Tim Cook, CEO of $Apple (AAPL.US)$ , just sold 13% of his sh...

Tim Cook, CEO of $Apple(AAPL.US)$ , just sold 13% of his shares.
Usually when CEOs / Founders do large sell-offs, it's right before a major dump in global markets.
I get the feeling that we're going to see a lot more CEOs doing this sort of move in the coming days...