BHA Holdings own BHA Ltd (the football club) and The Community Stadium Ltd which owns the Amex, Training Ground and Monks Farm development. So separate companies but owned by the same company.
Whilst it wasn’t sold to them the Amex is owned by another company that rents it to the football club, both companies owned by BHA holdings. I’m sure there is a good reason for this but I don’t know what it is. It does mean we could never do what Chelsea have done however.