Patent Offices (classified by country)
United States : All you ever wanted to know about US Patents and more…
PCT/WIPO: WIPO’s portal on patents and the international patent system.
Patent Searches
Canada: This database lets you access over 75 years of patent descriptions and images. You can search, retrieve and study more than 1,500,000 patent documents.
United States: Search amongst all issued US Patents and all published Patent Applications. You can obtain free copies of them (page per page).
Delphion : Commercial patent search site.
Google Patents : Search and download millions of US patents and US patent applications in PDF format using Google Patent Search.
Fresh Patents : FREE patent keyword monitoring.
Europe – EspaceNet : Excellent European patent search site. Acces to patent documents from around the world.
Japan: Search in the Patent Abstracts of Japan using English keywords.
United Kingdom : Enter either the publication number or the application number in the form, then click either the Full Details button for a complete status history or the Current Details button for current status. Other Patent information is available from espacenet
PCT – Patent Searches : The PCT Online File Inspection System allows you to search more than 1 million international patent applications and to view the latest information and documents available to the International Bureau.
Guides
US Patent Term Calculation : In response to patent owner and public inquiry, the USPTO is providing a downloadable patent term calculator (beta version) as a resource to help the public estimate the expiration date of a patent. The calculator can be used to estimate the expiration dates of utility, plant, or design patents. The calculator contains prompts to enter specific information related to the patent in order to help in estimating expiration dates.
Canada – Guide to Canadian Patents : The guide is designed to be your introduction to patents and patenting procedures, and to outline how you can use the resources of the Patent Office to further your business or research venture.
Groklaw : Excellent site providing information and links to other patent related resources.
US Patent articles : A series of good articles on the US Patent system and laws.
USA – Chain of Titles : Search the chain of title records.
USA – Free Patents Online : Provides fast, easy-to-use Free access to millions of patents and patent applications in .tiff or .pdf formats.
USA – Guide to Filing A Non-Provisional (Utility) Patent Application : The purpose of this guide is to provide you with basic information about filing a utility patent application. A patent application is a complex legal document, best prepared by one trained to prepare such documents.
USA – Patents and How to Get One Book : Very good low cost book published by the U.S. Department of Commerce.
USA – Patently-O: Patent Law Blog : Excellent U.S. Patent Blog.
USA – Check Status of Patent Application : You can verify the status of any published application and of all granted Patents. It is also possible to obtain a free copy of the file wrapper of more recently filed patent applications.
WikiPatents : The WikiPatents Community contributes to the US patent system by reviewing issued patents and pending patent applications.
Others
Weird Patents : Not all Patents are created equal!
BustPatents.com : Legal resources and tools for surviving the patenting frenzy of the Internet, bioinformatics, and electronic commerce.