And they come in a variety of bindingness. I didn’t notice any details in this link which makes me think this is mostly a handshake deal, but it wouldn’t be at all unusual for there to be some auditing mechanisms on a quarterly/yearly cycle.

For example, Wikimedia just recently claimed that they can’t chase some political project that critics wanted them to because most of their funds are earmarked-for/invested-in specific projects. So it does happen with US-based tech non-profits to at least some extent.