UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED):

December 10, 2009

GENZYME CORPORATION

(Exact name of registrant as specified in its charter)

Massachusetts		0-14680		06-1047163
(State or other jurisdiction of incorporation or organization)		(Commission file number)		(IRS employer identification number)

500 Kendall Street, Cambridge, Massachusetts 02142

(Address of Principal Executive Offices) (Zip Code)

Registrant’s telephone number, including area code:

(617) 252-7500

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01 Other Events.

On December 10, 2009, Genzyme Corporation released a letter to shareholders, which is attached as Exhibit 99.1 to this Form 8-K.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

99.1 Letter to Genzyme Corporation Shareholders dated December 10, 2009.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	GENZYME CORPORATION


Dated: December 10, 2009	By:	/s/ Thomas J. DesRosier
		Thomas J. DesRosier
		Senior Vice President, General Counsel and Chief Legal Officer