These types of companies don't buy back, lol. They may PR that they are, but they don't. And retirement, what are they going to retire? They have issued most of the OS. They can't retire them, they're issued. Buy backs on billions of OS pinkies makes no sense. That's why it doesn't happen. These pinkies could care less about this share structure, which is why the structure is the way it is. He's unaffected with his preferred shares. A SS change will more than likely be an RS. Quick, easy, and cheap.