United States Patents and Trademark Office USPTO is the Federal agency for granting U.S. patents and registering trademarks. It provides searchable databases for both patents and trademarks.
Google Patents Read and download millions of patents and patent applications using Google Patent Search.
Patents Online Vernon Kisling's guide to finding patents.
Patents and Trademarks Ran Raider's guide to researching patents and trademark. Wright State University Libraries.
esp@cenet - European Patemt Office Worldwide patent database managed by the European Patent Office
