I have a "horse of a different colour" as the old saying goes. When I was a teenager, I bought a horse from the Blood Reserve (natives). He had a lazy B on the right shoulder as that was an identifier for the Blood Reserve, and a 121 on the right hip signifying the native who had owned it.
So 2 brands, but only 1 previous owner. I would also guess that sometimes cattle were re-branded when sold to a different ranch/owner, though I hadn't seen any such cases in my few years around cattle, farms, and ranches as a teen.