Nintendo of Japan, along with 54 other companies, has filed a lawsuit against a number of distributors that import the popular “R4 Revolution” single-slot flash cart. If you’re not aware, the device — coupled with a MicroSD card — allows users to load unsigned code onto their Nintendo DS, in addition to unauthorized copies of DS titles — otherwise referred to as ROM images.

Nintendo says the R4 cart is causing “immense monetary harm” to software companies, obviously due to its ability to run copied ROM images.

Capcom, Square Enix, Namco Bandai, SEGA, and Altus are just a few of the companies standing behind Nintendo in the suit, which has been filed in the Tokyo District Court under the Unfair Competition Prevention Law.

R4 DS [Nintendo]

Read more: R4 Ruled As Illegal In Japan, Square Enix Files Lawsuit Over Unlicensed Sword Replicas, Eidos Retains Brand Independence In Square Enix Deal, February NPD: PS3 Outsells Xbox 360, Nintendo Tops Charts, Tales of Hearts, The Most Expensive DS Title Yet?