Core Resources
Lens.org
Full-text of 7 million patent documents from US, Europe, Australia, WIPO, and counterparts in up to 60 countries.
U.S. Patents and Patent Applications -- Full-Text Images (1790 to date)
-Free AlternaTIFF Viewer for Images
European Patent Office -- esp@cenet.com
Dates of coverage vary by country
Free Patents Online
Download patents from the U.S. and the World Intellectual Property Organization (WIPO)in pdf or TIFF formats.
Patents and Other Links (from the British Library)
Gateway to a wealth of patent information on the web, concentrating on world-wide sources compiled by the British Lending Library -- databases, tutorials, associations, publications, manuals, document suppliers and many others!