A method and apparatus for digital content license management is disclosed that provides one or more license management devices that manage licenses for playback of digital content. The license management devices create licenses having an associated cardinality that determines the number of playback devices that can be authorized by the license. The license is stored in a set of playback devices, where the number of playback devices in the set corresponds to the cardinality of the license. The license is also included in digital content that the license authorizes for playback. Playback devices that have a license that matches a license included in the digital content are authorized to play the digital content. A single license can be used to provide authorization to play digital content from multiple sources and/or multiple types of content. Playback devices can store multiple licenses, which allows playback devices to belong to multiple sets of playback devices authorized to playback various digital content. In one embodiment digital content files can contain multiple licenses to allow the content files to be shared by multiple sets of playback devices.