The suit, filed Friday in U.S. District Court for the Eastern District of Missouri, claims that ISP Internet Gateway and company founder Tim Jung violated copyrights held by Blizzard Entertainment, a Vivendi subsidiary.
The charges center on "bnetd," free software Jung helped develop and distribute to allow individuals to run servers for hosting online versions of popular Blizzard games such as "Diablo II" and "StarCraft." Blizzard runs its own online service, Battle.net, for those games, but many people have claimed the service is erratic, buggy, and riddled with players who cheat.
Vivendiin February that Internet Gateway stop offering the bnetd software, saying the program violated the company's rights under the Digital Millennium Copyright Act (DMCA). The suit makes no mention of the DMCA, instead relying on the 57-year-old Lanham Act, one of the bulwarks of U.S. copyright law.
A Blizzard representative did not immediately respond to requests for comment.
The suit alleges that the bnetd name infringes on the Battle.net trademark and accuses bnetd creators of illegally copying portions of the code for Blizzard software to create the tool.
Fred Von Lohmann, senior staff attorney for the Electronic Frontier Foundation, which is representing Internet Gateway, said the bnetd creators had no special access to Blizzard code. Instead, they simply monitored data activity while using the Battle.net service to gain a rough idea of how online play worked for the games.
"Our developers have not gotten their hands on Battle.net software," he said. "All they did was watch some packet traffic between a server and games."
The suit also alleges that by providing a means of online play that does not verify the player is using a legitimate copy of the game, bnetd is encouraging piracy.
Von Lohmann called that a spurious argument, similar to the tactics record companies have used against music-swapping service Napster. "If you've got a problem with pirates, go find some pirates and sue them," he said. "Instead, the copyright holders are going after innocent tool makers."
The suit seeks an injunction against Internet Gateway to prevent distribution of bnetd and unspecified monetary damages.