If doing it above board wouldn't make sense anyway, that means the idea is to do something illegal. You'd know who controls the board, how many shares the person currently buying it has secured, which way votes are going to go before they happen, etc. The rest of the shareholders, the rest of the whole market, wouldn't. You'd claim (and would probably have to in sworn testimony) that billion dollar gifts to you from Elon Musk, including your stock itself, were incidental.