Nintendo's aggressive stance against emulation is well-documented. Recent examples include the $2.4 million settlement with Yuzu developers in March 2024, the October 2024 cessation of Ryujinx development following Nintendo's intervention, and Valve's advised against a full Steam release for Dolphin emulator in 2023 due to Nintendo's legal pressure. The high-profile 2023 case against Gary Bowser, resulting in a $14.5 million debt to Nintendo for his role in distributing piracy-enabling devices, further highlights this commitment.
Now, a Nintendo patent attorney, Koji Nishiura, has shed light on the company's strategy. Speaking at Tokyo eSports Festa 2025, Nishiura clarified that while emulators aren't inherently illegal, their use can become illegal depending on their functionality. Specifically, emulators that copy game programs or disable console security measures may infringe on copyright. This is largely based on Japan's Unfair Competition Prevention Act (UCPA), although its extraterritorial reach is limited.
Nishiura used the Nintendo DS R4 card as an example, highlighting how its ability to bypass security and run pirated games led to a successful UCPA lawsuit against its manufacturers and resellers, effectively banning its sales in 2009. He also pointed out that tools facilitating pirated software downloads within emulators, such as the 3DS "Freeshop" or Switch "Tinfoil," may also violate copyright laws. Nintendo's lawsuit against Yuzu cited one million pirated copies of The Legend of Zelda: Tears of the Kingdom, linking the emulator's Patreon revenue to this infringement.
