Patent ID: 7353402

Claim:
A method of publishing digital content to enable a license server to issue a digital license corresponding to the content to one or more users desiring to render the content, the method comprising: encrypting the content according to a content key CK to result in CK(content); protecting the content key CK according to a public key for the license server PU-DRM; generating rights data associated with the content; protecting the rights data according to PU-DRM; submitting the protected rights data and the protected content key CK as a rights label to the license server for signing thereby, the license server validating the rights label and, if valid, creating a digital signature based on a private key PR-DRM corresponding to PU-DRM and based at least in part on the protected rights data to result in a signed rights label SRL and returning the SRL, whereby the license server signs both the rights data and the content key CK that are protected according to PU-DRM; receiving the returned SRL and concatenating such received SRL with CK(content) to form a content package; and distributing the content package to the one or more users; receiving from a user a request for the license corresponding to the content, the request comprising the SRL as retrieved from the content package, whereby the license server verifies its own signature of the rights label in the received SRL based on PU-DRM and based at least in part on the protected rights data, accesses the protected rights data in the SRL and reviews same to determine whether the user is entitled to the license, and if so issues the license to the user, the license including CK in a protected form accessible to the user.