The present invention advantageously provides a rights management system. In one embodiment, a specification of a general level of rights owned by a first intellectual property rights owner is received. A query is received for a lower level right that is a descendent of at least one of the general level...http://www.google.com.tw/patents/US7092953?utm_source=gb-gplus-share專利 US7092953 - Apparatus and methods for intellectual property database navigation
