Universal Music Group is suing the operators of two video-sharing Web sites, claiming they illegally let users share music videos and other copyright material without permission.

Universal Music, the world's largest recording company, filed separate lawsuits against Grouper Networks Inc., operator of Grouper.com, and Bolt Inc., which runs Bolt.com. Sony Corp.'s Sony Pictures Entertainment acquired Grouper for $65 million in August, and Universal Music said it may add the film studio as a defendant.

Video sites have become wildly popular over the past year, drawing millions of visitors who often find clips from movies and music videos along with homemade footage from users. Just this week, Google Inc. agreed to buy one of the top such sites, YouTube, for $1.65 billion.

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Universal Music recently signed a content licensing agreement with YouTube. The recording company said it sought licensing deals with both Grouper and Bolt, but reached agreements with neither.

In lawsuits filed Monday in U.S. District Court in Los Angeles, Universal Music claimed Grouper and Bolt actively play a role in violating copyright laws by "copying, reformatting, distributing and creating" works derived from music videos and songs owned by the label.

In one example cited in the Grouper lawsuit, a search turned up several Mariah Carey videos that could be viewed and downloaded. A video for her song "Shake It Off," had been viewed more than 50,000 times, the lawsuit said.

A similar search on Bolt.com generated a list of clips featuring Mary J. Blige, including the video for "Enough Cryin," which had been viewed more than 1,000 times, the lawsuit said.

Universal Music, a unit of French telecommunications and media company Vivendi, is seeking unspecified damages derived from any profits by the defendants, or $150,000 per copyright work that was allegedly distributed on the sites without permission.

In a statement Tuesday, New York-based Bolt said it had yet to receive a copy of the lawsuit, but added that it has always complied with music companies' requests to remove any copyright video after the fact.

A call seeking comment by Sausalito-based Grouper was not immediately returned.

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