The Motion Picture Association of America (MPAA), along with 19 other organizations representing creative artists, have asked a US Court of Appeals to uphold a lower court ruling that would effectively shut down music file-sharing service Napster. In a friend of the court brief submitted Friday, the groups lambast Napster for building a business that they say "relies on the theft of copyrighted materials," according to an MPAA statement issued Friday. The brief comes just hours before the Recording Industry Association of America (RIAA) is expected to file its own brief in its ongoing legal battle with Napster. In its lawsuit filed in December 1999 in US District Court, Northern District of California, the RIAA accused Napster's service of contributing to massive copyright violation of its members' material. Finding in favor of the RIAA, the District Court on July 26 issued a preliminary injunction requiring Napster to prevent its users from trading copyrighted music on its site. Napster appealed the order, saying that such a measure was technically infeasible and would effectively close the company down. A few days later, the Ninth Circuit US Court of Appeals granted Napster a reprieve by staying the injunction pending an appeal. In its brief filed today, the MPAA was joined by such diverse groups as the Software & Information Industry Association, The American Film Marketing Association, the Producers Guild of America, the American Federation of Television and Radio Artists, and even the National Basketball Association. They urged the appeals court to uphold the lower court's decision. "The groups filing this brief today represent the backbone of America's creative community. With one voice, we band together to send a simple and clear message: It is wrong to build a business that relies on the theft of copyrighted materials, and we oppose Napster's business model for doing just that," Jack Valenti, President and Chief Executive Officer of the Motion Picture Association of America, said in the MPAA's statement. "We call on the court to recognize that America's creative communities must be able to protect their artistic works against theft," he continued. "For if they cannot, who will invest enormous sums of money to make the next movie? Who will back the singers, songwriters, authors, photographers, developers, and artists?" Just two weeks ago, a broad coalition of IT and consumer electronics companies, including the Consumer Electronics Association, submitted a friend of the court brief of their own, in which they condemned the lower court for its ruling against Napster. They criticized federal Judge Marilyn Hall Patel for misapplying copyright law and threatening the future development of information sharing services. A copy of the MPAA's amicus brief is available on the MPAA Web site.