If you had done some dd you would have found this is quite common and that Peter sells a number of shares and then uses the money to exercise his options to buy more shares. Get used to it. You may want to read over last years press releases to find out how many shares he had sold. You can also check the dates and look at price charts for those periods to see the market reaction and prices. 

Any shareholder is free to buy and sell whenever they please, but Peter has to make public any and all his moves. The company won't likely use the buy back to purchase these same shares.