Capcom has filed an interesting lawsuit.

The Japanese company is suing fellow gaming publisher Koei Tecmo for infringing on a 2002 Capcom copyright for software that unlocks new content in existing games. Basically, we’re talking about disc-based expansion packs. This is all according to Siliconera, who got this info from a Japanese report by Sankei. Capcom is suing for about 980 million yen, or about $9.4 million.

The lawsuit specifically brings up Koei Tecmo’s Samurai Warriors: Xtreme Legends, which came out for the PlayStation 2 back in 2004. The disc unlocked new content for Samurai Warriors. Capcom also mentions 49 other games that it claims violate its copyright.

However, the idea of disc-based expansions is hardly new in the gaming world. Classic PC games like StarCraft and Diablo have used expansion packs to add content to old titles since the ’90s. Even the Sega Genesis used cartridges for a similar function, with Sonic and Knuckles able to connect to older Sonic games to add new levels and characters.

Capcom has been in a financial rut for a bit now. Gamers best know the developer and publisher for franchises like Mega Man, Street Fighter, and Resident Evil, but it has struggled to remain relevant in the modern gaming landscape while rumors of buyouts constantly swirl around the company.