CAMBRIDGE, Mass.--(BUSINESS WIRE)--Dyax Corp. (NASDAQ: DYAX) announced today that Jefferies & Company, Inc. exercised in full its over-allotment option to purchase an additional 2,550,000 shares of the Company’s common stock at a public offering price of $3.25 per share. The over-allotment option was granted to the underwriters by Dyax in connection with its recent offering of common stock. The exercise of the option brings the aggregate net proceeds from the offering to approximately $59.6 million. The sale of the additional shares closed on April 5, 2010.