US Patent 7822876 Time based content management for disconnected devices

Systems and methods for time based management of digital content used with electronic devices lacking a connection to a common reference time keeping device are provided. Timing calibrations are used that, when applied to times measured by such disconnected electronic devices, allow the devices to calculate modified time measurements that are approximately equal to that of the reference time keeping device. The calibration time and other calibration information for the disconnected electronic devices may be stored by a digital content service and conveyed with digital content transferred from the digital content service to the disconnected electronic devices via portable data storage devices. In this manner, digital content may be consumed by a user on a plurality of disconnected electronic devices without violating license agreements associated with the digital content.