Patent ID: 8776216

Claim:
A method of authorizing access to a piece of electronic content on a host computer system, the method comprising: receiving a request from a user of the host computer system to access the piece of electronic content; retrieving a license associated with the piece of electronic content, the license comprising a control object, a controller object, a protector object, and a content key object; retrieving a first control program from the control object; executing the first control program using a digital rights management engine running on the host computer system to determine whether the request is granted, including determining that a path of valid link objects exists between nodes in a first authorization graph from a first node associated with the user to a second node associated with the host computer system, wherein each link object represents a relationship between two entities in an authorization graph, wherein a link object is valid if all of one or more conditions expressed by the link object are met; and executing a second control program included in a first link object using the digital rights management engine running on the host computer system to determine whether all of the one or more conditions expressed by the first link object are satisfied, wherein the one or more conditions expressed by the first link object includes a time restriction, and wherein the first authorization graph is formed by adding the first link object to a second authorization graph.