On Monday morning, the Supreme Court ruled that peer-to-peer companies could be held liable for the widespread copyright infringement of their users. It's bad news for file-swapping services and, maybe, for the broader technology industry. More Details of the case.

Internet file-sharing services will be held responsible if they intend for their customers to use software primarily to swap songs and movies illegally, the Supreme Court ruled Monday, rejecting warnings that the lawsuits will stunt growth of cool tech gadgets such as the next iPod.

At issue was whether the file-sharing services should be held liable even if they have no direct control over what millions of online users are doing with the software they provide for free. As much as 90 percent of songs and movies copied on the file-sharing networks are downloaded illegally, according to music industry filings.

The entertainment industry said it needed protection against the billions of dollars in revenue they lose to illegal swapping. Consumer groups worried that expanded liability will stifle the technology revolution of the last two decades that brought video cassette recorders, MP3 players and Apple's iPod.

Companies will have to pay music and movie artists for up to billions in losses if they are found to have promoted illegal downloading.

Two lower courts previously sided with Grokster without holding a trial. They each based their decisions on the 1984 Supreme Court ruling that Sony Corp could not be sued over consumers who used its VCRs to make illegal copies of movies.

The lower courts reasoned that, like VCRs, the file-sharing software can be used for "substantial" legal purposes, such as giving away free songs, free software or government documents. They also said the file-sharing services were not legally responsible because they don't have central servers pointing users to copyright material.

But in Monday's ruling, lower courts could find the file-sharing services responsible by examining factors such as how companies marketed the product or whether they took easily available steps to reduce infringing uses.