By Amy E. Feldman

PHILADELPHIA (CBS) – Did you ever wonder how YouTube could get away with having copyrighted songs posted on it? So do the owners of the songs.

Global Music Rights is a company that manages the royalty payments for some of today’s biggest musical artists like Pharrell, John Lennon, and Fleetwood Mac to name a few. It’s recently begun a war of legal nasty grams – not a lawsuit yet but a bunch of angry letters threatening a lawsuit if YouTube doesn’t take down material that features the artists represented by Global Music Rights.

For its part, YouTube has not backed down. There are a couple of reasons why.

First, it may have license agreements with Global Music’s predecessors which gives YouTube the right to use the content.

And additionally, under the law, a website on which people post copyrighted materials won’t face any monetary penalty for copyright infringement if it has a takedown procedure, if the person claiming the copyright violation can point to specific places where its content is posted illegally.

But Global Music Rights doesn’t want to have to pinpoint specific instances. It claims that YouTube has the technology to find the infringing content itself.

For now, this has been a war of words. But if Global Music throws down the gauntlet and actually files what could be a billion dollar lawsuit on behalf of the artists, no one – especially the YouTube watchers – will be happy, happy, happy if that content disappears.