YouTube has removed from its Web site nearly 30,000 videos that Japan's entertainment industry said contained copyrighted material.

The Japan Society for Rights of Authors, Composers and Publishers said in a statement issued Friday that it has asked the popular video-sharing site to put filters in place, and take other steps to ensure that unauthorized content doesn't appear on the site in the future, the Reuters news agency reported. The Tokyo-based group represents 23 media companies, including movie studios and TV networks.

The society asked for the removal of 29,549 videos, an indication of the amount of user-uploaded material on the site that is copyrighted. Most of the video is homegrown, but a significant portion either includes copyrighted songs or pictures mixed in with user-created video. Users also regularly post clips from TV shows and music videos without permission.

YouTube, which has agreed to be acquired by search-engine giant Google Inc., regularly removes videos at the request of copyright holders. Nevertheless, the amount of copyrighted material on the site has left the company open to a lawsuit, analysts say.

To prevent legal troubles, YouTube has been signing as many deals as possible with media companies. The site has agreements with Vivendi SA's Universal Music Group, Warner Music Group Corp., Sony BMG and CBS Corp.

Nevertheless, other media companies have said they are investigating possible legal actions. Those include News Corp., General Electric Co.'s NBC Universal, Time Warner Inc., and others, according to the Wall Street Journal.

In terms of number of video streams, YouTube was third in August with 688 million, or 9.9 percent of the total on the Web, according to ComScore Networks. Fox Interactive, which includes the popular MySpace.com social network, was first with 1.4 billion streams, or 20.1 percent of the market, followed by Yahoo, which had 823 million video streams, or an 11.8 percent share.