Nintendo and 54 game software makers on Tuesday filed a lawsuit against distributors of devices that allow unauthorized copies of games to be played on the DS portable game console. The lawsuit, filed with the Tokyo District Court, seeks an injunction on the importation and sale of R4 Revolution For DS and similar products by five foreign-affiliated firms operating in Tokyo.

Known as "majicon," the devices are essentially adapters that connect to the DS, enabling memory cards containing pirated games to be loaded.

Besides Nintendo, plaintiffs include Capcom Co. and Square Enix Co..

Nintendo has also taken legal action in South Korea, obtaining a court order in July that blocks importing emulation devices into the country.