US Patent 7917643 Digital information library and delivery system

Aspects of the present disclosure relate to a computer system that can transfer a digital information file to a removable media storage. The digital information file can include targeting information, which may include combined descrambling information and information identifying a mobile playback device. The mobile playback device can render the targeted digital information file if the information identifying the mobile playback device included in the targeting information corresponds to an identifier of the mobile playback device, so as to allow the mobile playback device to descramble the targeted digital information file using the descrambling information.