Well consider if you were making a large profit daily, like say, $3000 ave. Okay?
That's with approx. 30,000 trades daily.

With that money you could afford to buy bitcoins daily at the best prices it reached each day. It's not a cheating thing to do, really, but isn't it a conflict of interest to do that in his own exchange?

In a very short time, he could have easily acquired the 500,000 bitcoins, but would it have been completely legal?

I'm just bringing this up, because he is hiding something in relation to the account that held 500,000 bitcoins, and if it's his, and it's held legally by him and he did nothing wrong, then why not reveal that it was theirs?