Madster was one of the many P2P file sharing services that appeared in Napster's wake. Initially called AIMster, later renamed to Madster due to complain from AOL's AIM. AIMster allowed users to share their files with others, but only with those on their buddy lists. Aimster did not use the AOL/AIM network for any of its traffic, instead using its own servers. The service could import buddy lists from several instant messaging services. In December, 2004, the company was shut down by court's order after a preliminary injunction was granted. Litigation is ongoing to decide the issue of whether there is contributory or vicarious copyright infringement .