Im pretty sure he still owns the coins. No one would know he owns those coins, because no one knows who he is in real life, therefore there's nothing to worry about that, he could go on being a multimillionaire anonymously.
Nah, the pumpkin is right... As soon as a single satoshi (no pun intended) of those coins move, we knew that Satoshi was still in control over all those coins. That someone could, in the blink of an eye, move thousands upon thousands of coins. That would move the market.