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As usual, America’ s supreme court ended its annual term this week by delivering a clutch of controversial decisions. The one that caught the attention of businessmen, and plenty of music lovers, was a ruling concerning the rampant downloading of free music from the internet.
Nine elderly judges might have been forgiven for finding the entire subject somewhat baffling. In fact, their lengthy written decisions on the case betray an intense interest, as well as a great deal of knowledge. Moreover, they struck what looks like the best available balance under current laws between the claims of media firms, which are battling massive infringements of their copyrights, and tech firms, which are keen to keep the doors to innovation wide open.
This case is only the latest episode in a long-running battle between media and technology companies. In 1984, in a case involving Sony’ s Betamax video recorder, the Supreme Court ruled that technology firms are not liable if their users infringe copyright, provided the device is "capable of substantial non-infringing uses." For two decades, this served as a green light for innovations. Apple’ s iTunes, the legal offspring of illegal internet file-sharing, is among the happy results. But lately, things have turned against the techies. In 2000, a California court shut down Napster, a distributor of peer-to-peer (P2P) file-sharing software. It had, the court decided, failed to stop copyright violations (though the firm relaunched as a legal online-music retailer).
In its ruling this week, the court unanimously took the view that two other p2p firms, Grokster and StreamCast, could be held liable if they encourage users to infringe copy rights. The vast majority of content that is swapped using their software infringes copy rights, which media firms say eats into their sales. Although the software firms argued they should not be responsible for their customers’ actions, the court found that they could be sued if they actually encouraged the infringement, and said that there was evidence that they had done so. On the other hand, the court did not go as far as media firms demanded: they wanted virtually any new technology to be vulnerable to legal action if it allowed any copyright infringement at all.

The case of Napster demonstrates that（）

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