USPTO Patent and Citation Data

Front page data for patents issued from January 1, 1975 to December 31, 2010, including patent numbers, issue dates, application dates, application numbers, country of origin of first named inventor, first named assignee, ownership assignment category, the primary class and subclass of each patent, the number of claims, the number of forward citations to the patent (i.e. citations in subsequently issued patents), the number of backward citations to previous U.S. utility patents, and the number of citations to non-patent references.

Citations file includes citing / cited patent pairs for the 1975 to 2010 period.