How do I know if I'm allowed to upload a score?

Hi,
I've read several times that MuseScore has license agreements for many songs, for example here: https://musescore.com/licensing
Quote: "there are about 5 million songs to which you can upload scores without any fear that they will be blocked or deleted"
Great, but how can I find out if I'm allowed to upload a specific score? Shouldn't there be a list of licensed scores or some guidance when uploading scores?
Thanks :-)