X0202 4 2005-05-10 0 0000732485 GENZYME CORP GENZ 0001021038 TERMEER HENRI A GENZYME CORPORATION 500 KENDALL STREET CAMBRIDGE MA 02142 1 1 0 0 Chmn, President and CEO Genzyme common stock (GENZ) 2005-05-10 4 M 0 113640 14.00 A 760555 D Genzyme common stock (GENZ) 2005-05-10 4 S 0 113640 64.06 D 646915 D Genzyme common stock (GENZ) 16966 I By 401(k) Genzyme common stock (GENZ) 2371 I By Spouse Genzyme common stock (GENZ) 1256 I By Trust Genzyme NQ stock option (right to buy) 14.00 2005-05-10 4 M 0 113640 0 D 1999-05-26 2005-12-15 Genzyme common stock (GENZ) 113640 0 D The exercise of this stock option included a distribution of an additional 28 shares of Genzyme common stock. These stock options were entitled to receive a distribution of shares of Tissue Repair common stock that was paid on July 22, 1997 to Genzyme stockholders at a rate of 0.015. In connection with the formation of Genzyme Biosurgery in December 2000, shares of Genzyme Tissue Repair were converted into shares of Genzyme Biosurgery at a rate of 0.3352. In connection with the exchange of Genzyme Biosurgery stock into Genzyme stock on June 30, 2003, distributions of the Genzyme Biosurgery stock are exchanged into Genzyme stock at a rate of 0.04945. Options vested on 5/26/99 under acceleration discretion of the Compensation Committee, based on meeting certain stock price performance criteria. By: Susan P. Cogswell, Attorney-in-Fact 2005-05-12