Patent ID: 7617158

Claim:
A method for digital rights management performed in a system supporting digital rights management wherein the system supporting digital rights management includes system components comprising a device, a content issuer, and a rights issuer, the method for digital rights management comprising: a system hardware component other than the device performing: encrypting a content encryption key (CEK) using a public key associated with the device to produce an encrypted CEK; encrypting the encrypted CEK using an issuer encryption key to produce a twice encrypted CEK, wherein the issuer encryption key includes data corresponding to the content issuer; producing a rights object ciphertext by encrypting the twice encrypted CEK and integrity check information using the public key associated with the device, wherein the integrity check information is for integrity checking a rights object; providing the rights object ciphertext with the rights object to the device at a first point in time; and providing an issuer decryption key to the device at a second point in time, wherein the issuer decryption key is not device-unique, wherein the issuer decryption key is necessary for recovering the CEK from the rights object ciphertext, and the CEK is necessary for decrypting digital content associated with the content issuer, wherein the first point in time is prior to a time of commencement of digital content delivery to the device; and wherein the second point in time is coincident with the time of delivery of an initial part of digital content.