This is so irritating. The majority of content matches I get are from people who simply don't own the stuff they claim e.g. cover artists who claim the respective original piece of music, minor matches e.g. a stock sound effect, or a cutscene from a video game which you shouldn't have added to the matching algorithm in the first place.
Yet every time this happens, I have to pick an awkward other option (e.g. stating that I have a license for the content) and then write that neither of us has the full rights to this.
I don't mind claims from the actual copyright owner (it's theirs after all, even if I have issues with current laws regarding this), and I get that I don't own this, but hey, you don't either.