Why Beatles were on Internet radio before they were on iTunes

Beatles recordings are now available on iTunes, as a result of a recent and quite newsworthy deal. But they've long been available on Internet radio stations. This is puzzling for those not versed in the intricacies of Internet music licensing law. David Oxenford of Davis Wright Tremaine unravels the puzzle in Apple iTunes Gets the Beatles - Why Internet Radio Had Them All Along. His explanation:
The answer is the statutory license under which Internet Radio operates. While there have been many disputes over the royalties that have been imposed under the statutory license created by Congress which allow non-interactive digital music companies to use sound recordings to provide music to their customers, there is no question that the license has fulfilled one of its primary functions - making sure that there is access by Internet radio operators to the entire catalog of sound recordings available in the United States.