A Los Angeles federal court moved swiftly to issue a temporary restraining order against BlueBeat. EMI, which represents The Beatles works, filed suit against the BlueBeat site on Tuesday.

BlueBeat.com was selling songs from the British band's archives for 25 cents each. By contrast, Apple's iTunes Store sells songs for about $1, but does not have The Beatles' catalog. BlueBeat had all its Beatles bases covered, offering original recordings and remastered versions of Beatles classics.

"EMI did not authorize its content to be sold or made available on BlueBeat.com," the label said earlier this week. BlueBeat insists it was selling different sound recordings that were not EMI copyrighted by using a technique called psycho-acoustic simulation.

BlueBeat's Blue-Faced Argument

"It appears BlueBeat is arguing that they are substantially altering The Beatles material, but if the copyrighted material is the source, you are still in violation of copyright," said Rob Enderle, principal analyst at the Enderle Group.

That's the perspective under U.S. copyright law. But in other parts of the world copyright law is not as strict. Enderle pointed to a case in Eastern Europe involving a Harry Potter book that was rewritten using different characters. In court, the defendant's case held up because the book was substantially altered.

"We're pretty strict in the United States with how we consider copyright. If by listening to the song you can connect it back to the copyrighted work, that would be enough to suggest that you violated the copyright," Enderle said. "We've seen musicians with pieces that were vastly different in terms of lyrics, but the beats were the same as the copyrighted work -- and they got nailed."

Battling The Beatles

This is not the first time The Beatles have taken legal issue with a music-selling company. Several years ago, Apple Corps, the guardian of The Beatles commercial interests, claimed that iTunes violated a 1991 contract that prohibited Apple from using the name "apple" or an apple logo in connection with any music distribution. The pact was reached before the birth of the commercial Internet -- but The Beatles have used an apple logo since the 1960s.

The dispute hinged on whether Apple was in the music production business or was simply selling services, which happen to include music, over the Internet. The suit marked the third face off in two decades between Apple and the music publishing firm controlled by Paul McCartney, Ringo Starr, and the widows of George Harrison and John Lennon.

In 2006, Judge Edward Mann of Britain's High Court ruled that Apple used the fruit logo in association with its iTunes Store, not with the music itself. That, he ruled, was not a breach of contract.