<?xml version="1.0"?>
<ownershipDocument>
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	<notSubjectToSection16>0</notSubjectToSection16>
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            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
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		<footnote id="F1">On June 30, 2003 all outstanding shares of Genzyme Biosurgery and Genzyme Molecular stock were exchanged for shares of Genzyme General Stock.  Genzyme Biosurgery shareholders received .04914 of a share of Genzyme General stock for each Biosurgery share and Genzyme Molecular Oncology shareholders received .05653 of a share of Genzyme General stock for each Molecular Oncology share.</footnote>
		<footnote id="F2">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.</footnote>
		<footnote id="F3">Options vest in 1/3 annual increments on the dates of the next three annual meetings of shareholders following the date of grant.</footnote>
		<footnote id="F4">Options vest in 1/3 annual increments for 3 years beginning 5/25/00.</footnote>
		<footnote id="F5">Options vest in 50%  increments on  May 31,2001 and May 31, 2002.</footnote>
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0
D
Biosurgery DOP stock option (right to buy)
11.04
2003-06-30
4
J
0
7272
0
D
2000-05-25
2009-08-26
Genzyme Biosurgery common stock (GZBX)
7272
0
D
Biosurgery DOP stock option (right to buy)
6.69
2003-06-30
4
J
0
8000
0
D
2002-05-31
2011-02-09
Genzyme Biosurgery common stock (GZBX)
8000
0
D
Biosurgery DOP stock option (right to buy)
6.26
2003-06-30
4
J
0
2000
0
D
2002-05-31
2011-05-31
Genzyme Biosurgery common stock (GZBX)
2000
0
D
Biosurgery DOP stock option (right to buy)
4.24
2003-06-30
4
J
0
18000
0
D
2005-05-30
2012-05-30
Genzyme Biosurgery common stock (GZBX)
18000
0
D
Genzyme General DOP stock option (right to buy)
286.56
2003-06-30
4
J
0
82
0
A
1994-12-16
2004-12-16
Genzyme General common stock (GENZ)
82
82
D
Genzyme General DOP stock option (right to buy)
739.13
2003-06-30
4
J
0
122
0
A
1997-05-29
2006-05-16
Genzyme General common stock (GENZ)
122
122
D
Genzyme General DOP stock option (right to buy)
124.69
2003-06-30
4
J
0
151
0
A
1997-05-18
2007-06-18
Genzyme General common stock (GENZ)
151
151
D
Genzyme General DOP stock option (right to buy)
62.35
2003-06-30
4
J
0
673
0
A
2000-05-25
2009-05-26
Genzyme General common stock (GENZ)
673
673
D
Genzyme General DOP stock option (right to buy)
126.39
2003-06-30
4
J
0
198
0
A
2000-05-26
2009-05-26
Genzyme General common stock (GENZ)
198
198
D
Genzyme General DOP stock option (right to buy)
223.26
2003-06-30
4
J
0
359
0
A
2000-05-25
2009-08-26
Genzyme General common stock (GENZ)
359
359
D
Genzyme General DOP stock option (right to buy)
135.29
2003-06-30
4
J
0
395
0
A
2001-05-31
2011-02-09
Genzyme General common stock (GENZ)
395
395
D
Genzyme General DOP stock option (right to buy)
274.32
2003-06-30
4
J
0
112
0
A
2002-05-30
2011-05-31
Genzyme General common stock (GENZ)
112
112
D
Genzyme General DOP stock option (right to buy)
126.60
2003-06-30
4
J
0
98
0
A
2002-05-31
2011-05-31
Genzyme General common stock (GENZ)
98
98
D
Genzyme General DOP stock option (right to buy)
85.75
2003-06-30
4
J
0
890
0
A
2003-05-30
2012-05-30
Genzyme General common stock (GENZ)
890
890
D
Genzyme General DOP stock option (right to buy)
41.51
2003-06-30
4
J
0
1010
0
A
2003-05-30
2012-05-30
Genzyme General common stock (GENZ)
1010
1010
D
Molecular Oncology DOP stock option (right to buy)
7.00
2003-06-30
4
J
0
2700
0
D
1997-06-18
2007-06-18
Genzyme Molecular Oncology common stock (GZMO)
2700
0
D
Molecular Oncology DOP stock option (right to buy)
3.50
2003-06-30
4
J
0
12000
0
D
2000-05-30
2009-05-26
Genzyme Molecular Oncology common stock (GZMO)
12000
0
D
Molecular Oncology DOP stock option (right to buy)
15.40
2003-06-30
4
J
0
2000
0
D
2002-05-30
2011-05-31
Genzyme Molecular Oncology common stock (GZMO)
2000
0
D
Molecular Oncology DOP stock option (right to buy)
2.33
2003-06-30
4
J
0
18000
0
D
2003-05-30
2012-05-30
Genzyme Molecular Oncology common stock (GZMO)
18000
0
D
On June 30, 2003 all outstanding shares of Genzyme Biosurgery and Genzyme Molecular stock were exchanged for shares of Genzyme General Stock.  Genzyme Biosurgery shareholders received .04914 of a share of Genzyme General stock for each Biosurgery share and Genzyme Molecular Oncology shareholders received .05653 of a share of Genzyme General stock for each Molecular Oncology share.
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 in 1/3 annual increments on the dates of the next three annual meetings of shareholders following the date of grant.
Options vest in 1/3 annual increments for 3 years beginning 5/25/00.
Options vest in 50%  increments on  May 31,2001 and May 31, 2002.
By: Susan P. Cogswell, Attorney-in-Fact
2003-07-01