LOS ANGELES

Larry Richard is one of the millions to have discovered the world of YouTube, the free website that allows people to post, watch, and share video clips. When he receives a link to the site, usually via e-mail, he spends a few moments to click and watch a clip on his computer screen - sometimes a video of a friend's singing recital, other times a snippet of a foreign commercial or a monologue from late-night TV.

"It's entertaining, it's information, it's a community of people sharing things," says Mr. Richard, a marketing consultant in Santa Monica, Calif. But is it legal, given that at least some of what he's watching is copyrighted material being disseminated by individuals who clearly do not hold the copyright?

The law on this matter is murky, and likely to get murkier before it gets clearer, say experts in intellectual property law.

Several companies such as Time Warner have been threatening YouTube with copyright infringement lawsuits. Now that Internet giant Google has purchased YouTube, experts expect that the rampant disregard of copyright law shown by early YouTube users, at least, is likely to get resolved - but they caution that each successive new technology can put early users, in particular, on nebulous legal ground, especially if financial profit is involved.

"As more and more technology comes along, the legal underpinnings governing them are not becoming clearer," says Mark McCreary, a partner in the Technology and Venture Finance Group of Fox Rothschild, which handles intellectual property cases. Increasing ability to download video clips from YouTube and to watch videos on iPods and cellphones will present users with more opportunities to violate copyright - wittingly or unwittingly, he says.

Still, those who watch videos at YouTube - whether or not such content is copyrighted - are unlikely to be pursued with the same fervor with which the music industry prosecuted those who downloaded music free of charge via the file-sharing website Napster, say Mr. McCreary and other experts.

"The very big difference between today's YouTube and the music-sharing of MP3 files of several years ago is that you have to watch and you can't - absent the knowledge of advanced hackers - copy it for your own use," says David Axtell, an intellectual property specialist at the law firm Leonard, Street and Deinard in Minneapolis. "During Napster's heyday, people were making their own digital copies and using them on their own."

But concerns should be higher for those who actually submit videos for posting and watching, say Mr. Axtell and others. Because copying and distributing copyrighted material is illegal, people who post that material on YouTube without permission are more likely to be held liable.

"There certainly will be more litigation, and Google has set aside hundreds of millions in a war chest in recognition of this," says Kevin Parks, a copyright specialist with the law firm Leydig, Voit and Mayer in Chicago.

On the side of the YouTubites are those who argue that use of such copyrighted material falls into "fair use" provisions of the law.

"It's up to the courts to continually balance the rights of those who own copyrighted material with the need for society to adapt to emerging technology," says Perry Binder, assistant professor of legal studies at Georgia State University.

Copyright laws, which give exclusive legal right to a writer, editor, composer, publisher or distributor to publish, produce, sell, or distribute an artistic work are unambiguous, experts say. But how many copies of something a person may make for personal use is far more open to interpretation by judges and courts.

Mr. Binder says movie and TV industries are figuring out how to handle the more serious abuses, such as excessive downloading by casual users, profiting from the sale of a downloaded video, and having a website that links to copyrighted videos, particularly if the Web page profits from drawing traffic to the pages.

"These people should expect 'cease and desist' letters from attorneys and face the threat of a lawsuit if copyrighted material is not taken down immediately," says Binder.

For its part, YouTube directs users to common-sense "Dos and Don'ts" at its online help center. Users are asked not to send pornography, videos of dangerous or illegal acts (such as animal abuse or bombmaking), violence, and to avoid the malicious use of stereotypes.

"We ask our users to respect copyrighted material and to only upload videos they have made or obtained the rights to use," says Jenny Nielsen, marketing manager at YouTube. "Our policy prohibits inappropriate content.... Users can flag content they feel is inappropriate and once it is flagged, YouTube reviews the material and reserves the right to remove videos from the system."

Meanwhile, YouTube's power has prompted content creators to see how they can make money from the site's content that is copyrighted. Companies such as CBS and three major recording companies - Universal Music Group, Warner Music, and Sony BMG Music Entertainment - have inked deals with Google/YouTube to share revenues generated by copyrighted content on the site.

As part of an experimental "brand channel" at the site, CBS in October agreed to offer free video clips for downloading. By Thanksgiving, 300 such clips had drawn 30 million viewers. More than 35,000 have subscribed to the free channel and CBS claims its "Late Show with David Letterman" now boasts 200,000 more viewers and its "Late Late Show with Craig Ferguson" has 7 percent more viewers.

"YouTube has not only held the threats at bay, but also shown it can be a revenue boon for old media," says Chris Taylor, senior editor of Business 2.0 Magazine.