Hello OpenAlex!
Reading through the docs and comparing with the ROR docs I noticed that one type of institution is missing: funder.
Comparison
OpenAlex docs for the institution object and its types lists
Possible values are: Education, Healthcare, Company, Archive, Nonprofit, Government, Facility, and Other
while the linked ROR types consist of
Allowed types are education, funder, healthcare, company, archive, nonprofit, government, facility, and other.
--> In OpenAlex docs the type "funder" is missing