Patent Searching: Search Tips

The fastest and easiest to use free patent search sites are: 

• Google Patents - has 120 million patents from 100 countries (sample video tutorial)
• The Lens (formerly Patent Lens) (see tutorial) - has 141 million patents from 95 countries.
• EspaceNet  has 120 million patents from 100 countries.

Both of these websites have powerful search and display capabilities, with classification searching and bulk downloading of US and patents from all over the world. The Lens includes scholarly literature as well.

Search Process:

1. Search with keywords, revise your search based on results. Click title to read abstract. Repeat your search with additional keywords.
2. Click on classification numbers for even further focused results.
   (For Google Patents hover over them for classification definitions. For the Lens select "new search for IPC classification." For a visual picture, see this guide's tab on patent classifications.)
3. Download PDFs or download citations in csv or other formats.

Purdue University points to several good tutorials on patent search strategies, including a discussion of patent classification systems. 

Note about US Patent and Trademark Office (USPTO):

f you are no longer affiliated with Cornell and wish to apply for a patent, follow the application process at the USPTO. The USPTO search engine is slow, hence searching Google Patents and the Lens are preferred. 

Email us at engrref@cornell.edu with any questions.