Since a patent license agreement is not a patent "assignment" or a patent application but is an ordinary contractual document, it is not recorded at the USPTO. It is handled under state laws unless a clear question of patent law is at issue. That said, there is no perfect place to search for patent license agreement data in the US.

However, you may try the following sources for licensing deals:

• SEC filings (such as 8-K, 10-K, 10-Q) can be useful for finding some data about a company patent license agreements. You may begin with SEC EDGAR, or LSEG Workspace.
• For information about drug out-licensing, please use Cortellis 
• You may also find aggregated drug licensing data via Bloomberg.  In Bloomberg, do the following: Type BI PHRMG -> Health care ->  Large pharma -> Licensing deal. 
• In 2020, USPTO launched a IP Marketplace with an initial focus on COVID-19.  It is provides a list of patent documents available to license although it did not reached the critical mass of sellers and buyers needed to make it a real option for building a market place for patent assets. Tip: you may conduct a quick Google search on patent marketplace to identify other similar and reputable platforms.

For further help, please contact infoservices@hbs.edu