Court chains Aimster's melodies

A U.S. District Court judge has agreed to the terms of a preliminary injunction outlined by the recording industry to halt the swapping of music files on Aimster.

The decision, announced Thursday, marked another legal victory for the Recording Industry Association of America (RIAA). The industry group has been waging a relentless battle against online person-to-person file-sharing networks--most notably Napster--that allow people to download copyrighted songs for free.

The order from Judge Marvin Aspen of the U.S. District Court in the Northern District of Illinois will force Aimster--also known as Madster--to implement technologies to prevent people from uploading or downloading copyrighted works. If it is unable to meet the terms, Aimster will be forced to shut down.

The order also requires Aimster to keep the court informed of its progress in these efforts.

"This is another clear-cut legal victory for copyright owners and everyone who wants to see the legitimate online market grow," RIAA President Cary Sherman said in a statement.

In September, the judge decided to impose an injunction on Aimster. Both parties were asked to file proposals for the terms of the injunction, but the judge only received terms from the RIAA, according to an RIAA representative. Thursday's ruling is considered the acceptance of the RIAA's proposal.

While the ruling adds another notch in the RIAA's campaign against file-swapping services, it by no means defeats the practice. As services shut down, people have migrated to alternatives such as Kazaa, StreamCast Networks' Morpheus and Grokster. The RIAA, however, also has pending lawsuits against these services.