Freely Accessible

• Canadian Patents Database from the Canadian Intellectual Property Office (CIPO) - 75 years of patent descriptions and images. You can search, retrieve and study more than 1,500,000 patent documents.
• esp@cenet: European Patent Information - The European Patent Office provides a free database to search patent documents from all over the world from 1836 to the present. Provides resources and help for searching patents, such as an FAQ on patents in Japan, China, and Korea.
• Japan Patent Office - Use the "Reference Room" to search Japanese patents and trademarks
• World Intellectual Property Organization Patent Search - Sponsored by the United Nations, the WIPO provides services and promotes intellectual property rights.
• United States Patent and Trademark Office (USPTO) - Search granted patents and pending applications. Full-image U.S. patents are available back to 1790. Text of the patent is searchable for patents issues since 1976. Valuable search tips and patent application information can be found as well.