bitcoin.org is owned by bitcoin developers.
bitcoin.com is owned by person/people who provide bitcoin services.
But who owns the "Bitcoin" brand?
If the man/entity named Satoshi Nakamoto who is widely believed to have created Bitcoin as a pioneer crypto isn't revealing himself, I believe knowing who has a trademark ownership of the Bitcoin Brand shouldn't be a concern. Anyone can freely use it and it is backed up by law. There's nothing illegal using that brand name. There isn't any copyrights infringement on it.