Why The Grokster Case Matters

For years, the music and film industries have fought a Sisyphean battle against piracy. Companies estimate that online thieves download 2.6 billion illegal music files and some 12 million movies every month, costing them millions of dollars a year. On Dec. 10 the media bigs landed a rare win: The U.S. Supreme Court agreed to review a lower court's decision against the studios in Metro-Goldwyn-Mayer Studios Inc. (MGM ) v. Grokster Ltd. The studio's complaint has a high-profile list of backers, from the Dixie Chicks to Major League Baseball to the attorneys general of 41 states. If the court overturns the ruling, it could shift an unsteady balance between technology and creativity that has nurtured two decades of innovation in consumer electronics. The key issues:

What do the studios want?