US Patent 7590600 Self-contained rights management for non-volatile memory

Access rights may be managed using non-volatile memory. The charge retention characteristics in devices with non-volatile memory are used to establish time-limited rights. Time duration is calculated using the floating gate in a storage cell. First, time-limited rights are determined from a license. Second, a set of computer software selects a time-sensitive storage cell, containing the floating gate, in the non-volatile memory that approximates the required time duration in the license.