Sega sues Memento Mori developer, claiming patent infringement

Sega has sued a mobile game developer, claiming its games infringe on five patents.

The company has filed a lawsuit against Bank of Innovation, the Japanese studio best known for its game Memento Mori.

According to Otaku Research Institute (via GamesIndustry.biz), Sega is seeking ¥1 billion ($6.6 million) in damages, as well as an injuction to prevent Memento Mori from continuing to operate as it currently does.

The lawsuit alleges that Bank of Innovation infringed on five patents held by Sega, with the infringements taking place in Memento Mori and the now-defunct mobile game Phantom Beast Contract Cryptract.

One of the patents covers a game mechanic that “eliminates the conflicting psychologial challenges” that arise when using game items with a low drop rate (such as rare cards) by enabling players to play a game without carrying a lot of items with them at all times.

Industry consultant Dr Serkan Toto appeared to refer to the same patent on X, referring to it as “a specific system for fusing character cards of the same kind more easily”.

According to Toto, Bank of Innovation is “rather small” and ¥1 billion of damages “would significantly hurt BOI financially”.

He also suggests that, given Sega’s lawsuit follows Nintendo suing Palworld developer Pocketpair for patent infringement, this “might also signal a new trend in big Japanese studios looking for damages from smaller ones that surprisingly launch hit games”.

Responding to the lawsuit, Bank of Innovation says it doesn’t believe its game infringes on the patents, and said it intends to clarify the validity of its claims during the legal process.

It also says it will continue to make Memento Mori available, regardless of the outcome of the lawsuit, by taking any measures necessary.