They were forced by the new tax rules to cash in some stock based upon the vesting date. Unless you have the cash on hand, taxes are due on the stock value on the date they become fully vested. In some cases these guys may have millions of shares to pay taxes upon. In some ways they would have been better off to become fully vested at a lower price and then see the stock rise. Now they have a big problem it the stock falls as they paid taxes on the high.
