In 2000, Metallica discovered that a demo of its song "I Disappear", which was supposed to be released in combination with the , was receiving radio airplay. Tracing the source of the leak, the band found the file on the Napster peer-to-peer file-sharing network, and also found that the band's entire catalogue was freely available. Legal action was initiated against Napster; Metallica filed a lawsuit at the U.S. District Court, Central District of California, alleging that Napster violated three areas of the law: copyright infringement, unlawful use of digital audio interface device, and the Racketeer Influenced and Corrupt Organizations Act (RICO).