U. S. Patent and Trademark Office
Official source for U.S. patents and trademarks in full text from 1976 (full page images available since 1790) with links to the Library of Congress for copyright information.
Definitions, application forms and instructions, handbooks, notices, and patent attorney directory are just a few of the products provided. Includes design patents and reissued patents as well as patents currently in application process (coverage starts March 2001). Full-text searching is available.