From the JISC Sherpa Romeo About page https://v2.sherpa.ac.uk/romeo/about.html
Sherpa Romeo is an online resource that aggregates and presents publisher and journal open access policies from around the world. Every registered publisher or journal held in Romeo is carefully reviewed and analysed by our specialist team who provide summaries of self-archiving permissions and conditions of rights given to authors on a journal-by-journal basis where possible.
The policy information provided through this service primarily aims to serve the academic research community. Since the service launched over 15 years ago, publisher policies and the open access sector have changed a lot. Open access policy can be complex and varies according to geographical location, the institution, and the various routes to open access — all of which affects how and where you can publish your research.
All of the information provided by the service is correct to the best of our knowledge but should not be relied upon for legal advice.