Maxygen Announces $10 Million Stock Repurchase Program

Maxygen, Inc.

today announced a stock repurchase program under which the company may purchase up to $10.0 million of its common stock through December 31, 2011. Since December 2009, Maxygen has repurchased approximately 10.0 million shares of its common stock at an aggregate cost of approximately $54.1 million. Maxygen may repurchase its common stock from time to time, in amounts, at prices and at such times as it deems appropriate, all subject to market conditions and other considerations. Maxygen may make repurchases in the open market, in privately negotiated transactions, accelerated repurchase programs or in structured share repurchase programs. The program will be conducted in compliance with the SEC's Rule 10b-18 and applicable legal requirements and will be subject to market conditions and other factors. The company also expects to establish Rule 10b5-1 trading plans from time to time to effect such purchases when appropriate.