United States Patent and Trademark Office
USPTO Patent Public Search System
Search full text patents and applications
How to Conduct a Preliminary U.S. Patent Search
A Step-by-Step Strategy. (36 min. video tutorial)
Patent Center
Check the status and view associated documents for patent applications. Patent Center provides limited access to patent application information and documents. Private access provides secure, authorized access to patent application information and documents for registered customers.
Trademark Electronic Search System (TESS)
TESS provides access to the same text and image database of trademarks as currently provided to examining attorneys at the USPTO.
Trademark Electronic Application System Tutorial (TEAS)
USPTO Trademark Status and Document Retrieval system (TSDR)
Retrieves status information and overall prosecution histories for pending and registered trademarks simply by entering a valid trademark serial number or registration number.
Trademark Information Network (TMIN)
News broadcast-style videos that cover important topics and critical application filing tips for trademarks.
Commercial Patent Search Sites
Pat2Pdf
U.S. patents documents and applications converted to Adobe Acrobat files (pdf).
Espacenet
Free access to more than 70 million patent documents worldwide, containing information about inventions and technical developments from 1836 to today.
International Intellectual Property Offices
European Patent Office (EPO)
Deutsche Patent- und Markenamt (German Patent and Trademark Office)
Japan Patent Office (JPO)
Korean Intellectual Property Office (KIPO)
China National Intellectual Property Administration (CNIPA)
World Intellectual Property Organization (WIPO)
African Regional Industrial Property Organization (ARIPO) - English-speaking Africa
Organisation Africaine de la Propriété Intellectuelle (OAPI) - French-speaking Africa