Rhapsody was the first streaming on-demand music subscription service to offer unlimited access to a large library of digital music for a flat monthly fee, a concept advocated by business theories such as the Open Music Model. At launch, Rhapsody's library was formed of content mostly from Naxos Records and several independent labels. Over the next several months of 2002, they secured licenses from EMI, BMG, Warner Bros. Records, and Sony to add their music to the service. In July 2002, Rhapsody added Universal Records to their catalog, signing the last of the five major record labels of the time.