Why doesent Tyson release all his sparring footage on DVD

There is some of it on the internet and it has an enormous amount of views. So why doesent Tyson release all of his sparring footage of himself in the eighties when he was at his best for say 50 dollars per dvd . He could have vol 1 , vol 2, vol 3 etc . He could make a lot of money. I am sure he has hundreds of hours of him sparrring on tape from 85 to 88.