Website for Patent Search File

# Search Engine/Database URL
Government Organizations (Freely Available)
1 USPTO (United States Patent and Trademark Office) http://patft.uspto.gov/
2 EspaceNet (EPO; European Patent Office) http://www.epo.org/searching/free/espacenet.html
3 Japan Patents (IPDL; Industrial Property Digital Library) http://www.ipdl.inpit.go.jp/homepg_e.ipdl
4 Indian Patent Information Retrieval System (Indian Patent and Design Office) http://ipindia.nic.in/
5 PatentScope (WIPO; World Intellectual Property Organization) http://patentscope.wipo.int/search/en/search.jsf
Open Access
6 Patent Lens http://www.patentlens.net/patentlens/structured.html
7 Google Patent Database https://www.google.com/?tbm=pts
8 Free Patents Online http://www.freepatentsonline.com/search.html
9 IP.com Intellectual Property Library http://ip.com/
10 Fresh Patents http://freshpatents.com