Recommended Patent Resources
The below is from Professor Dave Zwicky's Libguide.
Google Patents
This database features Google's easy-to-use search interface, but Google's search algorithm can be inconsistent when dealing with legal-technical patent language. You can use it for doing a first pass when patentability searching, but make sure to use other resources as well.
Please read for further information or to ask for additional patent help.
Patent Lens
This free and open database of international patents has a modern search interface and offers some unique patent searching tools.
Derwent Innovations Index
This database covers international patents and rewrites the titles in easier-to-read language. Most topics go back to the 1960s. This is a subscription database for Purdue users, and not open to the general public. Derwent is recommended for researchers and students, but is not the best choice for a formal patentability search.