USPTO – Website and Guides – Only patents can be searched
https://www.uspto.gov/patents/search
Global Patent Searches
PQAI – Open-source AI for Patent Data Mining
WIPO PatentScope and Guides – Global patent database
https://patentscope.wipo.int/search/en/search.jsf
The Lens – lens.org – Global patent database – excellent for biotechnology inventions
Free Patents Online – simple to use and download pdf copies
Google Patents – results are not always consistent
