers (which includes video game consoles, of course).
(2)
(2.1) based on an operation input by pressing an operation button,
(2.2) causes a player character in a virtual space
(2.2.1) to take a stance to release a capture item when a first category group including a plurality of types of capture items for capturing a field character placed on a field in a virtual space is selected,
(2.2.2) and to take a stance to release the combat character when a second category group including a plurality of types of combat characters for fighting is selected,		With respect to 2.1, Pocketpair argues that the claim language means there is one operation button for this purpose (releasing a capture item or a combat character), but in Palworld this is not a common button operation: it’s about different button operations.

As for the distinction between 2.2.1 and 2.2.2, Pocketpair argues that Palworld does not clearly distinguish between combat and non-combat states. Again, it’s a survival game.

Both 2.2.1 and 2.2.2 involve a selection of a first or second category group, but there is no such selection in Palworld.
(3) and determines an aiming direction within the virtual space based on a directional input,
(4) and, based on an operation input by an operation button different from the operation button, causes a player character in the virtual space to take a stance to release the capture item when the first category group is selected, and to release the combat character when the second category group is selected,
Here, depending on whether it is about a capture item or a combat character, the player can release such item or character.
(5)
(5.1) when the capture item is selected,
(5.1.1) the player character is caused to perform an action of releasing the operation button that was pressed when causing the player character to perform the ready action,
(5.1.2) the player character is caused to perform an action of releasing the selected capture item in the aiming direction when the capture item is selected,
(5.2) and when the combat character is selected,
(5.2.1) the player character is caused to perform an action of releasing the selected combat character in the aiming direction when the capture item is released
(5.2.2) and hits the field character,		In 5.1.1, 5.1.2 and 5.2.1, the player character is caused to “perform an action” and Pocketpair says this should be interpreted as meaning that the combat character goes on to collect objects on behalf of the player charater, but the Pals don’t actually do that.
(6)
(6.1) the player character is caused to perform a capture success determination as to whether or not the capture is successful, and
(6.2)    when the capture success determination is judged to be positive, the field character that was hit by the capture item is set to a state in which it is owned by the player;
(6.3) combat character is released to a location where it can fight with the field character, a fight between the combat character and the field character is initiated on the field.

3.2 Non-infringement arguments concerning patent #2 (JP7493117)

Here’s claim 1 of the ‘117 patent, with a summary of Pocketpair’s non-infringement arguments in the right column:

(1) A game program whichThis is just the broad category of what is claimed. And obviously there is no way to argue that Palworld is not a game program.
(2)
(2.1) in a first mode,
(2.2) causes a computer of an information processing device to determine an aiming direction within a virtual space based on a first operation input which is a directional input,
(2.3) and when a second operation input is performed, causes the aiming direction to be directed toward a field character placed on a field in the virtual space and displays a first indicator,
(2.4) and based on a third operation input, causes the player character to perform an action of releasing a capture item to capture the field character in the aiming direction,
(2.5) and when the capture item hits the field character, causes a capture success determination to be made as to whether the capture is successful, and 
(2.6) when the capture success determination is judged to be positive, causes the field character hit by the capture item to be set to a state where it is owned by the player,		Here Nintendo means a first mode in which a category group containing multiple types of capture items is selected, and a second mode in which one can make a selection from multiple types of combat characters. But Palworld doesn’t do that, and that’s not just Pocketpair’s opinion: in a February 6, 2025 article, Japanese patent attorney Ryo Arashi (firm profile), who has written a few articles (in Japanese) about this dispute, believes that Nintendo wanted to obtain the ‘191 patent, for the purpose of using it against Pocketpair, because (unlike this patent here, the ‘117 patent) it does not reference different “modes.”

WIth a view to the “second operation input” (item 2.3), Pocketpair argues that the way Nintendo describes it, it must be a function that serves as a substitute for directional input, but the LT button in Palworld does not do that, so it is not used to determine an aiming direction.
(3) and the first indicator is information which indicates the ease with which the capture success determination is judged to be positive .

Nintendo is apparently also asserting a claim from this patent that refers to combat characters. In that regard, Pocketpair argues that the combat character in question does not actually engage in combat with a field character. And there is no clear distinction in Palworld between a combat and a non-combat state.

3.3 Non-infringement arguments concerning patent #3 (JP7528390)

Here’s claim 1 of the ‘390 patent, with a summary of Pocketpair’s non-infringement arguments in the right column:

(1) A game program which causes a computer of an information processing device to control a player character within a virtual space based on an operational input,
(2)
(2.1) and when
(2.1.1) one of a plurality of types of boarding characters that the player character can board
(2.1.2) is selected from the characters owned by the player character
(2.1.3) and a boarding instruction is given,		Pocketpair says the way to interpret this sequence of selecting a character (2.1.2) and giving a boarding instruction (2.1.3) is that the selected character is boarded without a need for other operation inputs. But in Palworld it is not possible to board a character without more.
(2.2)
(2.2.1) has the player character board the selected boarding character
(2.2.2) and make it mobile,
(3)
(3.1) and when
(3.1.1) a first operational input is given
(3.1.2) while the player character is in the air,
(3.2) has the player character
(3.2.1) board an airborne boarding character among the boarding characters that can move in the air
(3.2.2) and make it mobile in the air,
(4)
(4.1) and while the player character is boarding the airborne boarding character,
(4.2) moves the player character boarding the airborne character in the air based on the operational input.		Pocketpairs says that this here refers to flying characters that can be boarded. But in Palworld one can’t select such characters for the purpose of boarding them.

With respect to other types of riding objects than airborne characters, Pocketpair notes that land-use boarding charaters would be unable or have difficulty moving anywhere else than on the ground, and water-use boarding characters would have difficulties anywhere than in the water, but that does not apply to the Palworld characters Nintendo points to.

We already discussed earlier this year that the above-mentioned Japanese patent attorney expressed doubts as to whether Palworld comes with the “smooth switching of riding objects” that Nintendo’s ‘390 patent covers (January 26, 2025 games fray article).

4. Pocketpair is not a soft target

There is no question that Pocketpair and its lawyers have made a huge effort to develop many invalidity and non-infringement arguments. Again, a single such argument for a given patent is enough to be cleared with respect to that patent. But Nintendo is suing over three patents, and Pocketpair won’t want to lose over any single one of them.

Nintendo will try to overcome Pocketpair’s defenses. It will have a lot of work to do to address all those invalidity and non-infringement arguments. Plus, Nintendo may be working on a U.S. patent lawsuit as we discussed earlier this month (April 3, 2025 games fray article), given that Nintendo is studiously trying to obtain patents that it might try to use against Palworld.

We put together this article quickly after finally getting access to the documents. With more time to digest all of this, we may be in a better position to explain everything. The assumption was that a lot of gamers who became aware of that lawsuit finally want to know what Pocketpair is doing to fend off Nintendo’s patent attack. And Pocketpair is definitely doing a lot.

5. Case number, caption and lawyers

Case number: Reiwa 6 (Wa) No. 70421

Date of complaint: September 18, 2024

Plaintiffs: Nintendo and The Pokémon Company

Defendant: Pocketpair

Court: Tokyo District Court, Civil Division 40

Counsel for Nintendo: TMI‘s Shuhei Shiotsuki, Makoto Okada and 5 others.

Counsel for Pocketpair: Nishimura & Asahi‘s Iwase Hitomi, Takatoshi Monya and 11 others; together with Sugimura & Partners‘ Sugimura Kenji and/or Sugimura Koji, Fukazu Takuhiro and 4 others.