Gateway to Patent Searching

• USPTO
  The United States Patent and Trademark Office's Web site is a good place to begin a search or find out more information about patents and the Office's mission and activities. Search full text of patents since Jan 1, 1976. Patents issued from 1790 through 1975 are searchable only by patent number and current U.S. classifications. Full-Page images are available back to 1790. A TIFF image viewer is required.

• LexisNexis Academic
  Provides patent searching back to 1790. Text available but no diagrams. Includes some European and Japanese patents.

• Yahoo
  The patent section of Yahoo has the USPTO and IBM sites as well as other interesting sites.

• Download U.S. Patents 1790- present
• Derwent Innovations Index A component of Web Science; includes patent information from the World Intellectual Property organization.