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		<footnote id="F2">Options vest 20% on October 16, 1997 and in 20% annual increments beginning May 16, 1998.</footnote>
		<footnote id="F3">Options vest in 20% annual increments beginning on the original date of grant.</footnote>
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X0101
4
2003-06-30
0
0000732485
GENZYME CORP
GENZ
0001021029
MOSCICKI RICHARD A
0
1
0
0
Senior Vice President
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52.21
2003-06-30
4
J
0
7448
0
D
2005-06-30
2005-12-15
Genzyme Biosurgery common stock (GZBX)
7448
0
D
Biosurgery NQ stock option (right to buy)
29.46
2003-06-30
4
J
0
2207
0
D
1997-10-16
2007-10-16
Genzyme Biosurgery common stock (GZBX)
2207
0
D
Biosurgery NQ stock option (right to buy)
19.39
2003-06-30
4
J
0
1767
0
D
1998-05-28
2008-05-28
Genzyme Biosurgery common stock (GZBX)
1767
0
D
Genzyme General NQ stock option (right to buy)
0.00
2003-06-30
4
J
0
368
0
A
2005-06-30
2005-12-15
Genzyme General common stock (GENZ)
368
368
D
Genzyme General NQ stock option (right to buy)
595.76
2003-06-30
4
J
0
109
0
A
1997-10-16
2007-10-16
Genzyme General common stock (GENZ)
109
109
D
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124.69
2003-06-30
4
J
0
842
0
A
1997-10-16
2007-10-16
Genzyme General common stock (GENZ)
842
842
D
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392.12
2003-06-30
4
J
0
87
0
A
1998-05-28
2008-05-28
Genzyme General common stock (GENZ)
87
87
D
Genzyme General NQ stock option (right to buy)
124.69
2003-06-30
4
J
0
296
0
A
1998-05-28
2008-05-28
Genzyme General common stock (GENZ)
296
296
D
Molecular Oncology NQ stock option (right to buy)
7.00
2003-06-30
4
J
0
15000
0
D
1997-10-16
2007-10-16
Genzyme Molecular Oncology common stock (GZMO)
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0
D
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7.00
2003-06-30
4
J
0
5274
0
D
1998-05-28
2008-05-28
Genzyme Molecular Oncology common stock (GZMO)
5274
0
D
On June 30, 2003 in relation to the elimination of Genzyme's tracking stock structure, all stock options of Genzyme Biosurgery and Genzyme Molecular were exchanged for stock options of Genzyme General.  The exchange ratio was based on the closing prices of all three stocks on 6/30/03.  Genzyme Biosurgery options were exchanged at a rate of .04945 and Genzyme Molecular Oncology options were exchanged at a rate of .05614.
Options vest 20% on October 16, 1997 and in 20% annual increments beginning May 16, 1998.
Options vest in 20% annual increments beginning on the original date of grant.
These options have a converted exercise price of $1,055.82 per share.
By: Susan P. Cogswell, Attorney-in-Fact
2003-07-02