SC TO-T

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

SCHEDULE TO
TENDER OFFER STATEMENT
UNDER SECTION 14(D)(1) OR SECTION 13(E)(1) OF THE SECURITIES EXCHANGE ACT OF 1934

SANGSTAT MEDICAL CORPORATION
(Name Of Subject Company (Issuer))

GENZYME CORPORATION
SWIFT STARBOARD CORPORATION
(Names of Filing Persons (Offerors))

COMMON STOCK, PAR VALUE $0.001 PER SHARE
(Including the Associated Preferred Stock Purchase Rights)
(Title of Class of Securities)

801003104
(CUSIP Number of Class of Securities)

Peter Wirth
Genzyme Corporation
One Kendall Square
Cambridge, MA 02139
Telephone: (617) 252-7500
(Name, address and telephone number of person authorized
to receive notices and communications on behalf of filing persons)

with copies to:

Paul Kinsella
Ropes & Gray LLP
One International Place
Boston, Massachusetts 02110
Telephone: (617) 951-7000

CALCULATION OF FILING FEE

Transaction Valuation*		Amount Of Filing Fee**
$	642,140,033	$	51,950

*

Estimated solely for purposes of calculating amount of filing fee in accordance with Rule 0-11 under the Securities Exchange Act of 1934. The transaction value is based upon the acquisition of 28,539,557 shares of common stock, par value $0.001 per share, including the associated preferred stock purchase rights (the "Common Stock"), of SangStat Medical Corporation ("SangStat") outstanding as of June 30, 2003 for the expected consideration in the tender offer of $22.50 per share. Such number of outstanding shares assumes the (1) exercise of in-the-money exercisable options to purchase an aggregate of 1,569,697 shares of Common Stock and (2) conversion of a convertible promissory note issued by SangStat into 500,773 shares of Common Stock.

**

In accordance with Exchange Act Rule 0-11, the filing fee was determined by multiplying the transaction value of $642,140,033 by 0.0000809.

o

Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number or the Form or Schedule and the date of its filing.

Amount Previously Paid:	N/A
Form or Registration No.:	N/A
Filing Party:	N/A
Date Filed:	N/A

o

Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

ý

third-party tender offer subject to Rule 14d-1.

o

issuer tender offer subject to Rule 13e-4.

o

going-private transaction subject to Rule 13e-3.

o

amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o

        This Tender Offer Statement on Schedule TO (this "Schedule TO") relates to a tender offer by Swift Starboard Corporation, a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation ("Parent"), to purchase all the outstanding shares of common stock, par value $0.001 per share, including the associated preferred stock purchase rights (the "Shares"), of SangStat Medical Corporation, a Delaware corporation (the "Company"), at a purchase price of $22.50 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase dated August 13, 2003 (the "Offer to Purchase"), and in the related Letter of Transmittal (the "Letter of Transmittal" which, together with the Offer to Purchase, as each may be amended and supplemented from time to time, constitute the "Offer"). This Schedule TO is being filed on behalf of the Purchaser and Parent.

        The information set forth in the Offer to Purchase and the Letter of Transmittal, copies of which are filed as Exhibits (a)(1) and (a)(2) hereto, respectively, is incorporated by reference in answers to Items 1 through 9 and Item 11 of this Schedule TO, and is supplemented by the information specifically provided in this Schedule TO. The Agreement and Plan of Merger, dated as of August 4, 2003, by and among Parent, the Purchaser and the Company (the "Merger Agreement"), a copy of which is filed as Exhibit (d)(1) hereto, is also incorporated in this Schedule TO by reference.

ITEM 1.    SUMMARY TERM SHEET

        The information set forth in the SUMMARY TERM SHEET of the Offer to Purchase is incorporated herein by reference.

ITEM 2.    SUBJECT COMPANY INFORMATION

        (a)   SangStat Medical Corporation, 6300 Dumbarton Circle, Fremont, CA 94555, (510) 789-4300.

        (b)   As of June 30, 2003, there were 26,469,087 shares of common stock, $0.001 par value per share, of the Company outstanding.

        (c)   The Shares are traded on the Nasdaq National Market under the symbol "SANG." The information set forth in Section 6 "Price Range of the Shares; Dividends on the Shares" of the Offer to Purchase is incorporated herein by reference.

ITEM 3.    IDENTITY AND BACKGROUND OF FILING PERSON

        (a), (b), (c)    The information set forth in Section 9 "Certain Information Concerning Genzyme and the Purchaser" and Annex I "Directors and Executive Officers of Genzyme and the Purchaser" of the Offer to Purchase is incorporated herein by reference.

ITEM 4.    TERMS OF THE TRANSACTION

        The information set forth in the SUMMARY TERM SHEET, Section 1 "Terms of the Offer," Section 2 "Procedures for Tendering Shares," Section 3 "Withdrawal Rights," Section 4 "Acceptance for Payment and Payment," Section 5 "Certain U.S. Federal Income Tax Consequences," Section 7 "Possible Effects of the Offer on the Market for the Shares; Share Quotation; Exchange Act Registration; Margin Regulations," Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat" and Section 14 "Certain Conditions of the Offer" of the Offer to Purchase is incorporated herein by reference.

ITEM 5.    PAST CONTACTS, TRANSACTIONS, NEGOTIATIONS AND AGREEMENTS

        (a)(1)    Other than the transactions described in Item 5(b) below, during the past two years neither Parent, the Purchaser nor, to the best knowledge of Parent and the Purchaser, any of the persons listed in Annex I "Directors and Executive Officers of Genzyme and the Purchaser" of the

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Offer to Purchase has entered into any transaction with the Company or any of the Company's affiliates that are not natural persons.

        (a)(2)    Other than the transactions described in Item 5(b) below, during the past two years neither Parent, the Purchaser nor, to the best knowledge of Parent and the Purchaser, any of the persons listed in Annex I "Directors and Executive Officers of Genzyme and the Purchaser" of the Offer to Purchase has entered into any transaction or series of similar transactions with any executive officer, director or affiliate of the Company that is a natural person with an aggregate value that exceeds $60,000.

        (b)    The information set forth in the INTRODUCTION, Section 8 "Certain Information Concerning SangStat," Section 9 "Certain Information Concerning Genzyme and the Purchaser," Section 11 "Contacts and Transactions with SangStat; Background of the Offer," and Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat" of the Offer to Purchase is incorporated herein by reference.

ITEM 6.    PURPOSES OF THE TRANSACTION AND PLANS OR PROPOSALS

        (a),(c)(1)-(7)    The information set forth in the INTRODUCTION, Section 7 "Possible Effects of the Offer on the Market for the Shares; Share Quotation; Exchange Act Registration; Margin Regulations," Section 11 "Contacts and Transactions with SangStat; Background of the Offer" and Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat" of the Offer to Purchase is incorporated herein by reference.

ITEM 7.    SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION

        (a), (b), (d)    The information set forth in Section 10 "Source and Amount of Funds" of the Offer to Purchase is incorporated herein by reference.

ITEM 8.    INTEREST IN SECURITIES OF THE SUBJECT COMPANY

        The information set forth in Section 9 "Certain Information Concerning Genzyme and the Purchaser" of the Offer to Purchase is incorporated herein by reference.

ITEM 9.    PERSONS/ASSETS, RETAINED, EMPLOYED, COMPENSATED OR USED

        The information set forth in Section 16 "Fees and Expenses" of the Offer to Purchase is incorporated herein by reference.

ITEM 10.    FINANCIAL STATEMENTS

        Not applicable.

ITEM 11.    ADDITIONAL INFORMATION

        (a)(1)    Except as disclosed in Items 1 through 10 above, there are no present or proposed material agreements, arrangements, understandings or relationships between (i) Parent, the Purchaser or any of their respective executive officers, directors, controlling persons or subsidiaries and (ii) the Company or any of its executive officers, directors, controlling persons or subsidiaries.

        (a)(2)-(5)    The information set forth in the INTRODUCTION, Section 7 "Possible Effects of the Offer on the Market for the Shares; Share Quotation; Exchange Act Registration; Margin Regulations" and Section 15 "Certain Legal Matters" of the Offer to Purchase is incorporated herein by reference.

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        (b)    The information set forth in the Offer to Purchase and the Letter of Transmittal, copies of which are filed as Exhibits (a)(1) and (a)(2) hereto, respectively, to the extent not otherwise incorporated herein by reference, is incorporated herein by reference.

ITEM 12.    EXHIBITS

        See Exhibit Index immediately following the signature page.

ITEM 13.    INFORMATION REQUIRED BY SCHEDULE 13E-3

        Not applicable.

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SIGNATURES

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

	GENZYME CORPORATION
Dated: August 13, 2003	By:	/s/  G. JAN VAN HEEK Name: G. Jan van Heek Title: Executive Vice President
	SWIFT STARBOARD CORPORATION
Dated: August 13, 2003	By:	/s/  G. JAN VAN HEEK Name: G. Jan van Heek Title: President

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EXHIBIT INDEX

EXHIBIT NUMBER	DOCUMENT
(a)(1)	Offer to Purchase dated August 13, 2003.
(a)(2)	Form of Letter of Transmittal.
(a)(3)	Form of Notice of Guaranteed Delivery.
(a)(4)	Form of Letter to Brokers, Dealers, Banks, Trust Companies and Other Nominees.
(a)(5)	Form of Letter to Clients for Use by Brokers, Dealers, Banks, Trust Companies and Other Nominees.
(a)(6)	Form of Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9.
(a)(7)	Joint Press Release issued by Parent and the Company on August 4, 2003 (incorporated by reference to the Schedule TO-C filed by Parent and the Purchaser with the Securities and Exchange Commission on August 4, 2003).
(a)(8)	Transcript of conference call by Parent (incorporated by reference to the Schedule TO-C filed by Parent and the Purchaser with the Securities and Exchange Commission on August 5, 2003).
(a)(9)	Slide presentation by Parent (incorporated by reference to the Schedule TO-C filed by Parent and the Purchaser with the Securities and Exchange Commission on August 11, 2003).
(a)(10)	Summary Advertisement published in the Wall Street Journal on August 13, 2003.
(a)(11)	Complaint, Rocco Pignone vs. SangStat Medical Corporation, et al., filed on August 7, 2003 in the California Superior Court, County of Alameda.
(a)(12)	Press release issued by Parent on August 13, 2003.
(b)	Amended and Restated Credit Agreement dated December 14, 2000 among Genzyme, certain subsidiaries of Genzyme, and Fleet National Bank, as Administrative Agent.
(d)(1)	Agreement and Plan of Merger dated as of August 4, 2003 among Parent, the Purchaser and the Company.
(d)(2)	Confidentiality Agreement dated June 12, 2003 between Parent and the Company.

EX-99.(A)(1)

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TABLE OF CONTENTS

Exhibit 99(a)(1)

Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(Including the Associated Preferred Stock Purchase Rights)
of
SangStat Medical Corporation
at
$22.50 Net Per Share
by
Swift Starboard Corporation
a wholly-owned subsidiary of
Genzyme Corporation

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, SEPTEMBER 10, 2003, UNLESS THE OFFER IS EXTENDED.

The Offer is being made pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated as of August 4, 2003, among Genzyme Corporation ("Genzyme"), Swift Starboard Corporation, a wholly-owned subsidiary of Genzyme (the "Purchaser"), and SangStat Medical Corporation ("SangStat"). The board of directors of SangStat has unanimously approved the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Offer and the Merger (each as defined herein); has unanimously determined that the Merger Agreement is advisable and that the terms of the Offer and the Merger are fair to, and in the best interests of, SangStat and the stockholders of SangStat; and unanimously recommends that the stockholders of SangStat accept the Offer and tender their shares of SangStat common stock, $0.001 par value per share, including all preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, between SangStat and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares"), pursuant to the Offer.

The Offer is conditioned upon, among other things, (1) there being validly tendered and not withdrawn prior to the expiration of the Offer that number of Shares that would represent more than 50% of all outstanding Shares (on a fully diluted basis), (2) the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, having expired or been terminated, (3) the applicable waiting period under Germany's Act Against Restraints of Competition having expired or been terminated, and (4) any clearances or approvals required under applicable pre-merger notification laws or regulations of other foreign jurisdictions having been obtained.

        Questions and requests for assistance may be directed to Innisfree M&A Incorporated (the "Information Agent") at its address and telephone number set forth on the back cover of this Offer to Purchase. Stockholders of SangStat may obtain additional copies of this Offer to Purchase, the Letter of Transmittal, the Notice of Guaranteed Delivery or any other tender offer materials from the Information Agent and may also contact their brokers, dealers, banks, trust companies or other nominees for copies of these documents.

The Dealer Manager for the Offer is:

August 13, 2003

IMPORTANT

        Any stockholder desiring to tender all or any portion of such stockholder's Shares must:

1.

For Shares that are registered in such stockholder's name and held as physical certificates:



•

complete and sign the Letter of Transmittal (or a manually signed facsimile) in accordance with the instructions in the Letter of Transmittal;



•

have such stockholder's signature on the Letter of Transmittal guaranteed if required by Instruction 1 to the Letter of Transmittal; and



•

mail or deliver the Letter of Transmittal (or a manually signed facsimile), the certificates for such Shares and any other required documents to American Stock Transfer & Trust Company (the "Depositary").



2.

For Shares that are registered in such stockholder's name and held in book-entry form:



•

complete and sign the Letter of Transmittal (or a manually signed facsimile) in accordance with the instructions in the Letter of Transmittal or prepare an Agent's Message (as defined herein);



•

if using the Letter of Transmittal, have such stockholder's signature on the Letter of Transmittal guaranteed if required by Instruction 1 to the Letter of Transmittal;



•

deliver an Agent's Message or the Letter of Transmittal (or a manually signed facsimile) and any other required documents to the Depositary; and



•

transfer the Shares through book-entry transfer into the Depositary's account.



3.

For Shares that are registered in the name of a broker, dealer, bank, trust company or other nominee:



•

contact the broker, dealer, bank, trust company or other nominee and request that the broker, dealer, bank, trust company or other nominee tender the Shares to the Purchaser before the expiration of the Offer.

The Letter of Transmittal, the certificates for the Shares and any other required documents must be received by the Depositary before the expiration of the Offer, unless the procedures for guaranteed delivery described in Section 2 "Procedures for Tendering Shares" of this Offer to Purchase are followed.

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TABLE OF CONTENTS

SUMMARY TERM SHEET
INTRODUCTION
THE TENDER OFFER
1.	Terms of the Offer
2.	Procedures for Tendering Shares
3.	Withdrawal Rights
4.	Acceptance for Payment and Payment
5.	Certain U.S. Federal Income Tax Consequences
6.	Price Range of the Shares; Dividends on the Shares
7.	Possible Effects of the Offer on the Market for the Shares; Share Quotation; Exchange Act Registration; Margin Regulations
8.	Certain Information Concerning SangStat
9.	Certain Information Concerning Genzyme and the Purchaser
10.	Source and Amount of Funds
11.	Contacts and Transactions with SangStat; Background of the Offer
12.	Purpose of the Offer; the Merger Agreement; Plans for SangStat
13.	Dividends and Distributions
14.	Certain Conditions of the Offer
15.	Certain Legal Matters
16.	Fees and Expenses
17.	Miscellaneous
ANNEX I—Directors and Executive Officers of Genzyme and the Purchaser
ANNEX II—Section 262 of the Delaware General Corporation Law: Rights of Appraisal

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SUMMARY TERM SHEET

Securities Sought:	All outstanding shares of common stock, including the associated preferred stock purchase rights, of SangStat Medical Corporation
Price Offered Per Share:	$22.50
Scheduled Expiration of Offer:	September 10, 2003
Purchaser:	Swift Starboard Corporation, a wholly-owned subsidiary of Genzyme Corporation
SangStat Board Recommendation:	SangStat's board of directors recommends tendering in the offer

        The following are some of the questions that you, as a stockholder of SangStat Medical Corporation, may have and answers to those questions. This summary term sheet is not complete and we urge you to read carefully the remainder of this offer to purchase, the letter of transmittal and the other documents to which we have referred because they contain additional important information.

Who is offering to buy my shares of SangStat common stock?

        Our name is Swift Starboard Corporation. We are a Delaware corporation formed for the purpose of making a tender offer for all of the outstanding common stock of SangStat Medical Corporation. We are a wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation. See the "Introduction" and Section 9 "Certain Information Concerning Genzyme and the Purchaser" of this offer to purchase.

How much are you offering to pay?

        We are offering to pay $22.50 per share in cash.

Will I have to pay any fees or commissions?

        You are responsible for paying any fees or expenses you incur in tendering your shares in the offer. For example, if you own your shares through a broker or other nominee, and your broker tenders your shares on your behalf, your broker or nominee may charge you a fee for doing so. You should consult your broker or nominee to determine whether any charges will apply. If you are the record owner of your shares and you tender your shares to us in the offer, you will not have to pay brokerage fees or similar expenses. You may be required to pay transfer taxes under certain circumstances described in the letter of transmittal. See the "Introduction" of this offer to purchase.

Do you have the financial resources to make payment?

        Genzyme, our parent company, will provide us with sufficient funds to purchase all of the outstanding shares of SangStat common stock, including the associated preferred stock purchase rights, that are validly tendered and to pay our related fees and expenses. See Section 10 "Source and Amount of Funds" of this offer to purchase.

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Is your financial condition relevant to my decision to tender in the offer?

        We do not think that our financial condition is relevant to your decision to tender your shares in the offer because:

•

we have sufficient funds available, through our parent company Genzyme, to purchase all shares validly tendered in the offer;



•

the offer is not subject to any financing condition;



•

the offer is for all of the outstanding shares of SangStat common stock and we will purchase such shares solely for cash; and



•

if we consummate the offer, we will acquire any remaining shares for the same cash price through a second-step merger.

See Section 10 "Source and Amount of Funds" of this offer to purchase.

Will the offer be followed by a second-step merger if all the shares are not tendered in the offer?

        If we accept for payment and pay for more than 50% of the outstanding shares of SangStat common stock (determined on a fully diluted basis) and the other conditions to the merger are satisfied or waived, we will merge with and into SangStat upon the vote of the SangStat stockholders, if such vote is required. If that merger takes place, Genzyme will own all of the shares of SangStat and, subject to appraisal rights under applicable law, all remaining SangStat stockholders will receive $22.50 per share in cash in the merger. There are no appraisal rights available in connection with the offer, but stockholders who have not sold their shares in the offer would have appraisal rights in connection with the merger under Delaware law if these rights are perfected. See the "Introduction" of this offer to purchase. See also Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat" of this offer to purchase for a description of the conditions to the merger and a summary of appraisal rights under Delaware law. For additional information regarding appraisal rights, you should review Annex II to this offer to purchase which contains Section 262 "Appraisal Rights" of the Delaware General Corporation Law.

If I decide not to tender, how will the offer affect my shares?

        If the second-step merger takes place, you will receive the same amount of cash per share that you would have received had you tendered your shares in the offer, subject to your right to pursue appraisal under Delaware law. Therefore, if the merger takes place and you do not perfect your appraisal rights, the only difference between tendering your shares and not tendering your shares is that you will be paid earlier if you tender your shares. However, if the merger does not take place after the offer closes, the number of stockholders and the number of shares that are still in the hands of the public may be so small that there may no longer be an active public trading market (or, possibly, any public trading market) for the shares. Also, the shares may no longer be eligible to be traded on Nasdaq or any securities exchange, and SangStat may cease making filings with the Securities and Exchange Commission, known as the SEC, or otherwise cease being required to comply with the SEC's rules relating to publicly held companies. See Section 7 "Possible Effects of the Offer on the Market for the Shares; Share Quotation; Exchange Act Registration; Margin Regulations" and Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat" of this offer to purchase.

How long do I have to tender in the offer?

        You will have until 12:00 midnight, New York City time, on Wednesday, September 10, 2003, to tender your shares in the offer, unless we extend the expiration date of the offer. If you cannot deliver everything that is required in order to make a valid tender by that time, you may be able to use a

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guaranteed delivery procedure, which is described in Section 1 "Terms of the Offer" and Section 2 "Procedures for Tendering Shares" of this offer to purchase.

Can the offer be extended?

        We may extend the offer if:

•

any of the conditions to our obligation to accept tendered shares have not been met and we have not waived such conditions before the offer has expired (see below, "What are the most significant conditions to the offer?")



•

any rule, regulation or interpretation of the SEC or its staff applicable to the offer requires that the offer be extended; or



•

sufficient shares have not been tendered upon expiration of the offer to permit a second-step merger without a meeting of SangStat stockholders. In this case, we may extend the offer for up to an additional 20 business days.

        We may also elect to provide a "subsequent offering period," which would be an additional period of three to 20 business days beginning after the offer expires. During this subsequent offering period, stockholders would be permitted to tender, but not withdraw, their shares and receive the same per share amount paid in the offer. We do not currently intend to provide a subsequent offering period, although we reserve the right to do so.

        See Section 1 "Terms of the Offer" of this offer to purchase.

How will I be notified if the offer is extended?

        If we extend the offer or provide a subsequent offering period, we will inform American Stock Transfer & Trust Company (which is the depositary for the offer) of that fact, and will make a public announcement of the extension or subsequent offering period not later than 9:00 a.m., New York City time, on the next business day following the scheduled expiration of the offer (including any extension of the offer). See Section 1 "Terms of the Offer" of this offer to purchase.

What are the most significant conditions to the offer?

        We would not be obligated to purchase any shares if:

•

we would not own more than 50% of the outstanding shares of SangStat common stock (determined on a fully diluted basis) upon accepting all shares validly tendered and not withdrawn before the offer has expired;



•

the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 has not expired or been terminated;



•

the applicable waiting period under Germany's Act Against Restraints of Competition has not expired or been terminated;



•

any clearances or approvals required under applicable pre-merger notification laws or regulations of other foreign countries have not been obtained; or



•

an event occurs that has a material adverse effect on SangStat.

The offer is also subject to a number of other conditions. See Section 14 "Certain Conditions of the Offer" of this offer to purchase.

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How do I tender my shares?

        If your shares are registered in your name and are held as physical certificates, you must:

•

complete and sign the letter of transmittal;



•

have your signature on the letter of transmittal guaranteed if required by the instructions in the letter of transmittal; and



•

mail or deliver the letter of transmittal, the certificates for your shares and any other documents required by the letter of transmittal to American Stock Transfer & Trust Company (which is the depositary for the offer).

        If your shares are registered in your name and are held in book-entry form, you must:

•

deliver an "agent's message" or a completed and signed letter of transmittal (with any required signature guarantees), and any other documents required by the letter of transmittal, to American Stock Transfer & Trust Company (which is the depositary for the offer); and



•

transfer the shares through book-entry transfer into the depositary's account.

        If your shares are held in street name (i.e., through a broker, dealer or nominee), you must contact your nominee and request that your shares be tendered in the offer.

        The Depositary must receive all of the required documents before the offer expires, unless you are able to use a guaranteed delivery procedure.

        For additional information on the procedures for tendering your shares, see Section 2 "Procedures for Tendering Shares" of this offer to purchase.

Until what time can I withdraw previously tendered shares?

        You can withdraw shares at any time before the offer expires. Also, if we have not accepted your shares for payment before October 13, 2003, you can withdraw shares at any time thereafter until we do accept your shares for payment. You will not have the right to withdraw shares tendered during any subsequent offering period, if we elect to provide one. See Section 1 "Terms of the Offer" and Section 3 "Withdrawal Rights" of this offer to purchase.

How do I withdraw previously tendered shares?

        You or your nominee must deliver a written notice of withdrawal, or a facsimile of one, with the required information to the depositary while you still have the right to withdraw the shares. See Section 1 "Terms of the Offer" and Section 3 "Withdrawal Rights" of this offer to purchase.

What does the board of directors of SangStat think of the offer?

        The board of directors of SangStat unanimously recommends that stockholders accept the offer and tender their shares of SangStat common stock in the offer. At a meeting held on August 3, 2003, the board of directors of SangStat, by unanimous vote, (1) approved the merger agreement that we, Genzyme and SangStat entered into and the transactions contemplated by the merger agreement, including the offer and the second-step merger, and (2) determined that the terms of the offer and the second-step merger are fair to, and in the best interests of, SangStat and its stockholders. See the "Introduction" to this offer to purchase.

What is the market value of my shares as of a recent date?

        On August 1, 2003, the last trading day before Genzyme and SangStat announced that they had signed the merger agreement, the last sale price of the shares reported on the Nasdaq National Market

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was $15.475 per share. On August 12, 2003, the last sale price of the shares was $22.31 per share. We advise you to obtain a recent quotation for shares of SangStat common stock in deciding whether to tender your shares. See Section 6 "Price Range of the Shares; Dividends on the Shares" of this offer to purchase.

What are the U.S. federal income tax consequences of tendering shares?

        The receipt of cash for shares pursuant to the offer will be a taxable transaction for U.S. federal income tax purposes. In general, a stockholder who sells shares pursuant to the offer will recognize gain or loss for U.S. federal income tax purposes equal to the difference, if any, between the amount of cash received and the stockholder's adjusted tax basis in the shares sold pursuant to the offer. See Section 5 "Certain U.S. Federal Income Tax Consequences."

Who should I call if I have questions about the tender offer?

        You can call Innisfree M&A Incorporated collect at (212) 750-5833 or toll-free at (888) 750-5834. Innisfree is acting as the information agent for our tender offer. See the back cover of this offer to purchase.

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To: All Holders of Common Stock of SangStat Medical Corporation

INTRODUCTION

        Swift Starboard Corporation, a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation ("Genzyme"), hereby offers to purchase all of the outstanding shares of common stock, $0.001 par value per share, including all preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, between SangStat Medical Corporation and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares"), of SangStat Medical Corporation, a Delaware corporation ("SangStat"), at a price of $22.50 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in this Offer to Purchase and in the related Letter of Transmittal (which, together with any amendments or supplements hereto or thereto, collectively constitute the "Offer").

        The Purchaser is a corporation newly formed in connection with the Offer and the transactions contemplated by the Merger Agreement (as hereinafter defined). Genzyme is a publicly-held, global biotechnology company whose shares are traded on the Nasdaq National Market ("Nasdaq") under the symbol "GENZ." For additional information about Genzyme and the Purchaser, see Section 9 "Certain Information Concerning Genzyme and the Purchaser" of this Offer to Purchase.

        Stockholders whose Shares are registered in their own names and who tender directly to the Depositary (as defined below) will not be obligated to pay brokerage fees or commissions or, except as set forth in Instruction 6 of the Letter of Transmittal, transfer taxes on the sale of Shares pursuant to the Offer. Stockholders who hold their Shares through banks or brokers should check with such institutions as to whether they charge any service fees. The Purchaser will pay all fees and expenses of American Stock Transfer & Trust Company, which is acting as the Depositary (the "Depositary"), Innisfree M&A Incorporated, which is acting as the Information Agent (the "Information Agent"), and Credit Suisse First Boston LLC ("Credit Suisse First Boston"), which is acting as the Dealer Manager (the "Dealer Manager"), incurred in connection with the Offer. See Section 16 "Fees and Expenses" of this Offer to Purchase.

        The Offer is being made pursuant to the Agreement and Plan of Merger, dated as of August 4, 2003, among Genzyme, the Purchaser and SangStat (the "Merger Agreement") pursuant to which, following the consummation of the Offer and the satisfaction or waiver of certain conditions, the Purchaser will be merged with and into SangStat, with the surviving entity becoming a wholly-owned subsidiary of Genzyme (the "Merger"). In the Merger, each outstanding Share (other than Shares owned by Genzyme, the Purchaser or SangStat, or by stockholders, if any, who are entitled to and properly exercise appraisal rights under Delaware law) will be converted into the right to receive the price per Share paid pursuant to the Offer in cash, without interest thereon. Stockholders who exercise appraisal rights under Delaware law will receive a judicially determined fair value for their Shares, which value could be more or less than the price per Share to be paid in the Merger.

        The Merger Agreement is more fully described in Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat" of this Offer to Purchase.

        The board of directors of SangStat unanimously recommends that the stockholders of SangStat accept the Offer and tender their Shares pursuant to the Offer and that the stockholders of SangStat adopt the Merger Agreement, if such adoption is required. At a meeting held on August 3, 2003, the board of directors, by a unanimous vote, (1) approved the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Offer and the Merger, and declared that the Merger Agreement is advisable and (2) determined that the terms of the Offer and the Merger are fair to, and in the best interests of, SangStat and its stockholders. The factors considered by the board of directors of SangStat in arriving at its decision to approve the Merger Agreement, the Offer and the

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Merger and to recommend that stockholders of SangStat accept the Offer and tender their Shares pursuant to the Offer are described in SangStat's Solicitation/Recommendation Statement on Schedule 14D-9 (the "Schedule 14D-9"), which has been filed with the Securities and Exchange Commission (the "SEC") and is being mailed to stockholders of SangStat with this document.

        The Offer is conditioned upon, among other things, (1) there being validly tendered and not withdrawn prior to the Expiration Date (as defined in Section 1 hereof) that number of Shares which, together with that number of Shares owned by the Purchaser, Genzyme and Genzyme's other subsidiaries, would represent more than 50% of the Fully Diluted Shares (as defined in Section 14 hereof) on the date of purchase pursuant to the Offer (the "Minimum Condition"), (2) the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act") applicable to the purchase of Shares pursuant to the Offer or to the Merger having expired or been terminated, (3) the waiting period under Germany's Act Against Restraints of Competition (the "German AARC") applicable to the purchase of Shares pursuant to the Offer or to the Merger having expired or been terminated, (4) any clearances or approvals required under applicable pre-merger notification laws or regulations of other foreign jurisdictions having been obtained and (5) there occurring no events or changes since August 4, 2003 which have had or are reasonably likely to have or constitute, individually or in the aggregate, a Material Adverse Effect (as defined in Section 12 hereof) on SangStat.

        Consummation of the Merger is subject to a number of conditions, including approval by the stockholders of SangStat, if such approval is required under applicable law, and Shares having been purchased pursuant to the Offer. In the event the Purchaser acquires 90% or more of the outstanding Shares pursuant to the Offer or otherwise, the Purchaser will be able to merge with and into SangStat pursuant to the "short-form" merger provisions of the Delaware General Corporation Law (the "DGCL"), without prior notice to, or any action by, any other stockholder of SangStat. In addition, in order to facilitate a short-form merger following the completion of the Offer, SangStat has granted the Purchaser an option to purchase up to the number of newly issued shares of SangStat common stock that represent 19.9% of the outstanding Shares for a purchase price of $22.50 per share (or the highest price paid for any Share in the Offer). This option is exercisable only if the Purchaser has acquired at least 75% but less than 90% of the outstanding Shares pursuant to the Offer. See Section 12, "Purpose of the Offer; the Merger Agreement; Plans for SangStat."

        SangStat has informed the Purchaser that, as of June 30, 2003, (1) 26,469,087 Shares were issued and outstanding, (2) a total of 2,086,920 Shares were issuable upon the exercise of vested options, (3) 50,000 Shares were issuable upon the exercise of vested warrants and (4) 500,773 Shares were issuable upon conversion of a convertible promissory note issued by SangStat (the "Convertible Note"), representing a total of 29,106,780 Fully Diluted Shares (as defined in Section 14 hereof). Based upon the foregoing, the Minimum Condition would be satisfied if at least 14,553,391 Shares are validly tendered and not withdrawn prior to the Expiration Date. The actual number of Shares required to be tendered to satisfy the Minimum Condition will depend upon the actual number of Fully Diluted Shares on the date that the Purchaser accepts Shares for payment pursuant to the Offer. If the Minimum Condition is satisfied, and the Purchaser accepts for payment Shares tendered pursuant to the Offer, the Purchaser will be able to elect at least a majority of the members of SangStat's board of directors and would have sufficient voting power to effect the Merger without the affirmative vote of any other stockholder of SangStat. See Section 12 "Purpose of the Offer; the Merger Agreement; Plans for SangStat."

        Certain U.S. federal income tax consequences of the sale of Shares pursuant to the Offer and the conversion of Shares pursuant to the Merger are described in Section 5 "Certain U.S. Federal Income Tax Consequences."

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This Offer to Purchase and the related Letter of Transmittal contain important information and you should read them carefully and in their entirety before you make any decision with respect to the Offer.

THE TENDER OFFER

1.    Terms of the Offer

        Upon the terms and subject to the conditions of the Offer, the Purchaser will accept for payment and pay $22.50 per Share, net to the seller in cash, without interest thereon, for all Shares validly tendered and not withdrawn prior to the Expiration Date. The term "Expiration Date" means 12:00 midnight, New York City time, on Wednesday, September 10, 2003, unless and until the Purchaser shall have extended the period of time during which the Offer is open in accordance with the terms of the Merger Agreement, in which event the term "Expiration Date" shall mean the latest time and date on which the Offer, as so extended by the Purchaser, expires.

        The Purchaser may, without the consent of SangStat, extend the Offer, and thereby delay acceptance for payment of, and the payment for, any Shares, by giving oral or written notice of such extension to the Depositary if:

•

any of the conditions to the Purchaser's obligation to purchase Shares are not satisfied or waived as of the Expiration Date;



•

any rule, regulation or interpretation of the SEC or its staff applicable to the Offer requires that the Offer be extended; or



•

sufficient Shares have not been validly tendered and not withdrawn pursuant to the Offer to permit the Merger to be effected without a meeting of SangStat stockholders in accordance with the DGCL. In this case, the Purchaser may extend (or re-extend) the Offer for up to a total of 20 additional business days.

        If at the Expiration Date all of the conditions to the Offer have been satisfied or waived, the Purchaser may elect to provide a subsequent offering period of three to 20 business days (a "Subsequent Offering Period") in accordance with Rule 14d-11 under the Securities and Exchange Act of 1934, as amended (the "Exchange Act"). A Subsequent Offering Period would be an additional period of time, following the expiration of the Offer, during which stockholders may tender Shares not tendered in the Offer and receive the same per share amount paid in the Offer. During a Subsequent Offering Period, the Purchaser will immediately accept and promptly pay for Shares as they are tendered and tendering stockholders will not have withdrawal rights. The Purchaser cannot elect to provide a Subsequent Offering Period unless the Purchaser announces the results of the Offer, including the approximate number and percentage of Shares deposited in the Offer, no later than 9:00 a.m., New York City time, on the next business day after the Expiration Date and immediately begins the Subsequent Offering Period. The Purchaser does not currently intend to provide a Subsequent Offering Period, although it reserves the right to do so in its sole discretion.

Under no circumstances will interest be paid on the purchase price for tendered Shares, regardless of any extension of or amendment to the Offer or any delay in paying for such Shares.

        The Purchaser may, at any time and from time to time prior to the expiration of the Offer, waive any condition to the Offer or modify the terms of the Offer, by giving oral or written notice of such waiver or modification to the Depositary, except that, without the consent of SangStat, the Purchaser shall not:

•

reduce the price per Share to be paid pursuant to the Offer;



•

change the form of consideration payable in the Offer;

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•

reduce the number of Shares subject to the Offer;



•

impose additional conditions to the Offer or amend any existing conditions of the Offer in any manner adverse to SangStat or its stockholders;



•

extend the Offer other than as described in this Section 1 of this Offer to Purchase; or



•

waive or change the Minimum Condition.

        If by 12:00 midnight, New York City time, on Wednesday, September 10, 2003 (or any date or time then set as the Expiration Date), any or all of the conditions to the Offer have not been satisfied or waived, the Purchaser, subject to the terms of the Merger Agreement and the applicable rules and regulations of the SEC, may:

•

terminate the Offer and not accept for payment or pay for any Shares and return all tendered Shares to tendering stockholders;



•

except as set forth above with respect to the Minimum Condition, waive all the unsatisfied conditions and accept for payment and pay for all Shares validly tendered and not withdrawn prior to the Expiration Date;



•

except as set forth above, extend the Offer and, subject to the right of stockholders to withdraw Shares until the Expiration Date (as extended), retain the Shares that have been tendered during the period or periods for which the Offer is extended; or



•

except as set forth above, amend the Offer.

        Any extension, waiver, amendment or termination will be followed as promptly as practicable by public announcement thereof. An announcement in the case of an extension will be made no later than 9:00 a.m., New York City time, on the next business day after the previously scheduled Expiration Date. Without limiting the manner in which the Purchaser may choose to make any public announcement, subject to applicable law (including Rules 14d-4(d) and 14d-6(c) under the Exchange Act, which require that material changes be promptly disseminated to holders of Shares), the Purchaser will have no obligation to publish, advertise or otherwise communicate any such public announcement other than by issuing a release to the PR Newswire. As used in this Offer to Purchase, "business day" has the meaning set forth in Rule 14d-1 under the Exchange Act.

        If the Purchaser makes a material change in the terms of the Offer or the information concerning the Offer or waives a material condition of the Offer, the Purchaser will disseminate additional tender offer materials and extend the Offer to the extent required by Rules 14d-4(d), 14d-6(c) and 14e-1 under the Exchange Act. The minimum period during which an offer must remain open following material changes in the terms of such offer or information concerning such offer, other than a change in price or a change in the percentage of securities sought, will depend upon the facts and circumstances then existing, including the relative materiality of the changed terms or information. With respect to a change in price or a change in the percentage of securities sought, a minimum period of 10 business days is required to allow for adequate dissemination to stockholders.

        As described above, the Purchaser may, subject to certain conditions, elect to provide a Subsequent Offering Period. In a public release, the SEC has expressed the view that the inclusion of a Subsequent Offering Period would constitute a material change to the terms of the Offer requiring the Purchaser to disseminate new information to stockholders in a manner reasonably calculated to inform them of such change sufficiently in advance of the Expiration Date (generally five business days). In the event the Purchaser elects to provide a Subsequent Offering Period, it will notify stockholders of SangStat consistent with the requirements of the SEC.

        SangStat has provided the Purchaser with SangStat's stockholder lists and security position listings for the purpose of disseminating the Offer to holders of Shares. This Offer to Purchase, the Letter of

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Transmittal and other related materials will be mailed to record holders of Shares, and will be furnished to brokers, dealers, banks, trust companies and similar persons whose names, or the names of whose nominees, appear on the stockholder lists, or, if applicable, who are listed as participants in a clearing agency's security position listing, for subsequent transmittal to beneficial owners of Shares.

2.    Procedures for Tendering Shares

        Valid Tender.    A stockholder must follow one of the following procedures to validly tender Shares pursuant to the Offer:

•

for Shares held as physical certificates, the certificates for tendered Shares, a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees and any other documents required by the Letter of Transmittal must be received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase prior to the Expiration Date;



•

for Shares held in book-entry form, either a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent's Message (as defined below), and any other required documents, must be received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase, and such Shares must be delivered pursuant to the book-entry transfer procedures described below under "Book-Entry Transfer" and a Book-Entry Confirmation (as defined below) must be received by the Depositary, in each case prior to the Expiration Date; or



•

the tendering stockholder must comply with the guaranteed delivery procedures described below under "Guaranteed Delivery" prior to the Expiration Date.

        The valid tender of Shares pursuant to one of the procedures described above will constitute a binding agreement between the tendering stockholder and the Purchaser upon the terms and subject to the conditions of the Offer.

The method of delivery of Shares, the Letter of Transmittal and all other required documents, including delivery through the Book-Entry Transfer Facility (as defined below), is at the election and risk of the tendering stockholder. Shares and other required materials will be deemed delivered only when actually received by the Depositary. If delivery is by mail, registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

        Book-Entry Transfer.    The Depositary will establish an account with respect to the Shares at The Depository Trust Company (the "Book-Entry Transfer Facility") for purposes of the Offer within two business days after the date of this Offer to Purchase. Any financial institution that is a participant of the Book-Entry Transfer Facility's system may make book-entry delivery of Shares by causing the Book-Entry Transfer Facility to transfer such Shares into the Depositary's account in accordance with the Book-Entry Transfer Facility's procedures for such transfer. However, although delivery of Shares may be effected through book-entry transfer into the Depositary's account at the Book-Entry Transfer Facility, the Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent's Message, and any other required documents, must be received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase prior to the Expiration Date for a valid tender of Shares by book-entry. The confirmation of a book-entry transfer of Shares into the Depositary's account at the Book-Entry Transfer Facility as described above is referred to herein as a "Book-Entry Confirmation." Delivery of documents to the Book-Entry Transfer Facility in accordance with the Book-Entry Transfer Facility's procedures does not constitute delivery to the Depositary.

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        The term "Agent's Message" means a message, transmitted by the Book-Entry Transfer Facility to, and received by, the Depositary and forming a part of a Book-Entry Confirmation, which states that the Book-Entry Transfer Facility has received an express acknowledgment from the participant in the Book-Entry Transfer Facility tendering the Shares that such participant has received and agrees to be bound by the terms of the Letter of Transmittal and that the Purchaser may enforce such agreement against the participant.

        Signature Guarantees.    No signature guarantee is required on the Letter of Transmittal if (1) the Letter of Transmittal is signed by the registered holder(s) (which term, for purposes of this Section 2, includes any participant in the Book-Entry Transfer Facility's system whose name appears on a security position listing as the owner of the Shares) of Shares tendered therewith and such registered holder has not completed either the box entitled "Special Delivery Instructions" or the box entitled "Special Payment Instructions" on the Letter of Transmittal or (2) such Shares are tendered for the account of a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program (such participant, an "Eligible Institution"). In all other cases, all signatures on the Letter of Transmittal must be guaranteed by an Eligible Institution. See Instructions 1 and 5 to the Letter of Transmittal. If (a) the certificates for Shares are not registered in the name of a person signing the Letter of Transmittal, (b) payment is to be made to a person other than the registered holder of the certificates surrendered, or (c) certificates for Shares not tendered or not accepted for payment are to be returned to a person other than the registered holder of the certificates surrendered, then the tendered certificates must be endorsed or accompanied by appropriate stock powers, in either case signed exactly as the name or names of the registered holders or owners appear on the certificates, with the signatures on the certificates or stock powers guaranteed by an Eligible Institution. See Instructions 1 and 5 to the Letter of Transmittal.

        Guaranteed Delivery.    If a stockholder desires to tender Shares pursuant to the Offer and such stockholder's certificates for Shares are not immediately available or the book-entry transfer procedures cannot be completed on a timely basis or time will not permit all required documents to reach the Depositary prior to the Expiration Date, such stockholder's tender may be effected if all the following conditions are met:

•

such tender is made by or through an Eligible Institution;



•

a properly completed and duly executed Notice of Guaranteed Delivery, substantially in the form provided by the Purchaser, is received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase prior to the Expiration Date; and



•

either (1) the certificates for tendered Shares together with a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees, and any other documents required by the Letter of Transmittal are received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase within three trading days after the date such Notice of Guaranteed Delivery is executed or (2) in the case of a book-entry transfer effected pursuant to the book-entry transfer procedures described above under "Book-Entry Transfer," (a) a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent's Message, and any other required documents, are received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase, (b) such Shares are delivered pursuant to the book-entry transfer procedures above and (c) a Book-Entry Confirmation is received by the Depositary, in each case within three trading days after the date such Notice of Guaranteed Delivery is executed. A "trading day" is any day on which the Nasdaq Stock Market is open for business.

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        The Notice of Guaranteed Delivery may be delivered by hand to the Depositary or transmitted by telegram, facsimile transmission or mail to the Depositary and must include a guarantee by an Eligible Institution in the form set forth in such Notice of Guaranteed Delivery.

        Appointment as Proxy.    By executing a Letter of Transmittal (or a manually signed facsimile thereof) or, in the case of a book-entry transfer, by delivering an Agent's Message in lieu of a Letter of Transmittal, a tendering stockholder will irrevocably appoint designees of the Purchaser as such stockholder's attorneys-in-fact and proxies in the manner set forth in the Letter of Transmittal, each with full power of substitution, to the full extent of such stockholder's rights with respect to the Shares tendered by such stockholder and accepted for payment by the Purchaser and with respect to any and all other Shares or other securities or rights issued or issuable in respect of such Shares on or after the date of this Offer to Purchase. All such powers of attorney proxies will be considered irrevocable and coupled with an interest in the tendered Shares. Such appointment will be effective when, and only to the extent that, the Purchaser accepts for payment Shares tendered by such stockholder as provided herein. Upon the effectiveness of such appointment, all prior powers of attorney, proxies and consents given by such stockholder with respect to such Shares or other securities or rights will, without further action, be revoked and no subsequent powers of attorney, proxies, consents or revocations may be given (and, if given, will not be effective). The designees of the Purchaser will thereby be empowered to exercise all voting and other rights with respect to such Shares and other securities or rights in respect of any annual, special or adjourned meeting of SangStat's stockholders, actions by written consent in lieu of any such meeting or otherwise, as they in their sole discretion deem proper. In order for Shares to be deemed validly tendered, immediately upon the Purchaser's acceptance for payment of such Shares, the Purchaser must be able to exercise full voting, consent and other rights with respect to such Shares and other securities or rights, including voting at any meeting of stockholders. The Offer does not constitute a solicitation of proxies, absent a purchase of Shares, for any meeting of SangStat stockholders.

        Determination of Validity.    All questions as to the validity, form, eligibility (including time of receipt) and acceptance of any tender of Shares will be determined by the Purchaser in its sole discretion, which determination will be final and binding. The Purchaser reserves the absolute right to reject any tenders determined by it not to be in proper form or any acceptance for payment of or payment for Shares which may, in the opinion of the Purchaser, be unlawful. The Purchaser also reserves the absolute right to waive any defect or irregularity in the tender of any Shares of any particular stockholder whether or not similar defects or irregularities are waived in the case of other stockholders. No tender of Shares will be deemed to have been validly made until all defects or irregularities relating thereto have been cured or waived. None of the Purchaser, Genzyme, SangStat, the Depositary, the Information Agent, the Dealer-Manager or any other person will be under any duty to give notification of any defects or irregularities in tenders or incur any liability for failure to give any such notification. The Purchaser's interpretation of the terms and conditions of the Offer (including the Letter of Transmittal and the instructions thereto and any other related documents thereto) will be final and binding.

        Backup Withholding.    In order to avoid "backup withholding" of U.S. federal income tax on payments of cash pursuant to the Offer, a stockholder surrendering Shares in the Offer must, unless an exemption applies, provide the Depositary with such stockholder's correct taxpayer identification number ("TIN") on a Substitute Form W-9, certify under penalties of perjury that such TIN is correct and provide certain other certifications. If a stockholder does not provide such stockholder's correct TIN or fails to provide the required certifications, the Internal Revenue Service (the "IRS") may impose a penalty on such stockholder and payment of cash to such stockholder pursuant to the Offer may be subject to backup withholding of 28%. All stockholders surrendering Shares pursuant to the Offer should complete and sign the main signature form and the Substitute Form W-9 included as part of the Letter of Transmittal to provide the information and certification necessary to avoid backup

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withholding (unless an applicable exemption exists and is proved in a manner satisfactory to the Purchaser and the Depositary). Certain stockholders (including, among others, all corporations) are not subject to backup withholding. Noncorporate foreign stockholders should complete and sign the main signature form included as part of the Letter of Transmittal and an appropriate Form W-8 (instead of a Form W-9), a copy of which may be obtained from the Depositary, in order to avoid backup withholding. See Instruction 9 to the Letter of Transmittal.

3.    Withdrawal Rights

        Except as otherwise provided in this Section 3, tenders of Shares are irrevocable.

        Shares tendered pursuant to the Offer may be withdrawn pursuant to the procedures set forth below at any time prior to the Expiration Date and, unless accepted for payment pursuant to the Offer, at any time on or after October 13, 2003. In the event the Purchaser provides a Subsequent Offering Period following the Offer, no withdrawal rights will apply to Shares tendered during such Subsequent Offering Period or to Shares tendered in the Offer and accepted for payment.

        For a withdrawal to be effective, a written or facsimile transmission notice of withdrawal must be timely received by the Depositary at one of its addresses set forth on the back cover of this Offer to Purchase and must specify the name of the person having tendered the Shares to be withdrawn, the number of Shares to be withdrawn and the name of the registered holder of the Shares to be withdrawn, if different from the name of the person who tendered the Shares. If certificates for Shares have been delivered or otherwise identified to the Depositary, then, prior to the physical release of such certificates, the serial numbers shown on such certificates must be submitted to the Depositary and, unless such Shares have been tendered by an Eligible Institution, any and all signatures on the notice of withdrawal must be guaranteed by an Eligible Institution. If Shares have been tendered pursuant to the book-entry transfer procedures described in Section 2, any notice of withdrawal must also specify the name and number of the account at the Book-Entry Transfer Facility to be credited with the withdrawn Shares and otherwise comply with the Book-Entry Transfer Facility's procedures. Withdrawals of tenders of Shares may not be rescinded, and any Shares validly withdrawn will thereafter be deemed not validly tendered for purposes of the Offer. However, withdrawn Shares may be retendered by again following one of the procedures described in Section 2 at any time prior to the Expiration Date.

        All questions as to the form and validity (including time of receipt) of any notice of withdrawal will be determined by the Purchaser in its sole discretion, which determination will be final and binding. None of the Purchaser, Genzyme, SangStat, the Depositary, the Information Agent, the Dealer-Manager or any other person will be under any duty to give notification of any defects or irregularities in any notice of withdrawal or incur any liability for failure to give any such notification.

The method of delivery of any documents related to a withdrawal is at the risk of the withdrawing stockholder. Any documents related to a withdrawal will be deemed delivered only when actually received by the Depositary. If delivery is by mail, registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

4.    Acceptance for Payment and Payment

        Upon the terms and subject to the prior satisfaction or waiver of the conditions of the Offer (including, if the Offer is extended or amended, the terms and conditions of any such extension or amendment), and provided that the Offer has not been terminated as described in Section 1 hereof, the Purchaser will accept for payment and will pay for all Shares validly tendered and not withdrawn prior to the Expiration Date promptly after the Expiration Date. If the Purchaser includes a Subsequent Offering Period, the Purchaser will immediately accept and promptly pay for Shares as they are

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tendered during the Subsequent Offering Period. The Purchaser, subject to the Merger Agreement, expressly reserves the right, in its sole discretion, to delay acceptance for payment of or payment for Shares in order to comply in whole or in part with any required regulatory or governmental approvals, including, without limitation, pursuant to the HSR Act, the German AARC, and any applicable pre-merger notification laws or regulations of other foreign jurisdictions. Any such delays will be effected in compliance with Rule 14e-1(c) under the Exchange Act (relating to a bidder's obligation to pay for or return tendered securities promptly after the termination or withdrawal of such bidder's offer). If the Purchaser is delayed in its acceptance for payment of or payment for Shares or is unable to accept for payment or pay for Shares pursuant to the Offer, then, without prejudice to the Purchaser's rights under the Offer (but subject to compliance with Rule 14e-1(c) under the Exchange Act), the Depositary may, nevertheless, on behalf of the Purchaser, retain tendered Shares, and such Shares may not be withdrawn except to the extent tendering stockholders are entitled to do so as described in Section 3.

        In all cases, payment for Shares accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of:

•

the certificates for such Shares, together with a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees; or



•

in the case of a transfer effected pursuant to the book-entry transfer procedures described in Section 2, a Book-Entry Confirmation and either a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, with any required signature guarantees, or an Agent's Message; and



•

any other required documents.

        The per Share consideration paid to any stockholder pursuant to the Offer will be the highest per Share consideration paid to any other stockholder pursuant to the Offer.

        For purposes of the Offer, the Purchaser will be deemed to have accepted for payment, and thereby purchased, Shares validly tendered to the Purchaser and not withdrawn as, if and when the Purchaser gives oral or written notice to the Depositary of the Purchaser's acceptance for payment of such Shares. Upon the terms and subject to the conditions of the Offer, payment for Shares accepted for payment pursuant to the Offer will be made by deposit of the purchase price therefor with the Depositary, which will act as an agent for tendering stockholders for the purpose of receiving payment from the Purchaser and transmitting payment to tendering stockholders whose Shares have been accepted for payment. Under no circumstances will interest be paid on the purchase price for tendered Shares, regardless of any extension of or amendment to the Offer or any delay in paying for such Shares.

        If any tendered Shares are not accepted for payment pursuant to the terms and conditions of the Offer for any reason, as promptly as practicable after the expiration or termination of the Offer, the certificates for such Shares will be returned and, if certificates are submitted for more Shares than are tendered, new certificates for the Shares not tendered will be sent, in each case without expense to the tendering stockholder (or, in the case of Shares delivered by book-entry transfer of such Shares into the Depositary's account at the Book-Entry Transfer Facility pursuant to the book-entry transfer procedures described in Section 2, such Shares will be credited to an account maintained at the Book-Entry Transfer Facility).

        The Purchaser reserves the right to transfer or assign, in whole or from time to time in part, to Genzyme, to one or more direct or indirect wholly owned subsidiaries of Genzyme or to Genzyme and one or more direct or indirect wholly-owned subsidiaries of Genzyme, the right to purchase Shares tendered pursuant to the Offer, but any such transfer or assignment will not relieve the Purchaser of its

14

obligations under the Offer and will in no way prejudice the rights of tendering stockholders to receive payment for Shares validly tendered and accepted for payment pursuant to the Offer.

5.    Certain U.S. Federal Income Tax Consequences

        The following is a general summary of certain U.S. federal income tax consequences relevant to a stockholder whose Shares are (1) tendered and purchased for cash pursuant to the Offer or (2) converted to cash in the Merger. This summary is based on the current provisions of the Internal Revenue Code of 1986, as amended (the "Code"), regulations issued thereunder, judicial decisions and administrative rulings, all of which are subject to change, possibly with retroactive effect. This summary is for general information only and does not address all aspects of U.S. federal income taxation that may be relevant to particular stockholders. The tax consequences to any particular stockholder may differ depending on that stockholder's own circumstances and tax position. For example, the following general summary may not be applicable with respect to Shares received pursuant to the exercise of employee stock options or otherwise as compensation or with respect to holders of Shares who are subject to special tax treatment under the Code, such as non-U.S. persons, life insurance companies, tax-exempt organizations and financial institutions. Stockholders are urged to consult their own tax advisors to determine the particular tax consequences to them (including the application and effect of any state, local or foreign income and other tax laws) of the Offer and the Merger.

        The receipt of cash pursuant to the Offer or the Merger will be a taxable transaction for U.S. federal income tax purposes and may also be a taxable transaction under applicable state, local or foreign income tax laws.

        Generally, for U.S. federal income tax purposes, a tendering stockholder or a stockholder who receives cash in exchange for Shares in the Merger will recognize gain or loss equal to the difference between the amount of cash received by the stockholder pursuant to the Offer or Merger and the adjusted tax basis in the Shares tendered by the stockholder and purchased pursuant to the Offer or converted into cash in the Merger, as the case may be. Gain or loss will be calculated separately for each block of Shares tendered and purchased pursuant to the Offer or converted into cash in the Merger, as the case may be. If tendered Shares or Shares converted into cash in the Merger are held by a stockholder as capital assets, gain or loss recognized by such stockholder will be capital gain or loss. Any capital gain or loss will be long-term capital gain or loss if such stockholder's holding period for the Shares exceeds one year. In the case of an individual stockholder, long-term capital gains will be eligible for a maximum U.S. federal income tax rate of 15%. The ability to use capital losses to offset ordinary income is limited.

        A stockholder (other than certain exempt stockholders including, among others, all corporations) may be subject to a 28% backup withholding tax, unless the stockholder provides its TIN and certifies that such number is correct (or properly certifies that it is awaiting a TIN), provides certain other certifications, and otherwise complies with the applicable requirements of the backup withholding rules. A stockholder that does not furnish a required TIN or that does not otherwise establish a basis for an exemption from backup withholding may also be subject to a penalty imposed by the IRS. See "Backup Withholding" under Section 2 of this Offer to Purchase. Each U.S. stockholder should complete and sign the Substitute Form W-9 included as part of the Letter of Transmittal so as to provide the information and certification necessary to avoid backup withholding. Non-U.S. stockholders should complete the appropriate Form W-8.

        If backup withholding applies to a stockholder, the Depositary is required to withhold 28% from payments to such stockholder. Backup withholding is not an additional tax. Rather, the amount of the backup withholding can be credited against the U.S. federal income tax liability of the person subject to the backup withholding, provided that the required information is given to the IRS. If backup

15

withholding results in an overpayment of tax, a refund can be obtained by the stockholder by filing a U.S. federal income tax return.

6.    Price Range of the Shares; Dividends on the Shares

        The Shares are listed on Nasdaq under the symbol "SANG". The following table sets forth, for each of the periods indicated, the high and low sales prices per Share as reported on Nasdaq:

SangStat Medical Corporation

		High		Low
Year Ended December 31, 2003:
	Third Quarter (through August 12, 2003)	$	22.48	$	12.83
	Second Quarter		16.46		10.80
	First Quarter		12.88		7.23
Year Ended December 31, 2002:
	Fourth Quarter	$	22.78	$	10.20
	Third Quarter		25.27		16.04
	Second Quarter		27.47		18.79
	First Quarter		27.49		17.00
Year Ending December 31, 2001:
	Fourth Quarter	$	24.87	$	15.88
	Third Quarter		19.06		12.35

        On August 1, 2003, the last full trading day before the public announcement of the execution of the Merger Agreement, the last reported sales price on Nasdaq of the Shares was $15.475 per Share. On August 12, 2003, the last reported sales price on Nasdaq of the Shares was $22.31 per Share. Stockholders are urged to obtain current market quotations for the Shares.

        The Purchaser has been advised by SangStat that SangStat has never declared or paid any cash dividends on the Shares and that it does not intend to declare or pay any cash dividends on the Shares in the foreseeable future. Under the Merger Agreement, SangStat is not permitted to declare or pay dividends with respect to the Shares without Genzyme's prior written consent.

7.    Possible Effects of the Offer on the Market for the Shares; Share Quotation; Exchange Act Registration; Margin Regulations

        Market for the Shares.    The purchase of Shares pursuant to the Offer will reduce the number of holders of Shares and the number of Shares that might otherwise trade publicly and could adversely affect the liquidity and market value of the remaining Shares held by the public.

        Share Quotation.    Depending upon the number of Shares purchased pursuant to the Offer, the Shares may no longer meet the requirements for continued inclusion on Nasdaq. A security must meet one of two maintenance standards for continued inclusion on Nasdaq. The first maintenance standard requires that there be at least $10 million in stockholders' equity, at least 750,000 publicly held shares, a market value of at least $5 million for all publicly held shares, a minimum bid price of $1, at least 400 shareholders of 100 shares or more, and at least two market makers for the shares. The second maintenance standard requires that either (1) the market value of listed securities is at least $50 million or (2) the Company has total assets and total revenue of at least $50 million each for the most recently completed fiscal year or two out of the last three most recently completed fiscal years; and, in either case, that there be at least 1.1 million publicly held shares, a market value of at least $15 million for all publicly held shares, a minimum bid price of $1, at least 400 shareholders of 100 shares or more, and at least four market makers for the shares. Shares held directly or indirectly by directors, officers or beneficial owners of more than 10% of the shares are not considered to be publicly held for the

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purpose of the maintenance standards. If, as a result of the purchase of Shares pursuant to the Offer, the Shares no longer meet these standards, the quotations for the Shares on Nasdaq will be discontinued.

        Exchange Act Registration.    The Shares are currently registered under the Exchange Act. Such registration may be terminated upon application of SangStat to the SEC if the Shares are neither listed on a national securities exchange nor held by 300 or more holders of record. Termination of registration of the Shares under the Exchange Act would reduce the information required to be furnished by SangStat to its stockholders and to the SEC and would make certain provisions of the Exchange Act no longer applicable to SangStat, such as the short-swing profit-recovery provisions of Section 16(b) of the Exchange Act, the requirement of furnishing a proxy or information statement pursuant to Section 14(a) or 14(c) of the Exchange Act in connection with stockholders' meetings and the related requirement of furnishing an annual report to stockholders, and the requirements of Rule 13e-3 under the Exchange Act with respect to "going private" transactions. Furthermore, the ability of "affiliates" of SangStat and persons holding "restricted securities" of SangStat to dispose of such securities pursuant to Rule 144 or 144A promulgated under the Securities Act of 1933, as amended, may be impaired or eliminated. The Purchaser intends to seek to cause SangStat to apply for termination of registration of the Shares under the Exchange Act as soon after the completion of the Offer as the requirements for such termination are met.

        Margin Regulations.    The Shares are currently "margin securities" under the regulations of the Board of Governors of the Federal Reserve System (the "Federal Reserve Board"), which has the effect, among other things, of allowing brokers to extend credit using Shares as collateral. Depending upon certain factors, such as the number of record holders of Shares and the number and market value of publicly held Shares, it is possible that, following the Offer, the Shares would no longer constitute "margin securities" for the purposes of the margin regulations of the Federal Reserve Board and therefore could no longer be used as collateral for loans made by brokers.

8.    Certain Information Concerning SangStat

        SangStat is a Delaware corporation with its principal offices at 6300 Dumbarton Circle, Fremont, California 94555. The telephone number at that location is (510) 789-4300. According to its 2002 Annual Report on Form 10-K filed with the SEC, SangStat is a publicly-held, global biopharmaceutical company focused on immunology and the development and marketing of therapeutic products in immunology, organ and bone marrow transplantation medicine, hematology/oncology and auto-immune disorders. SangStat and its subsidiaries have direct sales and marketing forces in all major European markets, the United States and Canada, and distributors throughout the rest of the world.

        Set forth below is certain selected financial information with respect to SangStat and its subsidiaries excerpted from the information contained in SangStat's annual reports on Form 10-K for the years ended December 31, 2002, 2001 and 2000, quarterly report on Form 10-Q for the quarter ended June 30, 2002, and current report on Form 8-K dated July 28, 2003. More comprehensive financial information is included in such reports and other documents filed by SangStat with the SEC, and the following summary is qualified in its entirety by reference to such reports, other documents and all the financial information (including any related notes) contained therein. Such reports and other documents are available for inspection and copies thereof may be obtained in the manner set forth below under "Available Information."

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SANGSTAT MEDICAL CORPORATION

SELECTED CONSOLIDATED FINANCIAL INFORMATION

(amounts in thousands)

		Year Ended December 31									Six Months Ended June 30
		2000			2001			2002			2002			2003
											(unaudited)
Consolidated Statement of Operations:
	Total revenues	$	63,145		$	94,509		$	120,057		$	55,061		$	62,950
	Income (loss) from continuing operations before provision (benefit) for income taxes		(41,649	)		(8,242	)		7,494			3,488			4,460
	Income tax benefit (provision)		(368	)		7			(1,145	)		(1,002	)		(861	)
	Net income (loss) from continuing operations		(42,017	)		(8,235	)		6,349			2,486			3,599
	Net income (loss) per share from continuing operations—Basic		(2.35	)		(0.40	)		0.25			0.10			0.14
Consolidated Balance Sheet Data:
	Total current assets	$	87,477		$	78,610		$	156,969		$	155,608		$	157,023
	Total assets		114,316			114,559			192,437			192,806			190,698
	Total current liabilities		47,703			45,344			43,439			46,738			47,788
	Total liabilities		92,392			82,200			62,517			69,155			55,283
	Total stockholders' equity		21,924			32,359			129,920			123,651			135,415

        Certain Projections.    During the course of discussions between representatives of Genzyme and SangStat, SangStat provided Genzyme or its representatives with certain non-public business and financial information about SangStat. This information included the following projections of total revenues, gross profit, operating income and net income for SangStat for the years ended December 31, 2003 through 2010.

2003 - 2010 CONSOLIDATED INCOME STATEMENTS—HIGHLIGHTS
(amounts in thousands)

	Budget		Forecast		Forecast		Forecast		Forecast		Forecast		Forecast		Forecast
	2003		2004		2005		2006		2007		2008		2009		2010
Revenues	$	135,900	$	170,200	$	151,600	$	182,100	$	253,800	$	316,800	$	414,800	$	485,800
Gross Profit		80,000		106,700		119,400		140,600		198,100		247,100		332,000		388,400
Operating Income		19,700		54,100		61,900		75,000		115,500		158,900		237,900		288,200
Net Income		16,400		50,000		58,500		69,900		108,600		116,200		172,500		209,100

        SangStat has advised Genzyme and the Purchaser of certain assumptions, risks and limitations regarding these projections, as described below.

        These projections were provided to Genzyme with the expectation that Genzyme would apply a substantial discount for the risks associated with the development and marketing of a Phase II product, with respect to RDP58, and the registration process, with respect to the cyclosporine capsule product. The review of these projections without applying a discount for the risks typically associated with the development and marketing of a new prescription pharmaceutical product would be inappropriate. SangStat advised Genzyme that SangStat has considered a broad range of discounts that may be appropriate in light of these development and marketing risks and, to date, has not formally adopted and incorporated any discounted projection into its internal operating plan nor has it comprehensively updated its guidance publicly since the announcement of the favorable clinical trial results of RDP58 in April 2003.

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        SangStat has advised Genzyme and the Purchaser that it does not as a matter of course make public any projections as to future performance or earnings, and the projections set forth above are included in this Offer to Purchase only because this information was provided to Genzyme and the Purchaser. Although Genzyme and the Purchaser were provided such projections, they did not base their analysis of SangStat on such projections. The projections were not prepared with a view to public disclosure or compliance with the published guidelines of the SEC or the guidelines established by the American Institute of Certified Public Accountants regarding projections or forecasts. The projections do not purport to present operations in accordance with U.S. generally accepted accounting principles ("GAAP"), and SangStat's independent auditors have not examined, compiled or otherwise applied procedures to the projections and accordingly assume no responsibility for them. SangStat has advised Genzyme and the Purchaser that its internal financial forecasts (upon which the projections provided to Genzyme and the Purchaser were based in part) are, in general, prepared solely for internal use and capital budgeting and other management decisions and are subjective in many respects and thus susceptible to interpretations and periodic revision based on actual experience and business developments. The projections also reflect numerous assumptions made by the management of SangStat, including assumptions with respect to approval by the U.S. Food and Drug Administration of a New Drug Application for RDP58 and the successful commercialization of RDP58, the market for SangStat's products and services and SangStat's ability to enter new geographic markets, the success of yield improvement programs, SangStat's ability to successfully negotiate and consummate potential strategic partnerships for products under development, effective tax rates, interest rates and currency exchange rates, the anticipated amount of borrowings by SangStat, and general business, economic, market and financial conditions and other matters, all of which are difficult to predict, many of which are beyond SangStat's control, and none of which were subject to approval by Genzyme or the Purchaser. Accordingly, there can be no assurance that the assumptions made in preparing the projections will prove accurate or that any of the projections will be realized. These projections were prepared in advance of and do not give effect to SangStat management's current expectations with respect to the terms and conditions of presently proposed partnering opportunities for RDP58.

        It is expected that there will be differences between actual and projected results, and actual results may be materially greater or less than those contained in the projections due to numerous risks and uncertainties, including, but not limited to, the accuracy of SangStat's information concerning the markets for its products and product candidates, including growth projections; whether competitors in the immunology field increase sales of their products, implement price reductions or introduce new products; the actual timing and content of submissions to and decisions made by regulatory authorities in the United States, Europe and elsewhere, including decisions regarding marketing authorizations, product pricing and facilities; market acceptance of products in expanded areas of use and in new geographic markets; the actual design, results and timing of preclinical and clinical studies; enrollment rates for clinical trials; potential reduction in margin on key products and increases in expenses; the availability and extent of reimbursement from third-party payers for SangStat's products and services; the scope, validity and enforceability of patents and other proprietary rights held by third parties and the actual impact of such patents and other rights, if any, on SangStat's ability to commercialize products; patent and other litigation; the ability to manufacture sufficient quantities of products for development and commercialization activities and to do so in a timely and cost efficient manner; SangStat's ability to obtain and maintain agreements with suppliers, licensors and sublicensees, and distributors; the ability to attract and retain qualified sales forces; the impact, if any, of war and terrorist activities on the operations and activities of SangStat and third parties, including regulatory authorities; and the risks and uncertainties described in reports filed by SangStat with the SEC under the Exchange Act, including without limitation under the heading "Risk Factors" in SangStat's 2002 Annual Report on Form 10-K. All projections are forward-looking statements; these and other forward-looking statements are expressly qualified in their entirety by the risks and uncertainties

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identified above and the cautionary statements contained in SangStat's 2002 Annual Report on Form 10-K filed with the SEC.

        The inclusion of the projections herein should not be regarded as an indication that any of Genzyme, the Purchaser, SangStat or their respective affiliates or representatives considered or consider the projections to be a reliable prediction of future events, and the projections should not be relied upon as such. None of Genzyme, the Purchaser, SangStat or any of their respective affiliates or representatives has made or makes any representation to any person regarding the ultimate performance of SangStat compared to the information contained in the projections, and none of them intends to update or otherwise revise the projections to reflect circumstances existing after the date such projections were generated or to reflect the occurrence of future events even in the event that any or all of the assumptions underlying the projections are shown to be in error.

Stockholders are cautioned not to place undue reliance on the financial projections included in this Offer to Purchase.

        Available Information.    SangStat is subject to the informational requirements of the Exchange Act and, in accordance therewith, is required to file reports and other information with the SEC relating to its business, financial condition and other matters. Certain information as of particular dates concerning SangStat's directors and officers, their remuneration, stock options and other matters, the principal holders of SangStat's securities and any material interest of such persons in transactions with SangStat is required to be disclosed in SangStat's proxy statements distributed to SangStat's stockholders and filed with the SEC. Such reports, proxy statements and other information are available for inspection at the SEC's public reference facility at 450 Fifth Street, N.W., Washington, DC 20549, from commercial document retrieval services and at the Internet world wide web site maintained by the SEC at http://www.sec.gov. Additional information regarding the SEC's facilities may be obtained by calling the SEC at 1-800-SEC-0330.

        Except as otherwise stated in this Offer to Purchase, the information concerning SangStat contained herein has been taken from or based upon publicly available documents on file with the SEC and other publicly available information. Although Genzyme and the Purchaser do not have any knowledge that any such information is untrue, neither Genzyme nor the Purchaser takes any responsibility for the accuracy or completeness of such information or for any failure by SangStat to disclose events that may have occurred and may affect the significance or accuracy of any such information.

9.    Certain Information Concerning Genzyme and the Purchaser

        Genzyme Corporation is a Massachusetts corporation with its principal executive offices located at One Kendall Square, Cambridge, Massachusetts 02139. The telephone number at that location is (617) 252-7500. Genzyme is a publicly-held, global biotechnology company that develops and commercializes solutions for the medical needs of patients with serious diseases. The company's broad product portfolio is focused on rare genetic disorders, renal disease, and osteoarthritis, and includes an industry-leading array of diagnostic products and services. Genzyme's 5,300 employees worldwide serve patients in more than 80 countries. Genzyme's shares are traded on Nasdaq under the symbol "GENZ."

        Genzyme files annual, quarterly and special reports, proxy statements and other information with the SEC. Such reports, proxy statements and other information are available for inspection at the SEC's public reference facility at 450 Fifth Street, N.W., Washington, DC 20549, from commercial document retrieval services and at the Internet world wide web site maintained by the SEC at http://www.sec.gov.

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        The Purchaser, Swift Starboard Corporation, is a Delaware corporation that was recently incorporated for the purpose of acquiring the Shares and, to date, has engaged in no other activities other than those incidental to the Offer and the Merger Agreement. The Purchaser is a wholly-owned subsidiary of Genzyme. Until immediately prior to the time the Purchaser purchases Shares pursuant to the Offer, it is not anticipated that the Purchaser will have any significant assets or liabilities or engage in activities other than those incidental to the Purchaser's formation and capitalization and the transactions contemplated by the Offer. The Purchaser is not subject to the informational filing requirements of the Exchange Act. The principal executive offices of the Purchaser are located c/o Genzyme at One Kendall Square, Cambridge, Massachusetts 02139. The telephone number at that location is (617) 252-7500.

        The name, business address, citizenship, past and present principal occupations during the past five years of each of the executive officers and directors of Genzyme and the Purchaser are set forth in Annex I to this Offer to Purchase.

        Neither Genzyme, the Purchaser, nor, to the best knowledge of Genzyme and the Purchaser, any of the persons listed in Annex I to this Offer to Purchase has, during the past five years, been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors). Neither Genzyme, the Purchaser, nor, to the best knowledge of Genzyme and the Purchaser, any of the persons listed in Annex I has, during the past five years, been a party to any judicial or administrative proceeding (except for matters that were dismissed without sanction or settlement) that resulted in a judgment, decree or final order enjoining the person from future violations of, or prohibiting activities subject to, United States federal or state securities laws, or a finding of any violation of federal or state securities laws.

        Past Contacts, Transactions, Negotiations and Agreements.    Except as set forth in Section 11 "Contacts and Transactions with SangStat; Background of the Offer" of this Offer to Purchase and elsewhere in this Offer to Purchase:

•

none of Genzyme, the Purchaser, or, to the best knowledge of Genzyme and the Purchaser, any of the persons listed in Annex I to this Offer to Purchase, or any associate or majority-owned subsidiary of any of the foregoing, (1) beneficially owns or has a right to acquire any Shares or any other equity securities of SangStat, (2) has any contract, arrangement, understanding or relationship with any other person with respect to any securities of SangStat, or (3) has effected any transaction in the Shares or any other equity securities of SangStat during the past 60 days;



•

there have not been any transactions during the past two years which would be required to be disclosed under the rules and regulations of the SEC between any of Genzyme, the Purchaser, any of their respective subsidiaries, or, to the best knowledge of Genzyme and the Purchaser, any of the persons listed in Annex I to this Offer to Purchase, on the one hand, and SangStat or any of its executive officers, directors or affiliates, on the other hand; and



•

there have not been any negotiations, transactions or material contacts during the past two years between any of Genzyme, the Purchaser, any of their respective subsidiaries or, to the best knowledge of Genzyme and the Purchaser, any of the persons listed in Annex I to this Offer to Purchase, on the one hand, and SangStat or its affiliates, on the other hand, concerning any merger, consolidation, acquisition, tender offer for or other acquisition of any class of securities of SangStat, any election of directors of SangStat, or any sale or other transfer of a material amount of assets of SangStat.

        Each of Genzyme and the Purchaser disclaims that it is an "affiliate" of SangStat within the meaning of Rule 13e-3 under the Exchange Act.

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10.    Source and Amount of Funds

        The Purchaser estimates that the total amount of funds required to purchase all 26,469,087 Shares that were outstanding as of June 30, 2003 pursuant to the Offer and to pay related fees and expenses will be approximately $600 million.

        In connection with the Merger, (1) all outstanding options to purchase Shares under SangStat's option plans will become fully vested and cancelled in exchange for a cash payment by Genzyme or the Purchaser to each option holder equal to the product of (a) the amount, if any, by which $22.50 (or the highest price paid for any Share in the Offer) exceeds the per Share exercise price of such option holder's options and (b) the number of shares underlying such option holder's options and (2) Genzyme will assume an outstanding convertible promissory note in the principal amount of $10 million issued by SangStat, unless the note holder converts such note into Shares before the Merger. Genzyme estimates that the total amount of funds necessary to satisfy the foregoing obligations will be approximately $41 million.

        Genzyme will ensure that the Purchaser has sufficient funds to acquire all of the outstanding Shares pursuant to the Offer and to fulfill its obligations under the Merger Agreement. Genzyme will be able to provide the Purchaser with the necessary funds from its available cash balances and an existing credit facility.

        As of June 30, 2003, Genzyme had approximately $1.3 billion in cash, cash equivalents and short-and long-term investments. Genzyme and certain of its subsidiaries are parties to an Amended and Restated Credit Agreement dated December 14, 2000 (the "Credit Agreement") with Fleet National Bank, as Administrative Agent, ABN AMRO Bank, N.V., as Syndication Agent, and First Union National Bank, as Documentation Agent, and other lenders. Under the Credit Agreement, Genzyme has access to a $350 million revolving credit facility, all of which matures in December 2003. As of June 30, 2003, $300 million was outstanding under this facility. Borrowings under this facility bear interest at LIBOR plus an applicable margin, which was, in the aggregate, 2.5% at June 30, 2003. The terms of the revolving credit facility include various covenants, including financial covenants, which require Genzyme to meet minimum liquidity and interest coverage ratios and to meet maximum leverage ratios. Genzyme has pledged stock of Genzyme Securities Corporation as collateral under the credit facility. The foregoing summary of the revolving credit facility does not purport to be a complete description of the terms and conditions of the revolving credit facility and is qualified in its entirety by reference to the Credit Agreement itself, which is an exhibit to the Tender Offer Statement on Schedule TO that Genzyme and the Purchaser have filed with the SEC and which is hereby incorporated in this Offer to Purchase by reference. Copies of the Tender Offer Statement on Schedule TO together with all exhibits thereto, including the Credit Agreement, may be obtained and examined as set forth in Section 9 "Certain Information Concerning Genzyme and the Purchaser." If Genzyme were to borrow funds under the revolving credit facility in connection with the acquisition of SangStat, Genzyme would do so with the intent to repay such borrowings from working capital and funds provided by future operations. Genzyme intends to refinance the revolving credit facility prior to its expiration in December 2003 irrespective of whether it borrows funds under the revolving credit facility in connection with the acquisition of SangStat.

        The Offer is not contingent upon the Purchaser or Genzyme establishing any financing arrangements.

11.    Contacts and Transactions with SangStat; Background of the Offer

        During the week of February 17, 2003, representatives of Genzyme and SangStat met to discuss informally the businesses of the two companies. On February 27, 2003, Genzyme sent a letter to SangStat stating Genzyme's interest in pursuing a business combination.

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        During the following days, discussions continued between Mr. James Geraghty, Senior Vice President of Genzyme, Mr. Jan van Heek, Executive Vice President of Genzyme and Mr. Richard Murdock, then-acting Chief Executive Officer of SangStat. Discussions terminated in March 2003 due to, among other things, the pending clinical trials with RDP58.

        On June 3, 2003, SangStat received a letter from a party other than Genzyme that was interested in acquiring all of the outstanding stock of SangStat on specific proposed terms at a substantial premium to the then-current trading price. On June 5, 2003, Mr. Murdock, Chief Executive Officer and President of SangStat, convened a meeting of the SangStat Board to review the terms of the offer and to discuss SangStat's response and its alternatives. Thereafter, the Board retained the services of Merrill Lynch & Co. ("Merrill Lynch") to advise SangStat. The Board determined not to sell SangStat at that time but instructed management, in general, to continue operating the business in the ordinary course and, in particular, to continue to pursue partnering arrangements that SangStat had been pursuing since April 2003. The Board also instructed Merrill Lynch to investigate a possible sale transaction through an auction process.

        During the solicitation process undertaken by Merrill Lynch, on June 6, 2003, Mr. Murdock contacted Mr. van Heek to inquire about Genzyme's potential interest in a transaction at that time, since Genzyme had previously expressed interest in pursuing a business combination.

        On or about June 11, 2003, Genzyme engaged Credit Suisse First Boston LLC ("Credit Suisse First Boston") as its financial advisor in connection with a potential acquisition of SangStat.

        Representatives at Merrill Lynch subsequently contacted representatives at Credit Suisse First Boston to solicit interest in a potential business combination.

        On June 12, 2003, SangStat and Genzyme entered into a confidentiality agreement regarding a potential business combination. Thereafter, Mr. Murdock and selected members of the management team of SangStat, as well as representatives from Merrill Lynch and Skadden, Arps, Slate, Meagher & Flom LLP ("Skadden, Arps"), SangStat's legal advisor, participated in a conference call with Mr. Geraghty and selected members of the management team of Genzyme, as well as representatives from Credit Suisse First Boston. SangStat's senior management provided Genzyme with an overview of SangStat's operations, products and development programs. The parties also discussed potential benefits of a transaction and potential issues related to a transaction, as well as due diligence issues that required further analysis by Genzyme.

        On June 16, 2003, Genzyme delivered a letter to SangStat expressing Genzyme's interest in exploring a potential acquisition by Genzyme of all of the outstanding capital stock of SangStat for $20.00 per share, to be paid in shares of Genzyme General Division common stock, subject to a collar limiting any increase or decrease in the number of shares to be issued.

        On June 17, 2003 and June 19, 2003, representatives from Merrill Lynch contacted representatives from Credit Suisse First Boston to discuss the terms of Genzyme's proposal. The parties discussed, among other things, the value of Genzyme's proposal relative to the other proposals received by SangStat. On June 17, 2003, Genzyme also submitted a preliminary due diligence request list to SangStat.

        On June 23, 2003, representatives of Merrill Lynch informed representatives of Credit Suisse First Boston that, in light of expressions of interest by other parties, an offer for an all-stock transaction at $20.00 per share was unlikely to be adequate.

        On June 25, 2003, Mr. van Heek contacted Mr. Murdock to express Genzyme's continued interest in pursuing a potential strategic transaction. On behalf of Genzyme, representatives from Credit Suisse First Boston contacted representatives from Merrill Lynch to discuss the revised terms of Genzyme's proposal, which included increasing the offer price to $22.00 per share and changing the form of

23

consideration to be paid to fifty percent (50%) in cash and fifty percent (50%) in shares of Genzyme General Division common stock. Mr. Termeer sent a letter to SangStat specifying revised terms and a proposed timeframe for a potential business combination transaction.

        On June 27, 2003, Messrs. Adrian Arima, Senior Vice President and General Counsel of SangStat, and Stephen G. Dance, Chief Financial Officer of SangStat, and representatives from Merrill Lynch and Skadden, Arps participated in a conference call with Mr. Geraghty, Ms. Tracey McCain, Vice President and Deputy General Counsel of Genzyme, other members of the Genzyme management team and representatives from Credit Suisse First Boston and Ropes & Gray LLP ("Ropes & Gray"), Genzyme's legal advisor, to discuss the due diligence request list submitted by Genzyme. The parties discussed areas of concern and confirmed plans for Genzyme, Credit Suisse First Boston and Ropes & Gray to visit SangStat's data room in the offices of Skadden, Arps in Palo Alto, California.

        During the following weeks, beginning on July 7, 2003, there were a number of additional meetings and conversations between the management of SangStat and Genzyme and their respective financial advisors regarding a possible transaction and to conduct due diligence regarding SangStat's business. During the period, representatives of Genzyme together with Credit Suisse First Boston and Ropes & Gray, conducted legal, financial and operational due diligence investigation of SangStat. Members of SangStat's senior management also made presentations to Genzyme and Credit Suisse First Boston about SangStat's business and operations between July 7th and July 10th at the offices of Skadden Arps in Palo Alto, California.

        On July 8, 2003, Messrs. Murdock, van Heek and Geraghty, along with representatives from Merrill Lynch and Credit Suisse First Boston, met to discuss SangStat's business and its strategic initiatives. Mr. Murdock provided an update on the status of discussions regarding potential partnership arrangements for SangStat's product in development, RDP58. The parties agreed to continue to explore the merits and issues associated with a potential business combination transaction.

        Also on July 8, 2003, Merrill Lynch delivered a letter to Mr. Geraghty inviting Genzyme to submit an updated offer to acquire SangStat. The letter was accompanied by a draft merger agreement and noted that other unspecified interested parties were receiving a similar invitation.

        On July 14, 2003 and July 15, 2003, Genzyme diligence team members met with Messrs. Prasad and Levy in Lyon, France and at SangStat's Marcy l'Etoile facility. Genzyme representatives were given a plant tour and the opportunity to review documents regarding the manufacturing operations in Marcy l'Etoile.

        On July 17, 2003, Mr. Lundstrom and Mr. Fong visited Genzyme's headquarters in Cambridge, Massachusetts to provide a presentation regarding the humanized polyclonals development program and the RDP58 development program to the Genzyme scientific diligence team. The Genzyme team was given the opportunity to ask questions regarding the programs.

        Also on July 17, 2003, Genzyme held a special meeting of its Board of Directors to consider the proposed acquisition of SangStat. After presentations from members of Genzyme's management and Genzyme's advisors, Genzyme's Board of Directors conditionally approved a business combination with SangStat provided that agreement could be reached within financial parameters established by the Board of Directors. The Board of Directors also appointed a special merger committee consisting of Messrs. Robert Carpenter, Charles Cooney and Henri Termeer and delegated authority to the special merger committee to continue evaluating the proposed transaction, to negotiate the terms and to execute a definitive agreement, all within the financial parameters established by the Board of Directors at the meeting.

        On July 20, 2003, Merrill Lynch distributed a letter to Genzyme establishing the deadline for submitting an updated bid to acquire SangStat. The letter requested that Genzyme's bid be submitted by July 24, 2003.

24

        On July 22, 2003, Ms. McCain and Mr. Jonathan Lloyd-Jones, Senior Director, Corporate Development of Genzyme visited the New York City offices of Skadden, Arps to review additional documents SangStat had made available to prospective bidders.

        On July 23, 2003, Mr. Geraghty and Dr. Naseem Amin, Vice President of Genzyme, visited SangStat's offices in Fremont, California. Mr. Geraghty and Dr. Amin gave a presentation to Messrs. Murdock, Dance, Arima, Lundstrom and Aselage, as well as to representatives of Merrill Lynch and Skadden, Arps, regarding Genzyme's business and its financial performance. Messrs. Murdock, Arima, Dance and Geraghty, Ms. McCain and Peter Wirth, Executive Vice President and Chief Legal Officer of Genzyme, and other Genzyme representatives and representatives of Ropes & Gray participated in a conference call to discuss certain questions Genzyme had based on their due diligence review. Mr. Geraghty also met with Mr. Murdock and representatives of Merrill Lynch and Skadden, Arps to discuss the terms of their proposal, including the form of consideration and the structure of the business combination. Mr. Geraghty also spent time with Mr. Murdock and SangStat's management team discussing the RDP58 development program and the status of the efforts to license out RDP58.

        On July 24, 2003, Genzyme submitted an updated letter to SangStat confirming its intent to acquire all of the outstanding capital stock of SangStat in a transaction structured as a merger for $22.00 per share consisting of $11.00 in cash and $11.00 in Genzyme General Division common stock, and providing for a collar limiting the increase or decrease in the number of shares Genzyme General Division common stock to be issued. Genzyme indicated in the letter its willingness to discuss alternative transaction structures and alternative forms of consideration. Genzyme also submitted a mark-up of the draft merger agreement provided previously by SangStat.

        On July 27, 2003, SangStat's Board of Directors met and considered Genzyme's proposal along with other proposals received by SangStat.

        On July 29, 2003, Merrill Lynch called Credit Suisse First Boston to communicate SangStat's response to Genzyme's proposal and inquire about Genzyme's willingness to consider structuring the transaction as an all-cash tender offer at a higher price.

        Following these discussions, on July 29, 2003, Genzyme notified SangStat that it was willing to modify the transaction structure to provide for an all-cash tender offer for $22.50 per share provided that SangStat agree to negotiate exclusively with Genzyme.

        On July 30, 2003, Messrs. Murdock, Arima, Dance, Geraghty and Wirth, Ms. McCain and other Genzyme representatives along with representatives from Merrill Lynch, Credit Suisse First Boston, Skadden, Arps and Ropes & Gray participated in a conference call to discuss Genzyme's proposed timeline and other issues related to Genzyme's proposed bid. The parties agreed to further evaluate the proposed terms of Genzyme's offer pending instructions from the Board.

        Later on July 30, 2003, SangStat convened a meeting of its Board. Messrs. Murdock, Dance and Arima and representatives from Merrill Lynch and Skadden, Arps participated in a conference call. The SangStat Board reviewed the terms of Genzyme's revised proposal and discussed the status of the other interested parties. After consultation with Merrill Lynch and Skadden, Arps, the SangStat Board authorized and directed management to actively pursue further discussions with Genzyme, but no exclusivity agreement was ever signed.

        From July 31, 2003 through August 1, 2003, members of the Genzyme diligence team visited SangStat's facility in Marcy l'Etoile, France for a second time to conduct further due diligence. Mr. Prasad met with representatives from Genzyme to provide access to additional documents and answer questions.

25

        On July 31, 2003, Genzyme submitted a new mark-up of a draft merger agreement reflecting a tender offer structure.

        On August 1, 2003, the special merger committee of Genzyme's Board of Directors met with Genzyme management and Genzyme's legal and financial advisors to consider the revised terms of the Merger Agreement. After discussions, by unanimous vote the special merger committee approved the proposed terms of the Offer, the Merger and the Merger Agreement, determined that the terms of the Offer and the Merger are in the best interests of the Genzyme and the Purchaser and that the Merger is advisable, and authorized management to negotiate and execute the Merger Agreement within the parameters discussed by the special merger committee. The Board of Directors of the Purchaser adopted similar resolutions.

        From August 1, 2003 through August 3, 2003, representatives from Ropes & Gray and Skadden, Arps met in the Skadden, Arps Palo Alto, California offices to discuss Genzyme's proposed terms to enter into a binding merger agreement. Further due diligence was conducted at this time. Representatives from Skadden, Arps and Ropes & Gray exchanged drafts and negotiated terms throughout this time period to attempt to finalize the terms of the Merger Agreement.

        On August 1, 2003, Messrs. Geraghty and Murdock, along with representatives from Skadden, Arps and Ropes & Gray, met in the late afternoon in the Skadden, Arps offices. The parties discussed a brief list of business points that required resolution. After reviewing the issues, the parties adjourned their meeting, and Messrs. Geraghty and Murdock continued their discussion in a separate meeting that evening.

        On August 2, 2003, representatives from Skadden, Arps and Ropes & Gray met throughout the day and continued their discussions.

        On August 3, 2003, Messrs. Geraghty and Murdock met during the morning to address the remaining issues.

        On August 3, 2003, the SangStat Board met to review and consider the Genzyme proposal. Mr. Murdock updated the Board on the status of negotiations with Genzyme, and Skadden, Arps summarized the terms of the merger agreement as presently proposed. Merrill Lynch also advised the board of the status of the other proposals. The Board then considered the possibility of remaining independent and pursuing partnering options for RDP58 then available, and compared this against the value of the sale offers received to date, including the revised Genzyme offer. In doing so, the Board considered, among other things, the various risks and benefits relating to remaining independent, including the development and other risks related to RDP58, against the benefits of the Genzyme offer, including the substantial premium, which appeared to fully reflect, among other things, the present value of the RDP58 opportunity. In this regard, the Board considered, among other things, the fact that the RDP clinical results were from early Phase II studies with small numbers of patients, that toxicology data were limited to short-term studies, and that many pharmaceutical products fail in Phase III trials. The Board also considered the comprehensive partnering and sale processes undertaken to ensure that these were the best terms available to SangStat. Thereafter, Merrill Lynch provided its financial analysis and fairness opinion to the Board. After discussion among the participants in the meeting to address questions from the Board, the Board by a unanimous vote, approved the Merger Agreement and the transactions contemplated by the Merger Agreement including the Offer and the Merger, determined that the terms of the Offer and the Merger are fair to, and in the best interests of, SangStat and its stockholders, recommended that the stockholders of SangStat accept the Offer and tender their Shares to the Purchaser pursuant to the Offer, determined that the Merger Agreement is advisable and recommended that the stockholders of SangStat approve the Merger Agreement, to the extent such approval is required by applicable law.

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        On August 4, 2003, SangStat and Genzyme executed the Merger Agreement and issued a press release announcing the execution of the Merger Agreement.

        On August 13, 2003, Genzyme and the Purchaser commenced the Offer.

12.    Purpose of the Offer; the Merger Agreement; Plans for SangStat

Purpose

        The purpose of the Offer is to enable Genzyme, through the Purchaser, to acquire control of SangStat and to effect the first step in the acquisition of all of the outstanding Shares. The purpose of the Merger is to acquire all outstanding Shares not tendered and purchased pursuant to the Offer or otherwise.

The Merger Agreement

        The following summary of the Merger Agreement is qualified in its entirety by reference to the Merger Agreement itself, which is an exhibit to the Tender Offer Statement on Schedule TO that Genzyme and the Purchaser have filed with the SEC and which is hereby incorporated in this Offer to Purchase by reference. Copies of the Tender Offer Statement on Schedule TO together with all exhibits thereto, including the Merger Agreement, may be obtained and examined as set forth in Section 9 "Certain Information Concerning Genzyme and the Purchaser." Stockholders should read the Merger Agreement in its entirety for a more complete description of the matters summarized below.

        The Offer.    The Merger Agreement provides that the Purchaser will commence the Offer as soon as practicable following the date of the Merger Agreement and in no event later than 10 business days following such date and that, upon the terms and subject to the prior satisfaction or waiver of the conditions of the Offer, the Purchaser will purchase all Shares validly tendered and not withdrawn pursuant to the Offer. The conditions of the Offer are set forth in Section 14 "Certain Conditions of the Offer" of this Offer to Purchase.

        Option to Purchase Shares.    The Merger Agreement grants the Purchaser an option to purchase up to the number of newly issued shares of SangStat common stock that represent 19.9% of the outstanding Shares for a purchase price of $22.50 per share (or the highest price paid for any Share in the Offer). This option is exercisable only if the Purchaser has acquired at least 75% but less than 90% of the outstanding Shares pursuant to the Offer. The purpose of this option is to facilitate a short-form merger following completion of the Offer.

        The Merger.    The Merger Agreement provides that, following the satisfaction or waiver of the conditions described below under "Conditions to the Merger," the Purchaser will be merged with and into SangStat, with SangStat being the surviving corporation and becoming a wholly-owned subsidiary of Genzyme. Each issued Share (other than Shares owned by Genzyme, the Purchaser or SangStat, or by stockholders, if any, who are entitled to and who properly exercise appraisal rights under Delaware law) will be converted into the right to receive the highest price per Share paid pursuant to the Offer in cash, without interest thereon.

        Vote Required To Approve Merger.    The DGCL requires, among other things, that SangStat's board of directors approve any plan of merger of SangStat and, if the "short-form" merger procedure described below is not available, that the holders of a majority of SangStat's outstanding voting securities approve the plan of merger. The board of directors of SangStat has already approved the Offer, the Merger and the Merger Agreement. If the short-form merger procedure is not available for the Merger, SangStat's stockholders will need to approve the Merger Agreement. If required by the DGCL, SangStat will call and hold a meeting of its stockholders as soon as reasonably practicable following the consummation of the Offer (subject to any waiting periods required by statute or

27

regulation) for the purpose of approving the Merger Agreement. If the Minimum Condition in the Offer is satisfied and the Purchaser accepts for payment Shares tendered pursuant to the Offer, the Purchaser will have sufficient voting power to approve the Merger Agreement at a meeting of SangStat stockholders without the affirmative vote of any other SangStat stockholder.

        "Short-Form" Merger Procedure.    The DGCL also provides that, if a parent company owns at least 90% of the outstanding shares of each class of a subsidiary's stock entitled to vote to approve a merger agreement, the parent company may merge that subsidiary with the parent company pursuant to the "short-form" merger procedures without prior notice to, or the approval of, the other stockholders of the subsidiary. In order to consummate the Merger pursuant to these provisions of the DGCL, the Purchaser would have to own at least 90% of the outstanding Shares of SangStat. If Purchaser is able to consummate the Merger pursuant to these provisions of the DGCL, the closing of the Merger would take place as soon as practicable after the closing of the Offer, without any notice to or approval of the other stockholders of SangStat.

        Conditions to the Merger.    The Merger Agreement provides that the obligations of each party to effect the Merger are subject to the satisfaction or waiver of certain conditions, including the following:

•

SangStat's stockholders shall have approved the Merger by an affirmative vote of the holders of a majority of the outstanding Shares (the "SangStat Stockholder Approval"), if required;



•

no statute, rule, executive order or regulation shall have been enacted, issued, enforced or promulgated by any arbitrator, court, nation, government, any state or other political subdivision thereof and any entity exercising executive, legislative, judicial, regulatory or administrative functions of, or pertaining to, government (each a "Governmental Entity") which prohibits the consummation of the Merger, and there shall be no order or injunction of a court of competent jurisdiction in effect preventing consummation of the Merger;



•

the Purchaser shall have purchased all Shares properly tendered pursuant to the Offer; provided, that this condition shall be deemed to have been satisfied with respect to the obligation of Genzyme and the Purchaser if the Purchaser fails to accept for payment or pay for Shares validly tendered pursuant to the Offer in violation of the terms of the Offer or the Merger Agreement;



•

the applicable waiting period under the HSR Act, the German AARC and any comparable provisions under any applicable pre-merger notification laws or regulations of other foreign jurisdictions shall have expired or been terminated; and



•

fewer than 10% of the outstanding Shares shall have properly exercised appraisal rights under Delaware law.

In addition, the obligations of Genzyme and the Purchaser to consummate and effect the Merger are subject to SangStat having provided certain notices and taken other actions required by the Merger Agreement with respect to outstanding stock options and an outstanding warrant as described below under "Stock Options and Warrant" and with respect to an outstanding promissory note as described below under "Promissory Note."

        Termination of the Merger Agreement.    The Merger Agreement may be terminated at any time prior to the effective time of the Merger (the "Effective Time"), whether before or after adoption of the Merger Agreement by the stockholders of SangStat:

(a)

by mutual written consent of Genzyme and SangStat;



(b)

by either Genzyme or SangStat, if a court of competent jurisdiction or other Governmental Entity shall have issued an order, decree or ruling or taken any other action, or there shall exist any statute, rule or regulation, in each case permanently restraining, enjoining or

28

otherwise prohibiting (collectively the "Restraints") the consummation of the Offer, the Merger or the other transactions contemplated by the Merger Agreement or if any Governmental Entity that must approve the Merger has denied approval of the Merger; provided, that the party seeking to terminate the Merger Agreement for this reason shall have used all reasonable efforts to prevent the entry of and to remove such Restraint or to obtain the approval of the Governmental Entity;

(c)

by either Genzyme or SangStat, if the Merger has not been consummated by January 31, 2004 (the "Termination Date") at any time after the Termination Date, unless the party seeking to terminate the Merger Agreement has expressly restricted in writing its right to terminate the Merger Agreement after the Termination Date; provided, that this termination right will not be available to any party whose action or failure to fulfill any obligation under the Merger Agreement has been the principal cause of, or resulted in, the failure of the Merger to be consummated by the Termination Date;



(d)

by Genzyme, if before the purchase of Shares pursuant to the Offer, there has been a material breach by SangStat of any representation, warranty, covenant or agreement in the Merger Agreement, and such breach resulted or is reasonably likely to result in any condition to the Offer set forth in Section 14 of this Offer to Purchase not being satisfied (and such breach has not been cured or such condition has not been satisfied within 20 days after the receipt of notice thereof, or such breach is not reasonably capable of being cured or such condition is not reasonably capable of being satisfied within such period);



(e)

by Genzyme, if due to an occurrence or circumstance that has resulted or would result in a failure to satisfy any condition set forth in Section 14 of this Offer to Purchase, the Purchaser shall have (1) failed to commence the Offer within 10 business days following the date of the Merger Agreement, (2) terminated the Offer, or allowed the offer to terminate, without having accepted any Shares for payment or (3) failed to accept Shares for payment pursuant to the Offer prior to the Termination Date, unless such action or inaction under clauses (1), (2) or (3) shall have been caused by or resulted from either the failure of Genzyme or the Purchaser to perform, in any material respect, any of their covenants or agreements contained in the Merger Agreement, or the material breach by Genzyme or the Purchaser of any of their representations or warranties contained in the Merger Agreement;



(f)

by SangStat, if before the purchase of Shares pursuant to the Offer that would represent a majority of the Fully Diluted Shares (as defined in Section 14 of this Offer to Purchase), there has been a material breach by Genzyme of any representation, warranty, covenant or agreement set forth in the Merger Agreement (and such breach has not been cured or such condition has not been satisfied within 30 days after the receipt of notice thereof, or such breach is not reasonably capable of being cured or such condition is not reasonably capable of being satisfied within such period);



(g)

by SangStat, if other than due to an occurrence or circumstance that has resulted or would result in a failure to satisfy any condition set forth in Section 14 of this Offer to Purchase, the Purchaser shall have (1) failed to commence the Offer within 10 business days following the date of the Merger Agreement, (2) terminated the Offer without having accepted all Shares properly tendered for payment or (3) failed to accept any Shares properly tendered for payment pursuant to the Offer before the Termination Date, unless such action or inaction under clauses (1), (2) or (3) shall have been caused by or resulted from the failure of SangStat to perform, in any material respect, any of its covenants or agreements contained in the Merger Agreement, or the material breach by SangStat of any of its representations or warranties contained in the Merger Agreement;

29

(h)

by Genzyme, at any time before the purchase of Shares pursuant to the Offer, if the board of directors of SangStat shall have, in a manner adverse to Genzyme:



(1)

withdrawn, modified or changed its approval or recommendation of the Merger Agreement or the Offer, or publicly announced its intention to do so, or failed to recommend the Merger Agreement or the Offer;



(2)

recommended to SangStat's stockholders any proposal other than by Genzyme or the Purchaser in respect of an Acquisition Proposal (as defined below under "Alternative Acquisition Proposals"), or publicly announced its intention to do so;



(3)

made a Subsequent Determination (as defined below under "Alternative Acquisition Proposals");



(4)

adopted resolutions approving or otherwise authorizing or recommending an Acquisition Proposal that remain in effect and have not been rescinded; or



(5)

failed to recommend against, or taken a neutral position with respect to, a tender or exchange offer related to an Acquisition Proposal in any position taken pursuant to Rules 14d-9 and 14e-2 under the Exchange Act;



(i)

by Genzyme, at any time before the purchase of Shares pursuant to the Offer, if SangStat shall have materially violated or breached any of its obligations described below under "Alternative Acquisition Proposals" and such violation or breach has not been cured;



(j)

by SangStat, if SangStat has received a Superior Proposal (as defined below under "Alternative Acquisition Proposals") and Genzyme has not terminated the Merger Agreement by September 15, 2003; provided that SangStat has not materially breached its obligations described below under "Alternative Acquisition Proposals," and provided further that SangStat must pay Genzyme the Termination Fee (as defined below under "Fees and Expenses; Termination Fee") before it terminates the Merger Agreement pursuant to this clause; or



(k)

by either Genzyme or SangStat, if upon a vote at a duly held meeting to obtain the SangStat Stockholder Approval, the SangStat Stockholder Approval is not obtained; provided, that Genzyme may not terminate the Merger Agreement for this reason if the shares of SangStat common stock owned by Genzyme, the Purchaser or any of Genzyme's subsidiaries shall not have been voted in favor or obtaining SangStat Stockholder Approval.

        In the event that the Merger Agreement is terminated for any reason set forth above, the Merger Agreement shall become null and void and be of no further force or effect and there shall be no liability on the part of Genzyme, the Purchaser or SangStat, except for certain enumerated exceptions (including the termination fee described below under "Fees and Expenses; Termination Fee"), provided that such termination shall not relieve any of the parties to the Merger Agreement from liability for fraud or the intentional and willful breach of any of its representations, warranties, covenants or agreements set forth in the Merger Agreement. No termination of the Merger Agreement shall affect the obligations of Genzyme and SangStat described below under "Confidentiality Agreement."

        Alternative Acquisition Proposals.    The Merger Agreement requires SangStat and its Representatives (as defined below) to have ceased and caused to be terminated all existing solicitations, initiations, encouragements, discussions, negotiations and communications with any persons or entities with respect to any Acquisition Proposal (as defined below).

        In addition, the Merger Agreement provides that, from the date of the Merger Agreement until the earlier of the Effective Time or the termination of the Merger Agreement, except in the

30

circumstances described in the next paragraph, SangStat shall not, and shall not authorize or permit its Representatives to:

•

initiate, solicit or knowingly encourage, or knowingly take any action to facilitate the making of, any offer or proposal which constitutes or is reasonably likely to lead to any Acquisition Proposal;



•

enter into any agreement with respect to any Acquisition Proposal; or



•

engage in negotiations or discussions with, or provide any information or data to, any person or entity (other than Genzyme or any of its affiliates or representatives) relating to any Acquisition Proposal or grant any waiver or release under any standstill or other agreement.

        However, before the acceptance of Shares pursuant to the Offer, SangStat may furnish information concerning its business, properties or assets to any person or entity pursuant to a confidentiality agreement with terms no less favorable to SangStat than those contained in the confidentiality agreement between SangStat and Genzyme described below under "Confidentiality Agreement," and may negotiate and participate in discussions and negotiations with such person or entity concerning an Acquisition Proposal if, but only if, the Acquisition Proposal is a Superior Proposal (as defined below).

        In addition to the obligations of SangStat described in the preceding paragraphs, the Merger Agreement provides that SangStat shall promptly (and in any case within 24 hours) notify Genzyme (1) of any Superior Proposal, which notice shall include a copy of such Superior Proposal and (2) upon receipt of any inquiries, proposals or offers received by, any request for information from, or any discussions or negotiations sought to be initiated or continued with, either SangStat, or of its subsidiaries or Representatives concerning an Acquisition Proposal, or that would reasonably be expected to lead to an Acquisition Proposal, and disclose the identity of the other party and the material terms of such inquiry, offer, proposal or request and, in the case of written materials, provide copies of such materials. The Merger Agreement requires SangStat to keep Genzyme informed on a reasonably prompt basis (and, in any case, within 24 hours of any significant development) of the status and details (including amendments and proposed amendments) of any Superior Proposal or other inquiry, offer, proposal or request. If SangStat's board of directors determines that a Takeover Proposal (as defined below within the definition of Superior Proposal) is a Superior Proposal, SangStat must promptly notify Genzyme of such determination.

        The Merger Agreement further provides that, except as provided in the next paragraph, neither SangStat's board of directors, nor any committee of its board of directors, shall:

•

withdraw or modify, or propose to withdraw or modify, in a manner adverse to the Offer, the Merger or the other transactions contemplated by the Merger Agreement to Genzyme or the Purchaser, the approval or recommendation by SangStat's board of directors or any committee thereof of the Offer, the Merger Agreement or the Merger;



•

approve or recommend or propose to approve or recommend, any Acquisition Proposal; or



•

enter into any agreement with respect to any Acquisition Proposal.

        However, before the time of acceptance for payment of Shares in the Offer, SangStat's board of directors may (subject to the terms of this and the next two sentences) withdraw or modify its approval or recommendation of the Offer, the Merger Agreement or the Merger, or recommend a Superior Proposal, in either case at any time after (1), it has concluded in good faith, after receipt of advice from outside legal counsel, that the failure to take such action is reasonably likely to result in a breach of its fiduciary duties to SangStat's stockholders and (2) the fifth business day following SangStat's delivery to Genzyme of written notice advising Genzyme that SangStat's board of directors has received a Superior Proposal (which notice shall include a copy of such Superior Proposal and identify the person or entity making such Superior Proposal) and advising Genzyme that SangStat intends to

31

withdraw or modify its recommendation of the Offer, the Merger Agreement or the Merger or recommend a Superior Proposal (specifying which course of action SangStat intends to take) (a "Subsequent Determination"). After providing such notice, the Merger Agreement requires SangStat to provide to Genzyme two business days from the date of such notice to make such adjustments in the terms and conditions of the Merger Agreement as would enable SangStat to proceed with its original recommendation to stockholders without making a Subsequent Determination; provided, that any such adjustments shall be at the discretion of the parties at such time. Any withdrawal, modification or change of the recommendation of SangStat's board of directors, or recommendation or proposed recommendation of any Superior Proposal shall not change the approval of SangStat's board of directors for purposes of causing any state takeover statute or other state law to be inapplicable to the Offer and the Merger.

        The Merger Agreement also provides that the provisions described above do not prohibit SangStat or its board of directors from either (1) taking and disclosing to SangStat's stockholders its position with respect to any tender or exchange offer by a third party pursuant to Rules 14d-9 and 14e-2 promulgated under the Exchange Act, or (2) making such disclosure to SangStat's stockholders as in the good faith judgment of SangStat's board of directors, after receipt of advice from outside legal counsel, is required under applicable law and that the failure to make such disclosure is reasonably likely to cause SangStat's board of directors to violate its fiduciary duties to SangStat's stockholders under applicable law.

        "Acquisition Proposal" means any offer or proposal or potential offer or proposal relating to any transaction or proposed transaction or series of related transactions, other than the Offer or the Merger, involving:

•

any acquisition or purchase from SangStat by any person or "group" (as defined under Section 13(d) of the Exchange Act and the rules and regulations thereunder) of more than a 20% interest in the total outstanding voting securities of SangStat or any of its subsidiaries or any tender offer or exchange offer that if consummated would result in any person or "group" (as defined under Section 13(d) of the Exchange Act and the rules and regulations thereunder) beneficially owning 20% or more of the total outstanding voting securities of SangStat or any of its subsidiaries or any merger;



•

any consolidation, business combination, merger or similar transaction involving SangStat;



•

any sale, lease (other than in the ordinary course of business), exchange, transfer, license (other than in the ordinary course of business), acquisition or disposition of assets of SangStat or its subsidiaries (including for this purpose the outstanding equity securities of SangStat's subsidiaries) for consideration equal to 20% or more of the fair market value of all of the outstanding shares of SangStat's common stock on the date prior to the date hereof; or



•

any recapitalization, restructuring, liquidation or dissolution of SangStat.

"Representatives" means any of SangStat's officers, directors, employees, investment bankers, attorneys, accountants or other agents or those of its subsidiaries.

"Superior Proposal" means any Acquisition Proposal:

•

that provides for consideration to be received by the holders of all, but not less than all, of the issued and outstanding Shares (a "Takeover Proposal");



•

that is a bona fide written proposal that has been submitted to SangStat, in the absence of any violation by SangStat of its obligations described under "Alternative Acquisition Proposals," relating to any such Takeover Proposal which SangStat's board of directors determines in good faith (1) involves consideration to the holders of the Shares that is superior to the consideration offered pursuant to the Offer, (2) otherwise represents a superior transaction to the Offer and

32

the Merger, (3) is reasonably capable of being consummated by the Termination Date (as defined below under "Fees and Expenses; Termination Fee") and (4) which is not conditioned upon obtaining additional financing, or any regulatory approvals beyond or in addition to the applicable waiting periods under the HSR Act, the German AARC and any comparable provisions under any applicable pre-merger notification laws or regulations of other foreign jurisdictions; and

•

in response to which, in the good faith opinion of SangStat's board of directors after receipt of advice from outside legal counsel, providing information or access or engaging in discussions or negotiations is in the best interests of SangStat and its stockholders, and the failure to provide such information or access or to engage in such discussions or negotiations is reasonably likely to cause SangStat's board of directors to violate its fiduciary duties to SangStat's stockholders.

        Fees and Expenses; Termination Fee.    The Merger Agreement provides that except as described below, all fees, costs and expenses incurred in connection with the Merger Agreement and the transactions contemplated thereby shall be paid by the party incurring such expenses whether or not the Merger is consummated; provided, that Genzyme and SangStat shall share equally all fees and expenses, other than attorneys' and accountants fees and expenses, incurred in relation to the printing and filing with the SEC and mailing of the documents related to the Offer, the Schedule 14D-9 and the proxy or information statement, if necessary (including any preliminary materials related thereto), relating to the meeting of SangStat's stockholders to consider approval of the Merger Agreement and the Merger, and any amendments or supplements thereto, and the filing of any documents required under the HSR Act, the German AARC or any comparable provisions under any applicable pre-merger notification laws or regulations of other foreign jurisdictions.

        The Merger Agreement provides that SangStat will pay Genzyme a termination fee of $22,000,000 (the "Termination Fee") if Genzyme terminates the Merger Agreement pursuant to the provisions described in clauses (h) or (i) under "Termination of the Merger Agreement" above. In addition, if SangStat intends to terminate the Merger Agreement pursuant to the provisions described in clause (j) under "Termination of the Merger Agreement," it must pay Genzyme the Termination Fee prior to, and as a condition to, such termination. In addition, SangStat will pay Genzyme the Termination Fee if Genzyme terminates the Merger Agreement pursuant to the provisions described in clauses (c) or (d) under "Termination of the Merger Agreement," or pursuant to the provisions described in clause (e) under "Termination of the Merger Agreement" as a result of the failure to satisfy conditions (c) or (g) of the Offer described in Section 14 of this Offer to Purchase, and (1) at the time of the termination an Alternative Proposal has been publicly announced or communicated to SangStat's board of directors and not been withdrawn and (2) prior to August 4, 2004, SangStat enters into a written agreement, arrangement or understanding with respect to an Acquisition Proposal with any party other than Genzyme or its affiliates and consummates a transaction pursuant to such Acquisition Proposal.

        If the Merger Agreement is terminated in accordance with its terms by either SangStat or Genzyme in a manner that requires SangStat to pay Genzyme a Termination Fee, and Genzyme has received the Termination Fee, neither Genzyme nor the Purchaser can assert or pursue in any manner, directly or indirectly, (1) any claim or cause of action based in whole or in part upon alleged tortious or other interference with its rights under the Merger Agreement against any entity or person submitting an Acquisition Proposal, (2) any claim or cause of action against SangStat, its affiliates or any of their respective officers, directors, employees, stockholders, agents or representatives based in whole or in part upon a breach of any representation, warranty or covenant in the Merger Agreement, or (3) any claim or cause of action against SangStat, its affiliates or any of their respective officers, directors, employees, stockholders, agents or representatives based in whole or in part upon its or their receipt, consideration, recommendation or approval of an Acquisition Proposal for SangStat's exercise of its right of termination; provided, that the foregoing shall not relieve any party from liability for fraud or the intentional and willful breach of the Merger Agreement.

33

        Conduct of Business.    The Merger Agreement provides that during the period from the date of the Merger Agreement and continuing until the earlier of the termination of the Merger Agreement or the Effective Time, SangStat and each of its subsidiaries shall, except to the extent that Genzyme shall otherwise consent in writing and except as otherwise expressly provided in the Merger Agreement, carry on its business in the usual, regular and ordinary course, substantially the same manner as conducted prior to the execution of the Merger Agreement and in compliance in all material respects with all applicable laws and regulations, pay its debts and taxes when due subject to good faith disputes over such debts, and pay or perform other material obligations when due.

        Without limiting the generality of the foregoing, without the prior written consent of Genzyme, during the period from the date of the Merger Agreement and continuing until the earlier of the termination of the Merger Agreement pursuant to its terms or the Effective Time, the Merger Agreement provides that SangStat shall not do any of the following and shall not permit its subsidiaries to do any of the following, except as may be expressly contemplated or specifically permitted by the Merger Agreement:

•

waive any stock repurchase rights, accelerate, amend or change the period of exercisability of options or restricted stock, or reprice options granted under any employee, consultant, director or other stock plans or authorize cash payments in exchange for any options granted under any of such plans;



•

adopt a plan of complete or partial liquidation, dissolution, merger, consolidation, restructuring, recapitalization or other reorganization (other than the Merger);



•

grant any severance or termination pay to any officer, director or employee except pursuant to written agreements in effect, or policies existing, on the date hereof or adopt any new or amend any existing severance, retention or change in control plan;



•

transfer or license to any person or entity or otherwise extend, amend, modify, permit to lapse or fail to preserve any of SangStat's intellectual property rights material to SangStat's business as presently conducted or planned to be conducted, other than nonexclusive licenses in the ordinary course of business consistent with past practice or disclose to any person or entity who has not entered into a confidentiality agreement any trade secrets;



•

declare, set aside, or pay any dividends on or make any other distributions (whether in cash, stock, equity securities or property) in respect of any capital stock or split, combine or reclassify any capital stock or issue or authorize the issuance of any other securities in respect of, in lieu of or in substitution for any capital stock;



•

purchase, redeem or otherwise acquire, directly or indirectly, any shares of capital stock of SangStat or its subsidiaries, or any instrument or security that consists of a right to acquire such shares, except repurchases of unvested shares at cost in connection with the termination of the employment relationship with any employee pursuant to stock option or purchase agreements in effect on the date hereof;



•

issue, deliver, sell, authorize, pledge or otherwise encumber any shares of capital stock or any securities convertible into or exchangeable for shares of capital stock, or subscriptions, rights, warrants or options to acquire any shares of capital stock or any securities convertible into exchangeable for shares of capital stock, or enter into other agreements or commitments of any character obligating it to issue any such shares or convertible securities, other than the issuance, delivery and/or sale of shares of SangStat's common stock pursuant to the exercise of stock options or warrants therefor outstanding as of the date hereof in accordance with their present terms;

34

•

cause, permit or propose any amendments to its Certificate of Incorporation, Bylaws or other charter documents (or similar governing instruments of any of its subsidiaries);



•

acquire or agree to acquire by merging or consolidating with, or by purchasing any equity interest in or a portion of the assets of, or by any other manner, any business or any corporation, partnership, association or other business organization or division thereof; or otherwise acquire or agree to acquire any assets which are material, individually or in the aggregate, to the business of SangStat; or enter into or amend any material joint ventures, strategic partnerships or alliances;



•

sell, transfer, lease, license, mortgage, pledge, encumber or otherwise dispose of any properties or assets which are material, individually or in the aggregate, to the business of SangStat;



•

incur or assume any indebtedness for borrowed money or guarantee or otherwise become liable or responsible for (whether directly, contingently or otherwise) any such indebtedness of another person or entity, issue or sell any debt securities or options, warrants, calls or other rights to acquire any debt securities of SangStat other than (1) in connection with the financing of ordinary course trade payables consistent with past practice or (2) pursuant to existing credit facilities as in effect on the date hereof in the ordinary course of business;



•

adopt or amend any employee benefit plan or employee stock purchase or employee stock option plan, or enter into or amend any employment contract, consulting agreement or collective bargaining agreement (other than offer letters and letter agreements entered into in the ordinary course of business consistent with past practice and as may be required by applicable law), pay any special bonus or special remuneration to any director, officer or employee, or increase the salaries or wage rates or fringe benefits (including rights to severance or indemnification) of its directors, officers or employees other than to non-officer employees in the ordinary course of business consistent with past practice, or make any loans to any of its directors, officers or employees, agents or consultants, or make any change in its existing borrowing or lending arrangements for or on behalf of any of such person or entity pursuant to an employee benefit plan or otherwise;



•

pay or make any accrual or arrangement for payment of any pension, retirement allowance or other employee benefit pursuant to any existing plan, agreement or arrangement to any director or officer or pay or agree to pay or make any accrual or arrangement for payment to any officers or directors of SangStat or any of its subsidiaries of any amount relating to unused vacation days; adopt or pay, grant, issue, accelerate or accrue salary or other payments or benefits pursuant to any pension, profit-sharing, bonus, extra compensation, incentive, deferred compensation, stock purchase, stock option, stock appreciation right, group insurance, severance pay, retirement or other employee benefit plan, agreement or arrangement, or any employment or consulting agreement with or for the benefit of any SangStat or SangStat subsidiary director or officer, whether past or present, or amend in any material respect any such existing plan, agreement or arrangement in a manner inconsistent with the foregoing;



•

modify, amend or terminate any material contract or agreement to which SangStat or any subsidiary thereof is a party, including any joint venture agreement, or cancel any material debts or waive, release or assign any material rights or claims thereunder;



•

pay, discharge or satisfy any claims, liabilities or obligations (whether absolute, accrued, contingent or otherwise), other than the payment, discharge or satisfaction of any such claims, liabilities or obligations reflected or reserved against in, or contemplated by, the consolidated financial statements (or the notes thereto) of SangStat and its subsidiaries;



•

enter into any leases (including any amendments, extensions or replacements of leases existing as of the date hereof) or any purchase, acquisition licensing, distribution, collaboration,

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sponsorship, advertising or other similar contracts, agreements, or obligations material to SangStat;

•

permit any material insurance policy naming it as a beneficiary or a loss payee to be cancelled or terminated;



•

revalue any of its assets or make any change in accounting methods, principles or practices, except as required by GAAP;



•

make or change any election relating to taxes, adopt or change any accounting method relating to taxes, enter into any closing agreement relating to taxes, file any amended tax return, settle or consent to any claim or assessment relating to taxes, incur any obligation to make any payment of, or in respect of, any taxes, or agree to extend or waive the statutory period of limitations for the assessment or collection of taxes;



•

fail to notify and consult with Genzyme promptly (1) after receipt of any material communication from the United States Food and Drug Administration and before giving any material submission to the United States Food and Drug Administration, and (2) prior to making any material change to a study protocol, the addition of new trials, or a material change to the development timeline for any of its product candidates or programs;



•

authorize any single capital expenditure in excess of $200,000 or capital expenditure which in the aggregate exceed $500,000;



•

make any loans, advances or capital contributions to, or investments in, any other person or entity (other than to wholly-owned subsidiaries of SangStat or customary advances to employees for travel and business expenses in the ordinary course of business);



•

settle or compromise any pending or threatened suit, action or claim which is material or which relates to the transactions contemplated hereby;



•

effectuate a "plant closing" or "mass layoff," as those terms are defined in the Worker Adjustment and Retraining Notification Act of 1988, or effectuate any similar action under any foreign Law;



•

modify, amend or terminate, or waive, release or assign any material rights or claims with respect to any confidentiality agreement or non-competition agreement to which SangStat is a party;



•

commence any litigation or arbitration other than in accordance with past practice or settle any litigation or arbitration for money damages or other relief in excess of $100,000, or if as part of such settlement SangStat or any of its subsidiaries would agree to any restrictions on its operations, or which relates to the Merger Agreement, the Offer or the Merger; or



•

enter into any written agreement, contract, commitment or arrangement to do any of the foregoing, or authorize, recommend, propose or agree, in writing or otherwise, or announce an intention to do any of the foregoing.

        Board of Directors.    The Merger Agreement provides that promptly upon the first acceptance for payment of, and payment by the Purchaser for, any Shares which represent at least a majority of the Fully Diluted Shares pursuant to the Offer, the Purchaser shall be entitled to designate such number of directors on SangStat's board of directors as will give the Purchaser, subject to compliance with Section 14(f) of the Exchange Act, representation on SangStat's board of directors equal to at least that number of directors, rounded up to the next whole number, which is the product of (a) the total number of directors on SangStat's board of directors (giving effect to the directors elected pursuant to this sentence) multiplied by (b) the percentage that (i) such number of Shares so accepted for payment and paid for by the Purchaser plus the number of Shares otherwise owned by the Purchaser or any

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other subsidiary of Genzyme bears to (ii) the number of such Shares outstanding, and SangStat shall, at such time, cause the Purchaser's designees to be so elected; provided that in the event that the Purchaser's designees are appointed or elected to SangStat's board of directors, until the effective time of the merger, SangStat's board of directors shall have at least three directors who are directors on the date of the Merger Agreement and who are not officers of SangStat (the "Independent Directors"); and provided further that, in such event, if the number of Independent Directors is reduced below three for any reason whatsoever, any remaining Independent Directors (or Independent Director, if there is only one remaining) will be entitled to designate persons to fill such vacancies who will be deemed to be Independent Directors for purposes of the Merger Agreement or, if no Independent Directors then remain, the other directors will designate three persons to fill such vacancies who are not officers or affiliates of SangStat, Genzyme or the Purchaser, and such persons will be deemed to be Independent Directors for purposes of the Merger Agreement. At such time, SangStat shall, upon Genzyme's request, also cause persons elected or designated by Genzyme to constitute the same percentage (rounded up to the next whole number) as is on SangStat's board of directors of (1) each committee of SangStat's board of directors, (2) each board of directors (or similar body) of each of SangStat's subsidiaries, and (3) each committee (or similar body) of each such board, in each case only to the extent permitted by applicable law or the rules of any stock exchange on which SangStat's common stock is listed. Subject to applicable law, SangStat is required under the Merger Agreement to take all action requested by Genzyme necessary to effect any such election, including mailing to its stockholders the Information Statement containing the information required by Section 14(f) of the Exchange Act and Rule 14f-1 promulgated thereunder, and SangStat will make such mailing with the mailing of the Schedule 14D-9 (provided that the Purchaser has provided to SangStat on a timely basis all information required to be included in the Information Statement with respect to the Purchaser's designees). In connection with the foregoing, SangStat is required to promptly, at the option of the Purchaser, either increase the size of the board of directors of SangStat or obtain the resignation of such number of its current directors, or both, as is necessary to enable the Purchaser's designees to be elected or appointed to the board of directors of SangStat as provided above.

        Stock Options and Warrant.    At the Effective Time, each outstanding stock option, stock equivalent right or right to acquire Shares (each a "SangStat Option") granted under SangStat's 1996 Non-Employee Director Stock Option Plan and SangStat's 2002 Stock Option Plan (collectively, the "Option Plans"), whether or not then exercisable or vested, shall be (1) deemed to be one hundred percent (100%) vested and exercisable immediately prior to the Effective Time; and (2) immediately prior to the Effective Time, cancelled and, in consideration of such cancellation, Genzyme shall, or shall cause the surviving corporation in the Merger to, promptly following the Effective Time, pay to such holders of SangStat Options, an amount in respect thereof equal to the product of (a) the excess, if any, of the highest price per Share paid pursuant to the Offer over the exercise price of each such SangStat Option and (b) the number of unexercised Shares subject thereto, such payment, if any, to be net of applicable taxes required to be withheld.

        In addition, at the Effective Time, all repurchase rights in favor of SangStat with respect to Shares previously issued upon exercise of SangStat Options shall terminate automatically, and the unvested shares of Common Stock subject to those terminated rights shall immediately vest in full. The Merger Agreement provides that, at the Effective Time, the Option Plans shall terminate and all rights under any provision of any other plan, program or arrangement providing for the issuance or grant of any other interest in respect of the capital stock of SangStat or any of its subsidiaries shall be cancelled.

        Pursuant the Merger Agreement, SangStat shall use all reasonable efforts to effectuate the foregoing, including, but not limited to, sending out the requisite notices and obtaining all consents necessary to cash out and cancel all SangStat Options necessary to ensure that, after the Effective Time, no person shall have any right under the Option Plans, except as set forth herein. In addition, promptly after the commencement of the Offer, SangStat shall deliver to each holder of a warrant to

37

purchase SangStat common stock a notice regarding the Merger Agreement and the transactions contemplated thereby.

        Promissory Note.    The Merger Agreement provides that, at the Effective Time, if the $10 million Convertible Promissory Note due March 29, 2004 issued by SangStat in favor of Warburg Dillon Read LLC (the "SangStat Note") shall not have been converted by the holder thereof, the SangStat Note shall be assumed by Genzyme. The SangStat Note assumed by Genzyme shall have and be subject to, and convertible upon, the terms and conditions set forth in the SangStat Note, except that the SangStat Note shall be convertible only into the merger consideration receivable by a holder of that number of Shares into which the holder would have received had such holder converted the SangStat Note in full immediately prior to the Merger, in accordance with the terms of the SangStat Note. Promptly after the commencement of the Offer, Genzyme shall execute and deliver to the holder of the SangStat Note a supplemental agreement regarding the conversion of the SangStat Note following the Effective Time in accordance with the terms of the SangStat Note and SangStat shall deliver to the holder of the SangStat Note the officer's certificate and legal opinion contemplated by the terms of the SangStat Note.

        Employee Benefits.    The Merger Agreement provides that, following the Merger, Genzyme shall cause the surviving corporation in the Merger to provide that the employees of the surviving corporation are covered under Genzyme's then-current benefits plans, programs, policies and arrangements applicable to similarly situated employees of Genzyme. Years of service with SangStat and its subsidiaries prior to the Effective Time shall be treated as service with the surviving corporation in the Merger or Genzyme for all eligibility and vesting purposes and for purposes of vacation and severance pay accruals, except to the extent such treatment will result in a duplication of benefits.

        In addition, the Merger Agreement provides that, following the Merger, Genzyme shall take commercially reasonable efforts to cause to be waived all limitations as to preexisting condition limitations, exclusions and waiting periods with respect to participation and coverage requirements applicable to the employees of SangStat and its subsidiaries under any medical or dental benefit plans that such employees are eligible to participate in after the Effective Time, other than limitations, exclusions or waiting periods that are already in effect with respect to such employees and that have not been satisfied as of the Effective Time under any medical or dental plan maintained for such employees immediately prior to such Effective Time.

        The Merger Agreement also provides that SangStat shall, if and only if requested by Genzyme, terminate its 401(k) plan and its Nonqualifed Deferred Compensation Plan at least one day before the closing of the Merger.

        Indemnification and Insurance.    Genzyme has agreed in the Merger Agreement that at all times after the Effective Time, it shall indemnify, or shall cause the surviving corporation in the Merger and its subsidiaries to indemnify, each person who is now, or has been at any time prior to the date hereof, a director or officer of SangStat or of any of SangStat's subsidiaries, successors and assigns (collectively the "Indemnified Parties"), to the same extent and in the same manner as is now provided in the respective Certificates of Incorporation or Bylaws of SangStat and such subsidiaries and any indemnity agreement currently in effect, with respect to any claim, liability, loss, damage, cost or expense (whenever asserted or claimed) based in whole or in part on, or arising in whole or in part out of, any matter existing or occurring at or prior to the Effective Time. Genzyme understands and agrees that, prior to the Effective Time, SangStat intends to obtain a six year "tail" insurance policy that provides coverage substantially similar to the coverage provided under SangStat's directors and officers insurance policy in effect on the date of the Merger Agreement for the individuals who are directors and officers of SangStat on the date of the Merger Agreement for events occurring prior to the Effective Time; provided, without Genzyme's prior written consent (which consent shall not be unreasonably withheld or delayed), SangStat shall not pay more than $3,500,000 to purchase such policy; provided, that prior to

38

purchasing such policy, SangStat shall afford Genzyme the opportunity to purchase a substitute policy on terms not materially less favorable to SangStat and the Indemnified Parties.

        SangStat's Board of Directors shall take all action under the Indemnity Agreements between SangStat and certain of its current and former directors, officers and employees (1) to prevent the Merger Agreement and the transactions contemplated thereby from being deemed a "Change of Control" (as defined in the Indemnity Agreements) that, among other things, would require SangStat to seek advice from Independent Legal Counsel (as defined in the Indemnity Agreements) with respect to certain matters concerning the indemnification rights provided under the Indemnity Agreements and (2) to determine that the creation of any trust pursuant to Section 11(b) of such Indemnity Agreements, which would be intended to contain funds sufficient to satisfy certain expenses that may be required to be paid by SangStat under the Indemnity Agreements, would not be in the best interests of SangStat, all as more fully set forth in the Indemnity Agreements.

        Regulatory Filings; Reasonable Efforts.    The Merger Agreement provides that, as promptly as practicable after the date of the Merger Agreement, each of Genzyme, the Purchaser and SangStat shall make all filings, notices, petitions, statements, registrations, submissions of information, application or submission of other documents required by any Governmental Entity in connection with the Merger and the other transactions contemplated by the Merger agreement, including, without limitation: (1) Notification and Report Forms with the United States Federal Trade Commission and the Antitrust Division of the United States Department of Justice as required by the HSR Act, (2) filings required by the German AARC, (3) merger notification or control laws of any applicable jurisdiction, as agreed by the parties hereto, and (4) any filings required under the Securities Act, the Exchange Act, any applicable state or securities or "blue sky" laws and the securities laws of any foreign country, or any other applicable laws or rules and regulations of any Governmental Entity relating to the Merger.

        In addition, the Merger Agreement provides that each of Genzyme, the Purchaser, and SangStat shall promptly supply the other with any information which may be required in order to effectuate any filings or application pursuant to the previous paragraph. Except where prohibited by applicable laws and rules and regulations of any Governmental Entity, and subject to the confidentiality agreement between SangStat and Genzyme described below under "Confidentiality Agreement," each of SangStat and Genzyme shall consult with the other prior to taking a position with respect to any such filing, shall permit the other to review and discuss in advance, and consider in good faith the views of the other in connection with any analyses, appearances, presentations, memoranda, briefs, white papers, arguments, opinions and proposals before making or submitting any of the foregoing to any Governmental Entity by or on behalf of any party hereto in connection with any investigations or proceedings in connection with the Merger Agreement or the transactions contemplated hereby (including under any antitrust or fair trade laws), coordinate with the other in preparing and exchanging such information and promptly provide the other (or its counsel) with copies of all filings, presentations or submissions (and a summary of any oral presentations) made by such party with any Governmental Entity in connection with the Merger Agreement or the transactions contemplated hereby, provided that with respect to any such filing, presentation or submission, each of Genzyme and SangStat need not supply the other (or its counsel) with copies (or in case of oral presentations, a summary) to the extent that any law, treaty, rule or regulation of any Governmental Entity applicable to such party requires such party or its subsidiaries to restrict or prohibit access to any such properties or information.

        In addition, each of Genzyme, the Purchaser and SangStat will notify the others promptly upon the receipt of: (1) any comments from any officials of any Governmental Entity in connection with any filings made pursuant to the Merger Agreement and (2) any request by any officials of any Governmental Entity for amendments or supplements to any filings made pursuant to, or information provided to comply in all material respects with, any applicable laws and rules and regulations of any

39

Governmental Entity. Whenever any event occurs that is required to be set forth in an amendment or supplement to any filing made pursuant to these provisions of the Merger Agreement, Genzyme, the Purchaser or SangStat, as the case may be, will promptly inform the others of such occurrence and cooperate in filing with the applicable Governmental Entity such amendment or supplement.

        Each of the parties also agrees to use its reasonable efforts to take, or cause to be taken, all actions, and to do, or cause to be done, and to assist and cooperate with the other parties in doing, all things necessary, proper or advisable to consummate and make effective, in the most expeditious manner practicable, the Merger and the Offer, including complying in all material respects with all applicable laws and with all rules and regulations of any Governmental Entity and using its reasonable efforts to accomplish the following:

•

the taking of its reasonable acts necessary to cause all the conditions to the Merger described under "Conditions to the Merger" and all the conditions to the Offer described in Section 14 of this Offer to Purchase to be satisfied and to consummate and make effective the Merger and Offer;



•

the obtaining of all necessary actions or nonactions, waivers, consents, clearances, approvals, orders and authorizations from Governmental Entities and the making of all necessary registrations, declarations and filings (including registrations, declarations and filings with Governmental Entities, if any) and the taking of all reasonable steps as may be necessary to avoid any suit, claim, action, investigation or proceeding by any Governmental Entity;



•

the obtaining of all necessary consents, approvals or waivers from third parties;



•

the defending of any suits, claims, actions, investigations or proceedings, whether judicial or administrative, challenging the Merger Agreement or the consummation of the transactions contemplated by this agreement, including seeking to have any stay or temporary restraining order entered by any court or other Governmental Entity vacated or reversed; and



•

the execution or delivery of any additional instruments necessary to consummate the transactions contemplated by the Merger agreement, and to carry out fully the purposes of, the Merger Agreement.

        In connection with and without limiting the foregoing, SangStat and its board of directors shall, if any state takeover statute or similar statute or regulation is or becomes applicable to the Merger, the Offer or the Merger Agreement, use all reasonable efforts to ensure that the Merger and the Offer may be consummated as promptly as practicable on the terms contemplated by the Merger Agreement and otherwise to minimize the effect of such statute or regulation on the Merger, the Offer and the Merger Agreement. In case at any time after the Effective Time any further action is necessary or desirable to carry out the purposes of the Merger Agreement, the proper officers and directors of SangStat, Genzyme and the Purchaser shall use all reasonable efforts to take, or cause to be taken, all such necessary actions. Genzyme shall cause the Purchaser to fulfill all of the Purchaser's obligations under, and pursuant to, the Merger Agreement. Nothing in the Merger Agreement shall require Genzyme, the Purchaser or any other subsidiary of Genzyme to sell, hold separate, license or otherwise dispose of or conduct their business in a specified manner, or agree to sell, hold separate, license or otherwise dispose of or conduct their business in a specified manner, or permit the sale, holding separate, licensing or other disposition of, any assets of Genzyme, the Purchaser or any other subsidiary of Genzyme, whether as a condition to obtaining any approval from a Governmental Entity or any other person or for any other reason. Until the Merger Agreement is terminated in accordance with its terms, Genzyme shall have the right to participate in the defense of any action, suit or proceeding instituted against SangStat (or any of its directors or officers) before any court or governmental or regulatory body or threatened by any governmental or regulatory body, to restrain, modify or prevent

40

the consummation of the transactions contemplated by the Merger Agreement, or to seek damages or a discovery order in connection with such transactions.

        Notification.    The Merger Agreement requires each party to give prompt notice to the other parties of (1) the occurrence or non-occurrence of any event the occurrence or non-occurrence of which would cause any representation or warranty made by such party in the Merger Agreement to be untrue or inaccurate in any material respect at any time from the date of the Merger Agreement to the Effective Time, (2) any condition to the Offer set forth in Section 14 below that is unsatisfied in any material respect at any time from the date of the Merger Agreement to the date the Purchaser purchases Shares pursuant to the Offer (except to the extent it refers to a specific date), and (3) any material failure of such party or any of its representatives to comply with or satisfy any covenant, condition or agreement to be complied with or satisfied by it under the Merger Agreement; provided, that no such notification shall affect the representations, warranties, covenants or agreements of the parties, the conditions to the obligations of the parties under the Merger Agreement or the remedies available to the party receiving such notification.

        Representations and Warranties.    The Merger Agreement contains various customary representations and warranties, including representations relating to corporate organization, standing and power; capitalization; corporate authorizations; noncontravention; SEC filings; financial statements; absence of certain changes; absence of undisclosed liabilities; litigation; government authorizations; compliance with laws and applicable regulations; title to property; intellectual property; environmental matters; taxes; employee benefit plans; labor matters; insurance; brokers and finders fees; state takeover statutes; material contracts; actions taken under SangStat's Rights Agreement; products liability; absence of changes in commercial relationships; and brokers' and other fees.

        Certain representations and warranties in the Merger Agreement provide exceptions for items that are not reasonably likely to have a "Material Adverse Effect." For purposes of the Merger Agreement and the Offer, a "Material Adverse Effect" means with respect to any entity or group of entities, any event, change, condition or effect, event occurrence, states of facts or developments (any such item, an "Effect"), individually or together with other events, changes, conditions, effects, events, occurrences or states of facts or developments, that (1) is materially adverse, in the short term or the long term, to the condition (financial or otherwise), properties, assets (including intangible assets), liabilities, business, operations or results of operations of such entity and its subsidiaries, taken as a whole, or (2) would prevent or materially alter or delay any of the transactions contemplated by the Merger agreement; provided, that in no event shall any of the following be taken into account in determining whether there has been or will be a Material Adverse Effect on any entity: (A) any Effect (other than litigation challenging the acquisition by Genzyme or the Purchaser of any Shares under the Offer, seeking to delay, restrain or prohibit the making or consummation of the Offer or the Merger or the performance of any of the other transactions contemplated by the Merger Agreement or seeking to obtain from SangStat, Genzyme or the Purchaser any damages that are material in relation to SangStat and SangStat's subsidiaries taken as a whole) primarily resulting from compliance with the terms and conditions of the Merger Agreement; provided, that no inference may be drawn hereby by any such litigation, (B) any Effect primarily resulting from the announcement or pendency of the Offer or the Merger, (C) any change in such entity's stock price or trading volume, (D) any Effect that results from changes affecting the industry in which such entity operates generally or the United States economy generally, without a disproportionate impact on such entity, (E) any Effect that results from changes affecting general worldwide economic or capital market conditions, without a disproportionate impact on such entity, or (F) after September 30, 2003, any failure by such entity to meet published revenue or earnings projections or any internal projections for any period ending (or for which earnings are released) on or after August 4, 2003 and prior to the closing date of the Merger, provided that no inference may be drawn hereby by any failure to meet a projection prior to September 30, 2003.

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        Certain representations and warranties of SangStat are made to the "Knowledge" of SangStat. For purposes of the Merger Agreement, the term "Knowledge" means, with respect to any matter in question, that any of Richard D. Murdock, Stephen G. Dance, Raymond J. Tesi, Raysam S. Prasad, Steve Aselage, Ralph Levy and Adrian Arima has actual knowledge of such matter. With respect to certain representations and warranties related to SangStat's employee benefit plans, the above list of individuals also includes Marlene Perry.

        Amendments and Modifications.    The Merger Agreement may be amended, modified and supplemented in any and all respects, whether before or after any vote of the stockholders of SangStat contemplated by the Merger Agreement, by written agreement of the parties, by action taken by their respective boards of directors, but, after the purchase of Shares pursuant to the Offer, no amendment shall be made which decreases the consideration to be paid in the Merger and, after the approval of the Merger Agreement by the stockholders, no amendment shall be made which by law requires further approval by such stockholders without obtaining such further approval.

        Extensions and Waivers.    At any time prior to the Effective Time, any party to the Merger Agreement may, to the extent legally allowed, (1) extend the time for the performance of any of the obligations or other acts of the other parties in the Merger Agreement, (2) waive any inaccuracies in the representations and warranties made to such party contained in the Merger Agreement or in any document delivered pursuant to the Merger Agreement, and (3) waive compliance with any of the agreements or conditions for the benefit of such party contained in the Merger Agreement; provided, that Genzyme and the Purchaser cannot waive the Minimum Condition without the consent of SangStat's board of directors.

Confidentiality Agreement

        Genzyme and SangStat entered into a Confidentiality Agreement on June 12, 2003, which was amended by the Merger Agreement. Pursuant to the Confidentiality Agreement, SangStat and Genzyme agreed to keep confidential certain information provided by SangStat or its representatives. The Merger Agreement provides that the Confidentiality Agreement remains in effect and that certain information exchanged pursuant to the Merger Agreement will be subject to the Confidentiality Agreement. The Merger Agreement amends the Confidentiality Agreement to permit Genzyme and SangStat to disclose the U.S. tax treatment and tax structure of the Offer and the Merger.

Plans for SangStat

        After the purchase of Shares by the Purchaser pursuant to the Offer, Genzyme may appoint its representatives to SangStat's board of directors in proportion to its ownership of the outstanding Shares, as described above under "Board of Directors." Following completion of the Offer and the Merger, Genzyme intends to operate SangStat as a subsidiary of Genzyme under the direction of Genzyme's management. The Purchaser expects that, initially following the consummation of the Offer, the products currently marketed by SangStat will continue to be commercialized, both in the United States and elsewhere, and that Genzyme will invest in additional studies intended to broaden their use. Genzyme also expects to continue, together with strategic partners, SangStat's development programs in human polyclonal antibodies and its RDP technology. Genzyme and the Purchaser will continue to review various possible business strategies for SangStat, should they acquire control of SangStat, that may ultimately involve, among other things, changes in SangStat's business, operations, capitalization and management. Accordingly, Genzyme and the Purchaser reserve the right to change their plans and intentions at any time, as they deem appropriate.

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Appraisal Rights

        The holders of the Shares do not have appraisal rights as a result of the Offer. However, if the Merger is consummated, holders of the Shares (that did not tender their Shares in the Offer) at the Effective Time will have certain rights pursuant to the provisions of Section 262 of the DGCL (the "Appraisal Provisions") to dissent and demand appraisal of their Shares. Under the Appraisal Provisions, dissenting stockholders who comply with the applicable statutory procedures will be entitled to demand payment of fair value for their Shares. If a stockholder and the surviving corporation in the Merger do not agree on such fair value, the stockholder will have the right to a judicial determination of fair value of such stockholder's Shares (exclusive of any element of value arising from the accomplishment or expectation of the Merger) and to receive payment of such fair value in cash, together with any interest as determined by the court. Any such judicial determination of the fair value of Shares could be based upon factors other than, or in addition to, the price per Share to be paid in the Merger or the market value of the Shares. The value so determined could be more or less than the price per Share to be paid in the Merger.

        The foregoing summary of the Appraisal Provisions does not purport to be complete and is qualified in its entirety by reference to the Appraisal Provisions. A complete text of Section 262 of the DGCL is set forth as Annex II hereto. Failure to follow the steps required by the Appraisal Provisions for perfecting appraisal rights may result in the loss of such rights.

Going-Private Transactions

        Rule 13e-3 under the Exchange Act is applicable to certain "going private" transactions. Genzyme and the Purchaser do not believe that Rule 13e-3 will be applicable to the Merger unless the Merger is consummated more than one year after the termination of the Offer. If applicable, Rule 13e-3 requires, among other things, that certain financial information concerning the fairness of the Merger and the consideration offered to minority stockholders in the Merger be filed with the SEC and disclosed to stockholders prior to the consummation of the Merger.

13.    Dividends and Distributions

        As discussed in Section 12, the Merger Agreement provides that from the date of the Merger Agreement, until the earliest to occur of the termination of the Merger Agreement or the Effective Time, without the prior written consent of Genzyme, SangStat may not declare, set aside or pay any dividends on, or make any other distributions in respect of, any of its capital stock.

14.    Certain Conditions of the Offer

        The Merger Agreement provides that the Purchaser shall not be required to accept for payment or, subject to any applicable rules and regulations of the SEC, including Rule 14e-l(c) under the Exchange Act (relating to the Purchaser's obligation to pay for or return tendered Shares promptly after termination or withdrawal of the Offer), pay for, and may delay the acceptance for payment of or, subject to the restriction referred to above, the payment for, any validly tendered Shares if, there shall not have been validly tendered and not withdrawn prior to the expiration of the Offer that number of Shares which, together with that number of Shares owned by Genzyme, the Purchaser and Genzyme's other subsidiaries, would represent a majority of the Fully Diluted Shares. For the purpose of the Merger Agreement the term "Fully Diluted Shares" means all outstanding securities entitled generally to vote in the election of directors of SangStat on a fully diluted basis, assuming the exercise or conversion of all vested options, rights and securities exercisable or convertible into such voting securities. Furthermore, notwithstanding any other provisions of the Offer, the Purchaser shall not be required to accept for payment or pay for any validly tendered shares if, on or before the date the offer expires (including any permitted extensions of such date) (1) the applicable waiting period under

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the HSR Act has not expired or been terminated; (2) the applicable waiting period under the German AARC has not expired or been terminated, (3) any clearances or approvals as may be required under any applicable pre-merger notification laws or regulations of other foreign jurisdictions have not been obtained, or (4) any of the following events shall occur, or shall be deemed by Purchaser to have occurred, and be continuing:

(a)

there shall be threatened in writing or pending any suit, action or proceeding by any Governmental Entity or any third party against the Purchaser, Genzyme, SangStat or any SangStat subsidiary:



(i)

seeking to prohibit or impose any material limitations on Genzyme's or the Purchaser's ownership or operation (or that of any of their respective subsidiaries or affiliates) of all or any material portion of their or SangStat's or SangStat's subsidiaries' businesses or assets, taken as a whole, or to compel Genzyme or the Purchaser or their respective subsidiaries or affiliates to dispose of or hold separate any material portion of the business or assets of SangStat or Genzyme or their respective subsidiaries;



(ii)

challenging the acquisition by Genzyme or the Purchaser of any Shares under the Offer, seeking to delay, restrain or prohibit the making or consummation of the Offer or the Merger or the performance of any of the other transactions contemplated by the Merger agreement, or seeking to obtain from SangStat, Genzyme or the Purchaser any damages that are material in relation to SangStat and SangStat's subsidiaries taken as a whole;



(iii)

seeking to impose material limitations on the ability of the Purchaser, or render the Purchaser unable, to accept for payment, pay for or purchase some or all of the Shares pursuant to the Offer or the Merger;



(iv)

seeking to impose material limitations on the ability of the Purchaser or Genzyme effectively to exercise full rights of ownership of the Shares, including, without limitation, the right to vote the Shares purchased by it on all matters properly presented to SangStat's stockholders; or



(v)

seeking to require divestiture by Genzyme or any of its subsidiaries or affiliates of any Shares;



(b)

there shall be any statute, rule, regulation, judgment, order or injunction enacted, entered, enforced, promulgated or deemed applicable, pursuant to an authoritative interpretation by or on behalf of a Government Entity, to the Offer, the Merger or any other transaction contemplated by the Merger Agreement, or any other action shall be taken by any Governmental Entity, that is reasonably likely to result, directly or indirectly, in any of the consequences referred to in clauses (i) through (v) of paragraph (a) above;



(c)

any of the representations and warranties of SangStat contained in the Merger Agreement shall not be true and correct in all material respects (other than representations and warranties qualified by materiality or Material Adverse Effect, which shall be true and correct in all respects) as of the date of the Merger Agreement and as of the date of any scheduled expiration of the Offer, except for representations and warranties that relate to a specific date or time (which need only be true and correct in all material respects as of such date or time) and except for those representations and warranties set forth in Section 3.2—Capitalization of the Merger Agreement (which shall be true and correct in all respects, other than de minimis variations);



(d)

since the date of the Merger Agreement, there shall have occurred any events or changes which have had, which are deemed to have had, or which are reasonably likely to have or constitute, individually or in the aggregate, a Material Adverse Effect on SangStat;

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(e)

SangStat board of directors or any committee thereof shall have:



(i)

withdrawn, or modified or changed in a manner adverse to the transactions contemplated by the Merger agreement, to Genzyme or to the Purchaser (including by amendment of the Schedule 14D-9), its recommendation of the Offer, the Merger Agreement, or the Merger or shall have failed to make such favorable recommendation;



(ii)

approved or recommended to its stockholders any Acquisition Proposal or entered into or publicly announced its intention to enter into any agreement or agreement in principle with respect to any Acquisition Proposal;



(iii)

resolved or publicly proposed to do any of the foregoing; or



(iv)

taken a neutral position or made no recommendation with respect to an Acquisition Proposal (other than by Genzyme or the Purchaser) after a reasonable amount of time (and in no event more than five (5) business days following receipt thereof) has elapsed for SangStat board of directors or any committee thereof to review and make a recommendation with respect thereto;



(f)

any person or group (as defined in Section 13(d)(3) of the Exchange Act) other than Genzyme or any of its subsidiaries shall have become the beneficial owner (defined in Rule 13(d)(3) promulgated under the Exchange Act) of more than twenty percent (20%) of the outstanding Shares or shall have acquired, directly or indirectly, more than twenty percent (20%) of the assets of SangStat and its subsidiaries;



(g)

SangStat shall have breached or failed, in any material respect, to perform or to comply with any material agreement, obligation or covenant to be performed or complied with by it under the Merger Agreement;



(h)

The Purchaser shall have failed to receive a certificate executed by SangStat's Chief Executive Officer or President on behalf of SangStat, dated as of the scheduled expiration of the Offer, to the effect that the conditions set forth in the foregoing clauses (c), (d), (e), (f) and (g) have not occurred;



(i)

the Merger Agreement shall have been terminated in accordance with its terms;



(j)

all consents, permits and approvals of Governmental Authorities listed in Section 3.3 of the disclosure letter delivered by SangStat to Genzyme and the Purchaser shall not have been obtained; or



(k)

there shall have occurred and be continuing (1) a declaration by a Governmental Entity of a banking moratorium or any suspension of payments in respect of banks in the United States or (2) a commencement of a war, armed hostilities or other international or national calamity directly or indirectly involving the United States, which precludes Genzyme's or the Purchaser's consummation of the transactions contemplated by the Merger agreement.

        The foregoing conditions are for the sole benefit of Genzyme and the Purchaser, may be asserted by Genzyme or the Purchaser regardless of the circumstances giving rise to such condition, and may be waived by Genzyme or the Purchaser in whole or in part at any time and from time to time prior to the expiration of the Offer and in the sole discretion of Genzyme or the Purchaser, subject in each case to the terms of the Merger Agreement. Genzyme and the Purchaser cannot waive the Minimum Condition without the consent of SangStat's board of directors. The failure by Genzyme or the Purchaser at any time to exercise any of the foregoing rights shall not be deemed a waiver of any such right and, each such right shall be deemed an ongoing right which may be asserted at any time and from time to time prior to the expiration of the Offer.

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        The Merger Agreement provides that the Purchaser may, without the consent of the SangStat, (1) extend the Offer beyond the initial expiration date if, at any scheduled (or extended) expiration of the Offer, any of the conditions to the Purchaser's obligation to accept Shares for payment, shall not be satisfied or waived, (2) extend the Offer for any period required by any rule, regulation or interpretation of the SEC, or the staff thereof, applicable to the Offer, or (3) extend (or re-extend) the Offer for an aggregate period of not more than 20 business days (taking into account all such extensions and re-extensions), beyond the latest applicable date that would otherwise be permitted under clause (1) or (2) of this sentence, if, as of such date, all of the conditions to the Purchaser's obligations to accept for payment Shares are satisfied or waived, but there shall not have been validly tendered and not withdrawn pursuant to the Offer that number of Shares necessary to permit the Merger to be effected without a meeting of the SangStat's stockholders in accordance with the DGCL. In addition, the Purchaser may provide a "subsequent offering period" in accordance with Rule 14d-11 under the Exchange Act.

15.    Certain Legal Matters

        Except as described in this Section 15, based on a review of publicly available filings made by SangStat with the SEC and other publicly available information concerning SangStat and discussions of representatives of Genzyme with representatives of SangStat, none of Genzyme, the Purchaser or SangStat is aware of any license or regulatory permit that appears to be material to the business of SangStat and its subsidiaries, taken as a whole, that might be adversely affected by the Purchaser's acquisition of the Shares (and the indirect acquisition of the stock of SangStat's subsidiaries) as contemplated herein or of any approval or other action by any Governmental Entity that would be required or desirable for the acquisition or ownership of the Shares by the Purchaser as contemplated herein. Should any such approval or other action be required or desirable, Genzyme and the Purchaser currently contemplate that such approval or other action will be sought, except as described below under "State Takeover Laws." There can be no assurance that any such approval or other action, if needed, would be obtained or would be obtained without substantial conditions or that failure to obtain any such approval or other action might not result in consequences adverse to SangStat's business or that certain parts of SangStat's business might not have to be disposed of if such approvals were not obtained or such other actions were not taken or in order to obtain any such approval or other action. If certain types of adverse actions are taken with respect to the matters discussed below, the Purchaser could, subject to the terms and conditions of the Merger Agreement, decline to accept for payment or pay for any Shares tendered. See Section 14 for a description of certain conditions to the Offer.

        State Takeover Laws.    A number of states throughout the United States have enacted takeover statutes that purport, in varying degrees, to be applicable to attempts to acquire securities of corporations that are incorporated or have assets, stockholders, executive offices or places of business in such states. In Edgar v. MITE Corp., the Supreme Court of the United States held that the Illinois Business Takeover Act, which involved state securities laws that made the takeover of certain corporations more difficult, imposed a substantial burden on interstate commerce and therefore was unconstitutional. In CTS Corp. v. Dynamics Corp. of America, however, the Supreme Court of the United States held that a state may, as a matter of corporate law and, in particular, those laws concerning corporate governance, constitutionally disqualify a potential acquiror from voting on the affairs of a target corporation without prior approval of the remaining stockholders, provided that such laws were applicable only under certain conditions. Subsequently, a number of U.S. federal courts ruled that various state takeover statutes were unconstitutional insofar as they apply to corporations incorporated outside the state of enactment.

        Section 203 of the DGCL, in general, prohibits a Delaware corporation such as SangStat from engaging in a "Business Combination" (defined as a variety of transactions, including mergers) with an "Interested Stockholder" (defined generally as a person that is the beneficial owner of 15% or more of

46

a corporation's outstanding voting stock) for a period of three years following the time that such person became an Interested Stockholder unless: (a) prior to the time such person became an Interested Stockholder, the board of directors of the corporation approved either the business combination or the transaction that resulted in the stockholder becoming an Interested Stockholder; (b) upon consummation of the transaction that resulted in the stockholder becoming an Interested Stockholder, the Interested Stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the voting stock outstanding (but not the outstanding voting stock owned by the Interested Stockholder) to those shares owned by (i) directors who are also officers of the corporation and (ii) employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject the plan will be tendered in a tender or exchange offer; or (c) at or subsequent to the time such person became an Interested Stockholder, the Business Combination is approved by the board of directors of the corporation and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of the holders of a least 66²/3% of the outstanding voting stock of the corporation not owned by the Interested Stockholder. The foregoing description of Section 203 does not purport to be complete and is qualified in its entirety by reference to the provisions of Section 203.

        SangStat's board of directors has approved the Offer, the Merger and the Merger Agreement for purpose of Section 203 of the DGCL.

        Based on information supplied by SangStat and the approval of the Merger Agreement, the Merger and the Offer by the board of directors of SangStat, the Purchaser does not believe that any state takeover statutes or similar laws purport to apply to the Offer or the Merger. Except as described herein, neither Genzyme nor the Purchaser has currently complied with any state takeover statute or regulation. The Purchaser reserves the right to challenge the applicability or validity of any state law purportedly applicable to the Offer or the Merger and nothing in this Offer to Purchase or any action taken in connection with the Offer or the Merger is intended as a waiver of such right. If it is asserted that any state takeover statute is applicable to the Offer or the Merger and an appropriate court does not determine that it is inapplicable or invalid as applied to the Offer or the Merger, the Purchaser might be required to file certain information with, or to receive approvals from, the relevant state authorities, and the Purchaser might be unable to accept for payment or pay for Shares tendered pursuant to the Offer, or be delayed in consummating the Offer or the Merger. In such case, the Purchaser may not be obligated to accept payment or pay for any Shares tendered pursuant to the Offer. See Section 14 of this Offer to Purchase.

Antitrust

        United States.    Genzyme and SangStat are each required to file a Notification and Report Form with respect to the Offer under the HSR Act prior to completing the Offer. Under the provisions of the HSR Act applicable to the Offer, the acquisition of Shares pursuant to the Offer may be consummated after the expiration of a 15-calendar day waiting period commenced by the filing of a Notification and Report Form with respect to the Offer, unless Genzyme receives a request for additional information or documentary material from the Antitrust Division of the Department of Justice or the Federal Trade Commission (the "FTC") or unless early termination of the waiting period is granted. Genzyme and SangStat are in the process of preparing such filings. If, within the initial 15-day waiting period, either the Antitrust Division or the FTC requests additional information from Genzyme concerning the Offer, the waiting period will be extended and would expire at 11:59 p.m., New York City time, on the tenth calendar day after the date of substantial compliance by Genzyme with such request. Only one extension of the waiting period pursuant to a request for additional information is authorized by the HSR Act. Thereafter, such waiting period may be extended only by court order or with the consent of Genzyme. In practice, complying with a request for additional

47

information or material can take a significant amount of time. In addition, if the Antitrust Division or the FTC raises substantive issues in connection with a proposed transaction, the parties frequently engage in negotiations with the relevant governmental agency concerning possible means of addressing those issues and may agree to delay consummation of the transaction while such negotiations continue. Expiration or termination of the applicable waiting period under the HSR Act is a condition to the Purchaser's obligation to accept for payment and pay for Shares tendered pursuant to the Offer.

        The Merger will not require an additional filing under the HSR Act if the Purchaser owns 50% or more of the outstanding Shares at the time of the Merger or if the Merger occurs within one year after the HSR Act waiting period applicable to the Offer expires or is terminated.

        The Antitrust Division and the FTC frequently scrutinize the legality under the antitrust laws of transactions such as the Purchaser's proposed acquisition of SangStat. At any time before or after the Purchaser's acquisition of Shares pursuant to the Offer, the Antitrust Division or the FTC could take such action under the antitrust laws as it deems necessary or desirable in the public interest, including seeking to enjoin the purchase of Shares pursuant to the Offer or the consummation of the Merger or seeking the divestiture of Shares acquired by the Purchaser or the divestiture of substantial assets of SangStat or its subsidiaries or Genzyme or its subsidiaries. Private parties, including state Attorneys General, may also bring legal action under the antitrust laws under certain circumstances. There can be no assurance that a challenge to the Offer on antitrust grounds will not be made or, if such a challenge is made, of the result thereof.

        Germany.    Under the provisions of the German AARC applicable to the Offer, the acquisition of the Shares pursuant to the Offer may be consummated one month after Genzyme and SangStat submit a joint pre-merger notification to Germany's Federal Cartel Office (the "FCO") with respect to the Offer (a "first stage investigation"), unless the FCO determines to subject the Offer to further investigation (a "second stage investigation") or unless the FCO otherwise consents. Genzyme and SangStat are in the process of preparing their joint pre-merger notification to the FCO.

        Where it is clear to the FCO that a transaction will not pose substantive competition problems in Germany, the FCO generally issues a clearance letter during the first stage investigation. This first stage clearance is not subject to appeal by third parties. In connection with a second stage investigation, however, the FCO must render a reasoned clearance decision and such decision may be appealed by any interested third parties that have been admitted to the proceedings. The FCO may take up to four months (first and second stage investigations taken together) after a pre-merger notification is submitted to investigate and possibly challenge a transaction, and may take additional time to do so if the relevant parties consent to such extension. There can be no assurance that a challenge to the Offer under German law on competition or other grounds will not be made or, if such a challenge is made, of the results thereof.

        Expiration or termination of the applicable waiting period under the German AARC is a condition to the Purchaser's obligation to accept for payment and pay for Shares tendered pursuant to the Offer.

        Other Foreign Jurisdictions.    It may be necessary to make additional filings relating to the acquisition of the Shares pursuant to the Offer or the Merger with governmental entities in other foreign jurisdictions. Genzyme and SangStat are reviewing whether any such filings are required in connection with the Offer or the Merger and intend to make such filings promptly to the extext required. There can be no assurance that such governmental entities will not challenge the acquisition of the Shares on competition or other grounds or, if such a challenge is made, of the results thereof.

        Litigation.    On August 7, 2003, Rocco Pignone filed a complaint in the California Superior Court, County of Alameda against SangStat and Jean-Jacques Bienaime, Fredric J. Feldman, Corinne H. Lyle, Richard D. Murdock, Andrew J. Perlman, Hollings C. Renton III and certain unnamed individuals (collectively, the "SangStat Parties"). The action was brought individually and as a putative class action

48

on behalf of all holders of Shares other than the SangStat Parties and their affiliates. The complaint alleges, among other matters, that the SangStat Parties breached their fiduciary duties to holders of Shares by failing to maximize shareholder value in connection with the proposed Offer and failing to disclose certain information to holders of Shares. The complaint seeks to enjoin the Offer and to have the Merger Agreement declared unlawful. SangStat has informed Genzyme that it believes the allegations contained in the complaint to be entirely without merit and intends to defend against the claims vigorously.

        The foregoing description of the complaint is qualified in its entirety by reference to the complaint itself, which is an exhibit to the Tender Offer Statement on Schedule TO that Genzyme and the Purchaser have filed with the SEC. Copies of the Tender Offer Statement on Schedule TO together with all exhibits thereto, including the complaint, may be obtained and examined as set forth in Section 9 "Certain Information Concerning Genzyme and the Purchaser."

        Absence of any pending third party actions against SangStat seeking to delay or prohibit the consummation of the Offer or the Merger is a condition to the Purchaser's obligation to accept for payment and pay for Shares tendered pursuant to the Offer.

16.    Fees and Expenses

        Credit Suisse First Boston is acting as financial advisor to Genzyme and as Dealer Manager in connection with the Offer and will receive customary fees for its services in connection with its engagement. Genzyme has agreed to reimburse Credit Suisse First Boston for certain expenses, including the fees and expenses of its legal counsel and other advisors, and to indemnify Credit Suisse First Boston against certain liabilities in connection with its engagement, including certain liabilities under the U.S. federal securities laws. In the ordinary course of business, Credit Suisse First Boston and its affiliates may actively trade Shares for their own account and for the accounts of customers, and accordingly, may at any time hold a long or short position in the Shares.

        Genzyme and the Purchaser have retained Innisfree M&A Incorporated to act as the Information Agent and American Stock Transfer & Trust Company to serve as the Depositary in connection with the Offer. The Information Agent and the Depositary each will receive reasonable and customary compensation for their services, be reimbursed for certain reasonable out-of-pocket expenses and be indemnified against certain liabilities and expenses in connection therewith, including certain liabilities and expenses under the U.S. federal securities laws.

        Neither Genzyme nor the Purchaser will pay any other fees or commissions to any broker or dealer or other person for soliciting tenders of Shares pursuant to the Offer. Brokers, dealers, banks, trust companies and other members will be reimbursed by the Purchaser upon request for customary mailing and handling expenses incurred by them in forwarding material to their customers.

17.    Miscellaneous

        The Offer is not being made to (nor will tenders be accepted from or on behalf of) holders of Shares in any jurisdiction in which the making of the Offer or the acceptance thereof would not be in compliance with the laws of such jurisdiction. Neither Genzyme nor the Purchaser is aware of any jurisdiction in which the making of the Offer or the acceptance thereof would not be in compliance with the laws of such jurisdiction. To the extent Genzyme or the Purchaser becomes aware of any state law that would limit the class of offerees in the Offer, the Purchaser will amend the Offer and, depending on the timing of such amendment, if any, will extend the Offer to provide adequate dissemination of such information to holders of Shares prior to the expiration of the Offer.

Neither Genzyme nor the Purchaser has authorized any person to give any information or to make any representation on behalf of Genzyme or the Purchaser not contained in this Offer to

49

Purchase or in the Letter of Transmittal and, if given or made, such information or representation must not be relied upon as having been authorized.

        Genzyme and the Purchaser have filed with the SEC the Tender Offer Statement on Schedule TO pursuant to Rule 14d-3 under the Exchange Act, together with exhibits, furnishing certain additional information with respect to the Offer, and may file amendments thereto. In addition, SangStat has filed the Schedule 14D-9 pursuant to Rule 14d-9 under the Exchange Act, together with exhibits, setting forth its recommendation with respect to the Offer and the reasons for such recommendation and furnishing certain additional related information. Such Schedules and any amendments thereto, including exhibits, should be available for inspection and copies should be obtainable in the manner set forth in Section 8 and Section 9 of this Offer to Purchase.

SWIFT STARBOARD CORPORATION

August 13, 2003

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ANNEX I

Directors and Executive Officers of Genzyme and the Purchaser

        The names of the directors and executive officers of Genzyme Corporation and Swift Starboard Corporation and their present principal occupations or employment and material employment history during the past five years are set forth below. Unless otherwise indicated, each director and executive officer has been so employed for a period in excess of five years. Unless otherwise indicated, each individual is a citizen of the United States, his business address is One Kendall Square, Cambridge, MA 02139, and his business telephone number is (617) 252-7500.

Genzyme Corporation

Directors

Henri A. Termeer, Chairman of the Board, President and Chief Executive Officer
Director since 1983

        Mr. Termeer has served as President of Genzyme Corporation (One Kendall Square, Cambridge, Massachusetts 02139) since October 1983, Chief Executive Officer since December 1985 and Chairman of the Board since May 1988. Mr. Termeer is also a director of ABIOMED, Inc. and a trustee of Hambrecht & Quist Healthcare Investors and of Hambrecht & Quist Life Sciences Investors.

Constantine E. Anagnostopoulos, Ph.D.
Director since 1986

        Dr. Anagnostopoulos is Managing General Partner of Gateway Associates (8000 Maryland Avenue, Suite 1190, Clayton, Missouri 63105), which is the general partner of Gateway Venture Partners III, L.P., a venture capital partnership. He is a retired corporate executive of Monsanto Company, and is also a director of Dyax Corp. and Deltagen, Inc.

Douglas A. Berthiaume
Director since 1988

        Mr. Berthiaume is Chairman, President and Chief Executive Officer of Waters Corporation (34 Maple Street, Milford, Massachusetts 01757), a high technology manufacturer of high performance liquid chromatography instrumentation and consumables, and thermal analysis and mass spectrometry products used for analysis and purification. From November 1990 to August 1994, he was President of the Waters Division of Millipore Corporation.

Henry E. Blair
Director since 1981

        Mr. Blair is the Chairman and Chief Executive Officer of Dyax Corp. (300 Technology Square, Cambridge, Massachusetts 02139), a public bioseparation, pharmaceutical discovery and development company. He has served as a director and officer of Dyax since its formation in 1989. Prior to January 1990, Mr. Blair was Senior Vice President, Scientific Affairs of Genzyme Corporation from the time he co-founded Genzyme in 1981. Mr. Blair is a director of Esperion Therapeutics, Inc. and is a member of the board of overseers at Tufts University School of Medicine, the Lahey Hitchcock Clinic and the Center for Blood Research.

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Robert J. Carpenter
Director since 1994

        Mr. Carpenter is Chairman, President and Chief Executive Officer of Peptimmune, Inc. (64 Sidney Street, Suite 380, Cambridge, Massachusetts 02139), which develops immunotherapies for treating auto-immune and allergy diseases. He is also President of Boston Medical Investors, Inc., a privately held company he formed in 1994 that invests in early stage health care companies. From November 1991 until it was merged with Genzyme Corp. in December 2000, Mr. Carpenter was Chairman of GelTex Pharmaceuticals, Inc., a pharmaceutical development company which he co-founded in November 1991 and where he served as President and Chief Executive Officer until May 1993. He was President and Chief Executive Officer of VacTex, Inc., a privately held biotechnology company that he co-founded, from November 1995 until its acquisition by Aquila Biopharmaceuticals, Inc. in April 1998. Mr. Carpenter was Chairman of the Board, President and Chief Executive Officer of Integrated Genetics, Inc., a biotechnology company that merged with Genzyme Corp. in 1989. Following the merger and until 1991, Mr. Carpenter was Executive Vice President of Genzyme Corp. and Chief Executive Officer and Chairman of the Board of IG Laboratories, Inc. He is also a director of Cardiac Science, Inc.

Charles L. Cooney, Ph.D.
Director since 1983

        Dr. Cooney is a Professor of Chemical and Biochemical Engineering, Faculty Director, Deshpande Center for Technological Innovation and Co-Director of the Program on the Pharmaceutical Industry at Massachusetts Institute of Technology (Building #66, Room 352, Cambridge, Massachusetts 02139). Dr. Cooney joined the MIT faculty as an Assistant Professor in 1970 and became a Professor in 1982. Dr. Cooney is a director of CUNO, Inc., a high technology manufacturer of filtration products for separation, clarification and purification of liquids and gases. He is also a principal of BioInformation Associates, Inc., a consulting company.

Victor J. Dzau, M.D.
Director since 2000

        Dr. Dzau is the Hersey Professor of the Theory and Practice of Medicine at the Harvard Medical School and Chairman of the Department of Medicine, Physician in Chief and Director of Research at the Brigham and Women's Hospital (75 Francis Street, Boston, MA 02115). Prior to this, Dr. Dzau was the Arthur L. Bloomfield Professor and Chairman of the Department of Medicine at Stanford University. Dr. Dzau also serves as a director of Corgentech, Inc. and serves on the board of trustees of Partners Healthcare System and Brigham and Women's Hospital.

Senator Connie Mack III
Director since 2001

        Senator Mack served as a United States Senator from the state of Florida from January 1989 until January 2001. He is currently a senior policy advisor to Shaw Pittman, a Washington, D.C. law firm (2300 N. Street, NW, Washington, DC 20037) and is also an advisory board member to Household International, Inc., a consumer financial services company. Senator Mack is also a director of Mutual of America, Darden Restaurants, EXACT Sciences Corporation, Moody's Corp. and LNR Properties.

Executive Officers

Henri A. Termeer
Chairman of the Board, President and Chief Executive Officer

        See above.

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Earl M. Collier, Jr.
Executive Vice President

        Mr. Collier joined Genzyme Corporation in January 1997 as Senior Vice President, Health Systems, and served as Executive Vice President, Surgical Products and Health Systems from July 1997 until June 1999. He served as President of Genzyme Surgical Products from June 1999 until December 2000. Mr. Collier was also responsible for Genzyme Tissue Repair from December 1999 to December 2000. Mr. Collier served as President of Genzyme Biosurgery from December 2000 until June 2003. Prior to joining Genzyme, Mr. Collier was President of Vitas HealthCare Corporation (formerly Hospice Care Incorporated), a provider of health care services, from October 1991 until August 1995. Prior to that, Mr. Collier was a partner in the Washington, D.C. law firm of Hogan & Hartson, which he joined in 1981.

Zoltan A. Csimma
Senior Vice President, Human Resources

        Mr. Csimma joined Genzyme Corporation in July 2000 as Senior Vice President, Human Resources. Prior to joining Genzyme, he served as Vice President, Human Resources of Wyeth Ayerst Research, a pharmaceutical research organization (Radnor, Pennsylvania), from August 1998 to July 2000. During that time, Mr. Csimma also served as Site Head, Genetics Institute, for Wyeth Ayerst. From May 1988 to August 1998, he served as Vice President, Human Resources and Operations, of Genetics Institute, Inc., a biotechnology company (Cambridge, Massachusetts), which was integrated into Wyeth Ayerst in March 1998.

Richard A. Moscicki, M.D.
Chief Medical Officer; Senior Vice President, Clinical, Medical and Regulatory Affairs

        Dr. Moscicki joined Genzyme Corporation in March 1992 as Medical Director, became Vice President, Medical Affairs in early 1993 and was named Vice President, Clinical, Medical and Regulatory Affairs in December 1993. In September 1996 he became Senior Vice President, Clinical, Medical and Regulatory Affairs and Chief Medical Officer. Since 1979, he has also been a physician staff member at the Massachusetts General Hospital and a faculty member at the Harvard Medical School.

Alan E. Smith, Ph.D.
Chief Scientific Officer; Senior Vice President, Research

        Dr. Smith joined Genzyme Corporation in August 1989 as Senior Vice President, Research and became Chief Scientific Officer in September 1996. Prior to joining Genzyme Corporation, he served as Vice President-Scientific Director of Integrated Genetics, Inc. from November 1984 until its acquisition by Genzyme Corporation in August 1989. From October 1980 to October 1984, Dr. Smith was head of the Biochemistry Division of the National Institute for Medical Research, Mill Hill, London, England, and from 1972 to October 1980 he was a member of the scientific staff at the Imperial Cancer Research Fund in London, England.

G. Jan van Heek
Executive Vice President

        Mr. van Heek joined Genzyme Corporation in September 1991 as General Manager of its wholly-owned subsidiary, Genzyme, B.V., and became a corporate Vice President and President of its therapeutics business unit in December 1993. From September 1996 through July 1997, he served as Group Senior Vice President, Therapeutics and from July 1997 through December 1999 served as Executive Vice President, Therapeutics and Tissue Repair. Since January 2000, he has served as

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Executive Vice President, Therapeutics and Genetics, with responsibility for Genzyme Corporation's Therapeutics, Renal and Genetics business units and international operations. He also is responsible for Genzyme's pharmaceuticals business. Prior to joining Genzyme, Mr. van Heek was Vice President/General Manager of the Fenwal Division of Baxter Healthcare Corporation.

Peter Wirth
Chief Legal Officer; Executive Vice President, Legal, Corporate Development and Drug Discovery and Development; Clerk

        Mr. Wirth joined Genzyme Corporation in January 1996 and has served as Executive Vice President and Chief Legal Officer since September 1996. Mr. Wirth has responsibility for Genzyme Corporation's corporate development and legal activities, Genzyme Molecular Oncology and Genzyme Corporation's GelTex Pharmaceuticals subsidiary. From January 1996 to September 1996, Mr. Wirth served as Senior Vice President and General Counsel of Genzyme Corporation. Mr. Wirth was a partner of Palmer & Dodge LLP, a Boston, Massachusetts law firm, from 1982 through September 1996. Mr. Wirth remains of counsel to Palmer & Dodge LLP.

Michael S. Wyzga
Chief Financial and Accounting Officer; Executive Vice President, Finance

        Mr. Wyzga joined Genzyme Corporation in February 1998 as Vice President and Corporate Controller, served as Senior Vice President, Corporate Controller and Chief Accounting Officer since January 1999, and as Senior Vice President, Finance and Chief Financial Officer since July 1999. Prior to joining Genzyme Corporation, from February 1997 to February 1998, Mr. Wyzga served as Chief Financial Officer of Sovereign Hill Software, Inc. (100 Venture Way, Hadley, Massachusetts 01035), a software company, and from 1991 through 1997 held various senior management positions with CACHELINK Corporation and Lotus Development Corporation.

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Swift Starboard Corporation

Directors

Richard Douglas, Ph.D.
Director since 2003

        Dr. Douglas is the Senior Vice President, Corporate Development of Genzyme Corporation and has served in that role since 1996. From 1989 to 1996, Dr. Douglas was the Vice President, Corporate Development of Genzyme Corporation. From 1982 until its merger with Genzyme Corporation in 1989, Dr. Douglas served in science and corporate development capacities at Integrated Genetics, a biotechnology company. Dr. Douglas serves as a director of Iomai Corporation, a private biopharmaceutical company.

James A. Geraghty
Director since 2003

        Mr. Geraghty is Senior Vice President of International Development and an officer of Genzyme Corporation, where he was earlier President of Genzyme Europe. He also serves as a Director of GTC Biotherapeutics, where he was Chairman from 1998 to 2001, and President and Chief Executive Officer from its founding in February 1993 until 1998. Mr. Geraghty joined Genzyme Corporation in September 1992, where he held the posts of Vice President Corporate Development and General Manager of the transgenics business unit until it was spun off into GTC Biotherapeutics. He also serves as a member of the Advisory Board of the KBC Biotech Fund, based in Brussels.

Executive Officers

G. Jan van Heek
President

        See above, under "Genzyme Corporation."

James Geraghty
Vice President

        See above.

Michael S. Wyzga
Treasurer

        See above, under "Genzyme Corporation."

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ANNEX II

Section 262 of the Delaware General Corporation Law
Rights of Appraisal

        (a)   Any stockholder of a corporation of this State who holds shares of stock on the date of the making of a demand pursuant to subsection (d) of this section with respect to such shares, who continuously holds such shares through the effective date of the merger or consolidation, who has otherwise complied with subsection (d) of this section and who has neither voted in favor of the merger or consolidation nor consented thereto in writing pursuant to § 228 of this title shall be entitled to an appraisal by the Court of Chancery of the fair value of the stockholder's shares of stock under the circumstances described in subsections (b) and (c) of this section. As used in this section, the word "stockholder" means a holder of record of stock in a stock corporation and also a member of record of a nonstock corporation; the words "stock" and "share" mean and include what is ordinarily meant by those words and also membership or membership interest of a member of a nonstock corporation; and the words "depository receipt" mean a receipt or other instrument issued by a depository representing an interest in one or more shares, or fractions thereof, solely of stock of a corporation, which stock is deposited with the depository.

        (b)   Appraisal rights shall be available for the shares of any class or series of stock of a constituent corporation in a merger or consolidation to be effected pursuant to § 251 (other than a merger effected pursuant to § 251(g) of this title), § 252, § 254, § 257, § 258, § 263 or § 264 of this title:

        (1)   Provided, however, that no appraisal rights under this section shall be available for the shares of any class or series of stock, which stock, or depository receipts in respect thereof, at the record date fixed to determine the stockholders entitled to receive notice of and to vote at the meeting of stockholders to act upon the agreement of merger or consolidation, were either (i) listed on a national securities exchange or designated as a national market system security on an interdealer quotation system by the National Association of Securities Dealers, Inc. or (ii) held of record by more than 2,000 holders; and further provided that no appraisal rights shall be available for any shares of stock of the constituent corporation surviving a merger if the merger did not require for its approval the vote of the stockholders of the surviving corporation as provided in subsection (f) of § 251 of this title.

        (2)   Notwithstanding paragraph (1) of this subsection, appraisal rights under this section shall be available for the shares of any class or series of stock of a constituent corporation if the holders thereof are required by the terms of an agreement of merger or consolidation pursuant to §§ 251, 252, 254, 257, 258, 263 and 264 of this title to accept for such stock anything except:

        a.     Shares of stock of the corporation surviving or resulting from such merger or consolidation, or depository receipts in respect thereof;

        b.     Shares of stock of any other corporation, or depository receipts in respect thereof, which shares of stock (or depository receipts in respect thereof) or depository receipts at the effective date of the merger or consolidation will be either listed on a national securities exchange or designated as a national market system security on an interdealer quotation system by the National Association of Securities Dealers, Inc. or held of record by more than 2,000 holders;

        c.     Cash in lieu of fractional shares or fractional depository receipts described in the foregoing subparagraphs a. and b. of this paragraph; or

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        d.     Any combination of the shares of stock, depository receipts and cash in lieu of fractional shares or fractional depository receipts described in the foregoing subparagraphs a., b., and c. of this paragraph.

        (3)   In the event all of the stock of a subsidiary Delaware corporation party to a merger effected under § 253 of this title is not owned by the parent corporation immediately prior to the merger, appraisal rights shall be available for the shares of the subsidiary Delaware corporation.

        (c)   Any corporation may provide in its certificate of incorporation that appraisal rights under this section shall be available for the shares of any class or series of its stock as a result of an amendment to its certificate of incorporation, any merger or consolidation in which the corporation is a constituent corporation or the sale of all or substantially all of the assets of the corporation. If the certificate of incorporation contains such a provision, the procedures of this section, including those set forth in subsections (d) and (e) of this section, shall apply as nearly as is practicable.

        (d)   Appraisal rights shall be perfected as follows:

        (1)   If a proposed merger or consolidation for which appraisal rights are provided under this section is to be submitted for approval at a meeting of stockholders, the corporation, not less than 20 days prior to the meeting, shall notify each of its stockholders who was such on the record date for such meeting with respect to shares for which appraisal rights are available pursuant to subsection (b) or (c) hereof that appraisal rights are available for any or all of the shares of the constituent corporations, and shall include in such notice a copy of this section. Each stockholder electing to demand the appraisal of such stockholder's shares shall deliver to the corporation, before the taking of the vote on the merger or consolidation, a written demand for appraisal of such stockholder's shares. Such demand will be sufficient if it reasonably informs the corporation of the identity of the stockholder and that the stockholder intends thereby to demand the appraisal of such stockholder's shares. A proxy or vote against the merger or consolidation shall not constitute such a demand. A stockholder electing to take such action must do so by a separate written demand as herein provided. Within 10 days after the effective date of such merger or consolidation, the surviving or resulting corporation shall notify each stockholder of each constituent corporation who has complied with this subsection and has not voted in favor of or consented to the merger or consolidation of the date that the merger or consolidation has become effective; or

        (2)   If the merger or consolidation was approved pursuant to § 228 or § 253 of this title, then either a constituent corporation before the effective date of the merger or consolidation or the surviving or resulting corporation within 10 days thereafter shall notify each of the holders of any class or series of stock of such constituent corporation who are entitled to appraisal rights of the approval of the merger or consolidation and that appraisal rights are available for any or all shares of such class or series of stock of such constituent corporation, and shall include in such notice a copy of this section. Such notice may, and, if given on or after the effective date of the merger or consolidation, shall, also notify such stockholders of the effective date of the merger or consolidation. Any stockholder entitled to appraisal rights may, within 20 days after the date of mailing of such notice, demand in writing from the surviving or resulting corporation the appraisal of such holder's shares. Such demand will be sufficient if it reasonably informs the corporation of the identity of the stockholder and that the stockholder intends thereby to demand the appraisal of such holder's shares. If such notice did not notify stockholders of the effective date of the merger or consolidation, either (i) each such constituent corporation shall send a second notice before the effective date of the merger or consolidation notifying each of the holders of any class or series of stock of such constituent corporation that are entitled to appraisal rights of the effective date of the merger or consolidation or (ii) the surviving or resulting corporation shall send such a second notice to all such holders on or within 10 days after such effective date; provided, however, that if

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such second notice is sent more than 20 days following the sending of the first notice, such second notice need only be sent to each stockholder who is entitled to appraisal rights and who has demanded appraisal of such holder's shares in accordance with this subsection. An affidavit of the secretary or assistant secretary or of the transfer agent of the corporation that is required to give either notice that such notice has been given shall, in the absence of fraud, be prima facie evidence of the facts stated therein. For purposes of determining the stockholders entitled to receive either notice, each constituent corporation may fix, in advance, a record date that shall be not more than 10 days prior to the date the notice is given, provided, that if the notice is given on or after the effective date of the merger or consolidation, the record date shall be such effective date. If no record date is fixed and the notice is given prior to the effective date, the record date shall be the close of business on the day next preceding the day on which the notice is given.

        (e)   Within 120 days after the effective date of the merger or consolidation, the surviving or resulting corporation or any stockholder who has complied with subsections (a) and (d) hereof and who is otherwise entitled to appraisal rights, may file a petition in the Court of Chancery demanding a determination of the value of the stock of all such stockholders. Notwithstanding the foregoing, at any time within 60 days after the effective date of the merger or consolidation, any stockholder shall have the right to withdraw such stockholder's demand for appraisal and to accept the terms offered upon the merger or consolidation. Within 120 days after the effective date of the merger or consolidation, any stockholder who has complied with the requirements of subsections (a) and (d) hereof, upon written request, shall be entitled to receive from the corporation surviving the merger or resulting from the consolidation a statement setting forth the aggregate number of shares not voted in favor of the merger or consolidation and with respect to which demands for appraisal have been received and the aggregate number of holders of such shares. Such written statement shall be mailed to the stockholder within 10 days after such stockholder's written request for such a statement is received by the surviving or resulting corporation or within 10 days after expiration of the period for delivery of demands for appraisal under subsection (d) hereof, whichever is later.

        (f)    Upon the filing of any such petition by a stockholder, service of a copy thereof shall be made upon the surviving or resulting corporation, which shall within 20 days after such service file in the office of the Register in Chancery in which the petition was filed a duly verified list containing the names and addresses of all stockholders who have demanded payment for their shares and with whom agreements as to the value of their shares have not been reached by the surviving or resulting corporation. If the petition shall be filed by the surviving or resulting corporation, the petition shall be accompanied by such a duly verified list. The Register in Chancery, if so ordered by the Court, shall give notice of the time and place fixed for the hearing of such petition by registered or certified mail to the surviving or resulting corporation and to the stockholders shown on the list at the addresses therein stated. Such notice shall also be given by 1 or more publications at least 1 week before the day of the hearing, in a newspaper of general circulation published in the City of Wilmington, Delaware or such publication as the Court deems advisable. The forms of the notices by mail and by publication shall be approved by the Court, and the costs thereof shall be borne by the surviving or resulting corporation.

        (g)   At the hearing on such petition, the Court shall determine the stockholders who have complied with this section and who have become entitled to appraisal rights. The Court may require the stockholders who have demanded an appraisal for their shares and who hold stock represented by certificates to submit their certificates of stock to the Register in Chancery for notation thereon of the pendency of the appraisal proceedings; and if any stockholder fails to comply with such direction, the Court may dismiss the proceedings as to such stockholder.

        (h)   After determining the stockholders entitled to an appraisal, the Court shall appraise the shares, determining their fair value exclusive of any element of value arising from the accomplishment or expectation of the merger or consolidation, together with a fair rate of interest, if any, to be paid upon the amount determined to be the fair value. In determining such fair value, the Court shall take

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into account all relevant factors. In determining the fair rate of interest, the Court may consider all relevant factors, including the rate of interest which the surviving or resulting corporation would have had to pay to borrow money during the pendency of the proceeding. Upon application by the surviving or resulting corporation or by any stockholder entitled to participate in the appraisal proceeding, the Court may, in its discretion, permit discovery or other pretrial proceedings and may proceed to trial upon the appraisal prior to the final determination of the stockholder entitled to an appraisal. Any stockholder whose name appears on the list filed by the surviving or resulting corporation pursuant to subsection (f) of this section and who has submitted such stockholder's certificates of stock to the Register in Chancery, if such is required, may participate fully in all proceedings until it is finally determined that such stockholder is not entitled to appraisal rights under this section.

        (i)    The Court shall direct the payment of the fair value of the shares, together with interest, if any, by the surviving or resulting corporation to the stockholders entitled thereto. Interest may be simple or compound, as the Court may direct. Payment shall be so made to each such stockholder, in the case of holders of uncertificated stock forthwith, and the case of holders of shares represented by certificates upon the surrender to the corporation of the certificates representing such stock. The Court's decree may be enforced as other decrees in the Court of Chancery may be enforced, whether such surviving or resulting corporation be a corporation of this State or of any state.

        (j)    The costs of the proceeding may be determined by the Court and taxed upon the parties as the Court deems equitable in the circumstances. Upon application of a stockholder, the Court may order all or a portion of the expenses incurred by any stockholder in connection with the appraisal proceeding, including, without limitation, reasonable attorney's fees and the fees and expenses of experts, to be charged pro rata against the value of all the shares entitled to an appraisal.

        (k)   From and after the effective date of the merger or consolidation, no stockholder who has demanded appraisal rights as provided in subsection (d) of this section shall be entitled to vote such stock for any purpose or to receive payment of dividends or other distributions on the stock (except dividends or other distributions payable to stockholders of record at a date which is prior to the effective date of the merger or consolidation); provided, however, that if no petition for an appraisal shall be filed within the time provided in subsection (e) of this section, or if such stockholder shall deliver to the surviving or resulting corporation a written withdrawal of such stockholder's demand for an appraisal and an acceptance of the merger or consolidation, either within 60 days after the effective date of the merger or consolidation as provided in subsection (e) of this section or thereafter with the written approval of the corporation, then the right of such stockholder to an appraisal shall cease. Notwithstanding the foregoing, no appraisal proceeding in the Court of Chancery shall be dismissed as to any stockholder without the approval of the Court, and such approval may be conditioned upon such terms as the Court deems just.

        (l)    The shares of the surviving or resulting corporation to which the shares of such objecting stockholders would have been converted had they assented to the merger or consolidation shall have the status of authorized and unissued shares of the surviving or resulting corporation.

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        Manually signed facsimile copies of the Letter of Transmittal will be accepted. The Letter of Transmittal, certificates for Shares and any other required documents should be sent or delivered by each stockholder of SangStat or such stockholder's broker, dealer, commercial bank, trust company or other nominee to the Depositary at one of its addresses set forth below.

The Depositary for the Offer is:

American Stock Transfer & Trust Company

By Mail:	By Overnight Delivery:	By Hand:
59 Maiden Lane Plaza Level New York, NY 10038	Operations Center 6201 15th Avenue Brooklyn, NY 11219	(9:00 a.m. - 5:00 p.m. New York City Time) 59 Maiden Lane Plaza Level New York, NY 10038
	By Facsimile Transmission:
	(718) 236-2641 Confirm by Telephone: (800) 937-5449

        Questions and requests for assistance may be directed to the Information Agent or the Dealer Manager and requests for additional copies of this Offer to Purchase, the Letter of Transmittal and the Notice of Guaranteed Delivery may be directed to the Information Agent at their respective telephone numbers and locations listed below. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance concerning the Offer.

The Information Agent for the Offer is:

501 Madison Avenue, 20th Floor
New York, NY 10022
Banks and Brokers Call Collect: (212) 750-5833
All Others Call Toll-Free: (888) 750-5834

The Dealer Manager for the Offer is:

Credit Suisse First Boston LLC
Eleven Madison Avenue
New York, NY 10010-3629
Call Toll Free (800) 881-8320

EX-99.(A)(2)

Exhibit 99(a)(2)

Letter of Transmittal
To Tender
Shares of Common Stock
(Including the Associated Preferred Stock Purchase Rights)
of
SangStat Medical Corporation
at
$22.50 Net Per Share
Pursuant to the Offer to Purchase
dated August 13, 2003
by
Swift Starboard Corporation
a wholly-owned subsidiary of

Genzyme Corporation

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, SEPTEMBER 10, 2003, UNLESS THE OFFER IS EXTENDED.

TO: AMERICAN STOCK TRANSFER & TRUST COMPANY, DEPOSITARY

By Mail:	By Overnight Delivery:	By Hand:
59 Maiden Lane Plaza Level New York, NY 10038	Operations Center 6201 15th Avenue Brooklyn, NY 11219	(9:00 a.m. - 5:00 p.m. New York City Time) 59 Maiden Lane Plaza Level New York, NY 10038
	For Notice of Guaranteed Delivery (for Eligible Institutions only) By Facsimile Transmission: (718) 236-2641
	Confirm by Telephone: (800) 937-5449

        DELIVERY OF THIS LETTER OF TRANSMITTAL TO AN ADDRESS, OR TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE NUMBER, OTHER THAN AS SET FORTH ABOVE, DOES NOT CONSTITUTE A VALID DELIVERY.

        THE INSTRUCTIONS SET FORTH IN THIS LETTER OF TRANSMITTAL SHOULD BE READ CAREFULLY BEFORE THIS LETTER OF TRANSMITTAL IS COMPLETED.

        This Letter of Transmittal is to be used by stockholders of SangStat Medical Corporation either if certificates for Shares (as defined below) are to be forwarded herewith or, unless an Agent's Message (as defined in Section 2 of the Offer to Purchase (as defined below)) is utilized, if delivery of Shares is to be made by book-entry transfer to an account maintained by the Depositary at the Book-Entry Transfer Facility (as defined in, and pursuant to the procedures set forth in, Section 2 of the Offer to Purchase). Stockholders who deliver Shares by book-entry transfer are referred to herein as "Book-Entry Shareholders" and other stockholders are referred to herein as "Certificate Shareholders." Stockholders whose certificates for Shares are not immediately available or who cannot deliver either the certificates for, or a Book-Entry Confirmation (as defined in the Offer to Purchase) with respect to their Shares, and all other documents required hereby to the Depositary prior to the Expiration Date (as defined in the Offer to Purchase) must tender their Shares in accordance with the guaranteed delivery procedures set forth in Section 2 of the Offer to Purchase. See Instruction 2.

Delivery of documents to the Book-Entry Transfer Facility does not constitute delivery to the Depositary.

DESCRIPTION OF SHARES TENDERED
		Shares Tendered (Attach additional signed list if necessary)
Name(s) and Address(es) of Registered Holder(s) (Please fill in, if blank, exactly as name(s) appear(s) on Share Certificate(s))		Share Certificate Number(s)*	Total Number of Shares Represented by Share Certificate(s)*	Number of Shares Tendered**
		Total Shares
*	Need not be completed if transfer is made by book-entry transfer.
**	Unless otherwise indicated, it will be assumed that all Shares described above are being tendered. See Instruction 4.

SEE INSTRUCTION 11 IF ANY OF THE CERTIFICATES REPRESENTING SHARES THAT YOU OWN HAVE BEEN LOST OR DESTROYED.

o

CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER MADE TO AN ACCOUNT MAINTAINED BY THE DEPOSITARY WITH THE BOOK-ENTRY TRANSFER FACILITY AND COMPLETE THE FOLLOWING (ONLY PARTICIPANTS IN THE BOOK-ENTRY TRANSFER FACILITY MAY DELIVER SHARES BY BOOK-ENTRY TRANSFER):

        Name of Tendering Institution

        Account Number

        Transaction Code Number

o

CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED PURSUANT TO A NOTICE OF GUARANTEED DELIVERY PREVIOUSLY SENT TO THE DEPOSITARY, ENCLOSE A PHOTOCOPY OF SUCH NOTICE OF GUARANTEED DELIVERY AND COMPLETE THE FOLLOWING:

        Name(s) of Registered Owner(s)

        Date of Execution of Notice of Guaranteed Delivery

        Name of Institution that Guaranteed Delivery

        If delivered by book-entry transfer check box: o

                Account Number

                Transaction Code Number

o

CHECK HERE IF ANY OF THE CERTIFICATES REPRESENTING SHARES THAT YOU OWN HAVE BEEN LOST OR DESTROYED AND SEE INSTRUCTION 11.

        Number of Shares represented by the lost or destroyed certificates

NOTE: SIGNATURES MUST BE PROVIDED BELOW
PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY

Ladies and Gentlemen:

        The undersigned hereby tenders to Swift Starboard Corporation, a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation ("Parent"), the above-described shares of common stock, par value $0.001 per share, including all preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, by and between SangStat Medical Corporation and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares"), of SangStat Medical Corporation, a Delaware corporation (the "Company"), upon the terms and subject to the conditions set forth in the Purchaser's Offer to Purchase dated August 13, 2003 (the "Offer to Purchase") and this Letter of Transmittal (which, together with any amendments or supplements thereto or hereto, collectively constitute the "Offer"), receipt of which is hereby acknowledged.

        Upon the terms of the Offer, subject to, and effective upon acceptance for payment of, and payment for, the Shares tendered herewith in accordance with the terms of the Offer, the undersigned hereby sells, assigns and transfers to, or upon the order of, the Purchaser, all right, title and interest in and to all of the Shares that are being tendered hereby (and any and all other Shares or other securities or rights issued in respect thereof on or after the date of the Offer to Purchase) and irrevocably constitutes and appoints American Stock Transfer & Trust Company (the "Depositary"), the true and lawful agent and attorney-in-fact of the undersigned, with full power of substitution (such power of attorney being deemed to be an irrevocable power coupled with an interest), to the full extent of the undersigned's rights with respect to such Shares (and any such other Shares or securities or rights) (a) to deliver certificates for such Shares (and any such other Shares or securities or rights) or transfer ownership of such Shares (and any such other Shares or securities or rights) on the account books maintained by the Book-Entry Transfer Facility together, in any such case, with all accompanying evidences of transfer and authenticity to, or upon the order of, the Purchaser, (b) to present such Shares (and any such other Shares or securities or rights) for transfer on the Company's books and (c) to receive all benefits and otherwise exercise all rights of beneficial ownership of such Shares (and any such other Shares or securities or rights), all in accordance with the terms and subject to the conditions of the Offer.

        The undersigned hereby represents and warrants that the undersigned has full power and authority to tender, sell, assign and transfer the tendered Shares (and any and all other Shares or other securities or rights issued or issuable in respect of such Shares on or after the date of the Offer to Purchase) and, when the same are accepted for payment by the Purchaser, the Purchaser will acquire good title thereto, free and clear of all liens, restrictions, claims and encumbrances and the same will not be subject to any adverse claim. The undersigned will, upon request, execute and deliver any additional documents deemed by the Depositary or the Purchaser to be necessary or desirable to complete the sale, assignment and transfer of the tendered Shares (and any such other Shares or other securities or rights).

        All authority conferred or agreed to be conferred pursuant to this Letter of Transmittal shall be binding upon the successors, assigns, heirs, executors, administrators and legal representatives of the undersigned and shall not be affected by, and shall survive, the death or incapacity of the undersigned. Except as stated in the Offer to Purchase, this tender is irrevocable.

        The undersigned hereby irrevocably appoints the designees of the Purchaser, and each of them, and any other designees of the Purchaser, the attorneys-in-fact and proxies of the undersigned, each with full power of substitution, to vote at any annual, special or adjourned meeting of the Company's stockholders or otherwise in such manner, to execute any written consent concerning any matter, and to otherwise act as each such attorney-in-fact and proxy or his or her substitute shall in his or her sole discretion deem proper with respect to the Shares tendered hereby that have been accepted for payment by the Purchaser prior to the time any such action is taken and with respect to which the

undersigned is entitled to vote (and any and all other Shares or other securities or rights issued or issuable in respect of such Shares on or after the date of the Offer to Purchase). This appointment is effective when, and only to the extent that, the Purchaser accepts for payment such Shares as provided in the Offer to Purchase. This power of attorney and proxy are irrevocable and are granted in consideration of the acceptance for payment of such Shares in accordance with the terms of the Offer. Upon such acceptance for payment, all prior powers of attorney, proxies and consents given by the undersigned with respect to such Shares (and any such other Shares or securities or rights) will, without further action, be revoked and no subsequent powers of attorney, proxies, consents or revocations may be given (and, if given, will not be deemed effective) by the undersigned with respect to such Shares.

        The undersigned understands that the valid tender of Shares pursuant to any of the procedures described in Section 2 of the Offer to Purchase and in the Instructions hereto will constitute a binding agreement between the undersigned and the Purchaser upon the terms and subject to the conditions of the Offer (and if the Offer is extended or amended, the terms and conditions of any such extension or amendment). Without limiting the foregoing, if the price to be paid in the Offer is amended in accordance with the Merger Agreement (as defined in the Offer to Purchase), the price to be paid to the undersigned will be the amended price notwithstanding the fact that a different price is stated in this Letter of Transmittal. The undersigned recognizes that under certain circumstances set forth in the Offer to Purchase, the Purchaser may not be required to accept for payment any of the Shares tendered hereby.

        Unless otherwise indicated herein under "Special Payment Instructions," please issue the check for the purchase price and/or return any certificates for Shares not tendered or accepted for payment in the name(s) of the registered holder(s) appearing under "Description of Shares Tendered." Similarly, unless otherwise indicated under "Special Delivery Instructions," please mail the check for the purchase price and/or return any certificates for Shares not tendered or accepted for payment (and any accompanying documents, as appropriate) to the address(es) of the registered holder(s) appearing under "Description of Shares Tendered." In the event that both the "Special Delivery Instructions" and the "Special Payment Instructions" are completed, please issue the check for the purchase price and/or return any certificates for Shares not tendered or accepted for payment (and any accompanying documents, as appropriate) in the name(s) of, and deliver such check and/or return such certificates (and any accompanying documents, as appropriate) to, the person(s) so indicated. Please credit any Shares tendered herewith by book-entry transfer that are not accepted for payment by crediting the account at the Book-Entry Transfer Facility designated above. The undersigned recognizes that the Purchaser has no obligation pursuant to the "Special Payment Instructions" to transfer any Shares from the name of the registered holder thereof if the Purchaser does not accept for payment any of the Shares so tendered.

SPECIAL PAYMENT INSTRUCTIONS
(See Instructions 1, 5, 6 and 7)

        To be completed ONLY if the check for the purchase price of Shares tendered and accepted for payment and/or certificates for Shares not tendered or not accepted for payment is/are to be issued in the name of someone other than the undersigned.

Issue: o Check
o Certificate(s) to:

Name:

(Please Print)

Address:

(Include Zip Code)

(Tax Identification or Social Security Number)

SPECIAL DELIVERY INSTRUCTIONS
(See Instructions 1, 5, 6 and 7)

        To be completed ONLY if the check for the purchase price of Shares tendered and accepted for payment and/or certificates for Shares not tendered or not accepted for payment is/are to be sent to someone other than the undersigned or to the undersigned at an address other than that above.

Issue: o Check
o Certificate(s) to:

Name:

(Please Print)

Address:

(Include Zip Code)

(Tax Identification or Social Security Number)

SIGN HERE
(Also complete Substitute Form W-9 on the other side of this form)

(Signature(s) of Stockholder(s))

Dated:                                                  , 2003

(Must be signed by the registered holder(s) exactly as the name(s) appear(s) on the certificate(s) for the Shares or on a security position listing or by person(s) authorized to become registered holder(s) by certificates and documents transmitted herewith. If signature is by trustee, executor, administrator, guardian, attorney-in-fact, officer of corporation or others acting in a fiduciary or representative capacity, please provide the following information and see Instruction 5.)

Name(s):

(Please Print)

Capacity (Full Title):

Address:

(Include Zip Code)

Daytime Area Code and Telephone Number:

Employer Identification or
Social Security Number:

(See Substitute Form W-9)

GUARANTEE OF SIGNATURE(S)
(If Required—See Instructions 1 and 5)

Authorized Signature:

Name:

(Please Print)

Title:

Name of Firm:

Address:

(Include Zip Code)

Daytime Area Code and Telephone Number:

Dated:                                                  , 2003

SUBSTITUTE FORM W-9 Department of the Treasury Internal Revenue Service	Name: Business Name (if different): Address:
Payer's Request for Taxpayer Identification Number (TIN)	Part 1—PLEASE PROVIDE YOUR TIN IN THE BOX AT RIGHT AND CERTIFY BY SIGNING AND DATING BELOW.	Social Security Number(s) OR      Employer Identification Number

Part 2—Certificates—Under penalties of perjury, I certify that

(1)

the number shown on this form is my correct Taxpayer Identification Number (or I am waiting for a number to be issued to me);

(2)

I am not subject to backup withholding because: (a) I am exempt from backup withholding, or (b) I have not been notified by the Internal Revenue Service (the "IRS") that I am subject to backup withholding as a result of a failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup withholding; and

(3)

I am a U.S. Person (including a U.S. resident alien).

Part 3 o    Awaiting TIN

Part 4—Check appropriate box(es):

o Individual / Sole Proprietor	o Exempt from backup withholding
o Partnership
o Corporation
o Other (specify):

Certification Instructions—You must cross out item (2) in Part 2 above if you have been notified by the IRS that you are subject to backup withholding because of underreporting interest or dividends on your tax returns. However, if after being notified by the IRS that you are subject to backup withholding, you received another notification from the IRS stating that you are no longer subject to backup withholding, do not cross out such item (2). If you are exempt from backup withholding, check the appropriate box in Part 4 above.

Signature:

Date:

NOTE: FAILURE TO COMPLETE AND RETURN THIS SUBSTITUTE FORM W-9 MAY RESULT IN BACKUP WITHHOLDING OF 28% OF ANY PAYMENTS MADE TO YOU PURSUANT TO THE OFFER. PLEASE REVIEW THE ENCLOSED GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL INFORMATION.

YOU MUST COMPLETE THE FOLLOWING CERTIFICATE IF YOU CHECKED
THE BOX IN PART 3 OF SUBSTITUTE FORM W-9.

CERTIFICATE OF AWAITING TAXPAYER IDENTIFICATION NUMBER

        I certify under penalties of perjury that a taxpayer identification number has not been issued to me, and either (a) I have mailed or delivered an application to receive a Taxpayer Identification Number to the appropriate Internal Revenue Service Center or Social Security Administration Office or (b) I intend to mail or deliver an application in the near future. I understand that if I do not provide a Taxpayer Identification Number to the Depositary, 28% percent of all reportable payments made to me will be withheld, but will be refunded to me if I provide a certified Taxpayer Identification Number within 60 days.

Signature: Date:

INSTRUCTIONS
FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER

        1.    Guarantee of Signatures.    No signature guarantee is required on this Letter of Transmittal if (a) this Letter of Transmittal is signed by the registered holder(s) (which term, for purposes of this Instruction, includes any participant in the Book-Entry Transfer Facility's system whose name appears on a security position listing as the owner of the Shares) of Shares tendered herewith and such registered holder has not completed either the box entitled "Special Delivery Instructions" or the box entitled "Special Payment Instructions" on this Letter of Transmittal or (b) the Shares tendered herewith are tendered for the account of a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program (such participant, an "Eligible Institution"). In all other cases, all signatures on this Letter of Transmittal must be guaranteed by an Eligible Institution. See Instruction 5.

        2.    Requirements of Tender.    This Letter of Transmittal is to be completed by stockholders either if certificates are to be forwarded herewith or, unless an Agent's Message (as defined below) is utilized, if delivery of Shares is to be made pursuant to the procedures for book-entry transfer set forth in Section 2 of the Offer to Purchase. For a stockholder validly to tender Shares pursuant to the Offer, either (a) a Letter of Transmittal (or a facsimile thereof), properly completed and duly executed, together with any required signature guarantees or, in the case of a book-entry transfer, an Agent's Message, and any other required documents, must be received by the Depositary at one of its addresses set forth herein prior to the Expiration Date (as defined in the Offer to Purchase) and either certificates for the tendered Shares must be received by the Depositary at one of such addresses or the Shares must be delivered pursuant to the procedures for book-entry transfer set forth herein (and a Book-Entry Confirmation (as defined in the Offer to Purchase) must be received by the Depositary), in each case, prior to the Expiration Date, or (b) the tendering stockholder must comply with the guaranteed delivery procedures set forth below and in Section 2 of the Offer to Purchase.

        Stockholders whose certificates for Shares are not immediately available or who cannot deliver their certificates and all other required documents to the Depositary or complete the procedures for book-entry transfer prior to the Expiration Date may tender their Shares by properly completing and duly executing the Notice of Guaranteed Delivery pursuant to the guaranteed delivery procedures set forth in Section 2 of the Offer to Purchase. Pursuant to such procedures, (a) such tender must be made by or through an Eligible Institution, (b) a properly completed and duly executed Notice of Guaranteed Delivery, substantially in the form provided by the Purchaser, must be received by the Depositary prior to the Expiration Date and (c) either (i) the certificates for tendered Shares together with this Letter of Transmittal (or facsimile thereof), properly completed and duly executed, and any required signature guarantees, and any other required documents must be received by the Depositary within three trading days after the date of execution of such Notice of Guaranteed Delivery or (ii) in the case of a book-entry transfer effected pursuant to the book-entry transfer procedures described in the Offer to Purchase, either this Letter of Transmittal (or facsimile thereof), properly completed and duly executed, and any required signature guarantees, or an Agent's Message, and any other required documents, must be received by the Depositary, such Shares must be delivered pursuant to the book-entry transfer procedures and a Book-Entry Confirmation must be received by the Depositary, in each case within three trading days after the date of execution of such Notice of Guaranteed Delivery. A "trading day" is any day on which the Nasdaq Stock Market is open for business.

        "Agent's Message" means a message transmitted by the Book-Entry Transfer Facility to, and received by, the Depositary and forming a part of a Book-Entry Confirmation that states that the Book-Entry Transfer Facility has received an express acknowledgment from the participant in the Book-Entry Transfer Facility tendering the Shares that such participant has received and agrees to be bound by the terms of this Letter of Transmittal and that the Purchaser may enforce such agreement against the participant.

The method of delivery of Shares, this Letter of Transmittal and all other required documents, including delivery through the Book-Entry Transfer Facility, is at the election and risk of the tendering stockholder. Shares will be deemed delivered only when actually received by the Depositary (including, in the case of a book-entry transfer, by Book-Entry Confirmation). If delivery is by mail, registered mail, with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

        No alternative, conditional or contingent tenders will be accepted and no fractional Shares will be purchased. All tendering stockholders, by execution of this Letter of Transmittal (or facsimile thereof), waive any right to receive any notice of the acceptance of their Shares for payment.

        3.    Inadequate Space.    If the space provided herein is inadequate, the certificate numbers and/or the number of Shares should be listed on a separate schedule attached hereto.

        4.    Partial Tenders (Applicable to Certificate Stockholders Only).    If fewer than all the Shares evidenced by any certificate submitted are to be tendered, fill in the number of Shares that are to be tendered in the box entitled "Number of Shares Tendered". In any such case, new certificate(s) for the remainder of the Shares that were evidenced by the old certificate(s) will be sent to the registered holder, unless otherwise provided in the appropriate box on this Letter of Transmittal, as soon as practicable after the acceptance for payment of, and payment for, the Shares tendered herewith. All Shares represented by certificates delivered to the Depositary will be deemed to have been tendered unless otherwise indicated.

        5.    Signatures on Letter of Transmittal, Stock Powers and Endorsements.    If this Letter of Transmittal is signed by the registered holder of the Shares tendered hereby, the signature must correspond with the name as written on the face of the certificate(s) without any change whatsoever.

        If any of the Shares tendered hereby are owned of record by two or more joint owners, all such owners must sign this Letter of Transmittal.

        If any tendered Shares are registered in different names on several certificates, it will be necessary to complete, sign and submit as many separate Letters of Transmittal as there are different registrations of certificates.

        If this Letter of Transmittal or any certificates or stock powers are signed by trustees, executors, administrators, guardians, attorneys-in-fact, officers of corporations or others acting in a fiduciary or representative capacity, such persons should so indicate when signing, and proper evidence satisfactory to the Purchaser of their authority so to act must be submitted.

        When this Letter of Transmittal is signed by the registered owner(s) of the Shares listed and transmitted hereby, no endorsements of certificates or separate stock powers are required unless payment is to be made to or certificates for Shares not tendered or accepted for payment are to be issued to a person other than the registered owner(s). Signatures on such certificates or stock powers must be guaranteed by an Eligible Institution.

        If the certificates for Shares are registered in the name of a person other than the signer of this Letter of Transmittal, or if payment is to be made or certificates for Shares not tendered or not accepted for payment are to be returned to a person other than the registered holder of the certificates surrendered, the tendered certificates must be endorsed or accompanied by appropriate stock powers, in either case signed exactly as the name or names of the registered holders or owners appear on the certificates, with the signatures on the certificates or stock powers guaranteed as aforesaid. See Instruction 1.

        6.    Stock Transfer Taxes.    The Purchaser will pay any stock transfer taxes with respect to the transfer and sale of Shares to it or its order pursuant to the Offer. If, however, payment of the purchase price is to be made to, or if certificates for Shares not tendered or accepted for payment are to be registered in the name of, any person(s) other than the registered owner(s), or if tendered certificates are registered in the name of any person(s) other than the person(s) signing this Letter of Transmittal, the amount of any stock transfer taxes (whether imposed on the registered owner(s) or the

other person(s)) payable on account of the transfer will be deducted from the purchase price unless satisfactory evidence of the payment of such taxes or exemption therefrom is submitted.

Except as provided in this Instruction 6, it will not be necessary for transfer tax stamps to be affixed to the certificates listed in this Letter of Transmittal.

        7.    Special Payment and Delivery Instructions.    If a check is to be issued in the name of, and/or certificates for Shares not accepted for payment are to be returned to, a person other than the signer of this Letter of Transmittal or if a check is to be sent and/or such certificates are to be returned to a person other than the signer of this Letter of Transmittal or to an address other than that shown above, the appropriate boxes on this Letter of Transmittal should be completed.

        8.    Waiver of Conditions.    The Purchaser reserves the absolute right in its sole discretion to waive any of the specified conditions (other than the Minimum Condition (as defined in the Offer to Purchase), which may be waived only with the consent of the board of directors of the Company) of the Offer, in whole or in part, in the case of any Shares tendered.

        9.    Backup Withholding.    In order to avoid backup withholding of U.S. federal income tax on payments of cash pursuant to the Offer, a stockholder tendering Shares in the Offer must, unless an exemption applies, provide the Depositary with such stockholder's correct taxpayer identification number ("TIN"), certify under penalties of perjury that such TIN is correct, and provide certain other certifications by completing the Substitute Form W-9 included in this Letter of Transmittal. If a stockholder does not provide such stockholder's correct TIN or fails to provide the required certifications, the Internal Revenue Service (the "IRS") may impose a penalty on such stockholder and payment of cash to such stockholder pursuant to the Offer may be subject to backup withholding of 28%. All stockholders tendering Shares pursuant to the Offer should complete and sign the main signature form and the Substitute Form W-9 to provide the information and certification necessary to avoid backup withholding (unless an applicable exemption exists and is proved in a manner satisfactory to the Purchaser and the Depositary).

        Backup withholding is not an additional tax. Rather, the amount of the backup withholding can be credited against the Federal income tax liability of the person subject to the backup withholding, provided that the required information is given to the IRS. If backup withholding results in an overpayment of tax, a refund can be obtained by the stockholder upon filing an income tax return.

        The stockholder is required to give the Depositary the TIN (i.e., social security number or employer identification number) of the record owner of the Shares. If the Shares are held in more than one name or are not in the name of the actual owner, consult the enclosed "Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9" for additional guidance on which number to report.

        The box in Part 3 of the Substitute Form W-9 may be checked if the tendering stockholder has not been issued a TIN and has applied for a TIN or intends to apply for a TIN in the near future. If the box in Part 3 is checked, the stockholder or other payee must also complete the Certificate of Awaiting Taxpayer Identification Number in order to avoid backup withholding. Notwithstanding that the box in Part 3 is checked and the Certificate of Awaiting Taxpayer Identification Number is completed, the Depositary will withhold 28% on all payments made prior to the time a properly certified TIN is provided to the Depositary. However, such amounts will be refunded to such stockholder if a TIN is provided to the Depositary within 60 days following the date of the Substitute Form W-9.

        Certain stockholders (including, among others, all corporations, individual retirement accounts and certain foreign individuals and entities) are not subject to backup withholding. Noncorporate foreign stockholders should complete and sign the main signature form and the appropriate Form W-8, Certificate of Foreign Status, a copy of which may be obtained from the Depositary, in order to avoid backup withholding. See the enclosed "Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9" for more instructions.

        10.    Requests for Assistance or Additional Copies.    Questions and requests for assistance may be directed to Innisfree M&A Incorporated (the "Information Agent") at its address listed below. Additional copies of the Offer to Purchase, this Letter of Transmittal, the Notice of Guaranteed Delivery and the Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9 may be obtained from the Information Agent or from brokers, dealers, banks, trust companies or other nominees.

        11.    Lost, Destroyed or Stolen Certificates.    If any certificate representing Shares has been lost, destroyed or stolen, the stockholder should promptly notify the Depositary by checking the appropriate box on this Letter of Transmittal and indicating the number of Shares so lost, destroyed or stolen, or call the Transfer Agent for the Shares, Equiserve Trust Company, N.A., at (877) 282-1168. The stockholder will then be instructed by the Transfer Agent as to the steps that must be taken in order to replace the certificate. This Letter of Transmittal and related documents cannot be processed until the procedures for replacing lost or destroyed certificates have been followed.

        IMPORTANT: THIS LETTER OF TRANSMITTAL (OR A MANUALLY SIGNED FACSIMILE THEREOF) TOGETHER WITH ANY SIGNATURE GUARANTEES, OR, IN THE CASE OF A BOOK-ENTRY TRANSFER, AN AGENT'S MESSAGE, AND ANY OTHER REQUIRED DOCUMENTS, MUST BE RECEIVED BY THE DEPOSITARY PRIOR TO THE EXPIRATION DATE AND EITHER CERTIFICATES FOR TENDERED SHARES MUST BE RECEIVED BY THE DEPOSITARY OR SHARES MUST BE DELIVERED PURSUANT TO THE PROCEDURES FOR BOOK-ENTRY TRANSFER, IN EACH CASE PRIOR TO THE EXPIRATION DATE, OR THE TENDERING STOCKHOLDER MUST COMPLY WITH THE PROCEDURES FOR GUARANTEED DELIVERY.

        Manually signed facsimile copies of this Letter of Transmittal will be accepted. This Letter of Transmittal, certificates for Shares and any other required documents should be sent or delivered by each stockholder of the Company or such stockholder's broker, dealer, commercial bank, trust company or other nominee to the Depositary at one of its addresses set forth below.

The Depositary for the Offer is:

AMERICAN STOCK TRANSFER & TRUST COMPANY

By Mail:	By Overnight Delivery:	By Hand:
59 Maiden Lane Plaza Level New York, NY 10038	Operations Center 6201 15th Avenue Brooklyn, NY 11219	(9:00 a.m. - 5:00 p.m. New York City Time) 59 Maiden Lane Plaza Level New York, NY 10038
	For Notice of Guaranteed Delivery (for Eligible Institutions only) By Facsimile Transmission: (718) 236-2641
	Confirm by Telephone: (800) 937-5449

        Questions and requests for assistance may be directed to the Information Agent or the Dealer Manager at their addresses and telephone numbers set forth below. Additional copies of the Offer to Purchase, this Letter of Transmittal and the Notice of Guaranteed Delivery may be obtained from the Information Agent. You may also contact your broker, dealer, bank, trust company or other nominee for assistance concerning the Offer.

The Information Agent for the Offer is:

501 Madison Avenue, 20th Floor
New York, NY 10022
Banks and Brokers Call Collect: (212) 750-5833
All Others Call Toll Free: (888) 750-5834

The Dealer Manager for the Offer is:

Credit Suisse First Boston LLC
Eleven Madison Avenue
New York, NY 10010-3629
Call Toll Free: (800) 881-8320

EX-99.(A)(3)

Exhibit 99(a)(3)

Notice of Guaranteed Delivery
for
Tender of Shares of Common Stock
(Including the Associated Preferred Stock Purchase Rights)
of
SangStat Medical Corporation
at
$22.50 Net Per Share
Pursuant to the Offer to Purchase
dated August 13, 2003
by
Swift Starboard Corporation
a wholly-owned subsidiary of
Genzyme Corporation

        As set forth in Section 2 of the Offer to Purchase (as defined below), this form or one substantially equivalent hereto must be used to accept the Offer (as defined below) if certificates representing shares of common stock, par value $0.001 per share, of SangStat Medical Corporation, a Delaware corporation ("SangStat"), including the associated preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, by and between SangStat and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares"), are not immediately available or if the procedures for book-entry transfer cannot be completed on a timely basis or time will not permit all required documents to reach the Depositary prior to the Expiration Date (as defined in the Offer to Purchase). This form may be delivered by hand or transmitted by facsimile transmission or mail to the Depositary and must include a guarantee by an Eligible Institution (as defined in the Offer to Purchase). See Section 2 of the Offer to Purchase.

The Depositary for the Offer is:

AMERICAN STOCK TRANSFER & TRUST COMPANY

By Mail:	By Overnight Delivery:	By Hand:
59 Maiden Lane Plaza Level New York, NY 10038	Operations Center 6201 15th Avenue Brooklyn, NY 11219	(9:00 a.m. - 5:00 p.m. New York City Time) 59 Maiden Lane Plaza Level New York, NY 10038
	For Notice of Guaranteed Delivery (for Eligible Institutions only) By Facsimile Transmission: (718) 236-2641 Confirm by Telephone: (800) 937-5449

DELIVERY OF THIS INSTRUMENT TO AN ADDRESS, OR TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE NUMBER, OTHER THAN AS SET FORTH ABOVE, DOES NOT CONSTITUTE A VALID DELIVERY.

        This form is not to be used to guarantee signatures. If a signature on a Letter of Transmittal is required to be guaranteed by an Eligible Institution under the instructions thereto, such signature guarantee must appear in the applicable space provided in the signature box on the Letter of Transmittal.

THE GUARANTEE INCLUDED HEREIN MUST BE COMPLETED.

Ladies and Gentlemen:

        The undersigned represents that the undersigned owns and hereby tenders to Swift Starboard Corporation, a Delaware corporation (the "Purchaser") and a wholly owned subsidiary of Genzyme Corporation, a Massachusetts corporation, upon the terms and subject to the conditions set forth in the Purchaser's Offer to Purchase dated August 13, 2003 (the "Offer to Purchase") and in the related Letter of Transmittal (which, together with any amendments or supplements thereto, collectively constitute the "Offer"), receipt of which is hereby acknowledged, the number of Shares set forth below, all pursuant to the guaranteed delivery procedures set forth in Section 2 of the Offer to Purchase.

Name(s) of Record Holder(s):

Please Print

Address(es):

Zip Code

Daytime Area Code and Tel. No.:

Signature(s):

Number of Shares:

Certificate Nos. (if available):

(Check box if Shares will be tendered by book-entry transfer)

o The Depository Trust Company

Account Number:

Transaction Code No.:

Dated:

GUARANTEE
(Not to be used for signature guarantee)

        The undersigned, a financial institution that is a participant in the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program or the Stock Exchange Medallion Program, hereby guarantees to deliver to the Depositary either the certificates representing the Shares tendered hereby, in proper form for transfer, or a Book-Entry Confirmation (as defined in the Offer to Purchase) with respect to such Shares, in any such case together with a properly completed and duly executed Letter of Transmittal (or a manually signed facsimile thereof), with any required signature guarantees, or an Agent's Message (as defined in the Offer to Purchase), and any other required documents, within three trading days (as defined in the Letter of Transmittal) after the date hereof.

        The Eligible Institution that completes this form must communicate the guarantee to the Depositary and must deliver the Letter of Transmittal (or a manually signed facsimile thereof) and certificates for Shares to the Depositary within the time period shown herein. Failure to do so could result in a financial loss to such Eligible Institution.

Name of Firm:
Address:
Zip Code
Area Code and Tel. No:
Authorized Signature:
Name:
Please Type or Print
Title:
Dated:
NOTE:	DO NOT SEND CERTIFICATES FOR SHARES WITH THIS NOTICE. CERTIFICATES FOR SHARES SHOULD BE SENT WITH YOUR LETTER OF TRANSMITTAL.

EX-99.(A)(4)

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Exhibit 99(a)(4)

Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(Including the Associated Preferred Stock Purchase Rights)
of
SangStat Medical Corporation
at
$22.50 Net Per Share
by
Swift Starboard Corporation
a wholly-owned subsidiary of
Genzyme Corporation

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, SEPTEMBER 10, 2003, UNLESS THE OFFER IS EXTENDED.

August 13, 2003

To Brokers, Dealers, Banks, Trust Companies and Other Nominees:

        We have been appointed by Swift Starboard Corporation, a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation ("Genzyme"), and Genzyme to act as Dealer Manager in connection with the Purchaser's offer to purchase all outstanding shares of common stock, par value $0.001 per share, of SangStat Medical Corporation, a Delaware corporation ("SangStat"), including all preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, by and between SangStat and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares"), at $22.50 per share (the "Offer Price"), net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in the Purchaser's Offer to Purchase dated August 13, 2003 (the "Offer to Purchase"), and in the related Letter of Transmittal (which, together with any amendments or supplements thereto, collectively constitute the "Offer").

        Please furnish copies of the enclosed materials to those of your clients for whom you hold Shares registered in your name or in the name of your nominee.

        Enclosed herewith are copies of the following documents:

        1.     Offer to Purchase dated August 13, 2003;

        2.     Letter of Transmittal to be used by stockholders of SangStat in accepting the Offer;

        3.     Letter to Stockholders of SangStat from the Chairman of the Board, President and Chief Executive Officer of SangStat accompanied by SangStat's Solicitation/Recommendation Statement on Schedule 14D-9;

        4.     A printed form of letter that may be sent to your clients for whose account you hold Shares in your name or in the name of a nominee, with space provided for obtaining such client's instructions with regard to the Offer;

        5.     Notice of Guaranteed Delivery with respect to Shares;

        6.     Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9; and

        7.     Return envelope addressed to American Stock Transfer & Trust Company, as Depositary.

The Offer is conditioned upon, among other things, (a) there being validly tendered and not withdrawn prior to the expiration of the Offer that number of shares, which, together with any shares owned by Genzyme, the Purchaser and Genzyme's other subsidiaries, represents more than 50% of the total number of shares then outstanding on a fully diluted basis, (b) the expiration or termination of the requisite waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, (c) the expiration or termination of the applicable waiting period under Germany's Act Against Restraints of Competition, and (d) any clearances or approvals required under applicable pre-merger notification laws or regulations of other foreign jurisdictions having been obtained. The Offer is also subject to other conditions described in the Offer to Purchase. The Offer is not conditioned upon Genzyme or the Purchaser obtaining funding.

        We urge you to contact your clients promptly. Please note that the Offer and withdrawal rights will expire at 12:00 midnight, New York City time, on Wednesday, September 10, 2003, unless extended.

        The Offer is being made pursuant to the Agreement and Plan of Merger dated as of August 4, 2003 (the "Merger Agreement"), among Genzyme, the Purchaser and SangStat pursuant to which, following the consummation of the Offer and the satisfaction or waiver of certain conditions, the Purchaser will be merged with and into SangStat, with the surviving entity becoming a wholly-owned subsidiary of Genzyme (the "Merger"). At the effective time of the Merger, each outstanding Share (other than Shares owned by Genzyme, the Purchaser, SangStat or stockholders, if any, who are entitled to and properly exercise appraisal rights under Delaware law) will be converted into the right to receive the price per Share paid pursuant to the Offer in cash, without interest thereon, as set forth in the Merger Agreement and described in the Offer to Purchase. The Merger Agreement provides that the Purchaser may assign any or all of its rights and obligations (including the right to purchase Shares in the Offer) to Genzyme or any wholly owned subsidiary of Genzyme, or Genzyme and one or more wholly owned subsidiaries of Genzyme, but no such assignment shall relieve the Purchaser of its obligations under the Merger Agreement.

        The Board of Directors of SangStat unanimously recommends that the stockholders of SangStat accept the Offer and tender their Shares pursuant to the Offer and that the stockholders of SangStat adopt the Merger Agreement, if such adoption is required. The Board of Directors of SangStat, by a unanimous vote, (1) approved the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Offer and the Merger, and declared that the Merger Agreement is advisable and (2) determined that the terms of the Offer and the Merger are fair to, and in the best interests of, SangStat and its stockholders.

        In all cases, payment for Shares accepted for payment pursuant to the Offer will be made only after timely receipt by the Depositary of (a) the certificates for such Shares, together with a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, and any required signature guarantees, or (b) in the case of a transfer effected pursuant to the book-entry transfer procedures described in Section 2 of the Offer to Purchase, a Book-Entry Confirmation (as defined in the Offer to Purchase) and either a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, and any required signature guarantees, or an Agent's Message (as defined in the Offer to Purchase) and any other required documents. Under no circumstances will interest be paid on the purchase price of the Shares to be paid by the Purchaser, regardless of any extension of the Offer or any delay in making such payment.

        Neither the Purchaser nor Genzyme will pay any fees or commissions to any broker or dealer or other person (other than the Dealer Manager and the Information Agent, as described in Section 16 of the Offer to Purchase) for soliciting tenders of Shares pursuant to the Offer. You will be reimbursed by the Purchaser upon request for customary mailing and handling expenses incurred by you in forwarding the enclosed Offer materials to your customers.

        Questions and requests for additional copies of the enclosed material may be directed to the Information Agent or the Dealer Manager at their addresses and telephone numbers set forth on the back cover of the enclosed Offer to Purchase.

Very truly yours,

CREDIT SUISSE FIRST BOSTON LLC

        NOTHING CONTAINED HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL RENDER YOU OR ANY OTHER PERSON THE AGENT OF THE PURCHASER, GENZYME, THE DEPOSITARY OR THE INFORMATION AGENT OR AUTHORIZE YOU OR ANY OTHER PERSON TO GIVE ANY INFORMATION OR MAKE ANY REPRESENTATION ON BEHALF OF ANY OF THEM WITH RESPECT TO THE OFFER NOT CONTAINED IN THE OFFER TO PURCHASE OR THE LETTER OF TRANSMITTAL.

The Information Agent for the Offer is:

501 Madison Avenue, 20th Floor
New York, NY 10022
Banks and Brokers Call Collect: (212) 750-5833
All Others Call Toll Free: (888) 750-5834

The Dealer Manager for the Offer is:

Credit Suisse First Boston LLC
Eleven Madison Avenue
New York, NY 10010-3629
Call Toll Free: (800) 881-8320

QuickLinks

Exhibit 99(a)(4)

EX-99.(A)(5)

Exhibit 99(a)(5)

Offer to Purchase for Cash
All Outstanding Shares of Common Stock
(Including the Associated Preferred Stock Purchase Rights)
of
SangStat Medical Corporation
at
$22.50 Net Per Share
by
Swift Starboard Corporation
a wholly-owned subsidiary of
Genzyme Corporation

        THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, SEPTEMBER 10, 2003, UNLESS THE OFFER IS EXTENDED.

        August 13, 2003

To Our Clients:

        Enclosed for your consideration is an Offer to Purchase dated August 13, 2003 (the "Offer to Purchase") and the related Letter of Transmittal (which, together with amendments or supplements thereto, collectively constitute the "Offer") relating to the Offer by Swift Starboard Corporation, a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation ("Genzyme"), to purchase all outstanding shares of common stock, par value $0.001 per share, of SangStat Medical Corporation, a Delaware corporation ("SangStat"), including all preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, by and between SangStat and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares"), upon the terms and subject to the conditions set forth in the Offer. Also enclosed is the Letter to Stockholders of SangStat from the Chairman of the Board, President and Chief Executive Officer of SangStat accompanied by SangStat's Solicitation/Recommendation Statement on Schedule 14D-9.

        WE (OR OUR NOMINEES) ARE THE HOLDER OF RECORD OF SHARES HELD BY US FOR YOUR ACCOUNT. A TENDER OF SUCH SHARES CAN BE MADE ONLY BY US AS THE HOLDER OF RECORD AND PURSUANT TO YOUR INSTRUCTIONS. THE LETTER OF TRANSMITTAL ACCOMPANYING THIS LETTER IS FURNISHED TO YOU FOR YOUR INFORMATION ONLY AND CANNOT BE USED TO TENDER SHARES HELD BY US FOR YOUR ACCOUNT.

        We request instructions as to whether you wish to tender all or any of the Shares held by us for your account pursuant to the terms and conditions set forth in the Offer.

        Your attention is directed to the following:

           1.  The offer price is $22.50 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions of the Offer.

           2.  The Offer is being made for all outstanding Shares.

           3.  The Offer is being made pursuant to the Agreement and Plan of Merger dated as of August 4, 2003 (the "Merger Agreement"), among Genzyme, the Purchaser and SangStat pursuant to which, following the consummation of the Offer and the satisfaction or waiver of certain conditions, the Purchaser will be merged with and into SangStat, with the surviving entity becoming a wholly-owned subsidiary of Genzyme (the "Merger"). At the effective time of the Merger, each outstanding Share (other than Shares owned by Genzyme, the Purchaser, SangStat or stockholders, if any, who are

entitled to and properly exercise appraisal rights under Delaware law) will be converted into the right to receive the price per Share paid pursuant to the Offer in cash, without interest, as set forth in the Merger Agreement and described in the Offer to Purchase. The Merger Agreement provides that the Purchaser may assign any or all of its rights and obligations (including the right to purchase Shares in the Offer) to Genzyme, any wholly-owned subsidiary of Genzyme, or Genzyme and one or more wholly-owned subsidiaries of Genzyme, but no such assignment shall relieve the Purchaser of its obligations under the Merger Agreement.

           4.  The Board of Directors of SangStat unanimously recommends that the stockholders of SangStat accept the Offer and tender their Shares pursuant to the Offer and that the stockholders of SangStat adopt the Merger Agreement, if such adoption is required. The Board of Directors of SangStat, by a unanimous vote, (1) approved the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Offer and the Merger, and declared that the Merger Agreement is advisable and (2) determined that the terms of the Offer and the Merger are fair to, and in the best interests of, SangStat and its stockholders.

           5.  THE OFFER AND WITHDRAWAL RIGHTS EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON WEDNESDAY, SEPTEMBER 10, 2003 (THE "EXPIRATION DATE"), UNLESS THE OFFER IS EXTENDED BY THE PURCHASER, IN WHICH EVENT THE TERM "EXPIRATION DATE" SHALL MEAN THE LATEST TIME AT WHICH THE OFFER, AS SO EXTENDED BY THE PURCHASER, WILL EXPIRE.

6.  The Offer is conditioned upon, among other things, (a) there being validly tendered and not withdrawn prior to the expiration of the Offer that number of Shares which, together with any Shares owned by Genzyme, the Purchaser and Genzyme's other subsidiaries, represents more than 50% of the total number of Shares then outstanding on a fully-diluted basis, (b) the expiration or termination of the requisite waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, (c) the expiration or termination of the applicable waiting period under Germany's Act Against Restraints of Competition, and (d) any clearances or approvals required under applicable pre-merger notification laws or regulations of other foreign jurisdictions having been obtained. The Offer is also subject to other conditions described in the Offer to Purchase. The Offer is not conditioned upon Genzyme or the Purchaser obtaining funding.

           7.  Any stock transfer taxes applicable to a sale of Shares to the Purchaser will be borne by the Purchaser, except as otherwise provided in Instruction 6 of the Letter of Transmittal.

           8.  Tendering stockholders will not be obligated to pay brokerage fees or commissions to the Dealer Manager, the Depositary or the Information Agent or, except as set forth in Instruction 6 of the Letter of Transmittal, transfer taxes on the sale of Shares to the Purchaser pursuant to the Offer. However, federal income tax backup withholding at a rate of 28% may be required, unless an exemption applies or unless the required taxpayer identification information is provided. See Instruction 9 of the Letter of Transmittal.

        If you wish to have us tender all or any of the Shares held by us for your account, please so instruct us by completing, executing, detaching and returning to us the instruction form below. An envelope to return your instructions to us is enclosed. If you authorize the tender of your Shares, all such Shares will be tendered unless otherwise specified on the instruction form. YOUR INSTRUCTIONS SHOULD BE FORWARDED TO US IN AMPLE TIME TO PERMIT US TO SUBMIT A TENDER ON YOUR BEHALF PRIOR TO THE EXPIRATION DATE.

        In all cases, payment for Shares accepted for payment pursuant to the Offer will be made only after timely receipt by American Stock Transfer & Trust Company (the "Depositary") of (a) the certificates for such Shares, together with a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed, and any required signature guarantees, or (b) in the case of a transfer effected pursuant to the book-entry transfer procedures described in Section 2 of the Offer to Purchase, a Book-Entry Confirmation (as defined in the Offer to Purchase) and either a Letter of Transmittal (or a manually signed facsimile thereof), properly completed and duly executed,

and any required signature guarantees, or an Agent's Message (as defined in the Offer to Purchase) and any other required documents. UNDER NO CIRCUMSTANCES WILL INTEREST BE PAID ON THE PURCHASE PRICE OF THE SHARES TO BE PAID BY THE PURCHASER, REGARDLESS OF ANY EXTENSION OF THE OFFER OR ANY DELAY IN MAKING SUCH PAYMENT.

        The Offer is not being made to (nor will tenders be accepted from or on behalf of) holders of Shares in any jurisdiction in which the making of the Offer or the acceptance thereof would not be in compliance with the laws of such jurisdiction.

INSTRUCTION FORM WITH RESPECT TO THE
OFFER TO PURCHASE FOR CASH
ALL OUTSTANDING SHARES OF COMMON STOCK
(INCLUDING THE ASSOCIATED PREFERRED STOCK PURCHASE RIGHTS)
OF
SANGSTAT MEDICAL CORPORATION

        The undersigned acknowledge(s) receipt of your letter, the Offer to Purchase of Swift Starboard Corporation, dated August 13, 2003 (the "Offer to Purchase") and the related Letter of Transmittal relating to shares of common stock, par value $0.001 per share, of SangStat Medical Corporation, a Delaware corporation ("SangStat"), including the associated preferred stock purchase rights issued pursuant to the Rights Agreement, dated as of August 14, 1995, by and between SangStat and Equiserve Trust Company, N.A., as amended from time to time (together, the "Shares").

        This will instruct you to tender the number of Shares indicated below held by you for the account of the undersigned, on the terms and subject to the conditions set forth in the Offer to Purchase and related Letter of Transmittal.

Number of Shares to be Tendered:* Shares

Signature(s)

Please Type or Print Name(s)

Type or Print Address(es)

Area Code and Telephone Number

Taxpayer Identification or Social Security Number

Dated: , 2003

* Unless otherwise indicated, it will be assumed that all your Shares are to be tendered.

EX-99.(A)(6)

Exhibit 99(a)(6)

GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
NUMBER ON SUBSTITUTE FORM W-9

        Guidelines for Determining the Proper Identification Number to Give the Payer.    Social Security numbers and individual taxpayer identification numbers have nine digits separated by two hyphens: e.g., 000-00-0000. Employer identification numbers have nine digits separated by only one hyphen: e.g., 00-0000000. The table below will help determine the number to give the payer.

For this type of account:		Give the SOCIAL SECURITY Number (or individual taxpayer identification number) of—	For this type of account:		Give the EMPLOYER INDENTIFICATION number of—
1.	An individual's account	The individual	6.	A valid trust, estate, or pension trust	The legal entity (Do not furnish the identifying number of the personal representative or trustee unless the legal entity itself is not designated in the account title.)(4)
2.	Two or more individuals (joint account)	The actual owner of the account or, if combined funds, the first individual on the account(1)	7.	Corporate account	The corporation
3.	Custodian account of a minor (Uniform Gift to Minors Act)	The minor(2)	8.	Association, club, religious, charitable, educational, or other tax-exempt organization account	The organization
4.	a. The usual revocable savings trust account (grantor is also trustee)	The grantor-trustee(1)	9.	Partnership account held in the name of the business	The partnership
	b. So-called trust account that is not a legal or valid trust under State law	The actual owner(1)	10.	A broker or registered nominee	The broker or nominee
5.	Sole proprietorship account	The owner(3)	11.	Account with the Department of Agriculture in the name of a public entity (such as a State or local government, school district, or prison) that receives agricultural program payments	The public entity

(1)

List first and circle the name of the person whose number you furnish. If only one person on a joint account has a social security number, that person's number must be furnished.

(2)

Circle the minor's name and furnish the minor's social security number.

(3)

You must show the name of the individual owner, but you may also enter your business or "doing business as" name. You may use either your social security number or your employer identification number (if you have one).

(4)

List first and circle the name of the legal trust, estate, or pension trust.

Note: If no name is circled when there is more than one name, the number will be considered to be that of the first name listed.

Obtaining a Number

        If you don't have a taxpayer identification number, obtain Form SS-5, Application for a Social Security Number Card, Form SS-4, Application for Employer Identification Number, or Form W-4, Application for Individual Taxpayer Identification Number at the local office of the Social Security Administration or the Internal Revenue Service and apply for a number.

Payees Exempt from Backup Withholding

        Backup withholding is not required on any payments made to the following payees:

1.

An organization exempt from tax under section 501(a), any IRA, or a custodial account under section 403(b)(7) if the account satisfies the requirements of section 401(f)(2);

2.

The United States or any of its agencies or instrumentalities;

3.

A state, the District of Columbia, a possession of the United States, or any of their political subdivisions or instrumentalities;

4.

A foreign government or any of its political subdivisions, agencies, or instrumentalities; or

5.

An international organization or any of its agencies or instrumentalities.

        Other payees that may be exempt from backup withholding include:

6.

A corporation;

7.

A foreign central bank of issue;

8.

A dealer in securities or commodities required to register in the United States, the District of Columbia, or a possession of the United States;

9.

A futures commission merchant registered with the Commodity Futures Trading Commission;

10.

A real estate investment trust;

11.

An entity registered at all times during the tax year under the Investment Company Act of 1940;

12.

A common trust fund operated by a bank under section 584(a);

13.

A financial institution;

14.

A middleman known in the investment community as a nominee or custodian; or

15.

A trust exempt from tax under section 664 or described in section 4947.

        The chart below shows types of payments that may be exempt from backup withholding. The chart applies to the exempt recipients listed above, 1 through 15.

If the payment is for…	THEN the payment is exempt for…
Interest and dividend payments	All exempt recipients except for 9
Broker transactions	Exempt recipients 1 through 13. Also, a person registered under the Investment Advisers Act of 1940 who regularly acts as a broker
Barter exchange transactions and patronage dividends	Exempt recipients 1 through 5
Payments over $600 required to be reported and direct sales over $5,000(1)	Generally, exempt recipients 1 through 7(2)

(1)

See Form 1099-MISC, Miscellaneous Income, and its instructions.

(2)

However, the following payments made to a corporation (including gross proceeds paid to an attorney under section 6045(f), even if the attorney is a corporation) and reportable on Form 1099-MISC are not exempt from backup withholding: medical and health care payments, attorneys' fees, and payments for services paid by a Federal executive agency.

        EXEMPT PAYEES DESCRIBED ABOVE SHOULD FILE SUBSTITUTE FORM W-9 TO AVOID POSSIBLE ERRONEOUS BACKUP WITHHOLDING. FILE THIS FORM WITH THE PAYER, FURNISH YOUR TAXPAYER IDENTIFICATION NUMBER, WRITE "EXEMPT" ON THE FACE OF THE FORM, AND RETURN IT TO THE PAYER. IF THE PAYMENTS ARE INTEREST, DIVIDENDS, OR PATRONAGE DIVIDENDS, ALSO SIGN AND DATE THE FORM.

Privacy Act Notice

        Section 6109 requires most recipients of dividend, interest, or other payments to give taxpayer identification numbers to payers who must report the payments to the IRS. The IRS uses the numbers for identification purposes and to help verify the accuracy of your tax return. The IRS may also provide this information to the Department of Justice for civil and criminal obligations and to cities, states, and the District of Columbia to carry out their tax laws. The IRS may also disclose the information to other countries under a tax treaty, or to Federal and State agencies to enforce Federal non-tax criminal laws and to combat terrorism. A payer must be given the numbers whether or not recipients are required to file tax returns. Payers must generally withhold 28% of taxable interest, dividend, and certain other payments from a payee who does not furnish a taxpayer identification number to the payer. Certain penalties may also apply.

Penalties

(1)

Penalty for Failure to Furnish Taxpayer Identification Number.—If you fail to furnish your taxpayer identification number to a payer, you are subject to a penalty of $50 for each such failure unless your failure is due to reasonable cause and not to willful neglect.

(2)

Civil Penalty for False Information with Respect to Withholding.—If you make a false statement with no reasonable basis which results in no imposition of backup withholding, you are subject to a penalty of $500.

(3)

Criminal Penalty for Falsifying Information.—Falsifying certifications or affirmations may subject you to criminal penalties including fines and/or imprisonment.

FOR ADDITIONAL INFORMATION CONTACT YOUR TAX CONSULTANT OR THE INTERNAL REVENUE SERVICE.

EX-99.(A)(10)

This announcement is neither an offer to purchase nor a solicitation of an offer
to sell Shares (as defined below). The Offer (as defined below) is made solely
by the Offer to Purchase, dated August 13, 2003, and the related Letter of
Transmittal, and is being made to all holders of Shares. The Offer is not being
made to (nor will tenders be accepted from or on behalf of) holders of Shares in
any jurisdiction in which the making of the Offer or the acceptance thereof
would not be in compliance with the laws of such jurisdiction. In those
jurisdictions where the applicable laws require that the Offer be made by a
licensed broker or dealer, the Offer shall be deemed to be made on behalf of the
Purchaser by Credit Suisse First Boston LLC ("Credit Suisse First Boston") or by
one or more registered brokers or dealers licensed under the laws of such
jurisdiction.

                      Notice of Offer to Purchase for Cash
                     All Outstanding Shares of Common Stock
             (Including Associated Preferred Stock Purchase Rights)
                                       of
                          SangStat Medical Corporation
                                       at
                              $22.50 Net Per Share
                                       by
                           Swift Starboard Corporation
                          a wholly-owned subsidiary of
                               Genzyme Corporation

Swift Starboard Corporation, a Delaware corporation ("Purchaser") and a
wholly-owned subsidiary of Genzyme Corporation, a Massachusetts corporation
("Genzyme"), is offering to purchase all outstanding shares of common stock, par
value $0.001 per share, including associated preferred stock purchase rights
issued in respect of such shares (the "Shares"), of SangStat Medical
Corporation, a Delaware corporation ("SangStat"), at a price of $22.50 per
Share, net to the seller in cash, without interest thereon, upon the terms and
subject to the conditions set forth in the Offer to Purchase, dated August 13,
2003 (the "Offer to Purchase"), and in the related Letter of Transmittal (which,
together with any amendments or supplements thereto from time to time,
constitute the "Offer"). Tendering stockholders whose Shares are registered in
their names and who tender directly to American Stock Transfer & Trust Company
(the "Depositary") will not be obligated to pay brokerage fees or commissions
or, except as set forth in Instruction 6 of the Letter of Transmittal, transfer
taxes on the sale of Shares pursuant to the Offer. Stockholders who hold their
Shares through banks or brokers should check with such institutions as to
whether they charge any service fees.

The purpose of the Offer is to enable Genzyme, through Purchaser, to acquire
control of SangStat and to effect the first step in the acquisition of all of
the outstanding Shares. Following consummation of the Offer, Purchaser intends
to effect the merger described below.



THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
TIME, ON WEDNESDAY, SEPTEMBER 10, 2003, UNLESS THE OFFER IS EXTENDED.

The Offer is conditioned upon, among other things, (i) there being validly
tendered and not withdrawn prior to the expiration of the Offer that number of
Shares which, together with any Shares owned by Genzyme, Purchaser and Genzyme's
other subsidiaries, represents more than 50% of the total number of Shares then
outstanding on a fully-diluted basis (the "Minimum Condition"), (ii) the
expiration or termination of the applicable waiting period under the
Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, (iii) the
expiration or termination of the applicable waiting period under Germany's Act
Against Restraints on Competition, and (iv) any applicable clearances or
approvals required under applicable pre-merger notification laws or regulations
of other foreign jurisdictions having been obtained. The Offer also is subject
to other conditions described in the Offer to Purchase. The Offer is not
conditioned upon Genzyme or Purchaser obtaining funding.

The Offer is being made pursuant to an Agreement and Plan of Merger, dated as of
August 4, 2003 (the "Merger Agreement"), among Genzyme, Purchaser and SangStat.
The Merger Agreement provides for, among other things, the commencement of the
Offer by Purchaser and further provides that after the purchase of Shares
pursuant to the Offer, subject to the satisfaction or waiver of certain
conditions, Purchaser will be merged with and into SangStat (the "Merger"), with
SangStat surviving the Merger as a wholly-owned subsidiary of Genzyme. At the
effective time of the Merger, each outstanding Share (other than Shares held in
treasury by SangStat, Shares held by Genzyme or Purchaser or Shares held by
stockholders who have properly exercised their appraisal rights under Delaware
law) will be converted into the right to receive $22.50 per Share (or such
higher price as may be paid in the Offer), net to the seller in cash, without
interest thereon.

The Board of Directors of SangStat unanimously recommends that the stockholders
of SangStat accept the Offer and tender their Shares pursuant to the Offer and
that the stockholders of SangStat adopt the Merger Agreement, if such adoption
is required. The Board of Directors of SangStat, by a unanimous vote, (1)
approved the Merger Agreement and the transactions contemplated by the Merger
Agreement, including the Offer and the Merger, and declared that the Merger
Agreement is advisable and (2) determined that the terms of the Offer and the
Merger are fair to, and in the best interests of, SangStat and its stockholders.

If by 12:00 midnight, New York City time, on September 10, 2003 (or any later
time to which Purchaser, subject to the terms of the Merger Agreement, extends
the period of time during which the Offer is open (the "Expiration Date")) (i)
all the conditions to the Offer have not been satisfied or waived, Purchaser may
extend the Offer, (ii) any rule, regulation or interpretation of the Securities
and Exchange Commission requires that the Offer be extended, Purchaser may
extend the Offer for such required period, or (iii) all of the conditions to
Purchaser's obligations to accept Shares for payment are satisfied or



waived, but there shall not have been validly tendered and not withdrawn that
number of Shares necessary to permit the Merger without a meeting of SangStat
stockholders, Purchaser may extend (or re-extend) the Offer for an aggregate
period not to exceed 20 business days. Any announcement of an extension will be
made no later than 9:00 a.m., New York City time, on the next business day after
the previously scheduled Expiration Date.

If at the Expiration Date, all of the conditions of the Offer have been
satisfied or waived and Purchaser has accepted for payment all Shares tendered
in the Offer, Purchaser may provide an additional period of three to 20 business
days subsequent to the Offer in which stockholders would be able to tender
Shares not tendered in the Offer (a "Subsequent Offering Period"). Purchaser
does not currently intend to provide a Subsequent Offering Period, although it
reserves the right to do so in its sole discretion.

For purposes of the Offer, Purchaser will be deemed to have accepted for
payment, and thereby purchased, Shares validly tendered and not properly
withdrawn, if and when Purchaser gives oral or written notice to the Depositary
of Purchaser's acceptance for payment of such Shares. Upon the terms and subject
to the conditions of the Offer, payment for Shares purchased pursuant to the
Offer will be made by deposit of the purchase price therefor with the
Depositary, which will act as agent for tendering stockholders for the purpose
of receiving payment from Purchaser and transmitting payment to tendering
stockholders whose Shares have been accepted for payment. In all cases, payment
for Shares accepted for payment pursuant to the Offer will be made only after
timely receipt by the Depositary of (i) the certificates for such Shares,
together with a Letter of Transmittal (or a manually signed facsimile thereof),
properly completed and duly executed, and any required signature guarantees, or
(ii) in the case of a book-entry transfer, a Book-Entry Confirmation (as defined
in the Offer to Purchase) and either a Letter of Transmittal (or a manually
signed facsimile thereof), properly completed and duly executed, and any
required signature guarantees, or an Agent's Message (as defined in the Offer to
Purchase), and (iii) any other required documents. Under no circumstances will
interest be paid on the purchase price for tendered Shares, regardless of any
extension of or amendment to the Offer or any delay in paying for such Shares.

Except as otherwise provided in the Offer to Purchase, tenders of Shares made
pursuant to the Offer are irrevocable. Shares tendered pursuant to the Offer may
be withdrawn pursuant to the procedures set forth in the Offer to Purchase at
any time prior to the Expiration Date and, unless theretofore accepted for
payment as provided in the Offer to Purchase, at any time on or after October
13, 2003. For a withdrawal to be effective, a written or facsimile transmission
notice of withdrawal must be timely received by the Depositary at one of its
addresses set forth on the back cover of the Offer to Purchase and must specify
the name of the person having tendered the Shares to be withdrawn, the number of
Shares to be withdrawn and the name of the registered holder of the Shares to be
withdrawn, if different from the name of the person who tendered the Shares. If
certificates for Shares have been delivered or otherwise identified to the
Depositary, then, prior to the physical release of such certificates, the serial
numbers shown on such certificates must be submitted to the Depositary and,
unless such Shares have been



tendered by an Eligible Institution (as defined in the Offer to Purchase), any
and all signatures on the notice of withdrawal must be guaranteed by an Eligible
Institution. If Shares have been tendered pursuant to the book-entry transfer
procedures set forth in the Offer to Purchase, any notice of withdrawal must
also specify the name and number of the account at the Book-Entry Transfer
Facility (as defined in the Offer to Purchase) to be credited with the withdrawn
Shares and otherwise comply with the Book-Entry Transfer Facility's procedures.
All questions as to the form and validity (including time of receipt) of notices
of withdrawal will be determined by Purchaser, in its sole discretion, whose
determination shall be final and binding. Withdrawals of Shares may not be
rescinded. Any Shares properly withdrawn will be deemed not validly tendered for
purposes of the Offer, but may be retendered at any subsequent time prior to the
Expiration Date by following any of the procedures described in the Offer to
Purchase. In the event Purchaser provides a Subsequent Offering Period following
the Offer, no withdrawal rights will apply to the Shares tendered during such
Subsequent Offering Period or to Shares tendered in the Offer and accepted for
payment.

Generally, the receipt of cash in exchange for Shares pursuant to the Offer or
the Merger will be a taxable transaction for U.S. federal income tax purposes
and may also be a taxable transaction under applicable state, local or foreign
tax laws. All stockholders are urged to consult their own tax advisors to
determine the particular tax consequences to them, including the application and
effect of any state, local or foreign income and other tax laws, of the Offer
and the Merger.

SangStat has provided Purchaser with SangStat's stockholder lists and security
position listings for the purpose of disseminating the Offer to holders of
Shares. The Offer to Purchase and the related Letter of Transmittal and other
relevant materials will be mailed to record holders of Shares and will be
furnished to brokers, dealers, banks, trust companies and similar persons whose
names, or the names of whose nominees, appear on the stockholder lists or, if
applicable, who are listed as participants in a clearing agency's security
position listing, for subsequent transmittal to beneficial owners of Shares.

The information required to be disclosed by paragraph (d) (1) of Rule 14d-6
under the Securities Exchange Act of 1934, as amended, is contained in the Offer
to Purchase and is incorporated herein by reference.

The Offer to Purchase and the related Letter of Transmittal contain important
information about the Offer and should be read carefully in their entirety
before any decision is made with respect to the Offer.

Questions and requests for assistance may be directed to the Information Agent
or Credit Suisse First Boston and requests for copies of the Offer to Purchase,
the Letter of Transmittal and all other tender offer documents may be directed
to the Information Agent as set forth below, and copies will be furnished
promptly at Purchaser's expense. Neither Purchaser nor Genzyme will pay any fees
or commissions to any broker or dealer or other person (other than the
Depositary, Credit Suisse First Boston and the Information Agent) for soliciting
tenders of Shares pursuant to the Offer.



                     The Information Agent for the Offer is:
                           Innisfree M&A Incorporated
                         501 Madison Avenue, 20th Floor
                            New York, New York 10022
                 Banks and Brokers Call Collect: (212) 750-5833
                    All Others Call Toll-Free: (888) 750-5834

                      The Dealer Manager for the Offer is:
                           Credit Suisse First Boston
                              Eleven Madison Avenue
                          New York, New York 10010-3629
                         Call Toll Free: (800) 881-8320


August 13, 2003

EX-99.(A)(11)

MILBERG WEISS BERSHAD
    HYNES & LERACH LLP
WILLIAM S. LERACH (68581)
DARREN J. ROBBINS (168593)
401 B Street, Suite 1700
San Diego, CA 92101
Telephone: 619/231-1058
619/231-7423 (fax)
  
Attorneys for Plaintiff ENDORSED
FILED
ALAMEDA COUNTY
  
AUG 07 2003
  
CLERK OF THE SUPERIOR COURT
By Shantal R. Vinuya, Deputy

SUPERIOR COURT OF THE STATE OF CALIFORNIA

COUNTY OF ALAMEDA

ROCCO PIGNONE, On Behalf of Himself and All Others Similarly Situated,	) )	VIA FAX
	)	Case No. RG03110801
Plaintiff,	)
	)	CLASS ACTION
vs.	)
SANGSTAT MEDICAL CORPORATION,	) )	COMPLAINT BASED UPON SELF-DEALING AND BREACH OF FIDUCIARY DUTY
JEAN-JACQUES BIENAIMÉ,	)
FREDRIC J. FELDMAN,	)
CORINNE H. LYLE,	)
RICHARD D. MURDOCK,	)
ANDREW J. PERLMAN,	)
HOLLINGS C. RENTON, III	)
and DOES 1-25, inclusive,	)
	)
Defendants.	)
	)

COMPLAINT BASED UPON SELF-DEALING AND BREACH OF FIDUCIARY DUTY

        Plaintiff, by his attorneys, alleges as follows:

SUMMARY OF THE ACTION

        1.     This is a stockholder class action brought by plaintiff on behalf of the holders of SangStat Medical Corporation ("SangStat" or the "Company") common stock against SangStat's directors arising out of their attempts to provide certain SangStat insiders and directors preferential treatment in connection with their efforts to complete the sale of SangStat to Genzyme Corporation (the "Acquisition"). This action seeks equitable relief only.

        2.     In pursuing the unlawful plan to sell SangStat, each of the defendants violated applicable law by directly breaching and/or aiding the other defendants' breaches of their fiduciary duties of loyalty, due care, independence, good faith and fair dealing.

        3.     In fact, instead of attempting to obtain the highest price reasonably available for SangStat for its shareholders, the individual defendants spent substantial effort tailoring the structural terms of the Acquisition to meet the specific needs of Genzyme Corporation ("Genzyme").

        4.     The proposed sale is wrongful, unfair and harmful to SangStat's public stockholders, and represents an effort by defendants to aggrandize their own financial position and interests at the expense of and to the detriment of Class members. The Acquisition is an attempt to deny plaintiff and the other members of the Class their rights while usurping the same for the benefit of Genzyme on unfair terms. Moreover, defendants must be required to:

•

Disclose the benefits to the Company expected to be derived from the contract associated with the development of RDP58 it is finalizing (with a company whose identity has been concealed). Each of the defendants have or should have the knowledge of the value of this contract. It's value, terms and financial impact remain concealed from shareholders.



•

Rescind any and all "payoff" agreements and stock option grants which will accelerate as a result of this transaction.



•

Withdraw their consent to the sale of SangStat and allow the shares to trade freely—without impediments.



•

Act independently so that the interests of SangStat's public stockholders will be protected, including, but not limited to, the retention of truly independent advisors and/or the appointment of a truly independent Special Committee.



•

Adequately ensure that no conflicts of interest exist between defendants' own interests and their fiduciary obligation to maximize stockholder value or, if such conflicts exist, to ensure that all conflicts be resolved in the best interests of SangStat's public stockholders.

        5.     In essence, the proposed Acquisition is the product of a hopelessly flawed process that was designed to ensure the sale of SangStat to one buying group, and one buying group only, on terms preferential to Genzyme and to subvert the interests of plaintiff and the other public stockholders of SangStat.

JURISDICTION AND VENUE

        6.     This Court has jurisdiction over the cause of action asserted herein pursuant to the California Constitution, Article VI, §10, because this case is a cause not given by statute to other trial courts.

        7.     This Court has jurisdiction over defendants because they conduct business in California and/or are citizens of California. Defendant SangStat's headquarters are located at 6300 Dumbarton Circle, Fremont, California. This action is not removable.

1

        8.     Venue is proper in this Court because the conduct at issue took place and had an effect in this County.

PARTIES

        9.     Plaintiff Rocco Pignone is, and at all times relevant hereto was, a shareholder of SangStat.

        10.   Defendant SangStat is a Delaware corporation. SangStat is a global pharmaceutical company focused on immunology and working to discover, develop and market therapeutic products in immunology, transplantation medicine, hematology/oncology and autoimmune disorders.

        11.   Defendant Jean-Jacques Bienaime ("Bienaime") is a director of SangStat.

        12.   Defendant Fredric J. Feldman ("Feldman") is a director of SangStat.

        13.   Defendant Corinne H. Lyle ("Lyle") is a director of SangStat.

        14.   Defendant Richard D. Murdock ("Murdock") is Chairman of the Board, President and Chief Executive Officer of SangStat.

        15.   Defendant Andrew J. Perlman ("Perlman") is a director of SangStat.

        16.   Defendant Hollings C. Renton, III ("Renton") is a director of SangStat.

        17.   The defendants named above in ¶¶11-16 are sometimes collectively referred to herein as the "Individual Defendants."

        18.   The true names and capacities of defendants sued herein under California Code of Civil Procedure §474 as Does 1 through 25, inclusive, are presently not known to plaintiff, who therefore sues these defendants by such fictitious names. Plaintiff will seek to amend this Complaint and include these Doe defendants' true names and capacities when they are ascertained. Each of the fictitiously named defendants is responsible in some manner for the conduct alleged herein and for the injuries suffered by the Class.

DEFENDANTS' FIDUCIARY DUTIES

        19.   In accordance with their duties of loyalty, care and good faith, the defendants, as directors and/or officers of SangStat, are obligated to refrain from:

        (a)   participating in any transaction where the directors' or officers' loyalties are divided;

        (b)   participating in any transaction where the directors or officers receive or are entitled to receive a personal financial benefit not equally shared by the public shareholders of the corporation; and/or

        (c)   unjustly enriching themselves at the expense or to the detriment of the public shareholders.

        20.   Plaintiff alleges herein that the Individual Defendants, separately and together, in connection with the sale of SangStat, violated the fiduciary duties owed to plaintiff and the other public shareholders of SangStat, including their duties of loyalty, good faith and independence, insofar as they stood on both sides of the transaction and engaged in self-dealing and obtained for themselves personal benefits, including personal financial benefits not shared equally by plaintiff or the Class.

        21.   Because the Individual Defendants have breached their duties of loyalty, good faith and independence in connection with the sale of SangStat, the burden of proving the inherent or entire fairness of the Acquisition, including all aspects of its negotiation and structure, is placed upon the Individual Defendants as a matter of law.

2

CLASS ACTION ALLEGATIONS

        22.   Plaintiff brings this action on his own behalf and as a class action pursuant to California Code of Civil Procedure §382 on behalf of all holders of SangStat stock who are being and will be harmed by defendants' actions described below (the "Class"). Excluded from the Class are defendants herein and any person, firm, trust, corporation, or other entity related to or affiliated with any defendant.

        23.   This action is properly maintainable as a class action.

        24.   The Class is so numerous that joinder of all members in impracticable. According to SangStat's Securities and Exchange Commission ("SEC") filings, there were more than 26.5 million shares of SangStat's common stock outstanding.

        25.   There are questions of law and fact which are common to the Class and which predominate over questions affecting any individual Class member. The common questions include, inter alia, the following:

        (a)   whether defendants have breached their fiduciary duties of undivided loyalty, independence or due care with respect to plaintiff and the other members of the Class in connection with the Acquisition;

        (b)   whether the Individual Defendants are engaging in self-dealing in connection with the Acquisition;

        (c)   whether the Individual Defendants are unjustly enriching themselves and other insiders or affiliates of SangStat;

        (d)   whether defendants have breached any of their other fiduciary duties to plaintiff and the other members of the Class in connection with the Acquisition, including the duties of good faith, diligence, honesty and fair dealing;

        (e)   whether the defendants, in bad faith and for improper motives, have impeded or erected barriers to discourage other offers for the Company or its assets; and

        (f)    whether plaintiff and the other members of the Class would suffer irreparable injury were the transactions complained of herein consummated.

        26.   Plaintiff's claims are typical of the claims of the other members of the Class and plaintiff does not have any interests adverse to the Class.

        27.   Plaintiff is an adequate representative of the Class, has retained competent counsel experienced in litigation of this nature and will fairly and adequately protect the interests of the Class.

        28.   The prosecution of separate actions by individual members of the Class would create a risk of inconsistent or varying adjudications with respect to individual members of the Class which would establish incompatible standards of conduct for the party opposing the Class.

        29.   Plaintiff anticipates that there will be no difficulty in the management of this litigation. A class action is superior to other available methods for the fair and efficient adjudication of this controversy.

        30.   Defendants have acted on grounds generally applicable to the Class with respect to the matters complained of herein, thereby making appropriate the relief sought herein with respect to the Class as a whole.

3

BACKGROUND TO THE PROPOSED ACQUISITION

        31.   SangStat is a global biopharmaceutical company focused on immunology and working to discover, develop and market therapeutic products in immunology, transplantation medicine, hematology/oncology and autoimmune disorders.

        32.   On August 4, 2003, defendants issued a press release on PR Newswire entitled, "Genzyme to Acquire SangStat Medical Corporation; Gains Leading Transplant Antibody Product, Strengthens Immunology Pipeline." The press release stated in part:

        Genzyme Corporation and SangStat Medical Corporation announced today that they have reached an agreement under which Genzyme will acquire SangStat in an all cash transaction valued at $22.50 per outstanding share, or approximately $600 million. The transaction is expected to be dilutive to Genzyme's GAAP earnings due to amortization through 2004. Excluding amortization, it is expected to be neutral to slightly accretive to Genzyme's earnings through 2004, and accretive beyond that time.

        With this transaction, Genzyme is acquiring a profitable and growing company with a leading antibody product used in organ transplantation, a well-respected U.S. and European field organization, and a strong development program with a significant pipeline in immune suppression and immunology. This pipeline is complementary to Genzyme's own work in immune-mediated diseases, such a sclerodema, multiple sclerosis, and pulmonary fibrosis. SangStat's lead product, Thymoglobulin® (anti-thymocyte globulin), is indicated in the United States for the treatment of acute rejection in patients with a renal transplant. The company reported revenues of $120 million in 2002, generating earnings of $0.24 per share.

        "This is a strong strategic fit for Genzyme, which adds a growing product, a strong pipeline, and a skilled team that nicely complements our ongoing programs in the high-potential area of immune mediated diseases," said Henri A. Termeer, chairman and chief executive officer, Genzyme Corporation. "Thymoglobulin is an excellent product that has the potential to transform the way transplant teams manage the care of their patients. We will use our combined resources and expertise to expand its areas of use and broaden its availability throughout the world."

        Thymoglobulin is an immunosuppressive polyclonal antibody product that suppresses certain types of immune cells responsible for acute organ rejection in transplant patients. Clinical studies have demonstrated that using Thymoglobulin to treat an acute rejection episode in a renal transplant patient may reverse the rejection episode. Acute rejection is the most common immunologic complication in transplant patients.

        In many European countries, Thymoglobulin is indicated for induction and treatment in solid organ transplants. In a number of these countries, it is indicated for the treatment of graft versus host disease, and for the treatment of aplastic anemia. In Japan and certain other countries, SangStat markets Lymphoglobuline® (anti-Thymocyte-globulin, equine) for the treatment of aplastic anemia and the prevention and treatment of graft rejection. Global sales of these products have grown steadily since Thymoglobulin was launched in the United States in 1999, reaching $77.4 million in 2002.

SELF-DEALING

        33.   By reason of their positions with SangStat, the Individual Defendants are in possession of non-public information concerning the financial condition and prospects of SangStat, and especially the true value and expected increased future value of SangStat and its assets, which they have not disclosed to SangStat's public stockholders. Moreover, despite their duty to maximize shareholder value, the defendants have clear and material conflicts of interest and are acting to better their own interests at the expense of SangStat's public shareholders.

4

        34.   The proposed sale is wrongful, unfair and harmful to SangStat's public stockholders, and represents an effort by defendants to aggrandize their own financial position and interests at the expense of and to the detriment of Class members. The Acquisition is an attempt to deny plaintiff and the other members of the Class their rights while usurping the same for the benefit of Genzyme on unfair terms.

        35.   In light of the foregoing, the Individual Defendants must, as their fiduciary obligations require:

•

Disclose the benefits to the Company expected to be derived for the contract associated with the development of RDP58 it is finalizing (with a company whose identity has been concealed). Each of the defendants have or should have knowledge of the value of this contract. It's value, terms and financial impact remain concealed from shareholders.



•

Rescind any and all "payoff" agreements and stock option grants which will accelerate as a result of this transaction.



•

Withdraw their consent to the sale of SangStat and allow the shares to trade freely—without impediments.



•

Act independently so that the interests of SangStat's public stockholders will be protected, including, but not limited to, the retention of truly independent advisors and/or the appointment of a truly independent Special Committee.



•

Adequately ensure that no conflicts of interest exist between defendants' own interests and their fiduciary obligation to maximize stockholder value or, if such conflicts exist, to ensure that all conflicts be resolved in the best interests of SangStat's public stockholders.

        36.   The Individual Defendants have also approved the Acquisition so that it transfers 100% of SangStat's revenues and profits to Genzyme, thus all of SangStat's operations will now accrue to the benefit of Genzyme.

CAUSE OF ACTION

Claim for Breach of Fiduciary Duties

        37.   Plaintiff repeats and realleges each allegation set forth herein.

        38.   The defendants have violated fiduciary duties of care, loyalty, candor and independence owed under Delaware law to the public shareholders of SangStat and have acted to put their personal interests ahead of the interests of SangStat's shareholders.

        39.   By the acts, transactions and courses of conduct alleged herein, defendants, individually and acting as a part of a common plan, are attempting to advance their interests at the expense of plaintiff and other members of the Class.

        40.   The Individual Defendants have violated their fiduciary duties by entering into a transaction with Genzyme without regard to the fairness of the transaction to SangStat's shareholders. Defendant SangStat directly breached and/or aided and abetted the other defendants' breaches of fiduciary duties owed to plaintiff and the other holders of SangStat stock.

        41.   As demonstrated by the allegations above, the Individual Defendants failed to exercise the care required, and breached their duties of loyalty, good faith, candor and independence owed to the shareholders of SangStat because, among other reasons:

        (a)   they failed to properly value SangStat; and

5

        (b)   they ignored or did not protect against the numerous conflicts of interest resulting from their own interrelationships or connection with the Acquisition.

        42.   Because the Individual Defendants dominate and control the business and corporate affairs of SangStat, and are in possession of private corporate information concerning SangStat's assets, business and future prospects, there exists an imbalance and disparity of knowledge and economic power between them and the public shareholders of SangStat which makes it inherently unfair for them to pursue any proposed transaction wherein they will reap disproportionate benefits.

        43.   By reason of the foregoing acts, practices and course of conduct, the defendants have failed to exercise ordinary care and diligence in the exercise of their fiduciary obligations toward plaintiff and the other members of the Class.

        44.   As a result of the actions of defendants, plaintiff and the Class will suffer irreparable injury as a result of defendants' self dealing.

        45.   Unless enjoined by this Court, the defendants will continue to breach their fiduciary duties owed to plaintiff and the Class, and may consummate the proposed Acquisition which will exclude the Class from its fair share of SangStat's valuable assets and businesses, and/or benefit them in the unfair manner complained of herein, all to the irreparable harm of the Class, as aforesaid.

        46.   Defendants are engaging in self-dealing, are not acting in good faith toward plaintiff and the other members of the Class, and have breached and are breaching their fiduciary duties to the members of the Class.

        47.   Unless the proposed Acquisition is enjoined by the Court, defendants will continue to breach their fiduciary duties owed to plaintiff and the members of the Class, will not engage in arm's-length negotiations on the Acquisition terms, and will not supply to SangStat's minority stockholders sufficient information to enable them to cast informed votes on the proposed Acquisition and may consummate the proposed Acquisition, all to the irreparable harm of the members of the Class.

        48.   Plaintiff and the members of the Class have no adequate remedy at law. Only through the exercise of this Court's equitable powers can plaintiff and the Class be fully protected from the immediate and irreparable injury which defendants' actions threaten to inflict.

PRAYER FOR RELIEF

        WHEREFORE, plaintiff demands preliminary and permanent injunctive relief in his favor and in favor of the Class and against defendants as follows:

        A.    Declaring that this action is properly maintainable as a class action;

        B.    Declaring and decreeing that the Acquisition agreement was entered into in breach of the fiduciary duties of the defendants and is therefore unlawful and unenforceable;

        C.    Enjoining defendants, their agents, counsel, employees and all persons acting in concert with them from consummating the Acquisition, unless and until the Company adopts and implements a procedure or process to obtain the highest possible price for shareholders;

        D.    Directing the Individual Defendants to exercise their fiduciary duties to obtain a transaction which is in the best interests of SangStat's shareholders;

        E.    Rescinding, to the extent already implemented, the Acquisition or any of the terms thereof;

        F.     Awarding plaintiff the costs and disbursements of this action, including reasonable attorneys' and experts' fees; and

6

        G.    Granting such other and further equitable relief as this Court may deem just and proper.

DATED: August 7, 2003	MILBERG WEISS BERSHAD     HYNES & LERACH LLP WILLIAM S. LERACH DARREN J. ROBBINS
	/s/  DARREN J. ROBBINS DARREN J. ROBBINS
	401 B Street, Suite 1700 San Diego, CA 92101 Telephone: 619/231-1058 619/231-7423 (fax)
	Attorneys for Plaintiff

7

EX-99.(A)(12)

                                                               Exhibit 99(a)(12)



FOR IMMEDIATE RELEASE               MEDIA CONTACT:            INVESTOR CONTACT:
Aug. 13, 2003                       Dan Quinn                 Sally Curley
                                    (617) 591-5849            (617) 591-7140

    GENZYME COMMENCES TENDER OFFER FOR ACQUISITION OF SANGSTAT MEDICAL CORP.

         CAMBRIDGE, Mass - Genzyme Corp. (Nasdaq: GENZ) announced today that it
has commenced, through a wholly-owned subsidiary, a cash tender offer for all of
the outstanding shares of Sangstat Medical Corp. (Nasdaq: SANG) for $22.50 per
share.

         Genzyme and SangStat announced on Aug. 4 that they had reached an
agreement under which Genzyme would acquire SangStat in an all cash tender
offer. SangStat, a profitable and growing company, will bring to Genzyme a
leading antibody product used in organ transplantation, and a significant
product development program in immune-mediated diseases.

         Both SangStat's board of directors and a special merger committee of
Genzyme's board of directors have unanimously approved the agreement. SangStat's
board unanimously determined the terms of the agreement are fair to, and in the
best interests of, SangStat and its shareholders.

         Genzyme's offer is subject to certain conditions, including the tender
of at least a majority of all outstanding shares on a fully diluted basis, and
the expiration or termination of the waiting periods under the Hart-Scott-Rodino
Antitrust Improvements Act of 1976, and any other applicable pre-merger
notification laws or regulations of foreign jurisdictions.


                                     (more)




         The offer and withdrawal rights will expire after 12 midnight on Sept.
10, 2003, unless the offer is extended. The information agent for the offer is
Innisfree M&A Incorporated. Banks and brokers can call Innisfree collect at
(212) 750-5833. All others can call toll free at 888-750-5834.

         Genzyme Corporation is a global biotechnology company dedicated to
making a major positive impact on the lives of people with serious diseases. The
company's broad product portfolio is focused on rare genetic disorders, renal
disease, and osteoarthritis, and includes an industry-leading array of
diagnostic products and services. Genzyme's commitment to innovation continues
today with research into novel approaches to cancer, heart disease, and other
areas of unmet medical need. Genzyme's 5,300 employees worldwide serve patients
in more than 80 countries.

         SangStat Medical Corporation is a global biotechnology company focused
on immunology and working to discover, develop and market high value therapeutic
products in the autoimmune, hematology/oncology and immunosuppression areas.
SangStat's U.S. headquarters are in Fremont, California. SangStat also maintains
a strong European presence, including direct sales and marketing forces in
France, Germany, Italy, Spain, and the UK, and distributors throughout the rest
of the world. SangStat's stock is traded on the NASDAQ under the symbol "SANG".

         This announcement is not a recommendation, offer to purchase or a
solicitation of an offer to sell shares of common stock of SangStat Medical
Corporation. On August 13, 2003, Genzyme Corporation and Swift Starboard
Corporation, a wholly-owned subsidiary of Genzyme Corporation, commenced a
tender offer for all of the outstanding shares of common stock (including
associated preferred stock purchase rights) of SangStat Medical Corporation at
$22.50 per share. This tender offer is scheduled to

                                     (more)




expire at 12:00 midnight, New York City time, on September 10, 2003, unless it
is extended as provided in the related offer to purchase. Genzyme Corporation
and Swift Starboard Corporation have filed with the Securities and Exchange
Commission a tender offer statement on Schedule TO and related exhibits,
including the offer to purchase, letter of transmittal, and other related
documents. Shareholders should read the offer to purchase and the tender offer
statement on Schedule TO and related exhibits because they contain important
information. Shareholders can obtain these documents free of charge from the
Securities and Exchange Commission's web site at www.sec.gov, or from Genzyme
Corporation by directing a request to Genzyme Corporation, One Kendall Square,
Cambridge, MA 02139, Attention: Investor Relations.

         This press release contains forward-looking statements, including
statements about: the potential acquisition of SangStat by Genzyme and the
potential benefits of the anticipated acquisition. These statements are subject
to risks and uncertainties that could cause actual results to differ materially
from those projected in these forward-looking statements. These risks and
uncertainties include, among others: the willingness of SangStat shareholders to
tender their shares in the tender offer and the number and timing of shares
tendered; the receipt of regulatory and third party consents to the extent
required for the acquisition; the results of preclinical and clinical trials of
SangStat's product candidates and their actual safety and efficacy as therapies
for immune-mediated diseases; the actual timing and content of submissions to
and decisions made by regulatory authorities regarding SangStat's product
candidates; and the risks and uncertainties described in reports filed by
Genzyme and SangStat with the Securities and Exchange Commission under the
Securities Exchange Act of 1934, as amended, including without limitation
Exhibit 99.2 to Genzyme's 2002 Annual Report on Form 10-K, as amended, and under
the heading "Risk Factors" in SangStat's 2002 Annual Report on Form 10-K. We
caution investors not to place undue reliance on the forward-looking statements
contained in this press release. These statements speak only as of the date of
this press release, and we undertake no obligation to update or revise the
statements, risks or reasons. All forward looking statements are expressly
qualified in their entirety by this cautionary statement.

         Genzyme(R) is a registered trademark of Genzyme Corporation.
SangStat(R) is a registered trademark of SangStat Medical Corporation. All
rights reserved.


                                      # # #

 Genzyme's press releases and other company information are available at
www.genzyme.com and by calling Genzyme's investor information line at
1-800-905-4369 within the United States or 1-703-797-1866 outside the United
States.

EX-99.(B)

                      AMENDED AND RESTATED CREDIT AGREEMENT

                                      AMONG

                              GENZYME CORPORATION,

                     THE SUBSIDIARY GUARANTORS PARTY HERETO,

                            THE LENDERS PARTY HERETO,

                                       AND

                              FLEET NATIONAL BANK,
                            AS ADMINISTRATIVE AGENT,

                               ABN AMRO BANK N.V.,
                              AS SYNDICATION AGENT

                         AND FIRST UNION NATIONAL BANK,
                             AS DOCUMENTATION AGENT



                            DATED: DECEMBER 14, 2000









                               TABLE OF CONTENTS

                                                                                                             
SECTION 1.  DEFINITIONS AND ACCOUNTING MATTERS--------------------------------------------------------------------2

   1.1        Certain Defined Terms-------------------------------------------------------------------------------2
   1.2        Accounting Terms and Determinations----------------------------------------------------------------21
   1.3        Types of Loans/Facilities--------------------------------------------------------------------------21

SECTION 2.  COMMITMENTS, LOANS, NOTES AND PREPAYMENTS------------------------------------------------------------21

   2.1        Revolving Credit Loans-----------------------------------------------------------------------------21
   2.2        Borrowings of Revolving Credit Loans---------------------------------------------------------------23
   2.3        Changes of Commitments-----------------------------------------------------------------------------23
   2.4        Commitment Fee-------------------------------------------------------------------------------------23
   2.5        Lending Offices------------------------------------------------------------------------------------24
   2.6        Several Obligations; Remedies Independent----------------------------------------------------------24
   2.7        Notes----------------------------------------------------------------------------------------------24
   2.8        Optional Prepayments and Conversions or Continuations of Loans-------------------------------------25

SECTION 3.  PAYMENTS OF PRINCIPAL AND INTEREST-------------------------------------------------------------------25

   3.1        Repayment of Loans---------------------------------------------------------------------------------25
   3.2        Interest-------------------------------------------------------------------------------------------25

SECTION 4.  PAYMENTS; PRO RATA TREATMENT; COMPUTATIONS; ETC.-----------------------------------------------------26

   4.1        Payments-------------------------------------------------------------------------------------------26
   4.2        Pro Rata Treatment---------------------------------------------------------------------------------28
   4.3        Computations---------------------------------------------------------------------------------------28
   4.4        Minimum Amounts------------------------------------------------------------------------------------28
   4.5        Certain Notices------------------------------------------------------------------------------------28
   4.6        Non-Receipt of Funds by the Administrative Agent; Delinquent Lenders-------------------------------30
   4.7        Sharing of Payments, Etc.--------------------------------------------------------------------------31

SECTION 5.  YIELD PROTECTION, ETC.-------------------------------------------------------------------------------32

   5.1        Additional Costs-----------------------------------------------------------------------------------32
   5.2        Limitation on Types of Loans-----------------------------------------------------------------------34
   5.3        Illegality-----------------------------------------------------------------------------------------35
   5.4        Treatment of Affected Loans------------------------------------------------------------------------35
   5.5        Compensation---------------------------------------------------------------------------------------36
   5.6        Rate Selection-------------------------------------------------------------------------------------37

SECTION 6.  GUARANTEE--------------------------------------------------------------------------------------------37

   6.1        Guarantee------------------------------------------------------------------------------------------37
   6.2        Obligations Unconditional--------------------------------------------------------------------------38
   6.3        Reinstatement--------------------------------------------------------------------------------------39
   6.4        Subrogation----------------------------------------------------------------------------------------39
   6.5        Remedies-------------------------------------------------------------------------------------------39
   6.6        Continuing Guarantee-------------------------------------------------------------------------------39
   6.7        Rights of Contribution-----------------------------------------------------------------------------39
   6.8        Limitation on Guarantee Obligations----------------------------------------------------------------40









                                                                                                              
SECTION 7.  CONDITIONS PRECEDENT---------------------------------------------------------------------------------40

   7.1        Initial Loan---------------------------------------------------------------------------------------40
   7.2        Initial and Subsequent Extensions of Credit--------------------------------------------------------43

SECTION 8.  REPRESENTATIONS AND WARRANTIES-----------------------------------------------------------------------43

   8.1        Existence------------------------------------------------------------------------------------------43
   8.2        Financial Condition--------------------------------------------------------------------------------44
   8.3        Litigation-----------------------------------------------------------------------------------------44
   8.4        No Breach------------------------------------------------------------------------------------------44
   8.5        Action---------------------------------------------------------------------------------------------45
   8.6        Approvals------------------------------------------------------------------------------------------45
   8.7        Use of Credit--------------------------------------------------------------------------------------45
   8.8        ERISA----------------------------------------------------------------------------------------------45
   8.9        Taxes----------------------------------------------------------------------------------------------46
   8.10       Investment Company Act-----------------------------------------------------------------------------46
   8.11       Public Utility Holding Company Act-----------------------------------------------------------------46
   8.12       Borrowing Agreements and Liens---------------------------------------------------------------------46
   8.13       Compliance with Laws Including Environmental and Safety Matters------------------------------------47
   8.14       Subsidiaries, Etc.---------------------------------------------------------------------------------47
   8.15       Title to Assets; Etc.------------------------------------------------------------------------------47
   8.16       Intellectual Property Rights-----------------------------------------------------------------------48
   8.17       Year 2000 Compliance-------------------------------------------------------------------------------48
   8.18       True and Complete Disclosure-----------------------------------------------------------------------48
   8.19       Initial Acquisition Disclosure---------------------------------------------------------------------49

SECTION 9.  COVENANTS OF THE COMPANY-----------------------------------------------------------------------------49

   9.1        Financial Statements Etc.--------------------------------------------------------------------------49
   9.2        Litigation-----------------------------------------------------------------------------------------51
   9.3        Existence, Etc.------------------------------------------------------------------------------------51
   9.4        Insurance------------------------------------------------------------------------------------------52
   9.5        Prohibition of Fundamental Changes-----------------------------------------------------------------52
   9.6        Limitation on Liens--------------------------------------------------------------------------------54
   9.7        Indebtedness---------------------------------------------------------------------------------------56
   9.8        Investments----------------------------------------------------------------------------------------57
   9.9        Financial Covenants--------------------------------------------------------------------------------57
   9.10       Lines of Business----------------------------------------------------------------------------------57
   9.11       Use of Proceeds------------------------------------------------------------------------------------57
   9.12       Certain Obligations Respecting Company and Subsidiaries--------------------------------------------58
   9.13       Additional Subsidiary Guarantors-------------------------------------------------------------------58
   9.14       Subordinated Debt----------------------------------------------------------------------------------59

SECTION 10.  EVENTS OF DEFAULT-----------------------------------------------------------------------------------59

SECTION 11.  THE AGENTS------------------------------------------------------------------------------------------62

   11.1       Appointment, Powers and Immunities.----------------------------------------------------------------62
   11.2       Reliance by Agents---------------------------------------------------------------------------------63
   11.3       Defaults-------------------------------------------------------------------------------------------63









                                                                                                              
   11.4       Rights as a Lender---------------------------------------------------------------------------------64
   11.5       Indemnification------------------------------------------------------------------------------------64
   11.6       Non-Reliance on Agents and Other Lenders-----------------------------------------------------------64
                             -
   11.7       Failure to Act-------------------------------------------------------------------------------------65
   11.8       Resignation or Removal of Agents-------------------------------------------------------------------65
   11.9       Consents under Other Loan Documents----------------------------------------------------------------65

SECTION 12.  MISCELLANEOUS---------------------------------------------------------------------------------------66

   12.1     Waiver-----------------------------------------------------------------------------------------------66
   12.2     Notices----------------------------------------------------------------------------------------------66
   12.3     Expenses, Etc.---------------------------------------------------------------------------------------66
   12.4     Indemnification--------------------------------------------------------------------------------------67
   12.5     Amendments, Etc.-------------------------------------------------------------------------------------68
   12.6     Successors and Assigns-------------------------------------------------------------------------------68
   12.7     Assignments and Participations-----------------------------------------------------------------------68
   12.8     Survival---------------------------------------------------------------------------------------------70
   12.9     Captions---------------------------------------------------------------------------------------------70
   12.10    Counterparts-----------------------------------------------------------------------------------------70
   12.11    Governing Law; Submission to Jurisdiction------------------------------------------------------------70
   12.12    Waiver of Jury Trial---------------------------------------------------------------------------------71
   12.13    Confidentiality--------------------------------------------------------------------------------------71
   12.14    Compliance with Usury Laws---------------------------------------------------------------------------72
   12.15    Replacement Note-------------------------------------------------------------------------------------72
   12.16    Transitional Arrangements----------------------------------------------------------------------------72



Schedules:


    Schedule 8.3        Litigation

    Schedule 8.12A      Credit Agreements, Indentures, Guarantees,
                        Letters of Credit, Etc.

    Schedule 8.12B      Liens Securing Indebtedness

    Schedule 8.14       Subsidiaries


Exhibits:

    Exhibit A           Form of Three-Year Facility Revolving Credit Note

    Exhibit B           Form of 364-Day Facility Revolving Credit Note

    Exhibit C           Form of Legal Opinion

    Exhibit D           Form of Compliance Certificate

    Exhibit E           Form of Joinder Agreement

    Exhibit F           Form of Notice of Assignment

    Exhibit G           Form of Pledge Agreement

    Exhibit H           Form of Notice of Borrowing

    Exhibit I           Form of Notice of Conversion/Continuation



    Exhibit J           Form of Notice of Prepayment

    Exhibit K           Form of Termination of Prior Credit Agreement







                                 CREDIT AGREEMENT

         CREDIT AGREEMENT ("Agreement" or "Credit Agreement") dated as of
December 14, 2000 among and between:

         GENZYME CORPORATION, a corporation duly organized and validly
existing under the laws of The Commonwealth of Massachusetts (together with
its permitted successors and assigns, the "Company");

         Each of the Subsidiaries of the Company identified under the caption
"SUBSIDIARY GUARANTORS" on the signature pages hereto or that may hereafter
become a "Subsidiary Guarantor" pursuant to Section 9.13 hereof (together
with its permitted successors and assigns, individually, a "SUBSIDIARY
GUARANTOR" and, collectively, the "SUBSIDIARY GUARANTORS" and, together with
the Company, the "OBLIGORS");

         Each of the lenders identified under the caption "LENDERS" on the
signature pages hereto or that may hereafter become a "Lender" pursuant to
Section 12.7(b) hereof (together with its successors and permitted assigns,
individually, a "LENDER" and, collectively, the "Lenders"); and

         FLEET NATIONAL BANK ("FLEET") as administrative agent for the
Lenders (in such capacity, together with the successors in such capacity, the
"ADMINISTRATIVE AGENT");

         ABN AMRO Bank N.V. ("ABN AMRO") as syndication agent for the Lenders
(in such capacity, together with the successors in such capacity, the
"Syndication Agent"); and

         First Union National Bank ("First Union") as documentation agent for
the Lenders (in such capacity, together with the successors in such capacity,
the "Documentation Agent" and together with the Administrative Agent and the
Syndication Agent, the "AGENT" or "AGENTS").

         The Company has requested that the Lenders extend credit to the
Company in an aggregate principal or stated amount not exceeding
$500,000,000.00; and

         To induce the Lenders to extend such credit, the Obligors, the
Lenders and the Agents propose to enter into this Agreement pursuant to
which, INTER ALIA, (1) the Lenders will make loans to the Company and (2)
each Subsidiary Guarantor will guarantee the credit so extended to the
Company. Each of the Obligors expects to derive benefit, directly or
indirectly, from the credit so extended to the Company, both in its separate
capacity and as a member of the integrated group, since the successful
operation of each of the Obligors is dependent on the continued successful
performance of the functions of the integrated group as a whole.

         Accordingly, the parties hereto agree as follows:

                                       -1-



Section 1.        DEFINITIONS AND ACCOUNTING MATTERS.

         1.1. CERTAIN DEFINED TERMS. As used herein, the following terms
shall have the following meanings (all terms defined in this Section 1.1 or
in other provisions of this Agreement in the singular to have the same
meanings when used in the plural and VICE VERSA).

         "ACCOUNTS RECEIVABLE" shall mean, on any date, the net amount of
accounts receivable of Company and its Consolidated Subsidiaries, excluding
any such accounts which are more than 120 days old, after deducting all
returns, discounts and allowances thereon and reserves relating thereto,
determined in accordance with GAAP.

         "ADJUSTED LIBO RATE" shall mean, for any LIBOR Loan, a rate per
annum (rounded upwards, if necessary, to the nearest 1/100 of 1%) determined
by the Administrative Agent to be equal to the rate of interest specified in
the definition of "LIBO Rate" in this Section 1.1 for the Interest Period for
such Loan divided by 1 minus the Reserve Requirement (if any) for such Loan
for such Interest Period.

         "ADMINISTRATIVE AGENT" shall have the meaning given such term in the
preamble hereto, as it may be amended, modified, or changed from time to time.

         "AFFILIATE" shall mean any Person that directly or indirectly
controls, or is under common control with, or is controlled by a designated
Person and, if such designated Person is an individual, any member of the
immediate family (including parents, spouse, children and siblings) of such
individual and any trust whose principal beneficiary is such individual or
one or more members of such immediate family and any Person who is controlled
by any such member or trust. As used in this definition, "CONTROL"
(including, with its correlative meanings, "CONTROLLED BY" and "UNDER COMMON
CONTROL WITH") shall mean possession, directly or indirectly, of power to
direct or cause the direction of management or policies (whether through
ownership of securities or partnership or other ownership interests, by
contract or otherwise), or that, in any event, any Person that owns directly
or indirectly securities having 33% or more of the voting power for the
election of directors or other governing body of a corporation or 33% or more
of the partnership or other ownership interests of any other Person will be
deemed to control such corporation, partnership or other Person.
Notwithstanding the foregoing, (a) the Company and its Subsidiaries shall not
be Affiliates of each other and (b) neither any Agent nor any Lender shall be
an Affiliate of the Company or any of its Subsidiaries.

         "AGENTS" shall have the meaning given in the preamble hereto, as it
may be amended, modified or changed from time to time.

         "APPLICABLE COMMITMENT FEE RATE" shall mean, for any period set
forth below for each Facility, the percentage set forth below opposite such
period under the caption "APPLICABLE COMMITMENT FEE RATE" and under the
caption for the respective Facility, and "APPLICABLE MARGIN" shall mean, for
any period set forth below for either Type of Loan set forth below, the
percentage set forth below opposite such period under the caption "APPLICABLE
MARGIN" and under the caption for such Type of Loan:

                                       -2-






- ------------------------- ---------------------------------------------- ---------------------------------------------
                                        Applicable Margin                       Applicable Commitment Fee Rate
         Period
- ------------------------- ---------------------------------------------- ---------------------------------------------
                            Prime Rate Loans          LIBOR Loans         Three-Year Facility     364-Day Facility
- ------------------------- ---------------------- ----------------------- ---------------------- ----------------------
                                                                                    
- ------------------------- ---------------------- ----------------------- ---------------------- ----------------------
        Level I                  0.000%                  1.000%                 0.250%                 0.175%
- ------------------------- ---------------------- ----------------------- ---------------------- ----------------------
        Level II                 0.000%                  0.875%                 0.225%                 0.150%
- ------------------------- ---------------------- ----------------------- ---------------------- ----------------------
       Level III                 0.000%                  0.750%                 0.200%                 0.125%
- ------------------------- ---------------------- ----------------------- ---------------------- ----------------------
       Level IV                  0.000%                  0.625%                 0.175%                 0.100%
- ------------------------- ---------------------- ----------------------- ---------------------- ----------------------



PROVIDED, HOWEVER, that:

       (a)      subject to paragraph (b) below, at all times after the first
                Business Day that is six (6) months after the Closing Date
                that outstanding Loans exceed 33% of the aggregate amount of
                the Commitments and as to which Levels I, II or III apply, the
                Applicable Margin for LIBOR Loans shall equal the sum of the
                percentage set forth above opposite such period under the
                caption "LIBOR Loans," PLUS 0.125%;

       (b)      notwithstanding paragraph (a) above, at all times after the
                first Business Day that is six (6) months after the Closing
                Date that outstanding Loans exceed 67% of the aggregate amount
                of the Commitments AND as to which Levels I, II or III apply,
                the Applicable Margin for LIBOR Loans shall equal the sum of
                the percentage set forth above opposite such period under the
                caption "LIBOR Loans," PLUS 0.250%;

       (c)      at all times after the first Business Day that is six (6)
                months after the Closing Date that outstanding Loans exceed
                67% of the aggregate amount of the Commitments AND as to which
                Level IV applies, the Applicable Margin for LIBOR Loans shall
                equal the sum of the percentage set forth above opposite such
                period under the caption "LIBOR Loans," PLUS 0.125%; and

       (d)      at all times prior to and including the first Business Day
                that is six (6) months after the Closing Date (other than any
                period when an Event of Default shall have occurred and be
                continuing):

                (i) the Applicable Margin: (A) for Prime Rate Loans shall mean
                the percentages set forth opposite the designation "Level II
                Period"; and (B) for LIBOR Loans shall mean the sum of (1) the
                percentage set forth in the definition of "Applicable Margin"
                opposite the designation "Level II Period" plus (2)
                one-quarter of one percent (0.25%); and

                (ii) the Applicable Commitment Fee Rate shall be the
                percentage set forth opposite the designation "Level II
                Period".

         "APPLICABLE LENDING OFFICE" shall mean, for each Lender and for each
Type of Loan, the "Lending Office" of such Lender (or of an affiliate of such
Lender) designated for such Type of


                                       -3-


Loan on the signature pages hereof or such other office of such Lender (or of
an affiliate of such Lender) as such Lender may from time to time specify to
the Administrative Agent and the Company as the office by which its Loans of
such Type are to be made and maintained.

         "BANKRUPTCY CODE" shall mean the Federal Bankruptcy Code of 1978, as
amended from time to time.

         "BASLE ACCORD" shall mean the proposals for risk-based capital
framework described by the Basle Committee on Banking Regulations and
Supervisory Practices in its paper entitled "International Convergence of
Capital Measurement and Capital Standards" dated July 1988, as amended,
modified and supplemented and in effect from time to time or any replacement
thereof.

         "BIOMATRIX ACQUISITION" shall mean the transactions contemplated by
the Biomatrix Acquisition Documents.

         "BIOMATRIX ACQUISITION DOCUMENTS" shall mean, individually and
collectively, the Agreement and Plan of Merger dated as of March 6, 2000
among the Company, Seagull Merger Corporation, and Biomatrix, Inc., as
amended by that certain Amendment No. 1 to Agreement and Plan of Merger dated
as of April 17, 2000 among the Company, Seagull Merger Corporation, and
Biomatrix, Inc., that certain Amendment No. 2 to Agreement and Plan of Merger
dated as of August 25, 2000 among the Company, Seagull Merger Corporation,
and Biomatrix, Inc., and that certain Amendment No. 3 to Agreement and Plan
of Merger dated October 25, 2000 among the Company, Seagull Merger
Corporation, and Biomatrix, Inc., Waiver and Consent to Agreement and Plan of
Merger dated as of October 25, 2000 among the Company, Seagull Merger
Corporation, and Biomatrix, Inc., Stockholder Voting Agreement dated as of
March 6, 2000 between the Company and each of Endre A. Balays, Rory B. Riggs,
Janet L. Denlinger and Maxime Seifert, and Stock Option Agreement dated as of
March 6, 2000 by and between the Company and Biomatrix, Inc., together with
all other agreements of transfer as are referred to therein and all side
letters with respect thereto, and all agreements, documents and instruments
executed and/or delivered in connection therewith, as all of the foregoing
now exist or may hereafter be amended, modified, supplemented, extended,
renewed, restated, or replaced.

         "BUSINESS DAY" shall mean (a) any day on which commercial banks are
not authorized or required to close in Boston, Massachusetts and (b) if such
day relates to the giving of notices or quotes in connection with a borrowing
of, a payment or prepayment of principal of or interest on, a Conversion of
or into, or an Interest Period for, a LIBOR Loan or a notice by the Company
with respect to any such borrowing, payment, prepayment, Conversion or
Interest Period, then any day referred to in clause (a) that is also a day on
which dealings in Dollar deposits are carried out in the London interbank
market.

         "CAPITAL EXPENDITURES" shall mean, for any period, expenditures
(including, without limitation, the aggregate amount of Capital Lease
Obligations incurred during such period) made by the Company or any of its
Subsidiaries to acquire or construct fixed assets, plant and equipment
(including renewals, improvements and replacements, but excluding repairs)
during such period computed in accordance with GAAP.

                                       -4-



         "CAPITAL LEASE OBLIGATIONS" shall mean, for any Person, all
obligations of such Person to pay rent or other amounts under a lease of (or
other agreement conveying the right to use) property to the extent such
obligations are required to be classified and accounted for as a capital
lease on a balance sheet of such Person under GAAP, and, for purposes of this
Agreement, the amount of such obligations shall be the capitalized amount
thereof, determined in accordance with GAAP.

         "CAPITAL STOCK" shall mean capital stock of the Company that does
not rank prior, as to the payment of dividends or as to the distribution of
assets upon any voluntary or involuntary liquidation, dissolution or winding
up of the Company, to shares of capital stock of any other class of the
Company.

         "CASH EQUIVALENTS" shall mean any interest bearing investment of
Company and its Wholly Owned Subsidiaries which meets the definition of a
"cash equivalent" under GAAP (i.e., purchased with a remaining maturity of 90
days or less). Such investments shall be at least investment grade (A1/P1 for
commercial paper, BBB or better for bonds and similar investments).

         "CLOSING DATE" the date upon which the initial Loans hereunder are
made.

         "CODE" shall mean the Internal Revenue Code of 1986, as amended from
time to time.

         "COMMITMENTS" shall mean the Revolving Credit Commitments.

         "COMPANY" shall have the meaning given in the preamble, and its
successors and permitted assigns hereunder.

         "COMPLIANCE CERTIFICATE" shall mean the compliance certificate
provided for under Section 9.1(c)(ii) in substantially the form of EXHIBIT D.

         "CONSOLIDATED" shall mean, when used with reference to any term,
that term (or the term "combined" in the case of partnerships, joint ventures
and Affiliates of the Company that are not Subsidiaries) as applied to the
accounts of Company (or any other specified Person) and all of its
Subsidiaries (or other specified Persons) or such of its Subsidiaries as may
be specified, consolidated (or combined) in accordance with GAAP and with
appropriate deductions for minority interests in Subsidiaries, if required by
GAAP.

         "CONSOLIDATED EBITDA" shall mean, for any period, the sum, for the
Company, of the following: (a) Consolidated Operating Income for such period
PLUS (b) depreciation and amortization, but only to the extent deducted in
determining Consolidated Operating Income for such period.

         "CONSOLIDATED DEBT COVERAGE RATIO" shall mean, at any date, the
ratio, for the Company and its Consolidated Subsidiaries, of (a) the sum of
(i) Unrestricted Cash on such date plus (ii) Marketable Investments on such
date to (b) Consolidated Funded Debt on such date.

         "CONSOLIDATED FIXED CHARGE COVERAGE RATIO" shall mean, for any
period, the ratio of (a) the sum of (i) Consolidated EBITDA for such period
LESS (ii) the aggregate amount of Capital

                                       -5-



Expenditures made during such period LESS (iii) the amount of the taxes paid
during such period LESS (iv) the aggregate amount of all Dividend Payments
made during such period PLUS (v) Synthetic Lease Obligations paid during such
period to (b) the sum of (i) all Interest expense for such period PLUS (ii)
Synthetic Lease Obligations paid during such period, PROVIDED, HOWEVER, that
the Company may designate with respect to one project for improvements to new
leased headquarters and with respect to any consecutive fiscal quarters that
clause (ii) above shall consist instead of the aggregate amount of Capital
Expenditures made during such period in excess of the lesser of (x)
$12,000,000; or (y) the aggregate amount incurred by the Company during those
consecutive fiscal quarters for expenditures for such project for
improvements to new leased headquarters for the Company.

         "CONSOLIDATED FUNDED DEBT" shall mean, at any time, the outstanding
balance of all Indebtedness in respect of borrowed money, Capital Lease
Obligations, Synthetic Lease Obligations, letters of credit and trade
acceptances for the Company and its Consolidated Subsidiaries.

         "CONSOLIDATED NET INCOME" shall mean, for any period, net income (or
loss) for the Company and its Consolidated Subsidiaries (determined in
accordance with GAAP), PROVIDED, HOWEVER, that Consolidated Net Income shall
not include amounts included in computing net income (or loss) in respect of
(a) the write-up of assets (other than Marketable Investments) after December
31, 1995 and (b) extraordinary and non-recurring gains or losses.

         "CONSOLIDATED NET WORTH" shall mean, as at any date, the
shareholder's equity of the Company and its Consolidated Subsidiaries.

         "CONSOLIDATED OPERATING INCOME" shall mean, for any period, the
Consolidated Net Income of the Company for such period, PROVIDED, HOWEVER,
that, to the extent the following items have been included in determining
Consolidated Net Income, they shall NOT be considered in computing
Consolidated Operating Income: provision for income taxes, interest expense,
equity in the operating results of unconsolidated subsidiaries (including
partnerships, joint ventures and Affiliates of the Company but only to the
extent that such results represent noncash, nonoperating items) and other
non-operating, non-cash items including, but not limited to, write-off of
acquired technology or acquired, in-process research and development which,
in accordance with GAAP, must be charged to income.

         "CONSOLIDATED QUICK RATIO" shall mean, at any date, the ratio, for
the Company and its Consolidated Subsidiaries, of (a) the sum of (i)
Unrestricted Cash on such date PLUS (ii) Marketable Investments on such date
PLUS (iii) Accounts Receivable on such date to (b) the sum of (i) Current
Liabilities on such date PLUS (ii) current Synthetic Lease Obligations.

         "CONSOLIDATED TANGIBLE ASSETS" shall mean, at any date, all assets
of the Borrower and its Consolidated Subsidiaries other than Intangible
Assets.

         "CONTINUE", "CONTINUATION" and "CONTINUED" shall refer to the
continuation pursuant to Section 2.8 hereof of a LIBOR Loan from one Interest
Period to the next Interest Period.

                                       -6-



         "CONVERT", "CONVERSION" and "CONVERTED" shall refer to a conversion
pursuant to Section 2.8 hereof of one Type of Loans into another Type of
Loans, which may be accompanied by the transfer by a Lender (at its sole
discretion, but subject to Section 5.1(d) hereof) of a Loan from one
Applicable Lending Office to another.

         "CURRENT LIABILITIES" shall mean any liability that in accordance
with GAAP would be classified as such.

         "DEFAULT" shall mean an Event of Default or an event that with
notice or lapse of time or both would become an Event of Default.

         "DIVIDEND PAYMENT" shall mean dividends (in cash, Property or
obligations) on, or other payments or distributions on account of, or the
setting apart of money for a sinking or other analogous fund for, or the
purchase, redemption, retirement or other acquisition of, any shares of any
class of stock of, or any partnership or other equity interest issued by, the
Company or of any warrants, options or other rights to acquire the same (or
to make any payments to any Person, such as "phantom stock" payments, where
the amount thereof is calculated with reference to the fair market or equity
value of the Company or any of its Subsidiaries), but excluding dividends
payable solely in shares of common stock of the Company.

         "DOLLARS" and "$" shall mean lawful money of the United States of
America.

         "ENVIRONMENTAL CLAIM" shall mean, with respect to any Person, any
written or oral notice, claim, demand or other communication (collectively, a
"claim") by any other Person alleging or asserting such Person's liability
for investigatory costs, cleanup costs, governmental response costs, damages
to natural resources or other Property, personal injuries, fines or penalties
arising out of, based on or resulting from (a) the presence, or Release into
the environment, of any Hazardous Material at any location, whether or not
owned by such Person, or (b) circumstances forming the basis of any
violation, or alleged violation, of any Environmental Law. The term
"Environmental Claim" shall include, without limitation, any claim by any
governmental authority for enforcement, cleanup, removal, response, remedial
or other actions or damages pursuant to any applicable Environmental Law, and
any claim by any third party seeking damages, contribution, indemnification,
cost recovery, compensation or injunctive relief resulting from the presence
of Hazardous Materials or arising from alleged injury or threat of injury to
the environment.

         "ENVIRONMENTAL LAWS" shall mean any and all present and future
Federal, state, local and foreign laws, rules or regulations, and any orders
or decrees, in each case as now or hereafter in effect, relating to the
regulation or protection of the environment or to emissions, discharges,
releases or threatened releases of pollutants, contaminants or toxic or
hazardous substances or wastes into the indoor or outdoor environment,
including, without limitation, ambient air, soil, surface water, ground
water, wetlands, land or subsurface strata, or otherwise relating to the
manufacture, processing, distribution, use, treatment, storage, disposal,
transport or handling of pollutants, contaminants or toxic or hazardous
substances or wastes.

         "ERISA" shall mean the Employee Retirement Income Security Act of
1974, as amended from time to time.

                                       -7-



         "ERISA AFFILIATE" shall mean any corporation or trade or business
that is a member of any group of organizations (a) described in Section
414(b) or (c) of the Code of which the Company is a member and (b) solely for
purposes of potential liability under Section 302(c)(11) of ERISA and Section
412(c)(11) of the Code and the lien created under Section 302(f) of ERISA and
Section 412(n) of the Code, described in Section 414(m) or (o) of the Code of
which the Company is a member.

         "EVENT OF DEFAULT" shall have the meaning assigned to such term in
Section 10 hereof.

         "FACILITY" shall have the meaning given in Section 1.3 hereof.

         "FEDERAL FUNDS RATE" shall mean, for any day, the rate per annum
(rounded upwards, if necessary, to the nearest 1/100 of 1%) equal to the
weighted average of the rates on overnight Federal funds transactions with
members of the Federal Reserve System arranged by Federal funds brokers on
such day, as published by the Federal Reserve Bank of New York on the
Business Day next succeeding such day, PROVIDED that (a) if the day for which
such rate is to be determined is not a Business Day, the Federal Funds Rate
for such day shall be such rate on such transactions on the next preceding
Business Day as so published on the next succeeding Business Day and (b) if
such rate is not so published for any Business Day, the Federal Funds Rate
for such Business Day shall be the average rate charged to the Administrative
Agent on such Business Day on such transactions as determined by the
Administrative Agent.

         "FUNDAMENTAL CHANGE" shall mean any of the following:

                  (i) a "person" or "group" (within the meaning of Sections
13(d) and 14(d)(2) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act")), becoming the "beneficial owner" (as defined in Rule 13d-3
under the Exchange Act) of Voting Shares of the Company entitled to exercise
more than 50% of the total voting power of all outstanding Voting Shares of
the Company (including any right to acquire Voting Shares that are not then
outstanding of which such person or group is deemed the beneficial owner); or

                  (ii) a change in the Board of Directors in which the
individuals who constituted the Board of Directors at the beginning of the
two-year period immediately preceding such change (together with any other
director whose election by the Board of Directors or whose nomination for
election by the shareholders of the Company was approved by a vote of at
least two-thirds of the directors then in office who either were directors at
the beginning of such period or whose election or nomination for election was
previously so approved) cease for any reason to constitute a majority of the
directors then in office; or

                  (iii) any consolidation of the Company with, or merger of
the Company into, any other Person, any merger of another Person into the
Company, or any sale or transfer of all or substantially all of the assets of
the Company to another Person (other than (w) a merger which does not result
in any reclassification, conversion, exchange or cancellation of outstanding
shares of Capital Stock, (x) a merger which is effected solely to change the
jurisdiction of incorporation of the Company, (y) any consolidation with or
merger of the Company into a Wholly Owned Subsidiary of the Company, or any
sale or transfer by the Company of all or substantially all of its assets to
one or more of its Wholly Owned Subsidiaries, in any one transaction or a
series of transactions, provided, in any such case, that

                                       -8-



the resulting corporation or each such Wholly Owned Subsidiary assumes the
Obligations under the Loan Documents; or (z) a merger or consolidation in
which the holders of the Company's Voting Shares immediately prior to such
event continue to hold more than 50% of the Voting Shares outstanding
immediately after such event).

         "GAAP" shall mean generally accepted accounting principles applied
on a basis consistent with those that, in accordance with the last sentence
of Section 1.2(a) hereof, are to be used in making the calculations for
purposes of determining compliance with this Agreement.

         "GELTEX ACQUISITION" shall mean the transactions contemplated by the
GelTex Acquisition Documents.

         "GELTEX ACQUISITION DOCUMENTS" shall mean, individually and
collectively (i) Agreement and Plan of Merger by and among the Company, Titan
Acquisition Corp. and GelTex Pharmaceuticals, Inc. dated as of September 11,
2000, (ii) Agreement of Joinder executed and delivered by Titan Acquisition
Corp. on September 12, 2000, (iii) Amendment No. 1 to Agreement and Plan of
Merger dated October 19, 2000, among the Company, Titan Acquisition Corp. and
GelTex Pharmaceuticals, Inc., and (iv) Consent dated as of October 30, 2000
by the Company and Titan Acquisition Corp., together with all other
agreements of transfer as are referred to therein and all side letters with
respect thereto, and all agreements, documents and instruments executed
and/or delivered in connection therewith, as all of the foregoing now exist
or may hereafter be amended, modified, supplemented, extended, renewed,
restated, or replaced.

         "GUARANTEE" shall mean a guarantee, an endorsement, a contingent
agreement to purchase or to furnish funds for the payment or maintenance of,
or otherwise to be or become contingently liable under or with respect to,
the Indebtedness, other obligations, net worth, working capital or earnings
of any Person, or a guarantee of the payment of dividends or other
distributions upon the stock or equity interests of any Person, or an
agreement to purchase, sell or lease (as lessee or lessor) Property,
products, materials, supplies or services primarily for the purpose of
enabling a debtor to make payment of such debtor's obligations or an
agreement to assure a creditor against loss, and including, without
limitation, causing a bank or other financial institution to issue a letter
of credit or other similar instrument for the benefit of another Person, but
excluding endorsements for collection or deposit in the ordinary course of
business. The terms "Guarantee" and "Guaranteed" used as a verb shall have a
correlative meaning.

         "GUARANTEED OBLIGATIONS" shall have the meaning assigned to such
term in Section 6.1 hereof.

         "HAZARDOUS MATERIAL" shall mean, collectively, (a) any petroleum or
petroleum products, explosives, radioactive materials, asbestos, urea
formaldehyde foam insulation, and transformers or other equipment that
contain polychlorinated biphenyls ("PCB's") in concentrations that are
regulated under the Toxic Substances Control Act, as amended, or any other
Environmental Law, (b) any chemicals or other materials or substances that
are now or hereafter become defined as or included in the definition of
"hazardous substances", "hazardous wastes", "hazardous materials", "extremely
hazardous wastes", "restricted hazardous wastes", "toxic

                                       -9-



substances", "toxic pollutants", "contaminants", "pollutants" or words of
similar import under any Environmental Law and (c) any other chemical or
other material or substance, exposure to which is now or hereafter
prohibited, limited or regulated under any Environmental Law.

         "INITIAL ACQUISITION" shall mean the first to occur of the Biomatrix
Acquisition or the GelTex Acquisition.

         "INITIAL ACQUISITION DOCUMENTS" shall mean: (i) the Biomatrix
Acquisition Documents, if the Biomatrix Acquisition is the Initial
Acquisition; or (ii) the GelTex Acquisition Documents, if the GelTex
Acquisition is the Initial Acquisition.

         "INDEBTEDNESS" shall mean, for the Company and its Consolidated
Subsidiaries: (a) obligations created, issued or incurred by such Person for
borrowed money (whether by loan, the issuance and sale of debt securities or
the sale of Property to another Person subject to an understanding or
agreement, contingent or otherwise, to repurchase such Property from such
Person); (b) obligations of such Person to pay the deferred purchase or
acquisition price of Property or services, other than trade accounts payable
(other than for borrowed money) arising, and accrued expenses incurred, in
the ordinary course of business so long as such trade accounts payable are
payable within 120 days of the date the respective goods or services are
delivered or rendered; (c) Indebtedness of others secured by a Lien on the
Property of such Person, whether or not the respective Indebtedness so
secured has been assumed by such Person; (d) obligations of such Person,
contingent or otherwise, in respect of letters of credit, bankers'
acceptances or similar instruments issued or accepted by banks and other
financial institutions for account of such person; (e) Capital Lease
Obligations of such Person; (f) Synthetic Lease Obligations of such Person;
and (g) Guarantees by such Person of Indebtedness of others.

         "INTANGIBLE ASSETS" shall mean intangible assets, as determined in
accordance with GAAP, including, without limitation, all deferred assets,
patents, copyrights, trademarks, non-compete agreements and similar
intangibles, goodwill, unamortized debt discount and expenses, and all
investments other than Marketable Investments.

         "INTELLECTUAL PROPERTY" shall mean "Intellectual Property," as
defined in Section 101(60) of the Bankruptcy Code, now or hereafter owned by
Company or any of its Subsidiaries, together with all of the following
property now or hereafter owned by Company or any of its Subsidiaries: all
domestic and foreign patents and patent applications; inventions, discoveries
and improvements, whether or not patentable; trademarks, trademark
applications and registrations; service marks, service mark applications and
registrations; copyrights, copyright applications and registrations; all
licenses therefor; trade secrets and all other proprietary information.

         "INTEREST" shall mean, for any period, the sum, for the Company and
its Consolidated Subsidiaries, of the following: (a) all interest in respect
of Indebtedness (including, without limitation, the interest component of any
payments in respect of Capital Lease Obligations) accrued or capitalized
during such period (whether or not actually paid during such period); and (b)
all other amounts that would be accrued or capitalized during such period as
"interest expense" in accordance with GAAP.

                                       -10-



         "INTEREST PERIOD" shall mean: with respect to any LIBOR Loan, each
period commencing on the date such LIBOR Loan is made or Converted from a
Loan of another Type or the day after the last day of the next preceding
Interest Period for such Loan and ending on the numerically corresponding day
in the first, second, third or sixth calendar month thereafter, as the
Company may select as provided in Section 4.5 hereof, except that each
Interest Period that commences on the last Business Day of a calendar month
(or on any day for which there is no numerically corresponding day in the
appropriate subsequent calendar month) shall end on the last Business Day of
the appropriate subsequent calendar month; PROVIDED, THAT, notwithstanding
the foregoing:

                (i) (a) if any Interest Period for any 364-Day Facility
       Revolving Credit Loan would otherwise end after the 364-Day Facility
       Revolving Credit Commitment Termination Date, such Interest Period
       shall not be available hereunder; and (b) if any Interest Period for
       any Three-Year Facility Revolving Credit Loan would otherwise end after
       the Three-Year Facility Revolving Credit Commitment Termination Date,
       such Interest Period shall not be available hereunder;

                (ii) each Interest Period that would otherwise end on a day
       that is not a Business Day shall end on the next succeeding Business
       Day (or, if such next succeeding Business Day falls in the next
       succeeding calendar month, on the next preceding Business Day); and

                (iii) notwithstanding clauses (i) and (ii) above, no Interest
       Period for any LIBOR Loan shall have a duration of less than one month
       and, if the Interest Period for any LIBOR Loan would otherwise be a
       shorter period, such Loan shall not be available as a LIBOR Loan
       hereunder for such period.

         "INVESTMENT" shall mean, for any Person: (a) the acquisition
(whether for cash, Property, services or securities or otherwise) of capital
stock, bonds, notes, debentures, partnership or other ownership interests or
other securities of any other Person or any agreement to make any such
acquisition (including, without limitation, any "short sale" or any sale of
any securities at a time when such securities are not owned by the Person
entering into such sale); (b) the making of any deposit with, or advance,
loan or other extension of credit to, any other Person (including the
purchase of Property from another Person subject to an understanding or
agreement, contingent or otherwise, to resell such Property to such Person),
but excluding any such advance, loan or extension of credit arising in
connection with the sale of inventory or supplies by such Person in the
ordinary course of business so long as such advance, loan or extension of
credit is made on terms (including as to maturity) consistent with those
terms offered by the Company on the date hereof; and (c) the entering into of
any Guarantee of, or other contingent obligation with respect to,
Indebtedness or other liability of any other Person and (without duplication)
any amount committed to be advanced, lent or extended to such Person.

         "LEVEL I PERIOD" shall mean any period, other than a Level II
Period, Level III Period, or Level IV Period.

         "LEVEL II PERIOD" shall mean any period (a) from and including the
Business Day immediately following the Business Day on which a senior
financial officer of the Company shall have delivered to the Administrative
Agent a Compliance Certificate, together with the

                                       -11-



related financial statements referred to in Section 9.1 hereof, demonstrating
in reasonable detail that the Consolidated Debt Coverage Ratio, as of the
last day of the fiscal quarter of the Company most recently ended, is greater
than or equal to 1.0 to 1.0, but less than 1.5 to 1.0, to but excluding the
next succeeding Reporting Date and (b) during which no Event of Default shall
have occurred and be continuing.

         "LEVEL III PERIOD" shall mean any period, other than a Level IV
Period, (a) from and including the Business Day immediately following the
Business Day on which a senior financial officer of the Company shall have
delivered to the Administrative Agent a Compliance Certificate, together with
the related financial statements referred to in Section 9.1 hereof,
demonstrating in reasonable detail that the Consolidated Debt Coverage Ratio,
as of the last day of the fiscal quarter of the Company most recently ended,
is greater than or equal to 1.5 to 1.0, to but excluding the next succeeding
Reporting Date and (b) during which no Event of Default shall have occurred
and be continuing.

         "LEVEL IV PERIOD" shall mean any period (a) from and including the
Business Day immediately following the Business Day on which a senior
financial officer of the Company shall have delivered to the Administrative
Agent a Compliance Certificate, together with the related financial
statements referred to in Section 9.1 hereof, demonstrating in reasonable
detail that the Consolidated Debt Coverage Ratio, as of the last day of the
fiscal quarter of the Company most recently ended, is greater than or equal
to 1.5 to 1.0, AND for which the Administrative Agent has received written
confirmation from the respective debt rating company that the Senior
Unsecured Debt Rating of the Company, as of the last day of the fiscal
quarter of the Company most recently ended, is at least A- with regard to
Standard & Poor's or A3 with regard to Moody's Investors Service, to but
excluding the next succeeding Reporting Date and (b) during which no Event of
Default shall have occurred and be continuing.

         "LIBO RATE" shall mean, with respect to any LIBOR Loan for any
Interest Period therefor, the simple average (rounded upwards, if necessary,
to the nearest 1/32 of 1%), as determined by the Administrative Agent, of the
rates per annum which appear on the Telerate page 3750 as of 11:00 a.m.
London time on the day that is two Business Days prior to the first day of
such Interest Period (provided, that if the rate described above does not
appear on the Telerate System on any applicable interest determination date,
then at the rates per annum quoted to the Administrative Agent at
approximately 11:00 a.m. London time (or as soon thereafter as practicable)
on the date two Business Days prior to the first day of such Interest Period
for the offering by leading banks in the London interbank market) of Dollar
deposits having a term comparable to such Interest Period and in an amount
comparable to the principal amount of the LIBOR Loan to be made by the
Lenders for such Interest Period.

         "LIBOR LOANS" shall mean loans bearing interest at the rate
determined under Section 3.2(b).

         "LIEN" shall mean, with respect to any Property, any mortgage, lien,
pledge, charge, security interest or encumbrance of any kind in respect of
such property. For purposes of this Agreement and the other Loan Documents, a
Person shall be deemed to own subject to a Lien any Property that it has
acquired or holds subject to the interest of a vendor or lessor under any
conditional sale agreement, capital lease or other title retention agreement
(other than an operating lease) relating to such Property.

                                       -12-



         "LOAN DOCUMENTS" shall mean this Agreement, the Notes, the Pledge
Agreement and all other agreements, instruments and documents entered into
pursuant hereto or thereto as such may be amended, modified or changed from
time to time.

         "LOANS" shall mean Prime Rate Loans and LIBOR Loans.

         "MARGIN STOCK" shall mean "margin stock" within the meaning of
Regulations U and X.

         "MARKETABLE INVESTMENTS" shall mean any interest-bearing debt
obligations owned by Company and its Wholly-Owned Subsidiaries (excluding
directors' qualifying shares and items included as Cash Equivalents) which
meet the definition of marketable securities under GAAP. Such amounts shall
exclude common or preferred stock. Such securities shall include obligations
issued by the U.S. Treasury and other agencies of the U.S. government,
corporate bonds, bank notes, mortgage and asset backed securities, finance
company securities and auction rate preferred stocks. Such securities shall
be rated investment grade (BBB or better for bonds or similar securities,
A1/P1 for commercial paper and notes) and shall otherwise be reasonably
liquid investments.

         "MATERIAL ADVERSE EFFECT" shall mean a material adverse effect on
(a) the business, operations or financial condition or material Property of
the Company and its Subsidiaries, taken as a whole, (b) the validity or
enforceability of any of the Loan Documents or the rights and remedies of the
Lenders and the Agents thereunder or (c) the ability of the Obligors to
perform their obligations hereunder including the timely payment of the
principal of or interest on the Loans or other amounts in connection
therewith.

         "MATERIAL SUBSIDIARY" shall mean any Subsidiary of the Company, the
total assets of which equal or exceed five percent (5%) of the Consolidated
total assets of the Company and its Subsidiaries taken as a whole, and each
as reported in the books and records of the Company and its Subsidiaries and
as calculated in accordance with GAAP, and, for the purposes of Sections 6
and 9.13 hereof means such a Subsidiary of the Company that is organized
under the laws of the United States, provided that Genzyme Securities
Corporation shall not be deemed to be a Material Subsidiary for purposes of
Sections 6 and 9.13 hereof. Effective upon and as of the Initial Acquisition,
the entity acquired pursuant to (or, as applicable, the surviving entity of
any merger effected by) the Initial Acquisition Documents shall be deemed to
be a Material Subsidiary. Effective upon and as of the Second Acquisition,
the entity acquired pursuant to (or, as applicable, the surviving entity of
any merger effected by) the Second Acquisition Documents shall be deemed to
be a Material Subsidiary.

         "MULTIEMPLOYER PLAN" shall mean a multiemployer plan defined as such
in Section 3(37) of ERISA to which contributions have been made by the
Company or any ERISA Affiliate and that is covered by Title IV of ERISA.

         "NOTES" shall mean the Revolving Credit Notes.

         "OBLIGATIONS" shall mean any and all of the Revolving Credit Loans,
including any principal, interest, charges, fees, costs and expenses
(including interest arising after the filing of any bankruptcy petition and
notwithstanding any law to the contrary) and all other obligations

                                       -13-



liabilities and indebtedness of the Company or any Obligor of any kind,
nature or description arising under this Agreement, the Notes or any other
Loan Documents.

         "PBGC" shall mean the Pension Benefit Guaranty Corporation or any
entity succeeding to any or all of its functions under ERISA.

         "PERSON" shall mean any individual, corporation, company, voluntary
association, partnership, joint venture, trust, unincorporated organization
or government (or any agency, instrumentality or political subdivision
thereof) and shall include any syndicate or group which would be deemed to be
a "person" under Section 13(d)(3) of the Exchange Act.

         "PLAN" shall mean an employee benefit or other plan established or
maintained by the Company or any ERISA Affiliate and that is covered by Title
IV of ERISA, other than a Multiemployer Plan.

         "PLEDGE AGREEMENT" shall mean the Pledge Agreement provided under
Section 7.1(f) as the same such shall be modified, amended and supplemented
from time to time.

         "POST-DEFAULT RATE" shall mean a rate per annum equal to 4% PLUS the
interest rate for a Loan as provided in one of the lettered paragraphs of
Section 3.2 for a Level I Period.

         "PRIME RATE" shall mean for any day the rate equal to the higher
from time to time of (A) the rate of interest announced by the Administrative
Agent at the Principal Office from time to time as its prime rate; and (B) a
rate equal to 1/2 of 1% per annum above the weighted average of the rates on
overnight federal funds transactions with members of the Federal Reserve
System arranged by federal funds brokers, as determined on any day by the
Administrative Agent.

         "PRIME RATE LOANS" shall mean loans bearing interest at the rate
determined under Section 3.2(a).

         "PRINCIPAL OFFICE" shall mean the principal office of Fleet, located
on the date hereof at 100 Federal Street, Boston, Massachusetts 02110, or
such other principal office of the Administrative Agent, after written notice
by the Administrative Agent.

         "PRIOR CREDIT AGREEMENT" shall mean that certain Credit Agreement
dated as of November 12, 1999, among the Company, the Subsidiary Guarantors
thereto, the Lenders thereto, Fleet, as Administrative Agent, ABN AMRO Bank
N.V., as Syndication Agent, and Mellon Bank, N.A., as Documentation Agent.

         "PRIOR CREDIT AGREEMENT PARTIES" shall mean the parties to the Prior
Credit Agreement.

         "PROPERTY" shall mean any right or interest in or to property of any
kind whatsoever, whether real, personal or mixed and whether tangible or
intangible.

         "PURCHASED BIOMATRIX STOCK" shall mean all of the issued and
outstanding shares of common stock of Biomatrix, Inc.

                                       -14-



         "PURCHASED GELTEX STOCK" shall mean all of the issued and
outstanding shares of common stock of GelTex Pharmaceuticals, Inc.

         "PURCHASED INITIAL STOCK" shall mean: (i) the Purchased Biomatrix
Stock, if the Biomatrix Acquisition is the Initial Acquisition; or (ii) the
Purchased GelTex Stock, if the GelTex Acquisition is the Initial Acquisition.

         "PURCHASE MONEY INDEBTEDNESS" shall mean Indebtedness incurred by a
Person to purchase machinery, equipment and other fixed assets, but only (i)
if the amount of such Indebtedness is not greater than 100% of the invoice
amount of such purchased machinery, equipment and other fixed assets, and
(ii) such Indebtedness, if secured, is secured by a security interest in only
the purchased machinery, equipment and other fixed assets and such Person has
not granted a lien or security interest to secure such Indebtedness on any
other property of such Person other than such purchased fixed assets; and
(iii) such purchased fixed assets do not constitute all or substantially all
of the fixed assets of any Person or any division of any Person.

         "QUARTERLY DATES" shall mean the last Business Day of March, June,
September and December of each year, the first of which shall be the first
such day after the date hereof.

         "REGULATIONS A, D, U AND X" shall mean, respectively, Regulations A,
D, U and X of the Board of Governors of the Federal Reserve System (or any
successor), as the same may be modified and supplemented and in effect from
time to time.

         "REGULATORY CHANGE" shall mean, with respect to any Lender, any
change after the date hereof in Federal, state or foreign law or regulations
(including, without limitation, Regulation D) or the adoption or making after
such date of any interpretation, directive or request applying to a class of
banks including such Lender of or under any Federal, state or foreign law or
regulations (whether or not having the force of law and whether or not
failure to comply therewith would be unlawful) by any court or governmental
or monetary authority charged with the interpretation or administration
thereof.

         "RELEASE" shall mean any release, spill, emission, leaking, pumping,
injection, deposit, disposal, discharge, dispersal, leaching or migration
into the indoor or outdoor environment, including, without limitation, the
movement of Hazardous Materials through ambient air, soil, surface water,
ground water, wetlands, land or subsurface strata.

         "REPORTING DATE" shall mean the first to occur of (i) the Business
Day following the Business Day that the Administrative Agent receives a
Compliance Certificate of the Company providing the information required to
determine whether a period is a Level I Period, Level II Period, Level III
Period or Level IV Period and (ii) the first Business Day after the date on
which the quarterly or annual financial statement and Compliance Certificate
is required to be delivered to the Lenders pursuant to Section 9.1(a) or (b)
and (c).

         "REQUIRED LENDERS" shall mean Lenders having at least 51% of the
aggregate amount of the Commitments or, if the Commitments shall have
terminated, Lenders holding at least 51% of the aggregate unpaid principal
amount of the Loans.

                                       -15-



         "RESERVE REQUIREMENT" shall mean, for any Interest Period for a
LIBOR Loan, the average maximum rate at which reserves (including, without
limitation, any marginal, supplemental or emergency reserves) are required to
be maintained during such Interest Period under Regulation D by member banks
of the Federal Reserve System in New York City with deposits exceeding one
billion Dollars against "Eurocurrency liabilities" (as such term is used in
Regulation D). Without limiting the effect of the foregoing, the Reserve
Requirement shall include any other reserves required to be maintained by
such member banks by reason of any Regulatory Change with respect to (i) any
category of liabilities that includes deposits by reference to which the
LIBOR Loan is to be determined or (ii) any category of extensions of credit
or other assets that includes LIBOR Loans.

         "REVOLVING CREDIT COMMITMENT" shall mean, for each Revolving Credit
Lender, the sum of such Lender's Three-Year Facility Revolving Credit
Commitment and 364-Day Facility Revolving Credit Commitment.

         "REVOLVING CREDIT COMMITMENT PERCENTAGE" shall mean, with respect to
any Revolving Credit Lender, the ratio of (a) the amount of the Revolving
Credit Commitment of such Lender to (b) the aggregate amount of the Revolving
Credit Commitments of all of the Lenders.

         "REVOLVING CREDIT LENDERS" shall mean the Lenders from time to time
holding Revolving Credit Loans and/or Revolving Credit Commitments.

         "REVOLVING CREDIT LOANS" shall mean the loans provided for in
Section 2.1 hereof, which may be Prime Rate Loans and/or LIBOR Loans, and
which may be Three-Year Facility Revolving Credit Loans or 364-Day Facility
Revolving Credit Loans.

         "REVOLVING CREDIT NOTES" shall mean the promissory notes provided
for by Section 2.7(a) hereof and all promissory notes delivered in
substitution or exchange for any thereof, in each case as the same shall be
modified and supplemented and in effect from time to time.

         "SECOND ACQUISITION" shall mean: (ii) the GelTex Acquisition, if the
Biomatrix Acquisition is the Initial Acquisition; or (ii) the Biomatrix
Acquisition, if the GelTex Acquisition is the Initial Acquisition.

         "SECOND ACQUISITION CONDITIONS PRECEDENT" shall mean the occurrence
of all of the following, but only if each and all of them have occurred on or
prior to the date that is ninety (90) days after the Closing Date:

       (i)      The Company shall have made available to the Lenders signed
                copies of the Second Acquisition Documents;

       (ii)     The Administrative Agent shall have received the Company's
                certificate that the Second Acquisition Documents posted to
                the www.Intralinks.com web-site on or prior to December 13,
                2000, have not been amended, and that the transactions
                contemplated under the terms thereof have been consummated
                prior to or will be consummated contemporaneously with the
                requested Loans;

                                       -16-



       (iii)    The Company shall have made, in writing, all representations
                and warranties with respect to the Second Acquisition and the
                Second Acquisition Documents as the Company has made with
                respect to the First Acquisition pursuant to Section 8.19
                hereof; and

       (iv)     The Company shall have complied with Section 9.13 hereof with
                respect to the entity that has become a Material Subsidiary by
                virtue of the Second Acquisition.


         "SECOND ACQUISITION DOCUMENTS" shall mean: (ii) the Biomatrix
Acquisition Documents, if the Biomatrix Acquisition is the Second
Acquisition; or (ii) the GelTex Acquisition Documents, if the GelTex
Acquisition is the Second Acquisition.

         "SENIOR UNSECURED DEBT RATING" shall mean, for any date, the senior
unsecured debt rating, as rated by Standard & Poor's or Moody's Investor
Service as of such date.

         "SUBORDINATED DEBT" means (1) the Company's Convertible Debentures,
issued August 29, 1997, in the original aggregate principal amount of $20
million, (2) the Company's Convertible Notes, issued May 19, 1998, in the
original aggregate principal amount of $250 million, (3) unsecured
Indebtedness of the Company or a Subsidiary of the Company which, by its
terms, is explicitly subordinated to the prior payment in full of the
Obligations to at least the following extent: (a) no payments of principal of
(or premium, if any) or interest on (or otherwise due in respect of) such
Indebtedness may be permitted for so long as any Default or Event of Default
in the payment of principal (or premium, if any) or interest on the Loans
exists; (b) in the event that any other Default or Event of Default exists,
upon notice by the Required Lenders, the Administrative Agent shall have the
right to give notice to the Company and the holders of such Indebtedness (or
agents therefor) of a payment blockage, and thereafter no payments of
principal of (or premium, if any) or interest on (or otherwise due in respect
of) such Indebtedness may be made for a period of 179 days from the date of
such notice unless, prior to such time, such Default or Event of Default is
cured or waived; PROVIDED, HOWEVER, that only one such notice of a payment
blockage shall be effective during any 365 consecutive day period and
PROVIDED, FURTHER, that no such other Default or Event of Default that
existed upon first delivery of such a notice shall be the basis for a
subsequent notice of payment blockage unless such Default or Event of Default
shall have been cured or waived for a period of 180 consecutive days; (c)
such Indebtedness may not (i) provide for payments of principal of such
Indebtedness at the stated maturity thereof or by way of a sinking fund
applicable thereto or by way of any mandatory redemption, defeasance,
retirement or repurchase thereof by the Company or any Subsidiary (including
any redemption, retirement or repurchase which is contingent upon events or
circumstances but not including any exchange, conversion or payment with
equity or other Subordinated Debt), in each case prior to the Three-Year
Facility Revolving Credit Commitment Termination Date or (ii) permit
redemption or other retirement (including pursuant to an offer to purchase
made by the Company or any Subsidiary) of such other Indebtedness at the
option of the holder thereof prior to the Three-Year Facility Revolving
Credit Commitment Termination Date other than by conversion to Capital Stock
or other equity of the Company or other Subordinated Debt; PROVIDED, HOWEVER,
in the case of either (i) or (ii), such Indebtedness may provide for payment
prior to the stated maturity of such Indebtedness if any event which causes,
or (with the giving of any notice or the lapse of time or both) permits the
holder or holders of such Indebtedness (or a trustee or agent on behalf of
such holder or

                                       -17-



holders) to cause such Indebtedness to become due, or to be prepaid (whether by
redemption, purchase, offer to purchase or otherwise), prior to its stated
maturity would also cause a Default or an Event of Default (subject, however,
to the limitations of clauses (a), (b), (d) and (e) hereof); (d) the terms of
such Indebtedness shall provide, to the extent not prohibited in the Trust
Indenture Act of 1939, as amended, that no action to enforce the payment
thereof or to exercise any remedy with respect thereto shall occur unless the
holders of such Indebtedness (or agents therefor) give the Administrative Agent
notice of such default and thereafter no such enforcement action or exercise of
remedies shall occur until 180 days shall have elapsed from the date of such
notice without the cure or waiver of such default, provided that such
standstill period shall continue for as long as a Default or an Event of
Default under clause (a) above exists; provided, further, however, that the
restrictions described in this clause (d) shall not apply if the event which
gives rise to the right to enforce such payment or exercise such remedy
triggers a Default or an Event of Default (subject, however, to the limitations
of clauses (a), (b), (c), and (e); and (e) such Indebtedness shall further
provide that, upon any bankruptcy, insolvency, liquidation or similar case or
proceeding relative to the Company or any of its Subsidiaries, or upon the
realization of any amounts by the holders of the Indebtedness (or the agents
therefor) resulting from an action under clause (d) above, the Obligations
shall first be paid in full to the Administrative Agent or such payment shall
have been provided for to the satisfaction of the Required Lenders before any
payment or distribution is made to or retained by the holders of the
Indebtedness (or the agents therefor), (4) any other Indebtedness of the
Company or its Subsidiaries, incurred after the date hereof, containing
subordination terms, which are specifically consented to in writing by the
Required Lenders and (5) any refinancing of Subordinated Debt incurred pursuant
to subsections (1), (2), (3) or (4), in which (x) the principal amount of
Subordinated Debt resulting from such refinancing does not exceed the sum of
(i) the principal amount of the Subordinated Debt so refinanced plus (ii)
customary fees and expenses incurred in connection with such refinancing and
(y) the Indebtedness resulting from such refinancing satisfies the criteria for
Subordinated Debt hereunder.

         "SUBSIDIARY" shall mean, with respect to any Person, any
corporation, partnership or other entity of which at least a majority of the
securities or other ownership interests having by the terms thereof ordinary
voting power to elect a majority of the board of directors or other persons
performing similar functions of such corporation, partnership or other entity
(irrespective of whether or not at the time securities or other ownership
interests of any other class or classes of such corporation, partnership or
other entity shall have or might have voting power by reason of the happening
of any contingency), or of which at least a majority of the limited
partnership interests or other similar ownership interests issued by any
limited partnership or other similar entity, is at the time directly or
indirectly owned or controlled by such Person or one or more Subsidiaries of
such Person or by such Person and one or more Subsidiaries of such Person.

         "SYNTHETIC LEASE OBLIGATIONS" shall mean, for any Person, all
obligations of such Person to pay rent or other amounts under or in
connection with any so-called "synthetic lease" (i.e., a lease (or other
agreement conveying the right to use) of property that constitutes a lease in
accordance with GAAP but that does not constitute a lease for Federal income
tax purposes), including, without limitation, obligations under: (i) the
Agency Agreement, dated as of October 21, 1998 (the "Agency Agreement")
between GelTex Pharmaceuticals, Inc. and First Security Bank, N.A., not in
its individual capacity except as expressly set forth in the Agency

                                       -18-



Agreement, but solely as Trustee under the Owner Trust Agreement dated as of
October 21, 1998 (the "Owner Trust Agreement") between Fleet Real Estate,
Inc. and First Security Bank, N.A., not in its individual capacity except as
expressly set forth in the Agency Agreement, but solely as Trustee under the
Owner Trust Agreement; and (ii) a Lease Agreement, dated as of October 21,
1998 (the "Lease Agreement"), between GelTex Pharmaceuticals, Inc. and First
Security Bank, N.A., not in its individual capacity except as expressly set
forth in the Lease Agreement, but solely as Trustee under the Owner Trust
Agreement.

         "TAXES" shall mean any present or future tax (including, without
limitation, any income, documentary, sales, stamp, registration, property or
excise tax), assessment or other charge, levy, impost, fee, compulsory loan,
charge or withholding.

         "364-DAY FACILITY REVOLVING CREDIT COMMITMENT" shall mean, for each
Revolving Credit Lender, the obligation of such Lender to make 364-Day
Facility Revolving Credit Loans in an aggregate principal amount at any one
time outstanding up to but not exceeding (a) in the case of any such Lender
originally party hereto, the sum of (i) the amount set opposite the name of
such Lender on the signature pages hereto under the appropriate caption: (a)
"Initial 364-Day Facility Revolving Credit Availability", prior to the
consummation of the Second Acquisition and satisfaction of the Second
Acquisition Conditions Precedent, or (b) "Post-Second Acquisition 364-Day
Facility Revolving Credit Commitment", upon and following the consummation of
the Second Acquisition and satisfaction of the Second Acquisition Conditions
Precedent plus (ii) the aggregate amount of 364-Day Facility Revolving Credit
Commitments acquired by such Lender from other Lenders pursuant to Section
12.7(b) hereof minus (iii) the aggregate amount of 364-Day Facility Revolving
Credit Commitments transferred by such Lender to one or more other Lenders
pursuant to Section 12.7(b) hereof and (b) in the case of any such Lender
that was not originally party hereto, (i) the aggregate amount of 364-Day
Facility Revolving Credit Commitments acquired by such Lender from other
Lenders pursuant to Section 12.7(b) hereof minus (ii) the aggregate amount of
364 Day Facility Revolving Credit Commitments transferred by such Lender to
one or more other Lenders pursuant to Section 12.7(b) hereof, in each case,
as such obligation may be reduced from time to time pursuant to Section 2.3
hereof.

         "364-DAY FACILITY REVOLVING CREDIT COMMITMENT TERMINATION DATE"
shall be December 12, 2001.

         "364-DAY FACILITY REVOLVING CREDIT LOANS" shall have the meaning
given in Section 2.1(b) hereof.

         "THREE-YEAR FACILITY REVOLVING CREDIT COMMITMENT" shall mean, for
each Revolving Credit Lender, the obligation of such Lender to make
Three-Year Facility Revolving Credit Loans in an aggregate principal amount
at any one time outstanding up to but not exceeding (a) in the case of any
such Lender originally party hereto, the sum of (i) the amount set opposite
the name of such Lender on the signature pages hereto under the appropriate
caption: (a) "Initial Three-Year Facility Revolving Credit Availability",
prior to the consummation of the Second Acquisition and satisfaction of the
Second Acquisition Conditions Precedent, or (b) "Post-Second Acquisition
Three-Year Facility Revolving Credit Commitment", upon and following the
consummation of the Second Acquisition and satisfaction of the Second
Acquisition Conditions Precedent, plus (ii) the aggregate amount of
Three-Year Facility Revolving Credit

                                       -19-



Commitments acquired by such Lender from other Lenders pursuant to Section
12.7(b) hereof minus (iii) the aggregate amount of Three-Year Facility
Revolving Credit Commitments transferred by such Lender to one or more other
Lenders pursuant to Section 12.7(b) hereof and (b) in the case of any such
Lender that was not originally party hereto, (i) the aggregate amount of
Three-Year Facility Revolving Credit Commitments acquired by such Lender from
other Lenders pursuant to Section 12.7(b) hereof minus (ii) the aggregate
amount of Three-Year Facility Revolving Credit Commitments transferred by
such Lender to one or more other Lenders pursuant to Section 12.7(b) hereof,
in each case, as such obligation may be reduced from time to time pursuant to
Section 2.3 hereof.

         "THREE-YEAR FACILITY REVOLVING CREDIT COMMITMENT TERMINATION DATE"
shall be December 14, 2003.

         "THREE-YEAR FACILITY REVOLVING CREDIT LOANS" shall have the meaning
given in Section 2.1(a) hereof.

         "TYPE" shall have the meaning given such term in Section 1.3 hereof.

         "UNRESTRICTED CASH" shall mean cash and Cash Equivalents of the
Company and its Wholly Owned Subsidiaries that are readily available to
Company and not subject to any limitation or restriction on their use by the
Company.

         "U.S. PERSON" shall mean a citizen or resident of the United States
of America, a corporation, partnership or other entity created or organized
in or under any laws of the United States of America or any State thereof, or
any estate or trust that is subject to Federal income taxation regardless of
the source of its income.

         "VOTING SHARES" shall mean all outstanding shares of any class or
series (however designated) of Capital Stock entitled to vote generally in
the election of members of the Board of Directors of the Company.

         "WHOLLY OWNED SUBSIDIARY" shall mean, with respect to any Person,
any corporation, partnership or other entity to which all of the equity
securities or other ownership interests (other than, in the case of a
corporation, directors' qualifying shares or, in the case of a limited
partnership, not more than 1% of the aggregate partnership interests issued
by such limited partnership) are directly or indirectly owned or controlled
by such Person or one or more Wholly Owned Subsidiaries of such Person or by
such Person and one or more Wholly Owned Subsidiaries of such Person.

       1.2.     ACCOUNTING TERMS AND DETERMINATIONS.

                (a) Except as otherwise expressly provided herein, all
       accounting terms used herein shall be interpreted, and all financial
       statements and certificates and reports as to financial matters
       required to be delivered to the Lenders hereunder shall (unless
       otherwise disclosed to the Lenders in writing at the time of delivery
       thereof in the manner described in subsection (b) below) be prepared,
       in accordance with GAAP applied on a basis consistent with those used
       in the preparation of the latest annual or quarterly financial
       statements furnished to the Lenders hereunder (which, prior to the

                                       -20-



       delivery of the first annual or quarterly financial statements under
       Section 9.1 hereof, shall mean the audited financial statements as at
       December 31, 1999 referred to in Section 8.2 hereof).

                (b) To enable the ready and consistent determination of
       compliance with the covenants set forth in Section 9 hereof, the
       Company will not change its fiscal year.

         1.3. TYPES OF LOANS/FACILITIES. Loans hereunder are distinguished by
"Type" and "Facility". The "Type" of a Loan refers to whether such Loan is a
Prime Rate Loan or a LIBOR Loan. The "Facility" refers to whether such Loan
is made under the Three-Year Facility or the 364-Day Facility.

Section 2.  COMMITMENTS, LOANS, NOTES AND PREPAYMENTS.

       2.1.     REVOLVING CREDIT LOANS.

                (a) THREE-YEAR FACILITY. Each Lender severally agrees, on the
       terms and conditions of this Agreement, to make loans to the Company in
       Dollars during the period from and including the Closing Date to but
       not including the Three-Year Facility Revolving Credit Commitment
       Termination Date in an aggregate principal amount at any one time
       outstanding up to but not exceeding the amount of the Three-Year
       Facility Revolving Credit Commitment of such Lender as in effect from
       time to time (such Loans being herein called "THREE-YEAR FACILITY
       REVOLVING CREDIT LOANS"); PROVIDED THAT (i) the Three-Year Facility
       Revolving Credit Loans outstanding shall not exceed $245,000,000 prior
       to the consummation of the Second Acquisition and satisfaction of the
       Second Acquisition Conditions Precedent; and (ii) in no event shall the
       Three-Year Facility Revolving Credit Loans at any time outstanding
       exceed the aggregate amount of the Three-Year Facility Revolving Credit
       Commitments as in effect from time to time. Subject to the terms and
       conditions of this Agreement, during such period the Company may
       borrow, repay and reborrow the amount of the Three-Year Facility
       Revolving Credit Commitments by means of Prime Rate Loans and LIBOR
       Loans and may Convert Three-Year Facility Revolving Credit Loans of one
       Type into Three-Year Facility Revolving Credit Loans of another Type
       (as provided in Section 2.8 hereof) or Continue Three-Year Facility
       Revolving Credit Loans of one Type as Three-Year Facility Revolving
       Credit Loans of the same Type (as provided in Section 2.8 hereof).

                (b) 364-DAY FACILITY. Each Lender severally agrees, on the
       terms and conditions of this Agreement, to make loans to the Company in
       Dollars during the period from and including the Closing Date to but
       not including the 364-Day Facility Revolving Credit Commitment
       Termination Date in an aggregate principal amount at any one time
       outstanding up to but not exceeding the amount of the 364-Day Facility
       Revolving Credit Commitment of such Lender as in effect from time to
       time (such Loans being herein called "364-DAY FACILITY REVOLVING CREDIT
       LOANS"); PROVIDED THAT (i) the 364-Day Facility Revolving Credit Loans
       outstanding shall not exceed $105,000,000 prior to the consummation of
       the Second Acquisition and satisfaction of the Second Acquisition
       Conditions Precedent; and (ii) in no event shall the 364-Day Facility
       Revolving Credit Loans at any time outstanding exceed the aggregate
       amount of the

                                       -21-



       364-Day Facility Revolving Credit Commitments as in
       effect from time to time. Subject to the terms and conditions of this
       Agreement, during such period the Company may borrow, repay and
       reborrow the amount of the 364-Day Facility Revolving Credit
       Commitments by means of Prime Rate Loans and LIBOR Loans and may
       Convert 364-Day Facility Revolving Credit Loans of one Type into
       364-Day Facility Revolving Credit Loans of another Type (as provided in
       Section 2.8 hereof).

                (c) INTEREST PERIODS. No more than five separate Interest
       Periods in respect of LIBOR Loans may be outstanding at any one time.

                (d) REVOLVING CREDIT COMMITMENTS. In no event shall the
       Revolving Credit Loans at any time outstanding exceed the aggregate
       amount of the Revolving Credit Commitments as in effect from time to
       time. Prior to the consummation of the Second Acquisition and
       compliance with the Second Acquisition Conditions Precedent, the
       aggregate Revolving Credit Loans outstanding shall not exceed
       $350,000,000.00.

         2.2. BORROWINGS OF REVOLVING CREDIT LOANS. The Company shall give
the Administrative Agent notice of each borrowing hereunder as provided in
Section 4.5 hereof, and the Administrative Agent shall promptly give each
Lender notice thereof. Not later than 1:00 p.m. Boston, Massachusetts time on
the date specified for each borrowing of Revolving Credit Loans hereunder,
each Lender shall make available the amount of the Loan or Loans to be made
by it on such date to the Administrative Agent, at account number 1510351
maintained by the Administrative Agent with Fleet at the Principal Office,
or, after written notice by the Administrative Agent to the Lenders, at such
other account maintained by the Administrative Agent, in immediately
available funds, for the account of the Company. The amount so received by
the Administrative Agent shall, subject to the terms and conditions of this
Agreement, be made available to the Company by depositing the same, in
immediately available funds, in an account of the Company maintained with
Fleet at the Principal Office designated for the Company, or at such other
account designated in writing by the Administrative Agent.

         2.3.     CHANGES OF COMMITMENTS.

                (a) (i) The aggregate amount of the 364-Day Facility Revolving
       Credit Commitments shall be automatically reduced to zero on the
       364-Day Facility Revolving Credit Commitment Termination Date; and (ii)
       the aggregate amount of the Three-Year Facility Revolving Credit
       Commitments shall be automatically reduced to zero on the Three-Year
       Facility Revolving Credit Commitment Termination Date.

                (b) The Company shall have the right at any time or from time
       to time to reduce the aggregate unused amount of the Three-Year
       Facility Revolving Credit Commitments and the 364-Day Facility
       Revolving Credit Commitments (for which purpose the Revolving Credit
       Commitments shall be deemed to be utilized by the amount of the
       Revolving Credit Loans); PROVIDED that (x) the Company shall give
       notice of each such termination or reduction as provided in Section 4.5
       hereof, which notice shall specify the amount of the total reduction,
       and the amount of the reduction for each Facility, and (y) each partial
       reduction to the aggregate Revolving Credit Commitments

                                       -22-



       shall be in an aggregate amount at least equal to $5,000,000 (or
       any integral multiple of $1,000,000 in excess thereof).

                (c) The Commitments once terminated or reduced may not be
       reinstated.

         2.4. COMMITMENT FEE. The Company shall pay to the Administrative
Agent for the account of each Lender a commitment fee on the daily average
unused amount of such Lender's Commitment (without regard to whether the
Borrower is permitted by the terms hereof to borrow the full amount of such
Commitment and provided that, for the purposes only of calculating the
commitment fee under this Section 2.4, each Lender's Commitment shall be
calculated as if the Post-Second Acquisition 364-Day Facility Revolving
Credit Commitments and the Post-Second Acquisition Three-Year Facility
Revolving Credit Commitments were in effect), for the period from and
including the date hereof to but not including the date such Commitment is
terminated or expires, at a rate per annum equal to the Applicable Commitment
Fee Rate. Accrued commitment fees shall be payable in arrears on each
Quarterly Date and on the date the respective Revolving Credit Commitments
are terminated or expire.

         2.5. LENDING OFFICES. The Loans of each Type made by each Lender
shall be made and maintained at such Lender's Applicable Lending Office for
Loans of such Type.

         2.6. SEVERAL OBLIGATIONS; REMEDIES INDEPENDENT. The failure of any
Lender to make any Loan to be made by it on the date specified therefor shall
not relieve any other Lender of its obligation to make its Loan on such date,
but neither any Lender nor any Agent shall be responsible for the failure of
any other Lender to make a Loan to be made by such other Lender, and (except
as otherwise provided in Section 4.6 hereof) no Lender shall have any
obligation to any Agent or any other Lender for the failure by such Lender to
make any Loan required to be made by such Lender. The amounts payable by the
Company at any time hereunder and under the Note to each Lender shall be a
separate and independent debt and each Lender shall be entitled to protect
and enforce its rights arising out of this Agreement and the Notes, and it
shall not be necessary for any other Lender or any Agent to consent to, or be
joined as an additional party in, any proceedings for such purposes.

         2.7.     NOTES.

                (a) (i) The Three-Year Facility Revolving Credit Loans made by
       each Lender shall be evidenced by a single promissory note of the
       Company substantially in the form of EXHIBIT A hereto, dated the date
       hereof, payable to such Lender in a principal amount equal to the
       amount of its Three-Year Facility Revolving Credit Commitment as
       originally in effect and otherwise duly completed; and (ii) the 364-Day
       Facility Revolving Credit Loans made by each Lender shall be evidenced
       by a single promissory note of the Company substantially in the form of
       EXHIBIT B hereto, dated the date hereof, payable to such Lender in a
       principal amount equal to the amount of its 364-Day Facility Revolving
       Credit Commitment as originally in effect and otherwise duly completed.

                (b) The date, amount, Type, interest rate and duration of
       Interest Period (if applicable) of each Loan made by each Lender to the
       Company, and each payment made on account of the principal thereof,
       shall be recorded by such Lender on its books and,

                                       -23-



       prior to any transfer of any Note evidencing the Loans held by it,
       endorsed by such Lender on the schedule attached to such Note or any
       continuation thereof; PROVIDED that the failure of such Lender to make
       any such recordation or endorsement shall not affect the obligations
       of the Company to make a payment when due of any amount owing
       hereunder or under such Note in respect of such Loans.

                (c) No Lender shall be entitled to have its Notes substituted
       or exchanged for any reason, or subdivided for promissory notes of
       lesser denominations, except in connection with a permitted assignment
       of all or any portion of such Lender's relevant Commitment, Loans and
       Note pursuant to Section 12.7 hereof (and, if requested by any Lender,
       the Company agrees to so exchange any Note).

         2.8. OPTIONAL PREPAYMENTS AND CONVERSIONS OR CONTINUATIONS OF LOANS.
Subject to Section 4.4 hereof, the Company shall have the right to prepay Loans
or to Convert Loans of one Type into Loans of another Type (within the same
Facility) or Continue Loans of one Type as Loans of the same Type (within the
same Facility), at any time or from time to time, PROVIDED that:

                (a) the Company shall give the Administrative Agent notice of
       each such prepayment, Conversion or Continuation as provided in Section
       4.5 hereof (and, upon the date specified in any such notice of
       prepayment, the amount to be prepaid shall become due and payable
       hereunder); and

                (b) any prepayment or Conversion of LIBOR Loans on any day
       other than the last day of an Interest Period for such Loans shall be
       subject to the payment of any compensation payable pursuant to Section
       5.5 hereof.

Notwithstanding the foregoing, and without limiting the rights and remedies
of the Lenders under Section 10 hereof, in the event that any Event of
Default shall have occurred and be continuing, the Administrative Agent may
(and at the request of the Required Lenders shall) suspend the right of the
Company to Convert any Loan into a LIBOR Loan, or to make or Continue any
Loan as a LIBOR Loan, in which event all Loans shall be Converted (on the
last day(s) of the respective Interest Periods therefor) or made or
Continued, as the case may be, as Prime Rate Loans.

Section 3.  PAYMENTS OF PRINCIPAL AND INTEREST.

         3.1. REPAYMENT OF LOANS. The Company hereby promises to pay to the
Administrative Agent for account of each Lender (a) the entire outstanding
principal amount of such Lender's 364-Day Facility Revolving Credit Loans,
and each 364-Day Facility Revolving Credit Loan shall mature, on the 364-Day
Facility Revolving Credit Commitment Termination Date; and (b) the entire
outstanding principal amount of such Lender's Three-Year Facility Revolving
Credit Loans, and each Three-Year Facility Revolving Credit Loan shall
mature, on the Three-Year Facility Revolving Credit Commitment Termination
Date.

         3.2. INTEREST. The Company hereby promises to pay to the Administrative
Agent for account of each Lender interest on the unpaid principal amount of each
Revolving Credit Loan made by such Lender for the period from and including the
date of such Loan to but

                                       -24-



excluding the date such Revolving Credit Loan shall be paid in full, at the
following rates per annum:

                  (a) if such Loan is outstanding as a Prime Rate Loan, the
         Prime Rate (as in effect from time to time) PLUS the Applicable Margin;
         and

                  (b) if such Loan is outstanding as a LIBOR Loan, for each
         Interest Period relating thereto, the Adjusted LIBO Rate for such Loan
         for such Interest Period PLUS the Applicable Margin.

         During any period when an Event of Default shall have occurred and
be continuing and upon notice from the Administrative Agent (provided either
in its discretion or at the request of the Required Lenders) of an election
to charge interest at the applicable Post-Default Rate, the Company hereby
promises to pay to the Administrative Agent for account of each Lender
interest at the applicable Post-Default Rate on (i) each Loan and (ii) any
amount owing hereunder (other than overdue principal of a Loan) that is not
paid when due (whether at stated maturity, by acceleration, by mandatory or
voluntary prepayment or otherwise).

         Accrued interest on each Loan shall be payable in arrears (i) in the
case of a Prime Rate Loan, quarterly on the Quarterly Dates, (ii) in the case
of a LIBOR Loan, on the last day of each Interest Period therefor and, if
such Interest Period is longer than three months, at three-month intervals
following the first day of such Interest Period, and (iii) in the case of any
Loan, upon the payment or prepayment thereof or the Conversion of such Loan
to a Loan of another Type (but only on the principal amount so paid, prepaid
or Converted), except that interest payable at the Post-Default Rate shall be
payable from time to time on demand. Promptly after the determination of any
interest rate provided for herein or any change therein, the Administrative
Agent shall give notice thereof to the Lenders to which such interest is
payable and to the Company.

Section 4.  PAYMENTS; PRO RATA TREATMENT; COMPUTATIONS; ETC.

         4.1.     PAYMENTS.

                  (a) Except to the extent otherwise provided in this Agreement,
         all payments of principal, interest, and other amounts to be made by
         the Company under this Agreement and the Notes, and, except to the
         extent otherwise provided therein, all payments to be made by the
         Obligors under any other Loan Document, shall be made in Dollars, in
         immediately available funds, without deduction, set-off or
         counterclaim, to the Administrative Agent at account number 58386988
         maintained by the Company with the Administrative Agent, or at any
         other account designated in writing by the Administrative Agent, at the
         Principal Office, not later than 1:00 p.m. Boston, Massachusetts time
         on the date on which such payment shall become due (each such payment
         made after such time on such due date to be deemed to have been made on
         the next succeeding Business Day). The Obligors authorize the
         Administrative Agent to debit such account for all such payments.

                  (b) If any such payment owing to any Lender is not made when
         due (beyond any applicable grace period), such Lender may (but shall
         not be obligated to)

                                       -25-



         debit the amount of any such payment to any ordinary deposit account
         of the Company with such Lender (with notice to the Company and the
         Administrative Agent).

                  (c) The Company shall, at the time of making each payment
         under this Agreement or any Note for account of any Lender, subject to
         Section 4.2 specify to the Administrative Agent (which shall so notify
         the intended recipient(s) thereof) the amount payable on the Loans, the
         Facility to which such payment applies, or other amounts payable by the
         Company hereunder to which such payment is to be applied (and in the
         event that the Company fails to so specify, or if an Event of Default
         has occurred and is continuing, the Administrative Agent may distribute
         such payment to the Lenders for application in such manner as it,
         subject to Section 4.2 hereof, may determine to be appropriate).

                  (d) Each payment received by the Administrative Agent under
         this Agreement or any Note for account of any Lender shall be paid by
         the Administrative Agent promptly to such Lender, in immediately
         available funds, for account of such Lender's Applicable Lending Office
         for the Loan or other obligation in respect of which such payment is
         made.

                  (e) If the due date of any payment under this Agreement or any
         Note would otherwise fall on a day that is not a Business Day, such
         date shall be extended to the next succeeding Business Day, and
         interest shall be payable for any principal so extended for the period
         of such extension.

                  (f) Any payment of principal or interest on the Loans not paid
         within ten (10) days after the date such payment is due shall be
         subject to a late charge equal to five percent (5%) of the amount
         overdue.

                  (g) All payments by the Company hereunder and under any of the
         other Loan Documents shall be made without recoupment, setoff or
         counterclaim and free and clear of and without deduction for any taxes,
         levies, imposts, duties, charges, fees, deductions, withholdings,
         compulsory loans, restrictions or conditions of any nature now or
         hereafter imposed or levied by any jurisdiction or any political
         subdivision thereof or taxing or other authority therein unless the
         Company is compelled by law to make such deduction or withholding. If
         any such obligation is imposed upon the Company with respect to any
         amount payable by it hereunder or under any of the other Loan
         Documents, the Company will pay to the Administrative Agent, for the
         account of the Lenders or (as the case may be) the Administrative
         Agent, on the date on which such amount is due and payable hereunder or
         under such other Loan Document, such additional amount in Dollars as
         shall be necessary to enable the Lenders or the Administrative Agent to
         receive the same net amount which the Lenders or the Administrative
         Agent would have received on such due date had no such obligation been
         imposed upon the Company. The Company will deliver promptly to the
         Administrative Agent certificates or other valid vouchers for all taxes
         or other charges deducted from or paid with respect to payments made by
         the Company hereunder or under such other Loan Document.


                                       -26-



         4.2. PRO RATA TREATMENT.  Except to the extent otherwise provided
herein:

                  (a) each borrowing of Loans from the Lenders under Section 2.1
         hereof shall be made from the Lenders, each payment of commitment fee
         under Section 2.4 hereof in respect of Commitments shall be made for
         account of the Lenders, and each termination or reduction of the amount
         of the Commitments under Section 2.3 hereof shall be applied to the
         respective Commitments of the Lenders, pro rata according to the
         amounts of their respective Commitments under the respective Facility;

                  (b) except as otherwise provided in Section 5.4 hereof, LIBOR
         Loans having the same Interest Period shall be allocated pro rata among
         the Lenders according to the amounts of their respective Revolving
         Credit Commitments under the respective Facility (in the case of the
         making of Loans) or their respective Revolving Credit Loans under the
         respective Facility (in the case of Conversions and Continuations of
         Loans);

                  (c) each payment or prepayment of principal of Revolving
         Credit Loans by the Company shall be made for account of the Lenders
         pro rata in accordance with the respective unpaid principal amounts of
         the Loans under the respective Facility held by them; and

                  (d) each payment of interest on Revolving Credit Loans by the
         Company shall be made for account of the Lenders pro rata in accordance
         with the amounts of interest on such Loans under the respective
         Facility then due and payable to the respective Lenders.

         4.3. COMPUTATIONS. Interest on Loans and commitment fees shall be
computed on the basis of a year of 360 days and actual days elapsed, including
the first day but excluding the last day occurring in the period for which
payable.

         4.4. MINIMUM AMOUNTS. Except for Conversions or prepayments made
pursuant to Section 5.4 hereof, each borrowing, Conversion and partial
prepayment of principal of Loans shall be in an aggregate amount equal to
$5,000,000 or an integral multiple of $1,000,000 in excess thereof (borrowings,
Conversions or prepayments of or into Loans of different Types or, in the case
of LIBOR Loans, having different Interest Periods at the same time hereunder to
be deemed separate borrowings, Conversions and prepayments for purposes of the
foregoing, one for each Type or Interest Period).

         4.5. CERTAIN NOTICES. Notices by the Company to the Administrative
Agent of terminations or reductions of the Commitments, of borrowings,
Conversions, Continuations and optional prepayments of Loans, of the respective
Facility, and of Types of Loans and of the duration of Interest Periods shall be
irrevocable and shall be effective only if received by the Administrative Agent
not later than 10:00 a.m. Boston, Massachusetts time (or, in respect of: (i)
borrowings to be made on the Closing Date; (ii) the Conversion into LIBOR Loans
to be effected on December 18, 2000 in the principal amount of up to
$168,000,000 of Loans; or (iii) the borrowing of LIBOR Loans to be effected on
December 19, 2000 in the principal amount of up to $200,000,000 of Loans, not
later than 4:00 p.m. Boston, Massachusetts time) on the number of Business Days
prior to the date of the relevant termination, reduction, borrowing, Conversion,
Continuation or prepayment or the first day of such Interest Period specified
below:


                                       - 27 -





                                                             Number of
                                                             Business
             Notice                                          Days Prior
             ------                                          ----------

                                                          
             Termination or reduction
             of Commitments                                  3

             Borrowing or prepayment of,
             or Conversion into,
             Prime Rate Loans                                1

             Borrowing or prepayment of,
             Conversions into, Continuations
             as, or duration of Interest
             Period for, LIBOR Loans                         3


A notice of borrowing, Conversion, or Continuation may be given at any time when
the sum of the aggregate outstanding Loans and the aggregate requested Loans
exceeds the lesser of the aggregate availabilities or the aggregate Commitments;
PROVIDED, HOWEVER, that Loans outstanding shall never exceed the lesser of the
aggregate availability or the aggregate Commitments. Each such notice of
termination or reduction shall specify the respective Facility and the amount of
the Commitments to be terminated or reduced. Each such notice of borrowing,
Conversion, Continuation or optional prepayment shall specify the amount to be
borrowed, Converted, Continued or prepaid (subject to Section 4.4 hereof) and
Type and the respective Facility of each Loan to be borrowed, Converted,
Continued or prepaid and the date of borrowing, Conversion, Continuation or
optional prepayment (which shall be a Business Day), and shall be in the form,
as applicable, of either EXHIBIT H hereto (for each notice of borrowing),
EXHIBIT I hereto (for each notice of Conversion or Continuation), or EXHIBIT J
hereto (for each notice of prepayment). Each such notice of the duration of an
Interest Period shall specify the Loans to which such Interest Period is to
relate. The Administrative Agent shall promptly notify the Lenders of the
contents of each such notice. In the event that the Company fails to select a
Facility or Type of Loan, or the duration of any Interest Period for any LIBOR
Loan, within the time period and otherwise as provided in this Section 4.5, such
Loan: (i) if then outstanding as a LIBOR Loan, will be automatically Converted
into a Prime Rate Loan under the same Facility as such LIBOR Loan on the last
day of the then current Interest Period for such Loan, unless such Facility was
the 364-Day Facility and the 364-Day Facility Revolving Credit Commitment
Termination Date shall have occurred, in which case it will be made as a Prime
Rate Loan under the Three-Year Facility; or (ii) if not then outstanding, will
be made as, a Prime Rate Loan under the Three-Year Facility.

         4.6. NON-RECEIPT OF FUNDS BY THE ADMINISTRATIVE AGENT; DELINQUENT
LENDERS.

                  (a) Unless the Administrative Agent shall have been notified
         by a Lender or the Company (the "PAYOR") prior to the date on which the
         Payor is to make payment to the Administrative Agent of (in the case of
         a Lender) the proceeds of a Loan to be made by such Lender hereunder or
         (in the case of the Company) a payment to the


                                       - 28 -



        Administrative Agent for account of one or more of the Lenders
        hereunder (such payment being herein called the "REQUIRED PAYMENT"),
        which notice shall be effective upon receipt, that the Payor does
        not intend to make the Required Payment to the Administrative Agent,
        the Administrative Agent may assume that the Required Payment has
        been made and may, in reliance upon such assumption (but shall not
        be required to), make the amount thereof available to the intended
        recipient(s) on such date; and, if the Payor has not in fact made
        the Required Payment to the Administrative Agent and the
        Administrative Agent has made the payment to the recipient(s), the
        recipient(s) of such payment shall, on demand, repay to the
        Administrative Agent the amount so made available together with
        interest thereon in respect of each day during the period commencing
        on the date (the "ADVANCE DATE") such amount was so made available
        by the Administrative Agent until the date the Administrative Agent
        recovers such amount at a rate per annum equal to the Federal Funds
        Rate for such day and, if such recipient(s) shall fail promptly to
        make such payment, the Administrative Agent shall be entitled to
        recover such amount, on demand, from the Payor, together with
        interest as aforesaid, PROVIDED that if neither the recipient(s) nor
        the Payor shall return the Required Payment to the Administrative
        Agent within three Business Days of the date of the notice from the
        Administrative Agent, then the Payor and the recipient(s) shall each
        be obligated to pay interest on the Required Payment as follows:

                                    (i) if the Required Payment shall represent
                  a payment to be made by the Company to the Lenders, the
                  Company and the recipient(s) shall each be obligated
                  retroactively to the Advance Date to pay interest in respect
                  of the Required Payment at the Post-Default Rate (without
                  duplication of the obligation of the Company under Section 3.2
                  hereof to pay interest on the Required Payment at the
                  Post-Default Rate), it being understood that the return by the
                  recipient(s) of the Required Payment to the Administrative
                  Agent shall not limit such obligation of the Company under
                  said Section 3.2 to pay interest at the Post-Default Rate in
                  respect of the Required Payment; and

                                    (ii) if the Required Payment shall represent
                  proceeds of a Loan to be made by the Lenders to the Company,
                  the Payor and the Company shall each be obligated
                  retroactively to the Advance Date to pay interest in respect
                  of the Required Payment pursuant to Section 3.2 hereof
                  (without duplication of the obligation of the Company under
                  Section 3.2 hereof to pay interest on the Required Payment),
                  it being understood that the return by the Company of the
                  Required Payment to the Administrative Agent shall not limit
                  any claim the Company may have against the Payor in respect of
                  such Required Payment.

                  (b) If for any reason any Lender shall fail or refuse to abide
         by its obligations under this Loan Agreement, including, without
         limitation, its obligation to make available to Administrative Agent
         its share of any Revolving Credit Loans, expenses, or setoff (a
         "Delinquent Lender"), any non-delinquent Lender shall have the right,
         but not the obligation, in its respective, sole and absolute
         discretion, to acquire (x) for no cash consideration (PRO RATA, based
         on the respective Commitments of those Lenders electing to exercise
         such right) the Delinquent Lender's Commitment to fund future Revolving
         Credit Loans; and (y) for consideration equal to the amount of the


                                       - 29 -



         outstanding Revolving Credit Loans from such Lender (PRO RATA, based on
         the respective Commitments of those Lenders electing to exercise such
         right) the Delinquent Lender's rights with respect to outstanding
         Revolving Credit Loans (the rights purchased under clauses (x) and (y),
         the "Purchased Rights"), but only if, in the aggregate, all of the
         Delinquent Lender's rights with respect to outstanding Revolving Credit
         Loans and Commitments are acquired hereunder by one or more
         non-delinquent Lender(s). Upon any such purchase of the PRO RATA share
         of any Delinquent Lender's Purchased Rights, the Delinquent Lender's
         rights with respect to outstanding Revolving Credit Loans, Commitment,
         share in future Revolving Credit Loans, and rights under the Loan
         Documents with respect thereto shall terminate on the day of purchase
         (other than indemnification rights that survive termination of the
         Commitments under Section 12.8 hereof and rights to receive accrued but
         unpaid interest and fees through the date of purchase), and the
         Delinquent Lender shall promptly execute all documents reasonably
         requested to surrender and transfer such interests (other than
         indemnification rights that survive termination of the Commitments
         under Section 12.8 hereof and rights to receive accrued but unpaid
         interest and fees through the date of purchase), including, if so
         requested, a Notice of Assignment (provided that the assignment fee in
         connection with such Notice of Assignment shall not be charged).

         4.7.     SHARING OF PAYMENTS, ETC.

                  (a) Each Obligor agrees that, in addition to (and without
         limitation of) any right of set-off, banker's lien or counterclaim a
         Lender may otherwise have, each Lender shall be entitled, at its option
         (to the fullest extent permitted by law), to set off and apply any
         deposit (general or special, time or demand, provisional or final), or
         other indebtedness, held by it for the credit or account of such
         Obligor at any of its offices, in Dollars or in any other currency,
         against any principal of or interest on any of such Lender's Loans, or
         any other amount payable to such Lender hereunder, that is not paid
         when due (regardless of whether such deposit or other indebtedness are
         then due to such Obligor and of the existence or adequacy of any
         security therefor), in which case it shall promptly notify such Obligor
         and the Administrative Agent thereof, PROVIDED that such Lender's
         failure to give such notice shall not affect the validity thereof.

                  (b) If any Lender shall obtain from any Obligor payment of any
         principal of or interest on any Loan owing to it or payment of any
         other amount under this Agreement or any other Loan Document through
         the exercise any right of set-off, banker's lien or counterclaim or
         similar right or otherwise (other than from the Administrative Agent as
         provided herein), and, as a result of such payment, such Lender shall
         have received a greater percentage of the principal of or interest on
         the Loans or such other amounts then due hereunder or thereunder by
         such Obligor to such Lender than the percentage received by any other
         Lender, it shall promptly purchase from such other Lenders
         participations in (or, if and to the extent specified by such Lender,
         direct interests in) the Loans or such other amounts, respectively,
         owing to such other Lenders (or in interest due thereon, as the case
         may be) in such amounts, and make such other adjustments from time to
         time as shall be equitable, to the end that all the Lenders shall share
         the benefit of such excess payment (net of any expenses that may be
         incurred by such Lender in obtaining or preserving such excess payment)
         pro rata in accordance with the unpaid principal of and/or interest on
         the Loans or such other amounts, respectively,


                                       - 30 -



        owing to each of the Lenders. To such end all the Lenders shall make
        appropriate adjustments among themselves (by the resale of
        participations sold or otherwise) if such payment is rescinded or
        must otherwise be restored.

                  (c) The Company agrees that any Lender so purchasing such a
         participation (or direct interest) may exercise all rights of set-off,
         banker's lien, counterclaim or similar rights with respect to such
         participation as fully as if such Lender were a direct holder of Loans
         or other amounts (as the case may be) owing to such Lender in the
         amount of such participation.

                  (d) Nothing contained herein shall require any Lender to
         exercise any such right or shall affect the right of any Lender to
         exercise, and retain the benefits of exercising, any such right with
         respect to any other indebtedness or obligation of any Obligor. If,
         under any applicable bankruptcy, insolvency or other similar law, any
         Lender receives a secured claim in lieu of a set-off to which this
         Section 4.7 applies, such Lender shall, to the extent practicable,
         exercise its rights in respect of such secured claim in a manner
         consistent with the rights of the Lenders entitled under this Section
         4.7 to share in the benefits of any recovery on such secured claim.

Section 5.  YIELD PROTECTION, ETC.

         5.1.     ADDITIONAL COSTS.

                  (a) The Company shall pay directly to each Lender from time to
         time such amounts as such Lender may determine to be necessary to
         compensate such Lender for any costs that such Lender determines are
         attributable to its making or maintaining of any LIBOR Loans or its
         obligation to make any LIBOR Loans hereunder, or any reduction in any
         amount receivable by such Lender hereunder in respect of any of such
         Loans or such obligation (such increases in costs and reductions in
         amounts receivable being herein called "ADDITIONAL COSTS"), resulting
         from any Regulatory Change that:

                                    (i) shall subject any Lender (or its
                  Applicable Lending Office for any of such Loans) to any tax,
                  duty or other charge in respect of such Loans or its Note or
                  changes the basis of taxation of any amounts payable to such
                  Lender under this Agreement or its Note in respect of any of
                  such Loans (excluding any Taxes based on net income or in lieu
                  of net income imposed on such Lender by the jurisdiction in
                  which such Lender has its principal office or its Applicable
                  Lending Office); or

                                    (ii) imposes or modifies any reserve,
                  special deposit or similar requirements (other than any
                  thereof, including, without limitation, the Reserve
                  Requirement, utilized in the determination of the Adjusted
                  LIBO Rate or LIBO Rate for such Loan) relating to any
                  extensions of credit or other assets of, or any deposits with
                  or other liabilities of, such Lender (including, without
                  limitation, any of such Loans or any deposits referred to in
                  the definition of "LIBO Rate" in Section 1.1 hereof), or any
                  commitment of such Lender (including, without limitation, the
                  Commitments of such Lender hereunder); or


                                      - 31 -



                                    (iii) imposes any other condition affecting
                  this Agreement or its Note (or any of such extensions of
                  credit or liabilities) or its Commitment.

If any Lender requests compensation from the Company under this Section 5.1(a),
the Company may, by notice to such Lender (with a copy to the Administrative
Agent), suspend the obligation of such Lender thereafter to make or Continue
LIBOR Loans, or to Convert Prime Rate Loans into LIBOR Loans, until the
Regulatory Change giving rise to such request ceases to be in effect (in which
case the provisions of Section 5.4 hereof shall be applicable), PROVIDED that
such suspension shall not affect the right of such Lender to receive the
compensation so requested.

                  (b) Without limiting the effect of the provisions of paragraph
         (a) of this Section 5.1, in the event that, by reason of any Regulatory
         Change, any Lender either (i) incurs Additional Costs based on or
         measured by the excess above a specified level of the amount of a
         category of deposits or other liabilities of such Lender that includes
         deposits by reference to which the interest rate on LIBOR Loans is
         determined as provided in this Agreement or a category of extensions of
         credit or other assets of such Lender that includes LIBOR Loans or (ii)
         becomes subject to restrictions on the amount of such a category of
         liabilities or assets that it may hold, then, if such Lender so elects
         by notice to the Company (with a copy to the Administrative Agent), the
         obligation of such Lender to make or Continue, or to Convert Prime Rate
         Loans into, LIBOR Loans hereunder shall be suspended until such
         Regulatory Change ceases to be in effect (in which case the provisions
         of Section 5.4 hereof shall be applicable).

                  (c) Without limiting the effect of the foregoing provisions of
         this Section 5.1 (but without duplication), the Company shall pay
         directly to each Lender from time to time on request such amounts as
         such Lender may determine to be necessary to compensate such Lender
         (or, without duplication, the bank holding company of which such Lender
         is a subsidiary) for any costs that it determines are attributable to
         the maintenance by such Lender (or any Applicable Lending Office or
         such bank holding company), pursuant to any law or regulation or any
         interpretation, directive or request (whether or not having the force
         of law and whether or not failure to comply therewith would be
         unlawful) of any court or governmental or monetary authority (i)
         following any Regulatory Change or (ii) implementing any risk-based
         capital guideline or other requirement (whether or not having the force
         of law and whether or not the failure to comply therewith would be
         unlawful) hereafter issued by any government or governmental or
         supervisory authority implementing at the national level the Basle
         Accord, of capital in respect of its Commitments or Loans (such
         compensation to include, without limitation, an amount equal to any
         reduction of the rate of return on assets or equity of such Lender (or
         any Applicable Lending Office or such bank holding company) to a level
         below that which such Lender (or any Applicable Lending Office or such
         bank holding company) could have achieved but for such law, regulation,
         interpretation, directive or request).

                  (d) Each Lender shall notify the Company of any event
         occurring after the date hereof entitling such Lender to compensation
         under paragraph (a) or (c) of this Section 5.1 as promptly as
         practicable, but in any event within 45 days, after such Lender obtains
         actual knowledge thereof; PROVIDED that if (i) any Lender fails to give


                                      - 32 -



         such notice within 45 days after it obtains actual knowledge of such an
         event, such Lender shall, with respect to compensation payable pursuant
         to this Section 5.1 in respect of any costs resulting from such event,
         only be entitled to payment under this Section 5.1 for costs incurred
         from and after the date 45 days prior to the date that such Lender does
         give such notice and (ii) each Lender will designate a different
         Applicable Lending Office for the Loans of such Lender affected by such
         event if such designation will avoid the need for, or reduce the amount
         of, such compensation and will not, in the reasonable opinion of such
         Lender, be disadvantageous to such Lender (including, without
         limitation, by reason of any economic, legal or regulatory cost or
         disadvantage that such Lender may bear or suffer by reason of such
         designation). Each Lender will furnish to the Company a certificate
         setting forth in reasonable detail the basis and amount of each request
         by such Lender for compensation under paragraph (a) or (c) of this
         Section 5.1. Determinations and allocations by any Lender for purposes
         of this Section 5.1 of the effect of any Regulatory Change pursuant to
         paragraph (a) or (b) of this Section 5.1, or of the effect of capital
         maintained pursuant to paragraph (c) of this Section 5.1, on its costs
         or rate of return of maintaining Loans or its obligation to make Loans,
         or on amounts receivable by it in respect of Loans, and of the amounts
         required to compensate such Lender under this Section 5.1, shall be
         conclusive, PROVIDED that such determinations and allocations are made
         on a reasonable basis.

         5.2. LIMITATION ON TYPES OF LOANS. Anything herein to the contrary
notwithstanding, if, on or prior to the determination of any LIBO Rate for any
Interest Period:

                  (a) the Administrative Agent determines, which determination
         shall be conclusive, that quotations of interest rates for the relevant
         deposits referred to in the definition of "LIBO Rate" in Section 1.1
         hereof are not being provided in the relevant amounts or for the
         relevant maturities for purposes of determining rates of interest for
         LIBOR Loans as provided herein; or

                  (b) the Required Lenders determine which determination shall
         be conclusive, and notify (or notifies, as the case may be) the
         Administrative Agent that the relevant rates of interest referred to in
         the definition of "LIBO Rate" in Section 1.1 hereof upon the basis of
         which the rate of interest for LIBOR Loans for such Interest Period is
         to be determined do not adequately and fairly reflect the cost to such
         Lenders of making or maintaining LIBOR Loans for such Interest Period;

then the Administrative Agent shall give the Company and each Lender prompt
notice thereof and, so long as such condition remains in effect, the Lenders
shall be under no obligation to make additional LIBOR Loans, to Continue LIBOR
Loans or to Convert Prime Rate Loans into LIBOR Loans, and the Company shall, on
the last day(s) of the then current Interest Period(s) for the outstanding LIBOR
Loans, either prepay such Loans or Convert such Loans into Prime Rate Loans in
accordance with Section 2.8 hereof.

         5.3. ILLEGALITY. Notwithstanding any other provision of this Agreement,
in the event that it becomes unlawful for any Lender or its Applicable Lending
Office to honor its obligation to make or maintain LIBOR Loans hereunder (and,
in the sole opinion of such Lender, the designation of a different Applicable
Lending Office would either not avoid such unlawfulness or would be
disadvantageous to such Lender), then such Lender shall promptly


                                      - 33 -



notify the Company thereof (with a copy to the Administrative Agent) and such
Lender's obligation to make or Continue, or to Convert Loans of any other
Type into, LIBOR Loans shall be suspended until such time as such Lender may
again make and maintain LIBOR Loans (in which case the provisions of Section
5.4 hereof shall be applicable).

         5.4. TREATMENT OF AFFECTED LOANS. If the obligation of any Lender to
make LIBOR Loans or to Continue, or to Convert Prime Rate Loans into, LIBOR
Loans shall be suspended pursuant to Section 5.1 or 5.3 hereof, such Lender's
LIBOR Loans shall be automatically Converted into Prime Rate Loans on the last
day(s) of the then current Interest Period(s) for LIBOR Loans (or, in the case
of a Conversion required by Section 5.1(b) or 5.3 hereof, on such earlier date
as is required pursuant to applicable law or regulation and as such Lender may
specify to the Company with a copy to the Administrative Agent) and, unless and
until such Lender gives notice as provided below that the circumstances
specified in Section 5.1 or 5.3 hereof that gave rise to such Conversion no
longer exist:

                  (a) to the extent that such Lender's LIBOR Loans have been so
         Converted, all payments and prepayments of principal that would
         otherwise be applied to such Lender's LIBOR Loans shall be applied
         instead to its Prime Rate Loans; and

                  (b) all Loans that would otherwise be made or Continued by
         such Lender as LIBOR Loans shall be made or Continued instead as Prime
         Rate Loans, and all Prime Rate Loans of such Lender that would
         otherwise be Converted into LIBOR Loans shall remain as Prime Rate
         Loans.

If such Lender gives notice to the Company with a copy to the Administrative
Agent that the circumstances specified in Section 5.1 or 5.3 hereof that gave
rise to the Conversion of such Lender's LIBOR Loans pursuant to this Section 5.4
no longer exist (which such Lender agrees to do promptly upon such circumstances
ceasing to exist) at a time when LIBOR Loans made by other Lenders are
outstanding, such Lender's Prime Rate Loans shall be automatically Converted, on
the first day(s) of the next succeeding Interest Period(s) for such outstanding
LIBOR Loans, to the extent necessary so that, after giving effect thereto, all
Loans held by the Lenders holding LIBOR Loans and by such Lender are held pro
rata (as to principal amounts, Types and Interest Periods) in accordance with
their respective Commitments.

         5.5. COMPENSATION. The Company shall pay to the Administrative Agent
for account of each Lender, upon the request of such Lender through the
Administrative Agent, such amount or amounts as shall be sufficient (in the
reasonable opinion of such Lender) to compensate it for any loss, cost or
expense that such Lender determines is attributable to:

                  (a) any payment, mandatory or optional prepayment or
         Conversion of a LIBOR Loan made by such Lender for any reason
         (including, without limitation, the acceleration of the Loans pursuant
         to Section 10 hereof) on a date other than the last day of the Interest
         Period for such Loan; or

                  (b) any failure by the Company for any reason (including,
         without limitation, the failure of any of the conditions precedent
         specified in Section 7 hereof to be satisfied) to borrow, Continue or
         Convert a LIBOR Loan from such Lender on the


                                       - 34 -



        date for such borrowing, Continuation or Conversion specified in the
        relevant notice given pursuant to Sections 2.2 and 4.5 hereof.

Without limiting the effect of the preceding sentence, such compensation shall,
if so requested, include an amount equal to the product of: (a) the amount so
paid, prepaid, Converted or not borrowed times (b) the excess of (i) the rate of
interest that otherwise would have accrued on the principal amount so paid,
prepaid, Converted or not borrowed for the period from the date of such payment,
prepayment, Conversion or failure to borrow to the last day of the then current
Interest Period for such Loan (or, in the case of a failure to borrow, the
Interest Period for such Loan that would have commenced on the date specified
for such borrowing) at the applicable rate of interest for such Loan provided
for herein (excluding, however, any Applicable Margin included therein) less
(ii) the rate of interest that otherwise would have accrued on such principal
amount at a rate per annum equal to the interest component of the amount such
Lender would have bid in the London interbank market (for Dollar deposits of
leading banks in amounts comparable to such principal amount and with maturities
comparable to such period (as reasonably determined by such Lender), which
product shall be multiplied by a fraction the numerator of which is the number
of days from the date of such occurrence to the last day of the applicable
Interest Period and the denominator of which is 360 days.

         5.6. RATE SELECTION. If the Company has provided a notice of borrowing
under Section 4.5 hereof and any Lender determines (which determination shall be
conclusive and binding on the Company) that:

                  (a) deposits of the necessary amount for the selected Interest
         Period are not available to such Lender in either the London interbank
         market or the market for Federal funds transactions or, by reason of
         circumstances affecting such markets, adequate and reasonable means do
         not exist for ascertaining the LIBO Rate or the Federal Funds Rate for
         such Interest Period; or

                  (b) the LIBO Rate or the Federal Funds Rate, as applicable,
         will not adequately and fairly reflect the cost to such Lender of
         making or funding a Loan for such Interest Period; or

                  (c) the making or funding of Loans has become impracticable as
         a result of any event occurring after the date of this Agreement which,
         in the opinion of such Lender, materially and adversely affects such
         Loans or the London interbank market or the market for Federal funds
         transactions;

then such Lender shall notify the Company of this condition and of the rate that
the Lender has selected to apply to such Loan pursuant to the following
sentence, provided, however, that the Company shall have the opportunity to
withdraw such notice of borrowing prior to the making of the Loan on the date
specified in the notice. If, after such notice from the Lender, the Company does
not withdraw such notice of borrowing prior to the making of the Loan, then any
notice of borrowing shall be deemed to be a notice to request a borrowing of
such Loan at such higher rate per annum, if any, which in such Lender's opinion
will adequately fairly compensate such Lender for the cost to such Lender of
making or funding such Loan plus the Applicable Margin under this Agreement; or
if such Lender determines that no such rate exists, then such Lender shall
promptly notify the Agent and shall not be obligated to fund the Loan.


                                       - 35 -



Section 6.  GUARANTEE.

         6.1. GUARANTEE. The Subsidiary Guarantors hereby jointly and severally
guarantee to each Lender and each Agent and their respective successors and
assigns the prompt payment in full when due (whether at stated maturity, by
acceleration or otherwise) of the principal of and interest on the Loans made by
the Lenders to, and the Notes held by each Lender of, the Company and all other
amounts from time to time owing to the Lenders or any Agent by the Company under
this Agreement and under the Notes and by any Obligor under any of the other
Loan Documents, in each case strictly in accordance with the terms thereof (such
obligations being herein collectively called the "GUARANTEED OBLIGATIONS"). The
Subsidiary Guarantors hereby further jointly and severally agree that if the
Company shall fail to pay in full when due (whether at stated maturity, by
acceleration or otherwise) any of the Guaranteed Obligations, the Subsidiary
Guarantors will promptly pay the same, without any demand or notice whatsoever,
and that in the case of any extension of time of payment or renewal of any of
the Guaranteed Obligations, the same will be promptly paid in full when due
(whether at extended maturity, by acceleration or otherwise) in accordance with
the terms of such extension or renewal.

         6.2. OBLIGATIONS UNCONDITIONAL. The obligations of each Subsidiary
Guarantor under Section 6.1 hereof are absolute and unconditional, joint and
several, irrespective of the value, genuineness, validity, regularity or
enforceability of the obligations of the Company or any Obligor (other than such
Subsidiary Guarantor) under this Agreement, the Notes, the other Loan Documents
or any other agreement or instrument referred to herein or therein, or any
substitution, release or exchange of any other guarantee of or security for any
of the Guaranteed Obligations, and, to the fullest extent permitted by
applicable law, irrespective of any other circumstance whatsoever that might
otherwise constitute a legal or equitable discharge or defense of a surety or
guarantor, it being the intent of this Section 6.2 that the obligations of the
Subsidiary Guarantors hereunder shall be absolute and unconditional, joint and
several, under any and all circumstances. Without limiting the generality of the
foregoing, it is agreed that the occurrence of any one or more of the following
shall not alter or impair the liability of the Subsidiary Guarantors hereunder
which shall remain absolute and unconditional as described above:

                                    (i) at any time or from time to time,
                  without notice to the Subsidiary Guarantors, the time for any
                  performance of or compliance with any of the Guaranteed
                  Obligations shall be extended, or such performance or
                  compliance shall be waived;

                                    (ii) any of the acts mentioned in any of the
                  provisions of this Agreement or the Notes or any other
                  agreement or instrument referred to herein or therein shall be
                  done or omitted;

                                    (iii) the maturity of any of the Guaranteed
                  Obligations shall be accelerated, or any of the Guaranteed
                  Obligations shall be modified, supplemented or amended in any
                  respect, or any right under this Agreement or the Notes or any
                  other agreement or instrument referred to herein or therein
                  shall be waived or any other guarantee of any of the
                  Guaranteed Obligations or any


                                       - 36 -



                  security therefor shall be released or exchanged in whole
                  or in part or otherwise dealt with; or

                                    (iv) any lien or security interest granted
                  to, or in favor of, any Agent or Agents or any Lender or
                  Lenders as security for any of the Guaranteed Obligations
                  shall fail to be perfected.

The Subsidiary Guarantors hereby expressly waive diligence, presentment, demand
of payment, protest and all notices whatsoever, and any requirement that any
Agent or any Lender exhaust any right, power or remedy or proceed against the
Company under this Agreement or the Notes or the other Loan Documents or any
other agreement or instrument referred to herein or therein, or against any
other Person under any other guarantee of, or security for, any of the
Guaranteed Obligations.

         6.3. REINSTATEMENT. The obligations of the Subsidiary Guarantors under
this Section 6 shall be automatically reinstated if and to the extent that for
any reason any payment by or on behalf of the Company in respect of the
Guaranteed Obligations is rescinded or must be otherwise restored by any holder
of any of the Guaranteed Obligations, whether as a result of any proceedings in
bankruptcy or reorganization or otherwise and the Subsidiary Guarantors jointly
and severally agree that they will indemnify each Agent and each Lender on
demand for all reasonable costs and expenses (including, without limitation,
fees of counsel) incurred by such Agent or such Lender in connection with such
rescission or restoration, including any such costs and expenses incurred in
defending against any claim alleging that such payment constituted a preference,
fraudulent transfer or similar payment under any bankruptcy, insolvency or
similar law.

         6.4. SUBROGATION. Each Subsidiary Guarantor hereby agrees that, until
the payment and satisfaction in full of all Guaranteed Obligations and the
expiration and termination of the Commitments of the Lenders under this
Agreement, such Subsidiary Guarantor shall not exercise any right or remedy
arising by reason of any performance by such Subsidiary Guarantor of its
guarantee in Section 6.1 hereof, whether by subrogation or otherwise, against
the Company or any other Obligor or any other guarantor of any of the Guaranteed
Obligations or any security for any of the Guaranteed Obligations.

         6.5. REMEDIES. The Subsidiary Guarantors jointly and severally agree
that, as between the Subsidiary Guarantors and the Lenders, the obligations of
the Company under this Agreement and the Notes may be declared to be forthwith
due and payable as provided in Section 10 hereof (and shall be deemed to have
become automatically due and payable in the circumstances provided in said
Section 10(g) or (h)) for purposes of Section 6.1 hereof notwithstanding any
stay, injunction or other prohibition preventing such declaration (or such
obligations from becoming automatically due and payable) as against the Company
and that, in the event of such declaration (or such obligations being deemed to
have become automatically due and payable), such obligations (whether or not due
and payable by the Company) shall forthwith become due and payable by the
Subsidiary Guarantors for purposes of said Section 6.1.

         6.6. CONTINUING GUARANTEE. The guarantee in this Section 6 is a
continuing guarantee, and shall apply to all Guaranteed Obligations whenever
arising.


                                       - 37 -



         6.7. RIGHTS OF CONTRIBUTION. The Subsidiary Guarantors hereby agree, as
between themselves, that if any Subsidiary Guarantor (an "EXCESS FUNDING
GUARANTOR") shall pay Guaranteed Obligations in excess of such Excess Funding
Guarantor's Pro Rata Share (as defined below) of such Guaranteed Obligations
(such excess payment, an "EXCESS PAYMENT"), each other Subsidiary Guarantor
shall, on demand of such Excess Funding Guarantor (but subject to the next
sentence hereof), pay to such Excess Funding Guarantor an amount equal to such
other Subsidiary Guarantor's Pro Rata Share (such Pro Rata Share, for the
purpose of determining the amount due to the Excess Funding Guarantor under this
Section 6.7, to be determined without reference to the Excess Funding Guarantor)
of such Excess Payment. The payment obligation of each other Subsidiary
Guarantor to an Excess Funding Guarantor under this Section 6.7 shall be
subordinate and subject in right of payment to the prior payment in full of the
Obligations, and such Excess Funding Guarantor shall not exercise any right or
remedy with respect to such Excess Payment until payment and satisfaction in
full of the Obligations. For the purposes hereof, "PRO RATA SHARE" shall mean,
with respect to each Subsidiary Guarantor, the ratio (expressed as a percentage)
of (a) the net worth of such Subsidiary Guarantor (determined on an
unconsolidated basis in accordance with GAAP as of the last day of the fiscal
quarter of such Subsidiary Guarantor most recently ended prior to the date such
Person became a Subsidiary Guarantor) to (b) the sum of the amounts determined
pursuant to clause (a) for all of the Subsidiary Guarantors.

         6.8. LIMITATION ON GUARANTEE OBLIGATIONS. In any action or proceeding
involving any state corporate or partnership law, or any state or Federal
bankruptcy, insolvency, reorganization or other law affecting the rights of
creditors generally, if the obligations of any Subsidiary Guarantor under
Section 6.1 hereof would otherwise, taking into account the provisions of
Section 6.7 hereof, be held or determined to be void, invalid or unenforceable,
or subordinated to the claims of any other creditors, on account of the amount
of its liability under said Section 6.1, then, notwithstanding any other
provision hereof to the contrary, the amount of such liability shall, without
any further action by such Subsidiary Guarantor, any Lender, any Agent or any
other Person, be automatically limited and reduced to the highest amount that is
valid and enforceable and not subordinated to the claims of other creditors as
determined in such action or proceeding.

Section 7.  CONDITIONS PRECEDENT.

         7.1. INITIAL LOAN. The obligation of any Lender to make its initial
Loan hereunder is subject to the satisfaction of each of the following
conditions (with each document being satisfactory to each Agent and each Lender
in form and substance):

                  (a) CORPORATE DOCUMENTS. The receipt by the Administrative
         Agent of (i) certified copies of the charter and by-laws (or equivalent
         constitutional documents) of each Obligor and Genzyme Securities
         Corporation, (ii) a long-form good standing certificate issued by the
         Secretary of State of the jurisdiction of incorporation or organization
         of each Obligor and Genzyme Securities Corporation and (iii) certified
         copies of all corporate or partnership authority for each Obligor
         (including, without limitation, board of director resolutions and
         evidence of the incumbency, including specimen signatures, of officers)
         with respect to the execution, delivery and performance of such of the
         Loan Documents to which such Obligor is intended to be a party and each
         other document to be delivered by such Obligor from time to time in
         connection


                                       - 38 -



         herewith and the extensions of credit hereunder (and each Agent and
         each Lender may conclusively rely on such certificate until it
         receives notice in writing from such Obligor to the contrary).

                  (b) OFFICER'S CERTIFICATE. The receipt by the Administrative
         Agent of a certificate of a senior officer of the Company, dated the
         Closing Date, to the effect set forth in the first sentence of Section
         7.2 hereof.

                  (c) BORROWING NOTICE. The receipt by the Administrative Agent
         of the notice of borrowing required by Sections 2.2 and 4.5 hereof in
         the form of EXHIBIT H.

                  (d) OPINIONS OF COUNSEL TO THE OBLIGORS. The receipt by the
         Administrative Agent of an opinion, dated the Closing Date, of Palmer &
         Dodge LLP, special counsel to the Obligors, substantially in the form
         of EXHIBIT C hereto and covering such other matters as any Agent or any
         Lender may reasonably request.

                  (e) NOTES. The receipt by the Administrative Agent of Notes,
         duly completed and executed for each Lender.

                  (f) PLEDGE AGREEMENT. The receipt by the Administrative Agent
         of the Pledge Agreement in the form of EXHIBIT G, together with the
         certificates for all shares of capital stock of Genzyme Securities
         Corporation pledged thereunder and undated executed stock powers.

                  (g) SEARCH RESULTS. The receipt by the Administrative Agent of
         results satisfactory to the Administrative Agent of UCC, Federal and
         state tax lien and judgment searches conducted by a search firm
         acceptable to the Administrative Agent with respect to each Obligor in
         each jurisdiction specified by the Administrative Agent.

                  (h) INSURANCE. The receipt by the Administrative Agent of (i)
         certificates of insurance evidencing the existence of all insurance
         required to be maintained pursuant to Section 9.4 hereof and (ii) a
         certificate of a senior financial officer of the Company stating that
         the insurance obtained by it in accordance with the requirements of
         said Section 9.4 is in full force and effect and that all premiums then
         due and payable thereon have been paid.

                  (i) REPAYMENT OF EXISTING INDEBTEDNESS. Evidence that the
         principal of and interest on, and all other amounts owing in respect
         of, the Indebtedness (including, without limitation, any contingent or
         other amounts payable in respect of letters of credit) indicated on
         SCHEDULE 8.12A hereto that is to be repaid on the Closing Date shall
         have been (or shall be simultaneously) paid in full, that any
         commitments to extend credit under the agreements or instruments
         relating to such Indebtedness shall have been canceled or terminated
         and that all Guarantees in respect of, and all Liens securing, any such
         Indebtedness shall have been released (or arrangements for such release
         satisfactory to the Required Lenders shall have been made); in
         addition, the Administrative Agent shall have received from any Person
         holding any Lien securing any such Indebtedness, such Uniform
         Commercial Code termination statements, mortgage releases and other
         instruments, in each case in proper form for recording, as the
         Administrative Agent shall


                                       - 39 -



         have requested to release and terminate of record the Liens securing
         such Indebtedness (or arrangements for such release and termination
         satisfactory to the Required Lenders shall have been made).

                  (j) NO ADVERSE LITIGATION OR PROCEEDING. The receipt by the
         Administrative Agent of a certificate of a senior officer of the
         Company to the effect that, on and as of the Closing Date and except as
         disclosed in SCHEDULE 8.3 hereto, no litigation or proceeding shall
         exist or (to the Company's knowledge) be threatened against the Company
         or any of its Subsidiaries, and, to the Company's knowledge, no law or
         regulation shall have been proposed (unless withdrawn) that could
         reasonably be expected to (i) have a Material Adverse Effect, (ii)
         materially and adversely affect the ability of the Obligors to perform
         their respective obligations under this Agreement or the other Loan
         Documents, (iii) materially and adversely affect the rights and
         remedies of the Agents and the Lenders under this Agreement or the Loan
         Documents or (iv) purport to adversely affect the Revolving Credit
         Loans or Commitments.

                  (k) CONSENTS, ETC. The receipt by the Administrative Agent of
         a certificate of a senior officer of the Company to the effect that, on
         and as of the Closing Date, all necessary governmental and third party
         consents and approvals in connection with the transactions contemplated
         by this Agreement have been obtained and remain in effect and that all
         applicable waiting periods have expired.

                  (l) PAYMENT OF FEES. The payment by the Company of such fees
         as the Company shall have agreed to pay or deliver to any Lender or any
         Agent in connection herewith, including, without limitation, any and
         all arrangement and administrative, syndication, or documentation fees
         due to any Agent, up-front fees due to the Lenders, and the reasonable
         fees and expenses of Brown, Rudnick, Freed & Gesmer, special counsel to
         Fleet in connection with the negotiation, preparation, execution and
         delivery of this Agreement and the Notes and the other Loan Documents
         and the making of the extensions of credit hereunder (to the extent
         that statements for such fees and expenses have been delivered to the
         Company).

                  (m) INITIAL ACQUISITION DOCUMENTS. (i) The Company shall have
         made available to the Lenders signed copies of the Initial Acquisition
         Documents; (ii) the Administrative Agent shall have received the
         Company's certificate that the Initial Acquisition Documents most
         recently made available to the Lenders have not been amended, and that
         the transactions contemplated under the terms thereof have been
         consummated prior to or will be consummated contemporaneously with the
         Closing Date; and (iii) the Company shall have complied with Section
         9.13 hereof with respect to the entity that has become a Material
         Subsidiary by virtue of the Initial Acquisition.

                  (n) PRIOR CREDIT AGREEMENT. Either: (i) the Prior Credit
         Agreement Parties shall have delivered a written agreement executed by
         all of them terminating the Prior Agreement as of the Closing Date, in
         the form of EXHIBIT K hereto, and the Company shall have made all
         payments required thereunder; or (ii) the Company shall have delivered
         to the Administrative Agent (as defined under the Prior Credit
         Agreement) a notice of termination of the credit facilities under the
         Prior Credit Agreement, not less


                                       - 40 -



         than three (3) Business Days (as defined in the Prior Credit
         Agreement) prior to the Closing Date hereof.

                  (o) OTHER DOCUMENTS. Such other documents as any Agent or any
         Lender or special counsel to Fleet may reasonably request.

                  (p) PRE-COMMITMENT FEE. The Company shall pay to the
         Administrative Agent for the account of each Lender a pre-commitment
         fee, for the period from and including December 7, 2000 to but not
         including the Closing Date, at a rate per annum equal to 0.10% of such
         Lender's Commitment (for the purposes only of calculating the
         pre-commitment fee under this Section 7.1(p), each Lender's Commitment
         shall be calculated as if the Post-Second Acquisition 364-Day Facility
         Revolving Credit Commitments and the Post-Second Acquisition Three-Year
         Facility Revolving Credit Commitments were in effect).


         7.2. INITIAL AND SUBSEQUENT EXTENSIONS OF CREDIT. The obligation of any
Lender to make any Loan or otherwise extend any credit to the Company upon the
occasion of each borrowing or other extension of credit hereunder is subject to
the further conditions precedent that, both immediately prior to such borrowing
or other extension of credit and also after giving effect thereto and to the
intended use thereof:

                  (a) no Default shall have occurred and be continuing; and

                  (b) the representations and warranties made by the Company in
         Section 8 hereof, and by each Obligor in each of the other Loan
         Documents to which it is a party, shall be true and complete in all
         material respects on and as of the date of the making of such Loan or
         other extension of credit with the same force and effect as if made on
         and as of such date (or, if any such representation or warranty is
         expressly stated to have been made as of a specific date, as of such
         specific date).

Each notice of borrowing by the Company hereunder shall constitute a
certification by the Company to the effect set forth in the preceding sentence
(both as of the date of such notice or request and, unless the Company otherwise
notifies the Administrative Agent prior to the date of such borrowing or
issuance, as of the date of such borrowing or issuance).

Section 8. REPRESENTATIONS AND WARRANTIES. The Company represents and warrants
to the Agents and the Lenders that:

         8.1. EXISTENCE. Each of the Company and the Material Subsidiaries: (a)
is a corporation, partnership, limited liability company or other entity duly
organized, validly existing and in good standing under the laws of the
jurisdiction of its organization; (b) has all requisite corporate, partnership
or other power, and has all material governmental licenses, authorizations,
consents and approvals necessary to own its assets and carry on its business as
now being or as proposed to be conducted, except to the extent that the failure
to have any such license, authorization, consent or approval would not
reasonably be expected (either individually or in the aggregate) to have a
Material Adverse Effect; and (c) is qualified to do business and is in good
standing in all jurisdictions in which the nature of the business


                                       - 41 -



conducted by it makes such qualification necessary and where failure so to
qualify would not reasonably be expected (either individually or in the
aggregate) to have a Material Adverse Effect.

         8.2. FINANCIAL CONDITION. The Company has heretofore furnished to each
of the Lenders the audited Consolidated balance sheet of the Company as at
December 31, 1999 and the related Consolidated statements of earnings,
shareholders' equity and cash flows of the Company for the fiscal year ended on
said date, with the report thereon of PricewaterhouseCoopers, and the unaudited
Consolidated balance sheet of the Company as at September 30, 2000, and the
related unaudited Consolidated statements of income and cash flows for the
period ended on said date. All such financial statements fairly present in all
material respects the Consolidated financial position of the Company as at said
dates and the Consolidated results of its operations for the fiscal year and
period ended on said dates (subject, in the case of such financial statements as
at September 30, 2000, to normal year-end audit adjustments), all in accordance
with GAAP and practices applied on a consistent basis. The Company does not on
the date hereof have any material contingent liabilities, liabilities for taxes,
unusual forward or long-term commitments or unrealized or anticipated losses
from any unfavorable commitments, except as referred to or reflected or provided
for in said balance sheets or the notes thereto as at said dates. Since
September 30, 2000, there has been no material adverse change in the business,
operations or financial condition of the Company and its Subsidiaries, taken as
a whole, from that set forth in said financial statements as at said date.

         8.3. LITIGATION. Except as disclosed in SCHEDULE 8.3 hereto, (a) there
are no legal or arbitral proceedings, or any proceedings by or before any
governmental or regulatory authority or agency, now pending or (to the knowledge
of the Company) threatened against the Company, or any of its Subsidiaries that,
if adversely determined (i) could (either individually or in the aggregate) be
reasonably expected to (A) have a material adverse effect on the business,
condition (financial or otherwise), operations, performance, properties, or
prospects of the Company and its Subsidiaries, taken as a whole, other than the
litigation described in writing prior to July 1, 2000 (the "Pre-Disclosed
Litigation"); (B) adversely affect the ability of the Company or any Subsidiary
Guarantor to perform its obligations under the Loan Documents; or (C) adversely
affect the rights and remedies of the Administrative Agent and the Lenders under
the Loan Documents; or (ii) purports to adversely affect the credit facility
described herein; and (b) there shall have been no adverse change in the status,
or financial effect on the Company or any of its Subsidiaries, of the
Pre-Disclosed Litigation from that described in writing prior to July 1, 2000.

         8.4. NO BREACH. The execution and delivery of this Agreement and the
Notes and the other Loan Documents, the consummation of the transactions herein
and therein contemplated and the compliance with the terms and provisions hereof
and thereof do not and will not: (a) conflict with, violate or result in a
breach of, or require any consent under the charter or by-laws (or equivalent
constitutional documents) of any Obligor; (b) violate or result in a breach of
any applicable law or regulation; (c) conflict with, violate or result in a
breach of, or require any consent under any order, writ, injunction or decree of
any court or governmental authority or agency, or any agreement or instrument to
which the Company or any of its Subsidiaries is a party or by which any of them
or any of their Property is bound or to which any of them is subject; (d)
constitute a default, or result in the termination of any commitment to extend
credit, under any such agreement or instrument; or (e) result in the creation or


                                      - 42 -



imposition of any Lien upon any Property of the Company or any of its
Subsidiaries pursuant to the terms of any such agreement or instrument
(except for any Lien created by the Pledge Agreement); except to the extent,
with respect to the foregoing clauses (c) and (d), any such conflict,
violation, breach or default, or the failure to have any such consent, (i)
could not reasonably be expected (either individually or in the aggregate) to
have a Material Adverse Effect and (ii) does not and will not result in any
liability of the Administrative Agent or any Lender or in the acceleration or
required prepayment of any Indebtedness or the termination of any commitments
to extend credit.

         8.5. ACTION. Each Obligor has all necessary corporate or partnership
power, authority and legal right to execute, deliver and perform its obligations
under each of the Loan Documents to which it is a party; the execution, delivery
and performance by each Obligor of each of the Loan Documents to which it is a
party have been duly authorized by all necessary corporate or partnership action
on its part (including, without limitation, any required shareholder approvals);
and this Agreement has been duly and validly executed and delivered by each
Obligor and constitutes, and each of the Notes and the other Loan Documents to
which it is a party when executed and delivered by such Obligor (in the case of
the Notes, for value) will constitute, its legal, valid and binding obligation,
enforceable against each Obligor in accordance with its terms.

         8.6. APPROVALS. No authorizations, approvals or consents of, and no
filings or registrations with, any governmental or regulatory authority or
agency, or any securities exchange, are necessary for the execution, delivery or
performance by any Obligor of the Loan Documents to which it is a party or for
the legality, validity or enforceability hereof or thereof, except for
approvals, authorizations, consents, filings and registrations that have already
been obtained or made.

         8.7. USE OF CREDIT. None of the Obligors is engaged principally, or as
one of its important activities, in the business of extending credit for the
purpose, whether immediate, incidental or ultimate, of buying or carrying Margin
Stock, and no part of the proceeds of the Loans or other extensions of credit
hereunder will be used to buy or carry any Margin Stock.

         8.8. ERISA. Each Plan, and, to the knowledge of the Company, each
Multiemployer Plan, is in compliance in all material respects with, and has been
administered in all material respects in compliance with, the applicable
provisions of ERISA, the Code and any other Federal or State law, and no event
or condition has occurred and is continuing as to which the Company would be
under an obligation to furnish a report to the Lenders under Section 9.1(e)
hereof.

         8.9. TAXES. The Company and its Subsidiaries have filed all income tax
returns and all other material tax returns in all jurisdictions in which such
returns are required to have been filed by any of them and have paid all taxes
shown to be due and payable on such returns and all other taxes and assessments
in any material amount payable by any of them pursuant to any assessment
received by the Company or any of its Subsidiaries, except for any such taxes
and assessments (x) the amount, applicability or validity of which is currently
being contested in good faith by appropriate proceedings and (y) with respect to
which the Company or one of its Subsidiaries (as the case may be) has set aside
on its books adequate reserves in accordance with GAAP. The charges, accruals
and reserves on the books of the Company and its


                                       - 43 -



Subsidiaries in respect of taxes and other governmental charges are, in the
opinion of the Company, adequate. The Company has not given or been requested
to give a waiver of the statute of limitations relating to the payment of any
Federal, state, local and foreign taxes or other impositions in respect of
the Company or any of its Subsidiaries.

         8.10. INVESTMENT COMPANY ACT. None of the Obligors is an "investment
company", or a company "controlled" by an "investment company", within the
meaning of the Investment Company Act of 1940, as amended.

         8.11. PUBLIC UTILITY HOLDING COMPANY ACT. None of the Obligors is a
"holding company", or an "affiliate" of a "holding company" or a "subsidiary
company" of a "holding company", within the meaning of the Public Utility
Holding Company Act of 1935, as amended, or an "electric company," within the
meaning of Massachusetts General Laws, Chapter 164, as amended.

         8.12.    BORROWING AGREEMENTS AND LIENS.

                  (a) Part A of SCHEDULE 8.12 hereto includes a complete and
         correct list, as of the date hereof, of each credit agreement, loan
         agreement, indenture, purchase agreement, guarantee, letter of credit
         or other arrangement providing for or otherwise relating to any
         Indebtedness or any extension of credit (or commitment for any
         extension of credit) to, or guarantee by, the Company or any of its
         Subsidiaries the aggregate principal or stated amount of which equals
         or exceeds (or may equal or exceed) $1,000,000, and the aggregate
         principal or stated amount outstanding or that may become outstanding
         under each such arrangement is, as of the date hereof, correctly
         described in Part A of said SCHEDULE 8.12.

                  (b) Part B of SCHEDULE 8.12 hereto is a complete and correct
         list, as of the date hereof, of each Lien securing Indebtedness of any
         Person the aggregate principal or stated amount of which equals or
         exceeds (or may equal or exceed) $1,000,000 and covering any property
         of the Company or any of its Subsidiaries, and the aggregate
         Indebtedness secured (or that may be secured) by each such Lien and the
         property covered by each such Lien is, as of the date hereof, correctly
         described in said SCHEDULE 8.12.

         8.13. COMPLIANCE WITH LAWS INCLUDING ENVIRONMENTAL AND SAFETY MATTERS.
Each of the Company and its Subsidiaries is in compliance in all material
respects with all applicable federal, state, county and local statutes, laws,
rules, regulations, codes and ordinances and orders and directives including,
without limitation, all Environmental Laws, health and safety statutes and
regulations and specifically the Federal Food, Drug and Cosmetic Act, and the
regulations promulgated thereunder, the effect of the non-compliance with which
would have a Material Adverse Effect. To the knowledge of the Company, the
Company and its Subsidiaries are not subject to any material judicial or
administrative proceedings alleging the violation of any applicable law or
regulation and neither the Company or its Subsidiaries is the subject of any
federal, state or local investigation regarding, among other matters, the
Release of any Hazardous Material into the environment, the results of which
would reasonably be likely to materially and adversely affect the Company and
its Subsidiaries' financial condition, operations, business or prospects, taken
as a whole. Neither the Company or its Subsidiaries


                                       - 44 -



has any contingent liabilities in connection with any Release of any
Hazardous Material into the environment which would reasonably be likely to
materially and adversely affect the Company and its Subsidiaries' financial
condition, operations, businesses or prospects, taken as a whole.

         8.14. SUBSIDIARIES, ETC. Set forth on SCHEDULE 8.14 hereto is a list of
all of the Subsidiaries of the Company as of the date hereof complete and
correct in all material respects, together with, for each such Subsidiary, (i)
the jurisdiction of organization of such Subsidiary, (ii) each Person holding
ownership interests in such Subsidiary, (iii) the nature of the ownership
interests held by each such Person and the percentage of ownership of such
Subsidiary represented by such ownership interests, and (iv) a list of each
Subsidiary of the Borrower, the total assets of which, as of December 31, 1999,
equaled or exceeded three percent (3%) of the Consolidated total assets of the
Borrower and its Subsidiaries taken as a whole, together, for each such
Subsidiary, with an expression of the ratio, as of December 31, 1999, of the
total assets of such Subsidiary to the Consolidated total assets of the Company
and its Subsidiaries, each as reported in the books and records of the Company
and its Subsidiaries, and as calculated in accordance with GAAP. Except as
disclosed in SCHEDULE 8.14 hereto, (x) each of the Company and its Subsidiaries
owns, free and clear of Liens, and has the unencumbered right to vote, all
outstanding ownership interests in each Person shown to be held by it in
SCHEDULE 8.14 hereto, and (y) all of the issued and outstanding capital stock of
each such Person organized as a corporation is validly issued, fully paid and
nonassessable.

         8.15. TITLE TO ASSETS; ETC. The Company and its Subsidiaries own and
have on the date hereof good and marketable or merchantable title (subject only
to Liens permitted by Section 9.6 hereof) to the material Properties shown to be
owned in the audited financial statements referred to in Section 8.2 hereof
(other than properties disposed of in the ordinary course of business or
otherwise permitted to be disposed of pursuant to Section 9.5 hereof). The
Company and its Subsidiaries own and have on the date hereof good and marketable
or merchantable title to, or lease, and enjoy on the date hereof peaceful and
undisturbed possession of, all material Properties (subject only to Liens
permitted by Section 9.6 hereof) that are necessary for the operation and
conduct of its businesses.

         8.16. INTELLECTUAL PROPERTY RIGHTS. Except with respect to events or
matters which are not reasonably expected to have a Material Adverse Effect, (a)
the Company and its Subsidiaries own or license all material Intellectual
Property necessary for the conduct of its business as presently conducted; (b)
all material agreements pursuant to which the Company and its Subsidiaries
license the manufacture, marketing or sale of products employing its
Intellectual Property are in full force and effect; (c) no claims, demands,
suits, or proceedings are pending or, to the knowledge of the Company and its
Subsidiaries, threatened which impair their rights in any material Intellectual
Property used in the conduct of their business or any material agreement
relating thereto; and (d) the Company and its Subsidiaries have not infringed
(without any license therefor) any Intellectual Property of any other Person,
and the present conduct of the Company and its Subsidiaries' business does not
infringe any such rights in any way which would have a Material Adverse Effect.

         8.17. YEAR 2000 COMPLIANCE. The Company has taken all reasonably
necessary action to access and evaluate all of the hardware, software, embedded
microchips and other processing capabilities it uses and which is used in the
products it sells, directly or indirectly, and has made inquiry of the Company's
and its Subsidiaries' material suppliers and vendors, to


                                       - 45 -



be able to ensure that the Company and its Subsidiaries and each product they
sell will be able to function accurately and without interruption using date
information before, during and after January 1, 2000 sufficiently so as not
to cause a Material Adverse Effect. The Company and its Subsidiaries have
corrected, on or before September 30, 1999, all such problems that are
reasonably likely to have a Material Adverse Effect, and the cost of any
reprogramming and testing has not and is not reasonably likely to have a
Material Adverse Effect.

         8.18. TRUE AND COMPLETE DISCLOSURE. The reports, financial statements,
exhibits, schedules and other documents furnished by or on behalf of the
Obligors to the Administrative Agent or any Lender in connection with the
negotiation, preparation or delivery of this Agreement and the other Loan
Documents or included herein or therein or delivered pursuant hereto or thereto,
when taken as a whole do not contain any untrue statement of material fact or
omit to state any material fact necessary to make the statements herein or
therein, in light of the circumstances under which they were made, not
misleading. All written information furnished after the date hereof by the
Company and its Subsidiaries to the Administrative Agent and the Lenders in
connection with this Agreement and the other Loan Documents and the transactions
contemplated hereby and thereby will be true, complete and accurate in every
material respect, or (in the case of projections) based on reasonable estimates,
on the date as of which such information is stated or certified. There is no
fact known to the Company that could reasonably be expected to have a Material
Adverse Effect that has not been disclosed herein, in the other Loan Documents
or in a report, financial statement, exhibit, schedule, disclosure letter or
other writing furnished to the Lenders for use in connection with the
transactions contemplated hereby or thereby.

         8.19.    INITIAL ACQUISITION DISCLOSURE.

                  (a) As of the Closing Date, the Initial Acquisition Documents
         and the transactions contemplated thereunder have been duly executed,
         delivered, and performed in accordance with their terms by the
         respective parties thereto in all respects, including the fulfillment
         (not merely the waiver, except as may be disclosed to Administrative
         Agent and consented to in writing by the Administrative Agent) of all
         conditions precedent set forth therein and, giving effect to the terms
         of the Initial Acquisition Documents and the assignments to be executed
         and delivered thereunder, the Company acquired and has good and
         marketable title to the Purchased Initial Stock, free and clear of all
         claims, liens, pledges and encumbrances of any kind, except as
         permitted hereunder.

                  (b) As of the Closing Date, all actions and proceedings
         required by the Initial Acquisition Documents, applicable law or
         regulation (including, but not limited to, compliance with the
         Hart-Scott-Rodino Anti-Trust Improvements Act of 1976, as amended) have
         been taken and the transactions required thereunder shall have been
         duly and validly taken and consummated.

                  (c) As of the Closing Date, no court of competent jurisdiction
         has issued any injunction, restraining order or other order which
         prohibits consummation of the transactions described in the Initial
         Acquisition Documents and no governmental or other action or proceeding
         shall have been threatened or commenced, seeking any


                                      - 46 -



         injunction, restraining order, or other order which seeks to void or
         otherwise modify the transactions described in the Initial
         Acquisition Documents.

Section 9. COVENANTS OF THE COMPANY. The Company covenants and agrees with the
Lenders and the Agents that, so long as any Commitment, or Loan is outstanding
and until payment in full of all amounts payable by the Company hereunder:

         9.1. FINANCIAL STATEMENTS ETC.: The Company shall deliver to each of
the Lenders:

                  (a) as soon as available and in any event within the later of
         45 days after the end of the first three quarterly fiscal periods of
         each fiscal year of the Company or the deadline for the Company's Form
         10-Q filing for public record with the U.S. Securities and Exchange
         Commission, Consolidated statements of earnings, shareholders' equity
         and cash flows of the Company and its Subsidiaries for such period and
         for the period from the beginning of the respective fiscal year to the
         end of such period, and the related Consolidated balance sheets of the
         Company and its Subsidiaries as at the end of such period, setting
         forth in each case in comparative form, to the extent such figures
         appear therein, the corresponding Consolidated figures for the
         corresponding periods in the preceding fiscal year accompanied by a
         certificate of a senior financial officer of the Company, which
         certificate shall state that said Consolidated financial statements
         present fairly in all material respects the Consolidated financial
         position and results of operations of the Company and its Subsidiaries,
         in accordance with GAAP, consistently applied, as at the end of, and
         for, such period (subject to normal year-end audit adjustments);

                  (b) as soon as available and in any event within the later of
         90 days after the end of each fiscal year of the Company or the
         deadline for the Company's Form 10-K filing for public record with the
         U.S. Securities and Exchange Commission, Consolidated statements of
         earnings, shareholders' equity and cash flows of the Company and its
         Subsidiaries for such fiscal year and the related Consolidated balance
         sheets of the Company and its Subsidiaries as at the end of such fiscal
         year, setting forth in each case in comparative form, to the extent
         such figures appear therein, the corresponding Consolidated figures for
         the preceding fiscal year, and accompanied by a report thereon of
         independent certified public accountants of recognized national
         standing, which report shall state that said Consolidated financial
         statements present fairly in all material respects the Consolidated
         financial position and results of operations of the Company and its
         Subsidiaries as at the end of, and for, such fiscal year in accordance
         with GAAP, consistently applied;

                  (c) simultaneously with the delivery of the financial
         statements required under Section 9.1(a) and (b) above, (i) a copy of
         the Company's Form 10-Q or 10-K filing made for the periods covered by
         such financial statements or, if such filings are not available, a
         brief narrative description of material businesses and financial trends
         and developments and significant transactions that have occurred in the
         period or periods covered thereby, together with (ii) a Compliance
         Certificate as of the date of such financial statements, in the form
         attached as EXHIBIT D hereto;


                                      - 47 -



                  (d) promptly upon their becoming available, copies of all (i)
         regular, periodic and special reports that the Company shall have filed
         with the Securities and Exchange Commission (or any governmental agency
         substituted therefor) pursuant to the Securities Exchange Act of 1934,
         as amended (ii) financial statements, reports, notices or proxy or
         other statements sent to shareholders of the Company, (iii) business
         plans and financial statement forecasts, when and to the extent
         prepared and distributed to other creditors of the Company; and (iv)
         press releases and other statements generally made available by the
         Company to the public concerning material developments in the business
         of the Company;

                  (e) as soon as possible and in any event within five (5) days
         after any officer of Company obtains knowledge thereof: (i) Company's
         failure to make any required payment to any Plan in sufficient amount
         to comply with ERISA and the Code on or before the due date for such
         payment; (ii) the occurrence or expected occurrence of any "reportable
         event" under ERISA, "prohibited transaction" or "accumulated funding
         deficiency" with respect to any Plan; (iii) receipt by Company of any
         notice (A) from a Multiemployer Plan regarding the imposition of
         withdrawal liability; or (B) of the institution, or expectancy of the
         institution, of any proceeding or any other action which may result in
         the termination of any Plan, or Company's withdrawal or partial
         withdrawal from any Plan;

                  (f) promptly after the Company knows that any Default has
         occurred, a notice of such Default describing the same in reasonable
         detail and, together with such notice or as soon thereafter as
         possible, a description of the action that the Company has taken or
         proposes to take with respect thereto (a "Notice of Default");

                  (g) within thirty (30) days of obtaining knowledge thereof,
         the Company shall provide Lender with a written notice and reasonable
         description of any events or conditions which, if they existed and were
         known to the Company on the date of this Agreement, would have violated
         the warranty and representation made in Section 8.16 (dealing with
         Intellectual Property Rights);

                  (h) within sixty (60) days after the due date for delivery of
         the items under Sections 9.1(a) and 9.1(b) hereof, a listing of each
         Subsidiary of the Borrower, the total assets of which equaled or
         exceeded, as of the end of the period covered by such report, three
         percent (3%) of the Consolidated total assets of the Borrower and its
         Subsidiaries taken as a whole, together with, for each such Subsidiary,
         an expression of the ratio of the total assets of such Subsidiary to
         the Consolidated total assets of the Company and its Subsidiaries, each
         as reported in the books and records of the Company and its
         Subsidiaries and as calculated in accordance with GAAP;

                  (i) from time to time such other information regarding the
         Property, operations, business, financial condition or prospects of the
         Company or any of its Subsidiaries as any Lender or any Agent may
         reasonably request.

         9.2. LITIGATION. Promptly after the Company obtains knowledge thereof,
the Company will give notice to each Lender of all legal or arbitral
proceedings, and of all proceedings by or before any governmental or regulatory
authority or agency, and any material


                                      - 48 -



development in respect of such legal or other proceedings, affecting the Company
or any of its Subsidiaries, except proceedings that, if adversely determined,
would not (either individually or in the aggregate) reasonably be expected to
have a Material Adverse Effect.

         9.3.     EXISTENCE, ETC..  The Company:

                  (a) (i) will preserve and maintain its legal existence; (ii)
         will preserve and maintain and all of its material rights, privileges,
         licenses and franchises; and (iii) will cause each of its Material
         Subsidiaries to, preserve and maintain its legal existence and all of
         its material rights, privileges, licenses and franchises (PROVIDED that
         nothing in this Section 9.3 shall prohibit any transaction expressly
         permitted under Section 9.5 hereof);

                  (b) will, and will cause each of its Subsidiaries to, comply
         with the requirements of all applicable laws, rules, regulations and
         orders of governmental or regulatory authorities if failure to comply
         with such requirements could reasonably be expected (either
         individually or in the aggregate) to have a Material Adverse Effect;

                  (c) will, and will cause each of its Subsidiaries to, pay and
         discharge all taxes, assessments and governmental charges or levies
         imposed on it or on its income or profits or on any of its Property
         prior to the date on which penalties attach thereto, except for any
         such tax, assessment, charge or levy the payment of which is being
         contested in good faith and by proper proceedings and against which
         adequate reserves are being maintained in accordance with GAAP
         consistently applied, and except for any such tax, assessment, charge
         or levy the failure to pay which would not have a Material Adverse
         Effect;

                  (d) will, and will cause each Obligor to, maintain all of its
         Properties used or useful in its business in good working order and
         condition, ordinary wear and tear excepted;

                  (e) will, and will cause each of its Subsidiaries to, keep
         adequate records and books of account, in which complete entries will
         be made in accordance with GAAP consistently applied; and

                  (f) will, and will cause each of its Material Subsidiaries to,
         permit representatives of any Lender or any Agent, upon reasonable
         advance notice to the Company or such Material Subsidiary and during
         normal business hours, to examine, copy and make extracts from its
         books and records, to inspect any of its Properties, and to discuss its
         business and affairs with its officers, all to the extent reasonably
         requested by such Lender or the Administrative Agent (as the case may
         be); PROVIDED THAT (i) the Agents and the Lenders will endeavor to
         cooperate with the Company or such Material Subsidiary in order to
         minimize any interference with its normal business operations that may
         result from any such inspection and (ii) except as otherwise provided
         in Section 12.3 hereof, all expenses of the Agents and the Lenders in
         connection with the exercise of their rights under this Section 9.3(f)
         shall be for their own account.

         9.4. INSURANCE. The Company will, and will cause each of its
Subsidiaries to, maintain insurance with financially sound and reputable
insurance companies, and with respect


                                      - 49 -



to Property and risks of a character usually maintained by corporations engaged
in the same or similar business similarly situated, against loss, damage and
liability of the kinds and in the amounts customarily maintained by such
corporations.

         9.5.     PROHIBITION OF FUNDAMENTAL CHANGES.

                  (a) MERGER, CONSOLIDATION, ETC. The Company will not, nor will
         it permit any of its Subsidiaries to, enter into any transaction of
         merger or consolidation or amalgamation, or liquidate, wind up or
         dissolve itself (or suffer any liquidation or dissolution).

                  (b) ACQUISITIONS. The Company will not, nor will it permit any
         of its Subsidiaries to, acquire any business or Property from, or
         capital stock of, or be a party to any acquisition of, any Person.

                  (c) SALE OF ASSETS. The Company will not, nor will it permit
         any of its Subsidiaries to, convey, sell, lease, transfer or otherwise
         dispose of, in one transaction or a series of transactions, any part of
         its business or Property, whether now owned or hereafter acquired
         (including, without limitation, receivables and leasehold interests)
         other than the sale of inventory in the course of business.

                  (d) EXCEPTIONS. Notwithstanding the foregoing provisions of
         this Section 9.5 (provided, however, that nothing in the following
         clauses shall permit the Company to effect a transaction, disposition,
         or transfer that is prohibited by the Pledge Agreement):

                                    (i) any Subsidiary of the Company may be
                  merged or consolidated with or into, or have its assets
                  liquidated and distributed to, the Company or any other
                  Subsidiary of the Company; PROVIDED that (x) if any such
                  merger or consolidation shall be with the Company, the Company
                  shall be the Person surviving such merger or consolidation,
                  (y) if any such merger or consolidation shall be between any
                  Subsidiary of the Company and a Wholly Owned Subsidiary of the
                  Company, such Wholly Owned Subsidiary shall be the Person
                  surviving such merger or consolidation, (z) if any such merger
                  or consolidation shall be between a Subsidiary Guarantor and a
                  Subsidiary of the Company that is not a Subsidiary Guarantor
                  (other than Genzyme Securities Corporation), and such
                  Subsidiary Guarantor is not the continuing or surviving
                  Person, then the continuing or surviving Person shall have
                  assumed all of the obligations of such Subsidiary Guarantor
                  hereunder and under the other Loan Documents and (aa) if any
                  such merger or consolidation shall be between Genzyme
                  Securities Corporation and a Subsidiary of the Company that is
                  not a Subsidiary Guarantor, and Genzyme Securities Corporation
                  is not the continuing or surviving Person, then the Company
                  and its Subsidiaries shall, or shall cause the holder of the
                  stock in such continuing or surviving Person, to execute and
                  deliver a Pledge Agreement in substantially the form of
                  EXHIBIT G, together with the certificates for all shares of
                  capital stock of the continuing or surviving Person pledged
                  thereunder and undated stock powers;

                                       - 50 -


                                    (ii) the Company and its Subsidiaries may
                  acquire any assets used or useful in the lines of business
                  permitted under Section 9.10 or the stock or other equity
                  interests or rights as a holder of indebtedness of any Person
                  that is engaged in a line of business permitted to the Company
                  under Section 9.10 or merge any Person that is in a line or
                  lines of business permitted under Section 9.10 with the
                  Company or a Subsidiary or the Company or a Subsidiary with
                  any such Person (provided that the conditions in the provisos
                  in Section 9.5(d)(i) are satisfied with respect to such
                  merger) provided that at the time of the consummation of any
                  such transaction and after giving effect thereto, the Company
                  shall be in compliance with the covenants in Section 9.9 as of
                  the end of the most recent fiscal quarter or annual period of
                  the Company and the transaction will not be reasonably likely
                  to result in the noncompliance with such financial covenants;

                                    (iii) the Company or any of its Subsidiaries
                  may purchase inventory and other Property to be sold or used
                  in the ordinary course of business, make Investments permitted
                  by Section 9.8 hereof and make Capital Expenditures in the
                  ordinary course of its business;

                                    (iv) the Company or any Subsidiary of the
                  Company may convey, sell, lease, loan, transfer or otherwise
                  dispose of any or all of its Property to the Company or any
                  other Subsidiary of the Company (and the Company or such other
                  Subsidiary may acquire such Property); PROVIDED that if any
                  such conveyance, sale, lease, loan, transfer or other
                  disposition is to a Subsidiary (other than Genzyme Securities
                  Corporation) that is not a Subsidiary Guarantor and relates to
                  all or any material part of the Property of the Company or a
                  Subsidiary Guarantor, then the Company shall cause such
                  transferee Subsidiary to assume, and such transferee
                  Subsidiary shall assume, all of the obligations of the Company
                  or such Subsidiary Guarantor hereunder and under the other
                  Loan Documents; and PROVIDED, further, that the Company or
                  such Subsidiary Guarantor shall remain fully obligated as an
                  Obligor hereunder;

                                    (v) the Company or any Subsidiary may
                  convey, sell, lease, transfer or otherwise dispose of any
                  non-material Property (of the Company and its Subsidiaries,
                  taken as a whole) including equity interests in any Person and
                  the licensing of patents and product rights; and

                                    (vi) the Company or any Subsidiary may
                  lease or sublease any of its real Property.

         9.6. LIMITATION ON LIENS. The Company will not, nor will it permit any
of its Subsidiaries to, create, incur, assume or suffer to exist any Lien upon
any of its Property, whether now owned or hereafter acquired, except:

                  (a) Liens in existence on the date hereof, including, without
         limitation, Liens required to be listed on SCHEDULE 8.12 (parts A and
         B) hereto (excluding, however, Liens securing Indebtedness to be repaid
         with the proceeds of Loans hereunder, as


                                      -51-


         indicated on said SCHEDULE 8.12 (parts A and B), from and after the
         date of such repayment);

                  (b) Liens imposed by any governmental authority for taxes,
         assessments or charges not in excess of $1,000,000 or not yet due or
         that are being contested in good faith and by appropriate proceedings
         if adequate reserves with respect thereto are maintained on the books
         of the Company or the affected Subsidiaries, as the case may be, in
         accordance with GAAP;

                  (c) carriers', warehousemen's, mechanics', materialmen's,
         repairmen's or other like Liens arising in the ordinary course of
         business that are not overdue or that are being contested in good faith
         and by appropriate proceedings if adequate reserves with respect
         thereto are maintained or the books of the Company or the affected
         Subsidiaries, as the case may be, in accordance with GAAP;

                  (d) pledges or deposits under worker's compensation,
         unemployment insurance and other social security legislation;

                  (e) (i) deposits to secure the performance of bids, trade
         contracts (other than for Indebtedness), leases, statutory obligations,
         surety and appeal bonds, performance bonds and other obligations of a
         like nature incurred in the ordinary course of business and (ii) Liens
         arising from a seller's title retention provisions with respect to
         goods or services acquired in the ordinary course of business;

                  (f) easements, rights-of-way, restrictions and other similar
         encumbrances incurred in the ordinary course of business and
         encumbrances consisting of zoning restrictions, easements, licenses,
         restrictions on the use of Property or imperfections in title thereto
         that, in the aggregate, are not material in amount, and that do not in
         any case materially detract from the value of the Property subject
         thereto or interfere with the ordinary conduct of the business of the
         Company or any of its Subsidiaries;

                  (g) Liens on Property of any Person that becomes a Subsidiary
         of the Company after the date hereof, PROVIDED that such Liens are in
         existence at the time such Person becomes a Subsidiary of the Company
         and were not created in anticipation thereof;

                  (h) Liens upon fixed or capital assets to secure Purchase
         Money Indebtedness or Capital Lease Obligations of the Company or a
         Subsidiary; PROVIDED, THAT, (i) such Lien does not extend to or cover
         any other Property of the Company or such Subsidiary and (ii) such Lien
         does not secure any Indebtedness other than the Indebtedness so
         incurred;

                  (i)      Intentionally omitted;

                  (j) Liens on the Genzyme (UK) Limited manufacturing facility
         and equipment securing the repayment of the Indebtedness permitted
         under Section 9.7(i);

                  (k) Liens arising from or upon any judgment or award, provided
         that such judgment or award is being contested in good faith by proper
         appeal proceedings, such


                                       -52-


         judgment or award is not secured by any Lien which is not discharged
         within thirty (30) days, and only so long as execution thereon shall
         be stayed;

                  (l) Liens securing Indebtedness otherwise permitted under
         Section 9.7 (other than Subordinated Debt) that does not exceed, in the
         aggregate, $1,000,000 at any one time outstanding; and

                  (m) Liens now or hereafter granted to the Agents or Lenders
         under the Loan Documents.

         9.7. INDEBTEDNESS. The Company will not, nor will it permit any of its
Subsidiaries to, create, incur, assume, or suffer to exist any Indebtedness
except:

                  (a) Indebtedness to the Lenders hereunder and under the other
         Loan Documents;

                  (b) Indebtedness outstanding on the date hereof including
         Indebtedness in excess of $1,000,000 that is required to be listed on
         SCHEDULE 8.12 hereto (excluding however, the Indebtedness to be repaid
         with the proceeds of Loans hereunder, as indicated on said SCHEDULE
         8.12, from and after the date of such repayment);

                  (c) Indebtedness of (i) Subsidiaries of the Company to the
         Company, (ii) the Company to any of its Subsidiaries or (iii) of
         Subsidiaries to Subsidiaries, PROVIDED, HOWEVER, that any Indebtedness
         of the Company to any of its Subsidiaries (other than the Subsidiary
         Guarantors and Genzyme Securities Corporation), and any Indebtedness of
         any Subsidiary Guarantor or Genzyme Securities Corporation to any of
         the Company's other Subsidiaries (other than the Subsidiary Guarantors
         and Genzyme Securities Corporation), shall be subject to a
         subordination agreement unconditionally providing that: (x) such
         Indebtedness is subordinate and subject in right of payment to the
         prior payment in full of the Obligations; (y) that no payments shall be
         made on such Indebtedness, nor shall the holder of such Indebtedness
         exercise any right or remedy with respect to such Indebtedness, until
         payment and satisfaction in full of the Obligations; and (z)
         notwithstanding clauses (x) and (y), payments may be made on account of
         such Indebtedness UNLESS there has occurred an Event of Default that is
         continuing or such payment(s) would result in an Event of Default;

                  (d) Indebtedness constituting Purchase Money Indebtedness or
         Capital Lease Obligations incurred in the ordinary course of Company's
         or such Subsidiaries' business;

                  (e) Indebtedness under or in respect of currency exchange
         contracts or interest rate protection obligations incurred in the
         ordinary course of business;

                  (f) Indebtedness in connection with performance bonds or
         letters of credit obtained and issued in the ordinary course of
         business, including letters of credit related to insurance associated
         with claims for work-related injuries;

                  (g) Subordinated Debt;


                                      -53-




                  (h) Indebtedness incurred to renew, extend, refinance or
         refund any Indebtedness expressly permitted by any of the clauses of
         this Section 9.7; and

                  (i) additional Indebtedness of the Company and its
         Subsidiaries, including Indebtedness incurred to finance the
         construction of manufacturing facilities and the acquisition of the
         equipment for Genzyme (UK) Limited, up to but not exceeding ten percent
         (10%) of the book value of the Consolidated Tangible Assets, calculated
         in accordance with GAAP (in determining whether additional Indebtedness
         exceeds the ten percent (10%) maximum under this Section 9.7(i), any
         Indebtedness of the Company or any Subsidiary that is Guaranteed by the
         Company or any Subsidiary, collectively with the Indebtedness
         consisting of any Guarantee of such Subsidiary's or Company's
         Indebtedness, shall together be deemed a single item of Indebtedness
         (in the amount of the primary obligor's Indebtedness)).

         9.8. INVESTMENTS. The Company will not, nor will it permit any of its
Subsidiaries to, make or permit to remain outstanding any Investments except
Investments made in the ordinary course of business of the Company or its
Subsidiaries or that would be permitted under the terms of Section 9.5.

         9.9. FINANCIAL COVENANTS.

                  (a) CONSOLIDATED QUICK RATIO. The Company will not permit the
         Consolidated Quick Ratio on the last day of any fiscal quarter of the
         Company to be less than 1.50 to 1.00 (commencing with the fiscal
         quarter of the Company ending in June, 2000).

                  (b) CONSOLIDATED FIXED CHARGE COVERAGE RATIO. The Company will
         not permit the Consolidated Fixed Charge Coverage Ratio for any period
         of four consecutive fiscal quarters of the Company (commencing with the
         period of four consecutive fiscal quarters of the Company ending in
         June, 2000) to be less than 3.00 to 1.00.

                  (c) CONSOLIDATED LEVERAGE RATIO. The Company will not permit,
         as of the last day of any fiscal quarter (commencing with the fiscal
         quarter of the Company ending in June, 2000), the ratio of (a)
         Consolidated Funded Debt less all Unrestricted Cash and Marketable
         Investments of the Company and its Consolidated Subsidiaries in excess
         of $125,000,000; to (b) Consolidated EBITDA of the Company for the
         period of four consecutive fiscal quarters then ended to exceed 2.00 to
         1.00.

         9.10. LINES OF BUSINESS. The Company will not, and will not permit any
of its Subsidiaries to, engage to any significant extent in any line or lines of
business activity other than the biotechnology, pharmaceutical, medical devices,
therapeutic products, medical products, and medical services and diagnostic
services businesses.

         9.11. USE OF PROCEEDS. The Company will use the proceeds of the Loans
hereunder to finance transactions permitted under Section 9.5 and to finance the
ongoing working capital and other general corporate needs of the Company and its
Subsidiaries (in each case, in compliance with all applicable legal and
regulatory requirements, including, without limitation, Regulations U and X and
the Securities Act of 1933 and the Securities Exchange Act



                                      -54-



of 1934); PROVIDED that neither any Agent nor any Lender shall have any
responsibility as to the use of any of such proceeds.

         9.12. CERTAIN OBLIGATIONS RESPECTING COMPANY AND SUBSIDIARIES.

                  (a) Except as permitted under Section 9.5 hereof, the Company
         will, and will cause each of its Subsidiaries to, take such action from
         time to time as shall be necessary to ensure that the Company and each
         of its Subsidiaries at all times collectively own (subject to no Lien
         other than the Lien granted under the Pledge Agreement) at least the
         same percentage of the issued and outstanding shares of each class of
         stock or other equity ownership interests of each of its Subsidiaries
         as is collectively owned by the Company and its Subsidiaries on the
         Closing Date.

                  (b) The Company will not, and will not permit any of its
         Material Subsidiaries to, enter into, after the Closing Date, any
         indenture, agreement, instrument or other arrangement (other than
         entering into one or more of the Loan Documents) that, directly or
         indirectly, prohibits or restrains, or has the effect of prohibiting or
         restraining, or imposes materially adverse conditions upon, the
         incurrence or payment of Indebtedness, the granting of Liens, the
         declaration or payment of dividends, the making of loans, advances or
         other Investments or the sale, assignment, transfer or other
         disposition of Property, other than (i) any indenture, agreement,
         instrument or other arrangement relating to Indebtedness of a
         Subsidiary of the Company acquired by the Company after the date hereof
         which was entered into by such Subsidiary prior to the date on which
         the Company acquired such Subsidiary (and which was not entered into in
         contemplation of such acquisition), provided that the terms and
         conditions thereof only relate to such Subsidiary and not the Company
         or its other Subsidiaries and are no more restrictive than the terms
         and conditions hereof, (ii) any indenture, agreement, instrument or
         other arrangement effecting the refinancing of any Indebtedness
         referred to in clause (i) above so long as the prohibitions and
         restrictions contained in the documents relating to such refinancing
         are as a whole no less favorable to the Lenders or the obligor in
         respect of such Indebtedness than the prohibitions and restrictions
         contained in the documents relating to the Indebtedness being
         refinanced, (iii) customary non-assignment provisions in leases
         governing leasehold interests to the extent such provisions restrict
         transfer of rights under the related lease, (iv) restrictions on the
         transfer of or the granting of Liens on Property of the Company or any
         of its Subsidiaries subject to a Lien expressly permitted by Section
         9.6 hereof securing Indebtedness expressly permitted by Section 9.7
         hereof to the extent such restrictions are contained in documents
         evidencing or relating to such Indebtedness and (v) restrictions on the
         transfer of Property of the Company or any of its Subsidiaries that is
         the subject of a disposition expressly permitted by Section 9.5 hereof
         to the extent such restrictions are contained in the documents relating
         to such disposition.

         9.13. ADDITIONAL SUBSIDIARY GUARANTORS. In the event that the Company
shall, after the date of this Agreement, hold or acquire any Material Subsidiary
that is not already a Subsidiary Guarantor, the Company will, and will cause
each of its other Subsidiaries to, immediately cause such Material Subsidiary
(a) to execute and deliver to each Agent and each Lender a joinder agreement in
the form of EXHIBIT E hereto, and (b) to deliver such proof of corporate action,
incumbency of officers, opinions of counsel (it being agreed that any such



                                      -55-




opinion may be an opinion of internal counsel qualified to practice law in
the jurisdiction(s) relevant to such opinion) and other documents as are
consistent with those delivered by the Company pursuant to Section 7.1 hereof
or as the Administrative Agent shall have reasonably requested. Upon
execution and delivery by such Material Subsidiary of any agreement referred
to in the foregoing clauses, each of the representations and warranties in
Section 8 hereof with respect to such Material Subsidiary and each Loan
Document to which it shall have become a party shall be deemed made by the
Company.

         9.14. SUBORDINATED DEBT. The Company shall not, and shall cause its
Subsidiaries to not, make any prepayments of principal, any non-mandatory
payments of principal, or any other payments of principal other than regularly
scheduled payments of principal on account of Subordinated Debt, other than by
conversion to Capital Stock or other equity of the Company or other Subordinated
Debt.

Section 10. EVENTS OF DEFAULT. If one or more of the following events (herein
called "EVENTS OF DEFAULT") shall occur and be continuing:

                  (a) The Company shall default in the payment when due (whether
         at stated maturity or upon mandatory or optional prepayment) of any
         principal of or interest on any Loan, provided, however, that as to the
         non-payment of interest, there shall be a one (1) Business Day grace
         period without any requirement of notice, but the Company shall not be
         entitled to such grace period more than once in any consecutive
         twelve-month period; or

                  (b) The Company shall default in the payment of any fee or any
         other amount (other than principal of or interest on any Loan) payable
         by it hereunder or under any other Loan Document and such default shall
         continue unremedied for a period of five (5) days after notice to the
         Company from the Administrative Agent; or

                  (c) The Company or any of its Subsidiaries shall default in
         the payment when due of any principal of or interest on any of its
         other Indebtedness aggregating to at least $5,000,000 (after the
         expiration of any grace period originally provided for); or any event
         specified in any note, agreement, indenture or other document
         evidencing or relating to any such Indebtedness shall occur if the
         effect of such event is to cause, or (with the giving of any notice or
         the lapse of time or both) to permit the holder or holders of such
         Indebtedness (or a trustee or agent on behalf of such holder or
         holders) to cause, such Indebtedness to become due, or to be prepaid in
         full (whether by redemption, purchase, offer to purchase or otherwise),
         prior to its stated maturity; or

                  (d) Any representation, warranty or certification made or
         deemed made herein or in any other Loan Document (or in any
         modification or supplement hereto or thereto) by any Obligor, or any
         certificate furnished to any Lender or any Agent pursuant to the
         provisions hereof or thereof, shall prove to have been false or
         misleading as of the time made or furnished in any material respect; or

                  (e) (i) The Company shall default in the performance of any of
         its obligations under any of Sections 9.1(c), 9.1 (e), 9.1(f), 9.1(g),
         9.3(a)(i), 9.3(f), 9.5, 9.6, 9.7, 9.9, 9.10, 9.11, 9.12, 9.13, and 9.14
         hereof; or



                                      -56-




                              (ii)  The Company shall default in the performance
         of any of its obligations under any of Sections 9.1(a), 9.1(b), or
         9.1(h) hereof, provided, however, that as to these sections, there
         shall be a ten (10) Business Day grace period without any requirement
         of notice, but the Company shall not be entitled to such grace period
         more than once in any consecutive twelve-month period; or

                              (iii) The Company shall default in the performance
         of any of its obligations under Section 9.2 hereof, provided, however,
         that as to this section, there shall be a thirty (30) day grace period
         without any requirement of notice; or

                               (iv)   Any Obligor shall default in the
         performance of any of its other obligations in this Agreement or any
         other Loan Document and such default (if remediable) shall continue
         unremedied for a period of 30 or more days after notice thereof to the
         Company by the Administrative Agent or any Lender (through the
         Administrative Agent); or

                  (f) The Company or any of its Material Subsidiaries shall
         admit in writing its inability to, or be generally unable to, pay its
         debts as such debts become due; or

                  (g) The Company or any of its Material Subsidiaries shall (i)
         apply for or consent to the appointment of, or the taking of possession
         by, a receiver, custodian, trustee, examiner or liquidator of itself or
         of all or a substantial part of its Property, (ii) make a general
         assignment for the benefit of its creditors, (iii) commence a voluntary
         case under the Bankruptcy Code, (iv) file a petition seeking to take
         advantage of any other law relating to bankruptcy, insolvency,
         reorganization, liquidation, dissolution, arrangement or winding-up, or
         composition or readjustment of debts, (v) fail to convert in a timely
         and appropriate manner, or acquiesce in writing to, any petition filed
         against it in an involuntary case under the Bankruptcy Code, (vi) cause
         or be subject to any event with respect to it which, under the
         applicable laws of any foreign jurisdiction, has an analogous effect to
         any of the events specified in the foregoing clauses (i) to (v) or
         (vii) take any corporate action for the purpose of effecting any of the
         foregoing; or

                  (h) A proceeding or case shall be commenced, without the
         application or consent of the Company or any of its Material
         Subsidiaries, in any court of competent jurisdiction, seeking (i) its
         reorganization, liquidation, dissolution, arrangement or winding-up, or
         the composition or readjustment of its debts, (ii) the appointment of a
         receiver, custodian, trustee, examiner, liquidator or the like of the
         Company or such Material Subsidiary or of all or any substantial part
         of its Property, (iii) similar relief in respect of the Company or such
         Material Subsidiary under any law relating to bankruptcy, insolvency,
         reorganization, winding-up, or composition or adjustment of debts, and
         such proceeding or case shall continue undismissed, or an order,
         judgment or decree approving or ordering any of the foregoing shall be
         entered and continue unstayed and in effect, for a period of 60 or more
         days or (iv) relief with respect to it which, under the applicable laws
         of any foreign jurisdiction, has an analogous effect to any of the
         actions specified in foregoing clauses (i) to (iii); or an order for
         relief against the Company or such Material Subsidiary shall be entered
         in an involuntary case under the Bankruptcy Code; or



                                      -57-


                  (i) A final judgment or judgments for the payment of money in
         excess of $1,000,000 in the aggregate, or imposing injunctive or other
         equitable relief which would have a Material Adverse Effect (exclusive
         of judgment amounts fully covered by insurance where the insurer has a
         claims paying ability rated AA- or better from S&P or a financial
         strength rating of AA or better from Moody's) shall be rendered by one
         or more courts, administrative tribunals or other bodies having
         jurisdiction against the Company or any of its Subsidiaries and the
         same shall not be discharged (or provision shall not be made for such
         discharge) or vacated, or a stay of execution thereof shall not be
         procured, within 30 days from the date of entry thereof and the Company
         or the relevant Subsidiary shall not, within said period of 30 days, or
         such longer period during which execution of the same shall have been
         stayed, appeal therefrom and cause the execution thereof to be stayed
         during such appeal; or

                  (j) An event or condition specified in Section 9.1(e) hereof
         shall occur or exist with respect to any Plan or Multiemployer Plan
         and, as a result of such event or condition, together with all other
         such events or conditions, the Company or any ERISA Affiliate shall
         incur or in the opinion of the Required Lenders shall be reasonably
         likely to incur a liability to a Plan, a Multiemployer Plan or the PBGC
         (or any combination of the foregoing) that, in the determination of the
         Required Lenders, would (either individually or in the aggregate) have
         a Material Adverse Effect; or

                  (k) There shall have been asserted against the Company or any
         of its Subsidiaries an Environmental Claim that, in the judgment of the
         Required Lenders is reasonably likely to be determined adversely to the
         Company or any of its Subsidiaries, and the amount thereof (either
         individually or in the aggregate) is reasonably likely to have a
         Material Adverse Effect (insofar as such amount is payable by the
         Company or any of its Subsidiaries but after deducting any portion
         thereof that is reasonably expected to be paid by other creditworthy
         Persons jointly and severally liable therefor);

                  (l) Any Fundamental Change shall occur; or

                  (m) The Administrative Agent shall cease to have a perfected,
         first-priority security interest in the stock of Genzyme Securities
         Corporation (unless it holds a perfected, first-priority security
         interest in the surviving entity under the terms of Section 9.5(d)(i)
         hereof);

THEREUPON: (1) in the case of an Event of Default other than one referred to in
clause (g) or (h) of this Section 10 with respect to any Obligor, upon request
of the Required Lenders, (A) the Administrative Agent shall, by notice to the
Company, terminate the Commitments and they shall thereupon terminate, and (B)
the Administrative Agent shall, by notice to the Company declare the principal
amount then outstanding of, and the accrued interest on, the Loans and all other
amounts payable by the Obligors hereunder and under the Notes (including,
without limitation, any amounts payable under Section 5.5 hereof) to be
forthwith due and payable, whereupon such amounts shall be immediately due and
payable without presentment, demand, protest or other formalities of any kind,
all of which are hereby expressly waived by each Obligor; and (2) in the case of
the occurrence of an Event of Default referred to in clause (g) or (h) of this
Section 10 with respect to any Obligor, the Commitments shall automatically be
terminated and the principal amount then outstanding of, and the accrued
interest on, the Loans



                                      -58-



and all other amounts payable by the Obligors hereunder and under the Notes
(including, without limitation, any amounts payable under Section 5.5 hereof)
shall automatically become immediately due and payable without presentment,
demand, protest or other formalities of any kind, all of which are hereby
expressly waived by each Obligor.

Section 11.    THE AGENTS

         11.1. APPOINTMENT, POWERS AND IMMUNITIES. Each Lender hereby appoints
and authorizes the Administrative Agent to act as its agent hereunder and under
the other Loan Documents with such powers as are specifically delegated to the
Administrative Agent by the terms of this Agreement and of the other Loan
Documents, together with such other powers as are reasonably incidental thereto.
Each Agent (which term as used in this sentence and in Section 11.5 and the
first sentence of Section 11.6 hereof shall include reference to their
respective affiliates and their own and their affiliates' officers, directors,
employees and agents):

                  (a) shall have no duties or responsibilities except those
         expressly set forth in this Agreement and in the other Loan Documents,
         and shall not by reason of this Agreement or any other Loan Document be
         a trustee for any Lender;

                  (b) shall not be responsible to the Lenders for any recitals,
         statements, presentations or warranties contained in this Agreement or
         in any other Loan Document, or in any certificate or other document
         referred to or provided for in, or received by any of them under, this
         Agreement or any other Loan Document, or for the value, validity,
         effectiveness, genuineness, enforceability or sufficiency of this
         Agreement, any Note or any other Loan Document or any other document
         referred to or provided for herein or therein or for any failure by the
         Company or any other Person to perform any of its obligations hereunder
         or thereunder;

                  (c) shall not, except to the extent expressly instructed by
         the Required Lenders, be required to initiate or conduct any litigation
         or collection proceedings hereunder or under any other Loan Document;
         and

                  (d) shall not be responsible for any action taken or omitted
         to be taken by it hereunder or under any other Loan Document or under
         any other document or instrument referred to or provided for herein or
         therein or in connection herewith or therewith, except for its own
         gross negligence, bad faith or willful misconduct.

Each Agent may employ agents and attorneys-in-fact and shall not be responsible
for the negligence or misconduct of any such agents or attorneys-in-fact
selected by it in good faith. Each Agent may deem and treat the payee of a Note
as the holder thereof for all purposes hereof unless and until a notice of the
assignment or transfer thereof shall have been filed with the Administrative
Agent, together with the consent of the Company to such assignment or transfer
(to the extent provided in Section 12.7(b) hereof). The identification of ABN
AMRO as Syndication Agent and the identification of First Union as Documentation
Agent hereunder shall not create any rights in favor of such parties in such
capacities, nor subject them to any duties or obligations, in such capacity.



                                      -59-



         11.2. RELIANCE BY AGENTS. Each Agent shall be entitled to rely upon any
certification, notice or other communication (including, without limitation, any
thereof by telephone, telecopy, telegram or cable) believed by it to be genuine
and correct and to have been signed or sent by or on behalf of the proper Person
or Persons, and upon advice and statements of legal counsel, independent
accountants and other experts selected by such Agent. As to any matters not
expressly provided for by this Agreement or any other Loan Document, each Agent
shall in all cases be fully protected in acting, or in refraining from acting,
hereunder or thereunder in accordance with instructions given by the Required
Lenders or, if provided herein, in accordance with the instructions given by all
of the Lenders as is required in such circumstance, and such instructions of
such Lenders and any action taken or failure to act pursuant thereto shall be
binding on all of the Lenders.

         11.3. DEFAULTS. Except with respect to Events of Default consisting of
the failure to make regularly scheduled interest payments hereunder, the failure
to repay all 364-Day Facility Revolving Credit Loans on the 364-Day Facility
Revolving Credit Commitment Termination Date, or the failure to pay all
Three-Year Facility Revolving Credit Loans on the Three-Year Facility Revolving
Credit Commitment Termination Date, no Agent shall be deemed to have knowledge
or notice of the occurrence of a Default unless the Administrative Agent has
received notice from a Lender or the Company specifying such Default and stating
that such notice is a "Notice of Default". In the event that the Administrative
Agent receives such a notice of the occurrence of a Default, the Administrative
Agent shall give prompt notice thereof to the other Agents and the Lenders. The
Administrative Agent shall (subject to Sections 11.1 and 11.7 hereof) take such
action with respect to such Default as shall be directed by the Required
Lenders, PROVIDED that, unless and until the Administrative Agent shall have
received such directions, the Administrative Agent may but shall not be
obligated to take such action, or refrain from taking such action, with respect
to such Default as it shall deem advisable in the best interest of the other
Agents and the Lenders except to the extent that this Agreement expressly
requires that such action be taken, or not be taken, only with the consent or
upon the authorization of the Required Lenders or all of the Lenders.

         11.4. RIGHTS AS A LENDER. With respect to its Commitments and the Loans
made by it, Fleet (and any successor acting as Administrative Agent) and ABN
AMRO (and any successor acting as Syndication Agent) and First Union (and any
successor acting as Documentation Agent) in their capacity as a Lender hereunder
shall have the same rights and powers hereunder as any other Lender and may
exercise the same as though it were not acting as an Agent, and the term
"Lender" or "Lenders" shall, unless the context otherwise indicates, include any
such Agent in its individual capacity. Fleet (and any successor acting as
Administrative Agent) and ABN AMRO (and any successor acting as Syndication
Agent) and First Union (and any successor acting as Documentation Agent) and
their respective affiliates may (without having to account therefor to any
Lender) accept deposits from, lend money to, make investments in and generally
engage in any kind of banking, trust or other business with the Obligors (and
any of their Subsidiaries or Affiliates) as if they were not acting as an Agent,
and Fleet (and any such successor) and ABN AMRO (and any such successor) and
First Union (and any such successor) and their respective affiliates may accept
fees and other consideration from the Obligors for services in connection with
this Agreement or otherwise without having to account for the same to the
Lenders.



                                      -60-



         11.5. INDEMNIFICATION. The Lenders agree to indemnify each of the
Agents (to the extent not reimbursed under Section 12.3 hereof, but without
limiting the obligations of the Company under said Section 12.3) ratably in
accordance with their respective Commitments, for any and all liabilities,
obligations, losses, damages, penalties, actions, judgments, suits, costs,
expenses or disbursements of any kind and nature whatsoever that may be
imposed on, incurred by or asserted against any Agent (including by any
Lender) arising out of or by reason of any investigation in or in any way
relating to or arising out of this Agreement or any other Loan Document or
any other documents contemplated by or referred to herein or therein or the
transactions contemplated hereby or thereby (including, without limitation,
the costs and expenses that the Company is obligated to pay under Section
12.3 hereof, but excluding, unless a Default has occurred and is continuing,
normal administrative costs and expenses incident to the performance of its
agency duties hereunder) or the enforcement of any of the terms hereof or
thereof or of any such other documents, PROVIDED that no Lender shall be
liable for any of the foregoing to the extent they arise from the gross
negligence or willful misconduct of the person to be indemnified.

         11.6. NON-RELIANCE ON AGENTS AND OTHER LENDERS. Each Lender agrees
that it has, independently and without reliance on the Agents or any other
Lender, and based on such documents and information as it has deemed
appropriate, made its own credit analysis of the Company and its Subsidiaries
and decision to enter into this Agreement and that it will, independently and
without reliance upon the Agents or any other Lender, and based on such
documents and information as it shall deem appropriate at the time, continue
to make its own analysis and decisions in taking or not taking action under
this Agreement or under any other Loan Document. No Agent shall be required
to keep itself informed, as to the performance or observance by any Obligor
of this Agreement or any of the other Loan Documents or any other document
referred to or provided for herein or therein or to inspect the Properties or
books of the Company or any of its Subsidiaries. Except for notices, reports
and other documents and information expressly required to be furnished to the
Lenders by the Agents hereunder, the Agents shall not have any duty or
responsibility to provide any Lender with any credit or other information
concerning the affairs, financial condition or business of the Company or any
of its Subsidiaries (or any of their affiliates) that may come into the
possession of any Agent or any of their respective affiliates.

         11.7. FAILURE TO ACT. Except for action expressly required of any
Agent hereunder and under the other Loan Documents, each Agent shall in all
cases be fully justified in failing or refusing to act hereunder and
thereunder unless it shall receive further assurances to its satisfaction
from the Lenders of their indemnification obligations under Section 11.5
hereof against any and all liability and expense that may be incurred by it
by reason of taking or continuing to take any such action.

         11.8. RESIGNATION OR REMOVAL OF AGENTS. Subject to the appointment
and acceptance of a successor Agent as provided below, an Agent may resign at
any time by giving notice thereof to the Lenders and the Company. Any Agent
may be removed as Agent hereunder upon the written consent of all Lenders
exclusive of such Agent upon the following: (i) willful misconduct in the
performance of such Agent's duties or responsibilities under this Agreement
as finally determined by a court of competent jurisdiction; or (ii) if a
receiver, trustee or conservator is appointed for such Agent or any state or
federal regulatory authority assumes management or control of such Agent or
if, under applicable law, the administrative or



                                      -61-




discretionary duties of such Agent hereunder become controlled by or subject
to the approval of any state or federal regulatory authority. Upon any such
resignation or removal, the Required Lenders shall have the right to appoint
a successor Agent to such capacity (and in that connection, so long as no
Event of Default shall have occurred and be continuing, subject to the
consent of the Company, not to be unreasonably withheld or delayed). If no
successor Agent shall have been so appointed by the Required Lenders and
shall have accepted such appointment within 30 days after such removal or the
retiring Agent's giving of notice of resignation then the retiring Agent may,
on behalf of the Lenders, appoint a successor Agent to such capacity, that
shall be a bank with a combined capital and surplus of at least $250,000,000
(and in that connection, so long as no Event of Default shall have occurred
and be continuing, subject to the consent of the Company, not to be
unreasonably withheld or delayed)). Upon the acceptance of any appointment as
an Agent hereunder by a successor Agent, (a) such successor Agent shall
thereupon succeed to and become vested with all the rights, powers,
privileges and duties of the retiring Agent and (b) the retiring Agent shall
be discharged from its duties and obligations hereunder. After any retiring
Agent's resignation or removal hereunder as an Agent, the provisions of this
Section 11 shall continue in effect for its benefit in respect of any actions
taken or omitted to be taken by it while it was acting as the Agent.

         11.9. CONSENTS UNDER OTHER LOAN DOCUMENTS. Except as otherwise
provided in Section 12.5 hereof with respect to this Agreement, the
Administrative Agent may, with the prior consent of the Required Lenders (but
not otherwise), consent to any modification, supplement or waiver under any
of the other Loan Documents, PROVIDED that, without the prior consent of each
Lender, the Administrative Agent shall not (except as provided herein)
release any collateral or any Obligor or otherwise terminate any Lien under
any Loan Document providing for collateral security, or agree to additional
obligations being secured by such collateral security.

Section 12.  MISCELLANEOUS

         12.1. WAIVER. No failure on the part of any Agent or any Lender to
exercise and no delay in exercising, and no course of dealing with respect to,
any right, power or privilege under this Agreement or any Note shall operate as
a waiver thereof, nor shall any single or partial exercise of any right, power
or privilege under this Agreement or any Note preclude any other or further
exercise thereof or the exercise of any other right, power or privilege. The
remedies provided herein are cumulative and not exclusive of any remedies
provided by law.

         Each Obligor irrevocably waives, to the fullest extent permitted by
applicable law, any claim that any action or proceeding commenced by any Agent
or any Lender relating in any way to this Agreement should be dismissed or
stayed by reason, or pending the resolution, of any action or proceeding
commenced by any Obligor relating in any way to this Agreement whether or not
commenced earlier. To the fullest extent permitted by applicable law, the
Obligors shall take all measures necessary for any such action or proceeding
commenced by any Agent or any Lender to proceed to judgment prior to the entry
of judgment in any such action or proceeding commenced by any Obligor.

         12.2. NOTICES. All notices, requests and other communications
provided for herein and under the Security Documents (including, without
limitation, any modifications of, or waivers, requests or consents under,
this Agreement) shall be given or made in writing

                                      -62-


(including, without limitation, by telecopy), or, with respect to notices
given pursuant to Section 2.3 hereof or Section 4.5 hereof, by telephone,
confirmed in writing by telecopier by the close of business on the day the
notice is given, delivered (or telephoned, as the case may be) to the
intended recipient at the "Address for Notices" specified below its name on
the signature pages hereof (below the name of the Company, in the case of any
Subsidiary Guarantor); or, as to any party, at such other address as shall be
designated by such party in a notice to each other party. Except as otherwise
provided in this Agreement, all such communications shall be deemed to have
been duly given when transmitted by telecopier or personally delivered or, in
the case of a mailed notice, upon receipt, in each case given or addressed as
aforesaid.

         12.3. EXPENSES, ETC. The Company agrees to pay or reimburse each of
the Lenders and each of the Agents for: (a) all reasonable out-of-pocket
costs and expenses of the Agents (including, without limitation, the
reasonable fees and expenses of Brown, Rudnick, Freed & Gesmer, special
counsel to Fleet) in connection with (i) the negotiation, preparation,
execution and delivery of this Agreement and the other Loan Documents and the
extensions of credit hereunder, (ii) the syndication of the Commitments and
the Loans and (iii) the negotiation or preparation of any modification,
supplement or waiver of any of the terms of this Agreement or any of the
other Loan Documents (whether or not consummated); (b) all reasonable
out-of-pocket costs and expenses of each of the Lenders and each of the
Agents (including, without limitation, the reasonable fees and expenses of
legal counsel) in connection with (i) any Default and any enforcement or
collection proceedings resulting therefrom, including, without limitation,
all manner of participation in or other involvement with (w) the exercise of
the Agents' and Lenders' rights under Section 9.3(f) hereof, (x) bankruptcy,
insolvency, receivership, foreclosure, winding up or liquidation proceedings,
(y) judicial or regulatory proceedings and (z) workout, restructuring or
other negotiations or proceedings (whether or not the workout, restructuring
or transaction contemplated thereby is consummated) and (ii) the enforcement
of this Section 12.3; and (c) all transfer, stamp, documentary or other
similar taxes, assessments or charges levied by any governmental or revenue
authority in respect of this Agreement or any of the other Loan Documents or
any other document referred to herein or therein and all reasonable costs,
expenses, taxes, assessments and other charges incurred in connection with
any filing, registration, recording or perfection of any security interest
contemplated by any Loan Document or any other document referred to therein.

         12.4. INDEMNIFICATION. The Company hereby agrees to indemnify each
Agent, each Lender, their affiliates and their respective directors,
officers, employees, attorneys and agents from, and hold each of them
harmless against, any and all losses, liabilities, claims, damages or
expenses incurred by any of them (including, without limitation, any and all
losses, liabilities, claims, damages or expenses incurred by any Agent to any
Lender, whether or not any Agent or any Lender is a party thereto) arising
out of or by reason of any investigation or litigation or other proceedings
(including any threatened investigation or litigation or other proceedings)
relating to this Agreement, any of the other Loan Documents, or the
extensions of credit hereunder or any actual or proposed use by the Company
or any of its Subsidiaries of the proceeds of any of the extensions of credit
hereunder, including, without limitation, the reasonable fees and
disbursements of counsel incurred in connection with any such investigation
or litigation or other proceedings or otherwise in connection with any
subpoena or similar document or order served on any Lender (but excluding any
such losses, liabilities, claims, damages or expenses incurred by reason of
the gross negligence or willful misconduct of the



                                      -63-


Person to be indemnified). Without limiting the generality of the foregoing,
the Company will indemnify each Agent and each Lender from, and hold each
Agent and each Lender harmless against, any losses, liabilities, claims,
damages or expenses described in the preceding sentence (but excluding, as
provided in the preceding sentence, any loss, liability, claim, damage or
expense incurred by reason of the gross negligence or willful misconduct of
the Person to be indemnified) arising under any Environmental Law as a result
of (i) the past, present or future operations of the Company or any of its
Subsidiaries (or any predecessor in interest to the Company or any of its
Subsidiaries), (ii) the past, present or future condition of any site or
facility owned, operated or leased at any time by the Company or any of its
Subsidiaries (or any such predecessor in interest) or (iii) any Release or
threatened Release of any Hazardous Materials at or from any such site or
facility, including any such Release or threatened Release that shall occur
during any period when any Agent or any Lender shall be in possession of any
such site or facility following the exercise by the Administrative Agent or
any Lender of any of its rights and remedies hereunder. In the case of an
investigation, litigation, or proceeding to which the indemnity described in
this paragraph applies, such indemnity shall be effective whether or not such
investigation, litigation, or proceeding is brought by the Company, its
shareholders or creditors or Person to be indemnified, or whether or not a
Person to be indemnified is otherwise a party thereto.

         12.5. AMENDMENTS, ETC.. Except as otherwise expressly provided in
this Agreement, any provision of this Agreement may be modified or
supplemented only by an instrument in writing signed by the Company, the
Administrative Agent and the Required Lenders, or by the Company and the
Administrative Agent acting with the consent of the Required Lenders, and any
provision of this Agreement may be waived by the Required Lenders or by the
Administrative Agent acting with the consent of the Required Lenders;
PROVIDED that: (a) no modification, supplement or waiver shall, unless by an
instrument signed by all of the Lenders or by the Administrative Agent acting
with the consent of all of the Lenders: (i) increase, or extend the term of
any of the Commitments, or extend the time or waive any requirement for the
increase, reduction or termination of any of the Commitments, (ii) extend or
postpone the date fixed for the payment of principal of or interest on any
Loan, or any fee hereunder, (iii) reduce the amount of any such payment of
principal, (iv) reduce the rate at which interest is payable thereon or any
fee is payable hereunder, (v) alter the rights or obligations of the Company
to prepay Loans, (vi) alter the terms of Section 4.2, 4.7 or 11.9 hereof or
this Section 12.5, (vii) modify the definition of the term "Required
Lenders", or modify in any other manner the number or percentage of the
Lenders required to make any determinations or waive any rights hereunder or
to modify any provision hereof, (viii) release any Obligor hereunder, (ix)
waive any of the conditions precedent set forth in Section 7.1 hereof, or (x)
release the pledge of stock of Genzyme Securities Corporation, other than in
exchange for a pledge of stock of the surviving entity under the terms of
Section 9.5(d)(i) hereof; (b) any modification or supplement of Section 11
hereof shall require the consent of the Administrative Agent; and (c) any
modification or supplement of Section 6 hereof shall require the consent of
each Subsidiary Guarantor (PROVIDED that any Subsidiary of the Company may
become a party to this Agreement as a "Subsidiary Guarantor" hereunder as
provided in Section 9.13 hereof).

         12.6. SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon
and inure to the benefit of the parties hereto and their respective permitted
successors and assigns.



                                      -64-



         12.7. ASSIGNMENTS AND PARTICIPATIONS.

                  (a) No Obligor may assign any of its rights or obligations
         hereunder or under the Notes without the prior consent of all of the
         Lenders and the Agent.

                  (b) Each Lender may assign any of its Loans, its Note and its
         Commitment but only with the consent of the Company and the
         Administrative Agent; PROVIDED THAT

                                    (i) no such consent by the Company or the
                  Administrative Agent shall be required in the case of any
                  assignment to another Lender or to an Affiliate of any Lender,
                  and no such consent by the Company shall be required in the
                  case of any assignment effected while an Event of Default has
                  occurred and is continuing;

                                    (ii) except to the extent the Company and
                  the Administrative Agent shall otherwise consent, any such
                  partial assignment (other than to another Lender) shall be in
                  an amount at least equal to $5,000,000;

                                    (iii) upon each such assignment, the
                  assignor and assignee shall deliver to the Company and the
                  Administrative Agent a Notice of Assignment in the form of
                  EXHIBIT F hereto; and

                                    (iv) no consent required of the Company or
                  the Administrative Agent under this Section 12.7(b) shall be
                  unreasonably withheld or delayed.

                  Upon execution and delivery by the assignor and the assignee
         to the Company and the Administrative Agent of such Notice of
         Assignment and upon the consent thereto by the Company and the
         Administrative Agent, the assignee shall have, to the extent of such
         assignment (unless otherwise consented to by the Company and the
         Administrative Agent), the obligations, rights and benefits of a Lender
         hereunder holding the Commitment(s) and Loans (or portions thereof)
         assigned to it and specified in such Notice of Assignment (in addition
         to the Commitment(s) and Loans, if any, theretofore held by such
         assignee) and the assigning Lender shall, to the extent of such
         assignment, be released from the Commitment(s) (or portion(s) thereof)
         so assigned. Upon each such assignment the assigning Lender shall pay
         the Administrative Agent an assignment fee of $4,500.

                  (c) Each Lender shall have the unrestricted right at any time
         and from time to time, and without the consent of or notice to the
         Company, any Subsidiary Guarantor, any Agent, or any other Lender, to
         grant to one or more banks or other financial institutions (each, a
         "Participant") participating interests in such Lender's obligations to
         lend hereunder and/or any or all of the Loans held by such Lender
         hereunder. In the event of any such grant by a Lender of a
         participating interest to a Participant, whether or not upon notice to
         the Company, any Subsidiary Guarantor, any Agent, or any other Lender,
         such Lender shall be responsible for the performance of its obligations
         hereunder and the Company, Agents, and other Lenders shall continue to
         deal solely and directly



                                      -65-


         with such Lender in connection with such Agents' and Lenders' rights
         and obligations hereunder.

                  (d) In addition to the assignments and participations
         permitted under the foregoing provisions of this Section 12.7, any
         Lender may (without notice to the Company, the Administrative Agent or
         any other Agent or Lender and without payment of any fee) (i) assign
         and pledge all or any portion of its Loans, and Notes to any Federal
         Reserve Bank as collateral security pursuant to Regulation A and any
         Operating Circular issued by such Federal Reserve Bank and (ii) assign
         all or any portion of its rights under this Agreement and its Loans,
         and Note to an Affiliate of such Lender provided that the Company shall
         not be required to pay any increase in the cost of borrowing as a
         result of such assignment and LIBOR Loans must continue to be made
         available by such Assignee.

                  (e) A Lender may furnish any information concerning the
         Company or any of its Subsidiaries in the possession of such Lender
         from time to time to assignees and participants (including prospective
         assignees and participants), subject, however, to the provisions of
         Section 12.13 hereof.

                  (f) Anything in this Section 12.7 to the contrary
         notwithstanding, no Lender may assign or participate any interest in
         any Commitment or Loan held by it hereunder to the Company or any of
         its Affiliates or Subsidiaries, and the Company shall not, and shall
         not permit any of its Subsidiaries to, acquire any such interest in any
         Commitment or Loan, without the prior consent of each Lender.

         12.8. SURVIVAL. The obligations of the Company under Sections 5.1, 5.5,
12.3, and 12.4 hereof, the obligations of each Subsidiary Guarantor under
Section 6.3 hereof, and the obligations of the Lenders under Section 11.5
hereof, shall survive the repayment of the Loans and the termination of the
Commitments and, in the case of any Lender that may assign any interest in its
Commitments or Loans hereunder, shall survive the making of such assignment,
notwithstanding that such assigning Lender may cease to be a "Lender" hereunder.
In addition, each representation and warranty made, or deemed to be made by a
notice of borrowing herein or pursuant hereto shall survive the making of such
representation and warranty, and no Lender shall be deemed to have waived, by
reason of making any extension of credit, any Default that may arise by reason
of such representation or warranty proving to have been false or misleading,
notwithstanding that such Lender or any Agent may have had notice or knowledge
or reason to believe that such representation or warranty was false or
misleading at the time such extension of credit was made.

         12.9. CAPTIONS. The table of contents and captions and section headings
appearing herein are included solely for convenience of reference and are not
intended to affect the interpretation of any provision of this Agreement.

         12.10. COUNTERPARTS. This Agreement may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument and any of the parties hereto may execute this Agreement by signing
any such counterpart.



                                      -66-



         12.11. GOVERNING LAW; SUBMISSION TO JURISDICTION. This Agreement and
the Notes shall be governed by, and construed in accordance with, the law of
The Commonwealth of Massachusetts. Each Obligor hereby submits to the
nonexclusive jurisdiction of the United States District Court for the
District of Massachusetts and of the Superior Court of the Commonwealth of
Massachusetts sitting in Suffolk County, and any appellate court in the
Commonwealth of Massachusetts, for the purposes of all legal proceedings
arising out of or relating to this Agreement or the transactions contemplated
hereby. Each Obligor hereby irrevocably waives, to the fullest extent
permitted by applicable law, any objection that it may now or hereafter have
to the laying of the venue of any such proceeding brought in such a court and
any claim that any such proceeding brought in such a court has been brought
in an inconvenient forum.

         12.12. WAIVER OF JURY TRIAL. EACH OF THE OBLIGORS, THE AGENTS AND THE
LENDERS HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE
LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF
OR RELATING TO THIS AGREEMENT, THE NOTES OR THE TRANSACTIONS CONTEMPLATED
HEREBY.

         12.13. CONFIDENTIALITY.

                  (a) The Company acknowledges that from time to time financial
         advisory, investment banking and other services may be offered or
         provided to the Company or one or more of its Subsidiaries (in
         connection with this Agreement or otherwise) by any Lender or by one or
         more subsidiaries or affiliates of such Lender and the Company hereby
         authorizes each Lender to share any information delivered to such
         Lender by the Company and its Subsidiaries pursuant to this Agreement
         and the other Loan Documents, or in connection with the decision of
         such Lender to enter into this Agreement, to any such subsidiary or
         affiliate, it being understood that any such subsidiary or affiliate
         receiving such information shall be bound by the provisions of
         paragraph (b) below as if it were a Lender hereunder. Such
         authorization shall survive the repayment of the Loans and the
         termination of the Commitments.

                  (b) Each Lender and each Agent agrees (on behalf of itself and
         each of its affiliates, directors, officers, employees and
         representatives) to keep confidential, in accordance with their
         customary procedures for handling confidential information of the same
         nature and in accordance with safe and sound banking practices, any
         non-public information supplied to it by the Company pursuant to this
         Agreement and the other Documents, provided that nothing herein shall
         limit the disclosure of any such information (i) to the extent required
         by statute, rule, regulation or judicial process, (ii) to counsel for
         any of the Lenders or the Agents, (iii) to bank examiners, auditors or
         accountants, (iv) to any other Agent or any other Lender, (v) in
         connection with any litigation to which any one or more of the Lenders
         or one or more of the Agents is a party in which such Lender or the
         Agents has been required or, in the opinion of its legal counsel, deems
         it necessary to produce such information, (vi) to a subsidiary or
         affiliate of such Lender as provided in paragraph (a) above or (vii) to
         any assignee or participant (or prospective assignee or participant)
         assignee or participant (or prospective assignee or participant);
         provided, further, that (x) unless specifically prohibited by
         applicable law or court order, each Lender and each Agent shall, prior
         to disclosure thereof, notify



                                      -67-



         the Company of any request for disclosure of any such non-public
         information, except when the request is (A) made by any governmental
         agency or representative thereof or (B) pursuant to legal process and
         (y) that in no event shall any Lender or any Agent be obligated to
         return any materials furnished by the Company. The obligations of each
         Lender under this Section 12.13 shall supersede and replace the
         obligations of such Lender under the confidentiality letter in respect
         of this financing signed and delivered by such Lender to the Company
         prior to the date hereof.

         12.14. COMPLIANCE WITH USURY LAWS.

         All agreements between any Obligor, the Agents, and any Lender are
hereby expressly limited so that in no contingency or event whatsoever, whether
by reason of acceleration of maturity of the indebtedness evidenced hereby or
otherwise, shall the amount paid or agreed to be paid to any Agent or any Lender
for the use or the forbearance of the indebtedness evidenced hereby exceed the
maximum permissible under applicable law. As used herein, the term "applicable
law" shall mean the law in effect as of the date hereof, PROVIDED, HOWEVER, that
in the event there is a change in the law which results in a higher permissible
rate of interest, then this Agreement shall be governed by such new law as of
its effective date. In this regard, it is expressly agreed that it is the intent
of the Obligors, the Agents and the Lenders in the execution, delivery and
acceptance of this Agreement to contract in strict compliance with the laws of
the Commonwealth of Massachusetts from time to time in effect. If, under or from
any circumstances whatsoever, fulfillment of any provision hereof or of any of
the Loan Documents at the time performance of such provision shall be due, shall
involve transcending the limit of validity prescribed by applicable law, then
the obligation to be fulfilled shall automatically be reduced to the limit of
such validity, and if under or from any circumstances whatsoever any Agent or
any Lender should ever receive as interest an amount which would exceed the
highest lawful rate, such amount which would be excessive interest shall be
applied to the reduction of the principal balance evidenced hereby and not to
the payment of interest. This provision shall control every other provision of
all agreements between the Obligors, the Agents, and the Lenders.

         12.15. REPLACEMENT NOTE.

         Upon receipt of an affidavit of an officer of any Agent or any Lender
as to the loss, theft, destruction or mutilation of any Revolving Credit Note or
any other Loan Documents which is not of public record, and, in the case of any
such loss, theft, destruction or mutilation, upon receipt of an affidavit of
surrender and cancellation of such Revolving Credit Note or other Loan Document,
the Company will issue, in lieu thereof, a replacement Revolving Credit Note or
other Loan Document in the same principal amount thereof and otherwise of like
tenor.

         12.16. TRANSITIONAL ARRANGEMENTS. This Agreement, upon the satisfaction
of each of the conditions set forth in Section 7 shall amend, replace and
supercede the Prior Credit Agreement, provided that each of the Obligations
outstanding under the Prior Credit Agreement shall become Obligations under this
Agreement and all interest, fees and charges payable under the Prior Credit
Agreement shall continue in effect and be payable as provided under this
Agreement subject to any change or modification thereto that is provided in this
Agreement.



                                      -68-





         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered as an instrument under seal as of the day and year
first above written.

                               GENZYME CORPORATION


                               By: /s/ Michael S. Wyzga
                                   --------------------------------------------
                                   Michael S. Wyzga
                                   Senior Vice President, Finance

                               Address for Notices:

                               Genzyme Corporation
                               15 Pleasant Street Connector
                               Framingham, Massachusetts 01701
                               Attention:  Evan M. Lebson, Treasurer

                               Telecopier No.: (508) 872-0827
                               Telephone No.:  (508) 270-2334

                               SUBSIDIARY GUARANTORS

                               DEKNATEL SNOWDEN PENCER, INC.



                               By: /s/ Earl M. Collier, Jr.
                                   --------------------------------------------
                                   Earl M. Collier, Jr.
                                   President

                               Address for Notices:

                               c/o Genzyme Corporation
                               15 Pleasant Street Connector
                               Framingham, MA 01701
                               Attention:  Evan M. Lebson, Treasurer

                               Telecopier No.: (508) 872-0827
                               Telephone No.: (508) 270-2334






                               GENZYME SURGICAL PRODUCTS
                               CORPORATION


                               By: /s/ Evan M. Lebson
                                   ---------------------------------------------
                                   Evan M. Lebson
                                   Treasurer

                               Address for Notices:

                               c/o Genzyme Corporation
                               15 Pleasant Street Connector
                               Framingham, MA 01701
                               Attention:  Evan M. Lebson, Treasurer

                               Telecopier No.: (508) 872-0827
                               Telephone No.: (508) 270-2334






                               ADMINISTRATIVE AGENT

                               FLEET NATIONAL BANK


                               By:  /s/ Kimberly A. Martone
                                    --------------------------------------------
                                    Kimberly A. Martone
                                    Senior Vice President/Director

                               ADDRESS FOR NOTICES:
                               -------------------

                               Fleet National Bank
                               One Federal Street
                               Boston, MA 02110
                               Attention:  Kimberly A. Martone, Senior Vice
                               President - High Tech Group

                               Telecopier No.:  (617) 434-2473
                               Telephone No.:   (617) 434-5316







                                SYNDICATION AGENT

                                ABN AMRO BANK N.V.

                                By:  /s/ ABN AMRO Bank N.V.
                                     -------------------------------------------
                                     Title: Senior Vice President

                                     /s/ Patricia Christy
                                     -------------------------------------------
                                     Title: Vice President

                                ADDRESS FOR NOTICES:
                                -------------------
                                ABN AMRO Bank N.V.
                                -------------------
                                500 Park Avenue
                                -------------------
                                New York, NY 10022
                                -------------------

                                Attention: Patricia Christy
                                           --------------------------------
                                Telecopier No.: (212) 446-4237
                                                ---------------------------
                                Telephone No.: (212) 446-4204
                                               ----------------------------




                                DOCUMENTATION AGENT

                                FIRST UNION NATIONAL BANK

                                By:  /s/ Michael Monte
                                     -------------------------------------------
                                     Title: Managing Director


                                ADDRESS FOR NOTICES:
                                -------------------
                                Joyce Barry
                                -------------------
                                201 S. College Street, 6th Floor
                                -------------------
                                Charlotte, NC 28288-0760
                                -------------------

                                Attention: Joyce Barry
                                           --------------------------------
                                Telecopier No.: (704) 374-4793
                                                ---------------------------
                                Telephone No.: (704) 374-4151
                                               ----------------------------




                                     LENDER

                                FLEET NATIONAL BANK


                                By:  /s/ Kimberly Marbre
                                     -------------------------------------------
                                     Title: SVP/Director

                                ADDRESS FOR NOTICES:
                                -------------------

                                Fleet National Bank
                                One Federal Street
                                Boston, MA 02110
                                Attention:  Kimberly A. Martone, Senior Vice
                                President - High Tech Group

                                Telecopier No.:  (617) 434-2473
                                Telephone No.:  (617) 434-5316

                                LENDING OFFICE FOR ALL LOANS:
                                ----------------------------

                                Fleet National Bank
                                One Federal Street
                                Boston, MA 02110
                                Attention:  Kimberly A. Martone, Senior Vice
                                President - High Tech Group


                                Telecopier No.:  (617) 434-2473
                                Telephone No.:   (617) 434-5316


INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $11,025,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $25,725,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $15,750,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $36,750,000.00





                                         LENDER
                                         ------

                                         ABN AMRO BANK N.V.

                                         By: /s/ ABN AMRO Bank N.V.
                                             ---------------------------------
                                             Title: Senior Vice President

                                         By: /s/ Patricia Christy
                                             ---------------------------------
                                             Title: Vice President


                                         Address for Notices:
                                         --------------------

                                         ABN AMRO Bank N.V.
                                         500 Park Avenue
                                         New York, NY 10022
                                         Attn: Patricia Christy

                                         Telecopier No.: (212) 446-4237
                                         Telephone No.: (212) 446-4204

                                         Lending Office for all Loans:
                                         -----------------------------

                                         ABN AMRO Bank N.V.
                                         208 South LaSalle Street
                                         Suite 1500
                                         Chicago, IL 60604-1003
                                         Attn: Loan Administration

                                         Telecopier No.: 312 992 5111
                                         Telephone No.:  312 992 5096

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 9,975,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $23,275,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $14,250,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $33,250,000.00



                                         LENDER
                                         ------

                                         FIRST UNION NATIONAL BANK

                                         By: /s/ Michael Monte
                                             ---------------------------------
                                             Title: Managing Director


                                         Address for Notices:
                                         --------------------

                                         Joyce Barry
                                         201 S. College Street, 6th Floor
                                         Charlotte, NC 28288-0760
                                         Attention: Joyce Barry
                                         --------------------------------------
                                         Telecopier No.: 704-374-4793
                                         Telephone No.: 704-374-4151

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Tonya Rhyne
                                         201 S. College St., CP-24
                                         Charlotte, NC 28288-118

                                         Attn: Tonya Rhyne
                                         Telecopier No.: 704-383-5295
                                         Telephone No.:  704-383-7201

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 9,975,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $23,275,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $14,250,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $33,250,000.00



                                         LENDER
                                         ------

                                         THE BANK OF NOVA SCOTIA

                                         By: /s/ T.M. Pitcher
                                             ---------------------------------
                                             Title:
                                             Authorized Signatory


                                         Address for Notices:
                                         --------------------

                                         The Bank of Nova Scotia
                                         600 Peachtree Street, N.E.
                                         Suite 2700
                                         Atlanta, GA 30308
                                         Attn: Jill A. Quiroz

                                         Telecopier No.: (404) 888-8998
                                         Telephone No.: (404) 877-1544

                                         Lending Office for all Loans:
                                         -----------------------------

                                         The Bank of Nova Scotia
                                         Boston Branch
                                         28 State Street, 17th Floor
                                         Boston, MA 02109
                                         Attn: Stephen Foley

                                         Telecopier No.: (617) 624-7607
                                         Telephone No.:  (617) 624-7612

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 8,925,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $20,825,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $12,750,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $29,750,000.00


                                         LENDER
                                         ------

                                         SOCIETE GENERALE

                                         By: /s/ Richard Bernal
                                             ---------------------------------
                                             Title: Vice President


                                         Address for Notices:
                                         --------------------

                                         Societe Generale
                                         2001 Ross Avenue
                                         Suite 4800
                                         Dallas, TX 75201
                                         Attn: Aretha Velasquez

                                         Telecopier No.: (214) 754-0171
                                         Telephone No.: (214) 979-2758

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Societe Generale
                                         1221 Avenue of the Americas
                                         New York, NY 10020

                                         Attn: Jay Sands

                                         Telecopier No.: (212) 278-7614
                                         Telephone No.:  (212) 278-6697

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 8,925,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $20,825,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $12,750,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $29,750,000.00


                                         LENDER
                                         ------

                                         THE INDUSTRIAL BANK OF JAPAN,
                                          LIMITED

                                         By: /s/ J. Kenneth Biegen
                                             ---------------------------------
                                             Title: Senior Vice President


                                         Address for Notices:
                                         --------------------

                                         The Industrial Bank of Japan, Limited
                                         1251 Avenue of the Americas
                                         New York, NY 10020-1104
                                         Attn: Wayne Wright

                                         Telecopier No.: (212) 282-4488
                                         Telephone No.: (212) 282-3462

                                         Attn: J. Kenneth Biegen

                                         Telecopier No.: (212) 282-4488
                                         Telephone No.: (212) 282-3460

                                         Lending Office for all Loans:
                                         -----------------------------

                                         The Industrial Bank of Japan, Limited
                                         1251 Avenue of the Americas
                                         New York, NY 10020
                                         Attn: Domestic Money Market Lending
                                               Office

                                         Telecopier No.: (212) 282-4250
                                         Telephone No.:  (212) 282-3000

                                         Attn: LIBOR Lending Office

                                         Telecopier No.: (212) 282-4250
                                         Telephone No.:  (212) 282-3000

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $2,975,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $6,941,666.67

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $4,250,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $9,916,666.67


                                         LENDER
                                         ------

                                         THE FUJI BANK, LIMITED

                                         By: /s/ The Fuji Bank, Limited
                                             ---------------------------------
                                             Title: Vice President & Manager


                                         Address for Notices:
                                         --------------------

                                         The Fuji Bank, Limited
                                         2 World Trade Center
                                         79 Floor
                                         New York, NY 10048
                                         Attn: Chigusa Tada

                                         Telecopier No.: 212-321-9407
                                         Telephone No.: 212-898-2067

                                         Lending Office for all Loans:
                                         -----------------------------

                                         The Fuji Bank, Limited
                                         2 World Trade Center
                                         79 Floor
                                         New York, NY 10048
                                         Attn: Tina Catapano

                                         Telecopier No.: 212-488-8216
                                         Telephone No.: 212-898-2099

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $2,975,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $6,941,666.67

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $4,250,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $9,916,666.67


                                         LENDER
                                         ------

                                         THE DAI-ICHI KANGYO BANK, LIMITED

                                         By: /s/ The Dai-Ichi Kangyo Bank,
                                                 Limited
                                             ---------------------------------
                                             Title: Senior Vice-President


                                         Address for Notices:
                                         --------------------

                                         The Dai-ichi Kangyo Bank, Limited
                                         One World Trade Center
                                         48th Floor
                                         New York, NY 10048
                                         Attn: Ivan Lincevski

                                         Telecopier No.: (212) 912-1879
                                         Telephone No.: (212) 432-6632

                                         Lending Office for all Loans:
                                         -----------------------------

                                         The Dai-ichi Kangyo Bank, Limited
                                         One World Trade Center
                                         48th Floor
                                         New York, NY 10048
                                         Attn: Ivan Lincevski

                                         Telecopier No.: (212) 912-1879
                                         Telephone No.: (212) 432-6632

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $2,975,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $6,941,666.67

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $4,250,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $9,916,666.67


                                         LENDER
                                         ------

                                         BANK OF TOKYO-MITSUBISHI TRUST
                                         COMPANY

                                         By: /s/ Thomas Fennessey
                                             ---------------------------------
                                             Title: Vice President


                                         Address for Notices:
                                         --------------------

                                         Bank of Tokyo-Mitsubishi Trust Company
                                         1251 Avenue of the Americas
                                         12th Floor
                                         New York, NY 10020
                                         Attn: Thomas Fennessey

                                         Telecopier No.: (212) 782-6440
                                         Telephone No.: (212) 782-4221

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Bank of Tokyo-Mitsubishi Trust Company
                                         1251 Avenue of the Americas
                                         12th Floor
                                         New York, NY 10020
                                         Attn: Rolando Uy

                                         Telecopier No.: (201) 521-2304
                                         Telephone No.: (201) 413-8570

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 7,350,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $17,150,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $10,500,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $24,500,000.00


                                         LENDER
                                         ------

                                         THE CHASE MANHATTAN BANK

                                         By: /s/ John A. Francis
                                             ---------------------------------
                                             Title: Vice President


                                         Address for Notices:
                                         --------------------

                                         The Chase Manhattan Bank
                                         999 Broad Street, 1st Floor
                                         Bridgeport, CT 06510
                                         Attn: John Francis

                                         Telecopier No.: 203-784-3838
                                         Telephone No.: 860-633-7799

                                         Lending Office for all Loans:
                                         -----------------------------

                                         The Chase Manhattan Bank
                                         999 Broad Street, 1st Floor
                                         Bridgeport, CT 06510
                                         Attn: Jackie Santana

                                         Telecopier No.: 203-368-5124
                                         Telephone No.: 203-382-6575

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 7,350,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $17,150,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $10,500,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $24,500,000.00


                                         LENDER
                                         ------

                                         CITIZENS BANK OF MASSACHUSETTS

                                         By: /s/ Scott Haskell
                                             ---------------------------------
                                             Title: Vice President


                                         Address for Notices:
                                         --------------------

                                         Citizens Bank of Massachusetts
                                         53 State Street
                                         Boston, MA 02109
                                         Attn: Scott Haskell

                                         Telecopier No.: (617) 742-9548
                                         Telephone No.: (617) 994-7129

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Citizens Bank of Massachusetts
                                         53 State Street
                                         Boston, MA 02109
                                         Attn: Scott Haskell

                                         Telecopier No.: (617) 742-9548
                                         Telephone No.: (617) 994-7129

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 7,350,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $17,150,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $10,500,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $24,500,000.00


                                         LENDER
                                         ------

                                         CITIZENS BANK OF MASSACHUSETTS

                                         By: /s/ J. Wade Bell
                                             ---------------------------------
                                             Title: Vice President


                                         Address for Notices:
                                         --------------------

                                         1735 Market Street, 7th Fl.
                                         Philadelphia, PA 19103
                                         Attn: J. Wade Bell

                                         Telecopier No.: 215-553-4899
                                         Telephone No.: 215-553-3875

                                         Lending Office for all Loans:
                                         -----------------------------

                                         3 Mellon Bank Center, 12th Fl.
                                         Pittsburgh, PA 15259
                                         Attn: Sannford M. Richards

                                         Telecopier No.: 412-209-6118
                                         Telephone No.: 412-234-8285

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 7,350,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $17,150,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $10,500,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $24,500,000.00


                                         LENDER
                                         ------

                                         BANCA NAZIONALE DEL LAVORO S.p.A.
                                         NEW YORK BRANCH

                                         By: /s/ Leonardo Valentini
                                             ---------------------------------
                                             Title: First Vice President

                                         By: /s/ Frederic W. Hall
                                             ---------------------------------
                                             Title: Vice President

                                         Address for Notices:
                                         --------------------

                                         Banca Nazionale del Lavoro SPA,
                                         New York Branch
                                         25 West 51 Street
                                         New York, NY 10019
                                         Tel.: 212-314-0679
                                         Fax:  212-765-2978
                                         Attn: Anna Hernandez

                                         Telecopier No.: 212-765-2978
                                         Telephone No.: 212-314-0679

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Banca Nazionale del Lavoro SPA,
                                         New York Branch
                                         25 West 51 Street
                                         New York, NY 10019
                                         Tel.: 212-314-0263
                                         E-Mail: Frederic.Hall@bnlmail.com
                                         Fax:  212-765-2978
                                         Attn: Frederic W. Hall

                                         Telecopier No.: 212-765-2978
                                         Telephone No.: 212-314-0263

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 4,200,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $ 9,800,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $ 6,000,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $14,000,000.00


                                         LENDER
                                         ------

                                         CREDIT SUISSE FIRST BOSTON

                                         By: /s/ William S. Lutkins
                                             ---------------------------------
                                             Title: Vice President

                                         By: /s/ William O'Daly
                                             ---------------------------------
                                             Title: Vice President

                                         Address for Notices:
                                         --------------------

                                         11 Madison Avenue
                                         New York, NY 10010
                                         Attn: William S. Lutkins

                                         Telecopier No.: (212) 325-8319
                                         Telephone No.: (212) 325-9705

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Same as above


INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 4,200,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $ 9,800,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $ 6,000,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $14,000,000.00


                                         LENDER
                                         ------

                                         KBC BANK N.V.

                                         By: /s/ Robert Snauffer
                                             ---------------------------------
                                             Title: First Vice President

                                         By: /s/ Robert M. Surdam, Jr.
                                             ---------------------------------
                                             Title: Vice President

                                         Address for Notices:
                                         --------------------

                                         KBC Bank N.V.
                                         125 West 55th Street, 10th Floor
                                         New York, NY 10019
                                         Attn: Robert Surdam

                                         Telecopier No.: (212) 541-0793
                                         Telephone No.: (212) 541-0704

                                         Lending Office for all Loans:
                                         -----------------------------

                                         KBC Bank N.V.
                                         125 West 55th Street, 10th Floor
                                         New York, NY 10019
                                         Attn: Robert Surdam

                                         Telecopier No.: (212) 541-0793
                                         Telephone No.: (212) 541-0704


INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 4,200,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $ 9,800,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $ 6,000,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $14,000,000.00


                                         LENDER
                                         ------

                                         BANK LEUMI U.S.A.

                                         By: /s/ Bank Leumi U.S.A.
                                             ---------------------------------
                                             Title: FVP

                                         By: /s/ Bank Leumi U.S.A.
                                             ---------------------------------
                                             Title: SVP

                                         Address for Notices:
                                         --------------------

                                         Bank Leumi U.S.A.
                                         562 Fifth Avenue
                                         10th Floor
                                         New York, NY 10036
                                         Attn: Paul Tine

                                         Telecopier No.: (212) 626-1811
                                         Telephone No.: (212) 626-1386

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Bank Leumi U.S.A.
                                         562 Fifth Avenue
                                         10th Floor
                                         New York, NY 10036
                                         Attn: Paul Tine

                                         Telecopier No.: (212) 626-1811
                                         Telephone No.: (212) 626-1386

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $ 3,150,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $ 7,350,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $ 4,500,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $10,500,000.00


                                         LENDER
                                         ------

                                         BANK HAPOALIM B.M.

                                         By: /s/ Bank Hapoalim B.M.
                                             ---------------------------------
                                             Title: First Vice President

                                         By: /s/ Gabriel Lubiner
                                             ---------------------------------
                                             Title: Assistant Vice President

                                         Address for Notices:
                                         --------------------

                                         Bank Hapoalim
                                         1177 Avenue of the Americas
                                         12th Floor
                                         New York, NY 10036
                                         Attn: Gabriel Lubiner

                                         Telecopier No.: (212) 782-2187
                                         Telephone No.: (212) 782-2197

                                         Lending Office for all Loans:
                                         -----------------------------

                                         Bank Hapoalim
                                         1177 Avenue of the Americas
                                         12th Floor
                                         New York, NY 10036
                                         Attn: Donna Gindoff

                                         Telecopier No.: (212) 782-2187
                                         Telephone No.: (212) 782-2197

INITIAL 364-DAY REVOLVING CREDIT AVAILABILITY:                    $2,100,000.00
INITIAL THREE-YEAR REVOLVING CREDIT AVAILABILITY:                 $4,900,000.00

POST-SECOND ACQUISITION 364-DAY REVOLVING CREDIT COMMITMENT:      $3,000,000.00
POST-SECOND ACQUISITION THREE-YEAR REVOLVING CREDIT COMMITMENT:   $7,000,000.00



                                  SCHEDULE 8.3
                                   LITIGATION

                                      None.






                                 SCHEDULE 8.12A
                   INDEBTEDNESS EVIDENCE BY CREDIT AGREEMENTS,
                   INDENTURES, GUARANTEES, LETTERS OF CREDIT, ETC.



                        
$18,000,000                Revolving credit facility borrowing under Prior Credit Agreement
                           (to be paid on the Closing Date)

$26,350,000                Guaranty of Genzyme Transgenics Corporation credit facilities with
                           and letters of credit issued by Fleet National Bank

$ 6,040,000                Guaranty issued to Barclays Bank, PLC to secure duty
                           deferment account

$ 48,000,000               Genzyme Corporation Guarantee of GelTex Pharmaceuticals, Inc. credit facilities with
                           Fleet National Bank and synthetic lease transaction with First Security Bank, N.A., as
                           Owner Trustee, Fleet Real Estate, Inc. and Fleet National Bank

$25,000,000                Synthetic lease transaction between GelTex Pharmaceuticals, Inc. and First Security
                           Bank, N.A., as Owner Trustee

$ 3,000,000                GelTex Pharmaceuticals, Inc. revolving credit facility with Fleet National Bank

$ 1,987,000                GelTex Pharmaceuticals, Inc. term loan financing leasehold improvements with Fleet
                           National Bank

$ 1,929,000                GelTex Pharmaceuticals, Inc. term loan financing leasehold improvements with Fleet
                           National Bank

- ------------------
$130,306,000               TOTAL






                                 SCHEDULE 8.12B
                           LIENS SECURING INDEBTEDNESS




Equipment and leasehold improvements of GelTex Pharmaceuticals, Inc. securing
credit facilities with Fleet National Bank, together with securities and
investments of GelTex Pharmaceuticals, Inc. securing credit facilities with
Fleet National Bank.






                                  SCHEDULE 8.14
                                   SUBSIDIARIES

                           SEE CHART ATTACHED HERETO.


                     Assets by Subsidiary (Greater than 3%)

                             As of December 31, 1999



Subsidiary                                           Book Value (Millions)      % Of Total
- --------------------------------------------------------------------------------------------------
                                                                          
Genzyme Securities Corporation                       $  514.6                    28.8%

Deknatel Snowden Pencer, Inc. and
Genzyme Surgical Products Corporation                $  361.0                    20.2%

Allston Landing Limited Partnership-                 $   79.5                     4.4%

Genzyme Limited (UK)                                 $   64.6                     3.6%

Subtotal                                             $1,019.7                    57.1%

Genzyme Corporation (Total)                                 $1,787.3                  100.0%





                                                                   EXHIBIT A

               [Form of Three-Year Facility Revolving Credit Note]

                                 PROMISSORY NOTE
                              (Three-Year Facility)
$______________                                              December 14, 2000
                                                         Boston, Massachusetts

         FOR VALUE RECEIVED, GENZYME CORPORATION, a Massachusetts corporation
(the "COMPANY"), hereby promises to pay to _______________ (the "LENDER"), for
account of its respective Applicable Lending Offices provided for by the Credit
Agreement referred to below, at the principal office of Fleet National Bank, 100
Federal Street, Boston, Massachusetts 02110, the principal sum of
________________ Dollars (or such lesser amount as shall equal the aggregate
unpaid principal amount of the Three-Year Facility Revolving Credit Loans made
by the Lender to the Company under the Credit Agreement), in lawful money of the
United States of America and in immediately available funds, on the dates and in
the principal amounts provided in the Credit Agreement, and to pay interest on
the unpaid principal amount of each such Three-Year Facility Revolving Credit
Loan, at such office, in like money and funds, for the period commencing on the
date of such Three-Year Facility Revolving Credit Loan until such Three-Year
Facility Revolving Credit Loan shall be paid in full, at the rates per annum and
on the dates provided in the Credit Agreement.

         The date, amount, Type, interest rate and duration of Interest Period
(if applicable) of each Three-Year Facility Revolving Credit Loan made by the
Lender to the Company, and each payment made on account of the principal
thereof, shall be recorded by the Lender on its books and, prior to any transfer
of this Note, endorsed by the Lender on the schedule attached hereto or any
continuation thereof, PROVIDED that the failure of the Lender to make any such
recordation or endorsement shall not affect the obligations of the Company to
make a payment when due of any amount owing under the Credit Agreement or
hereunder in respect of the Three-Year Facility Revolving Credit Loans made by
the Lender.

         This Note is one of the Three-Year Facility Revolving Credit Notes
referred to in the Amended and Restated Credit Agreement dated as of December
14, 2000 (as modified and supplemented and in effect from time to time, the
"CREDIT AGREEMENT") between the Company, the Subsidiary Guarantors party
thereto, the Lenders party thereto and Fleet National Bank, as Administrative
Agent, ABN AMRO Bank N.V., as Syndication Agent, and First Union National Bank,
as Documentation Agent, and evidences Three-Year Facility Revolving Credit Loans
made by the Lender thereunder. Terms used but not defined in this Note have the
respective meanings assigned to them in the Credit Agreement.

         The Credit Agreement provides for the acceleration of the maturity of
this Note upon the occurrence of certain events and for prepayments of Loans
upon the terms and conditions specified therein.

         Except as permitted by Section 12.7 of the Credit Agreement, this Note
may not be assigned by the Lender to any other Person.

                                       A-1


         This Note shall be deemed to be an instrument under seal governed by,
and construed in accordance with, the law of The Commonwealth of Massachusetts.

ATTEST:                                   GENZYME CORPORATION

__________________________________        By:_______________________________
                                             Title:

                                       A-2





         SCHEDULE OF THREE-YEAR FACILITY REVOLVING CREDIT LOANS


         This Note evidences Three-Year Facility Revolving Credit Loans made,
Continued or Converted under the within-described Credit Agreement to the
Company, on the dates, in the principal amounts, of the Types, bearing interest
at the rates and having Interest Periods (if applicable) of the durations set
forth below, subject to the payments, Continuations, Conversions and prepayments
of principal set forth below:



- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------
                                                                                Amount
      Date                                                                       Paid,
     Made,                                                                     Prepaid,
  Continued or      Principal                                  Duration of     Continued       Unpaid
   Converted        Amount of    Type of Loan  Interest Rate    Interest          or          Principal      Notation
                      Loan                                       Period        Converted       Amount         Made By
                                                                                      
- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------


                                       A-3





                                                             EXHIBIT B

              [Form of 364-Day Facility Revolving Credit Note]

                                 PROMISSORY NOTE
                               (364-Day Facility)
$______________                                               December 14, 2000
                                                          Boston, Massachusetts

         FOR VALUE RECEIVED, GENZYME CORPORATION, a Massachusetts corporation
(the "COMPANY"), hereby promises to pay to _______________ (the "LENDER"), for
account of its respective Applicable Lending Offices provided for by the Credit
Agreement referred to below, at the principal office of Fleet National Bank, 100
Federal Street, Boston, Massachusetts 02110, the principal sum of
________________ Dollars (or such lesser amount as shall equal the aggregate
unpaid principal amount of the 364-Day Facility Revolving Credit Loans made by
the Lender to the Company under the Credit Agreement), in lawful money of the
United States of America and in immediately available funds, on the dates and in
the principal amounts provided in the Credit Agreement, and to pay interest on
the unpaid principal amount of each such 364-Day Facility Revolving Credit Loan,
at such office, in like money and funds, for the period commencing on the date
of such 364-Day Facility Revolving Credit Loan until such 364-Day Facility
Revolving Credit Loan shall be paid in full, at the rates per annum and on the
dates provided in the Credit Agreement.

         The date, amount, Type, interest rate and duration of Interest Period
(if applicable) of each 364-Day Facility Revolving Credit Loan made by the
Lender to the Company, and each payment made on account of the principal
thereof, shall be recorded by the Lender on its books and, prior to any transfer
of this Note, endorsed by the Lender on the schedule attached hereto or any
continuation thereof, PROVIDED that the failure of the Lender to make any such
recordation or endorsement shall not affect the obligations of the Company to
make a payment when due of any amount owing under the Credit Agreement or
hereunder in respect of the 364-Day Facility Revolving Credit Loans made by the
Lender.

         This Note is one of the 364-Day Facility Revolving Credit Notes
referred to in the Amended and Restated Credit Agreement dated as of December
14, 2000 (as modified and supplemented and in effect from time to time, the
"CREDIT AGREEMENT") between the Company, the Subsidiary Guarantors party
thereto, the Lenders party thereto and Fleet National Bank, as Administrative
Agent, ABN AMRO Bank N.V., as Syndication Agent, and First Union National Bank,
as Documentation Agent, and evidences 364-Day Facility Revolving Credit Loans
made by the Lender thereunder. Terms used but not defined in this Note have the
respective meanings assigned to them in the Credit Agreement.

         The Credit Agreement provides for the acceleration of the maturity of
this Note upon the occurrence of certain events and for prepayments of Loans
upon the terms and conditions specified therein.

         Except as permitted by Section 12.7 of the Credit Agreement, this Note
may not be assigned by the Lender to any other Person.

                                       B-1


         This Note shall be deemed to be an instrument under seal governed by,
and construed in accordance with, the law of The Commonwealth of Massachusetts.

ATTEST:                                   GENZYME CORPORATION

__________________________________        By:_______________________________
                                             Title:

                                       B-2





               SCHEDULE OF 364-DAY FACILITY REVOLVING CREDIT LOANS


         This Note evidences 364-Day Facility Revolving Credit Loans made,
Continued or Converted under the within-described Credit Agreement to the
Company, on the dates, in the principal amounts, of the Types, bearing interest
at the rates and having Interest Periods (if applicable) of the durations set
forth below, subject to the payments, Continuations, Conversions and prepayments
of principal set forth below:



- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------
                                                                                Amount
     Date                                                                       Paid,
     Made,                                                                     Prepaid,
  Continued or      Principal                                  Duration of     Continued       Unpaid
   Converted        Amount of    Type of Loan  Interest Rate    Interest          or          Principal      Notation
                      Loan                                       Period        Converted       Amount         Made By
                                                                                      
- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------

- ----------------- -------------- ------------- -------------- -------------- -------------- -------------- --------------


                                       B-3




C-4

                                    EXHIBIT C

                                  LEGAL OPINION


                     [For Letterhead of Palmer & Dodge, LLP]



TELEPHONE: (617) 573-0100                             FACSIMILE: (617) 227-4420

                                December 14, 2000


Fleet National Bank, as Administrative Agent
   for the Lenders (as defined below)
One Federal Street
Boston, Massachusetts 02110

ABN AMRO Bank N.V., as
  Syndication Agent for the Lenders
One Post Office Square, 39th Floor
Boston, MA 02109



First Union National Bank, as Documentation
  Agent for the Lenders
[Address]

         and

The Lenders that are parties to the
   Credit Agreement (as defined below)

Ladies and Gentlemen:

         We have acted as counsel to Genzyme Corporation, a Massachusetts
corporation (the "COMPANY"), the Company's subsidiaries who are parties to the
Credit Agreement described herein (the "SUBSIDIARY GUARANTORS") and Genzyme
Securities Corporation, a Massachusetts corporation ("GSC"), in connection with
the preparation, execution and delivery of the following documents (the "LOAN
DOCUMENTS") each dated of even date herewith: (i) the Amended and Restated
Credit Agreement (the "CREDIT AGREEMENT") between the Company, the Subsidiary
Guarantors, the lenders thereunder (the "LENDERS"), Fleet National Bank as
Administrative Agent (the "ADMINISTRATIVE AGENT"), ABN AMRO Bank N.V., as
Syndication Agent (the "SYNDICATION AGENT") and First Union National Bank as
Documentation Agent (the "DOCUMENTATION AGENT," and together with the
Administrative Agent, the "AGENTS"), (ii) the Revolving Credit Notes payable to
the order of the Lenders in the original aggregate principal amount of
$500,000,000 and (iii) the Pledge Agreement between the Company and the

                                       C-1


Administrative Agent. All capitalized terms used herein and not defined herein
shall have the meanings ascribed to them in the Credit Agreement.

         We have examined such documents and made such other investigation as we
have deemed appropriate to render the opinions set forth below. As to matters of
fact material to our opinions, we have relied, without independent verification,
on representations made in the Loan Documents and certificates and other
inquiries of officers of the Company, the Subsidiary Guarantors and GSC. We have
also relied on certificates of public officials.

         The opinions expressed herein with respect to the enforceability of the
Loan Documents are subject to (x) general principles of equity including without
limitation an implied covenant of good faith and fair dealing and (y)
bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium or
similar laws of general application affecting the rights and remedies of
creditors heretofore or hereafter enacted to the extent that the same may be
constitutionally applied. In addition, we express no opinion with respect to any
provision of the Loan Documents to the extent it provides for (i) recourse or
exercise of any remedial rights in the absence of notice and a hearing, (ii)
waivers of legal rights to the extent such waivers are against public policy,
(iii) the grant of powers of attorney, (iv) any exculpation or indemnification
that are against public policy, (v) the payment of interest in certain
circumstances at a rate which exceeds the rate of interest otherwise payable
thereunder if such increase is deemed to constitute a penalty, or (vi) your
rights of set off against the Company's deposit accounts to the extent that (a)
the funds on deposit in said accounts have been accepted by you with an intent
to apply such funds to a pre-existing claim rather than to hold the funds
subject to withdrawals in the ordinary course, (b) the funds on deposit in said
accounts are in any manner special accounts, which by the express terms on which
they are created, are made subject to the rights of a third party, or (c) you or
any other person is entitled to exercise rights of set-off or similar rights
with respect to accounts at any other institution or without notice to the
Company or the Subsidiary Guarantors or other than in accordance with applicable
law.

         Our opinion as to the enforceability of the Pledge Agreement does not
constitute an opinion as to the perfection of a security interest in the capital
stock of GSC, as to which our opinion is given in paragraph 8 hereof. Our
opinion as to the security interest in the capital stock of GSC does not include
any opinion as to the perfection of any security interest in proceeds of such
capital stock or in any distribution with respect thereto or, except as stated
in paragraph 8 hereof, as to the priority of the security interest in such
capital stock.

         This opinion is limited to the laws of The Commonwealth of
Massachusetts, the Delaware General Corporation Law and the Federal laws of the
United States. References to "our knowledge" or equivalent words mean the actual
knowledge of the lawyers in this firm responsible for preparing this opinion
after such inquiry as they deemed appropriate.

         Based on and subject to the foregoing, we are of the opinion as
follows:

         1. Each of the Company and the Subsidiary Guarantors is a corporation
validly existing and in good corporate standing under the laws of the state of
its incorporation and has the corporate power and authority to carry on its
businesses as now conducted, to own and operate its properties in connection
therewith and to enter into and perform its obligations under the Loan
Documents.

                                       C-2


         2. GSC is a corporation validly existing and in good corporate standing
under the laws of The Commonwealth of Massachusetts and has the corporate power
and authority to carry on its business as now conducted and to own and operate
its properties in connection therewith.

         3. The Loan Documents to which the Company or the Subsidiary Guarantors
are a party have been duly authorized by all necessary corporate action on the
part of the Company and each of the Subsidiary Guarantors, have been duly
executed and delivered by the Company and each of the Subsidiary Guarantors and
constitute the valid and binding obligations of the Company and each of the
Subsidiary Guarantors, enforceable against the Company and each of the
Subsidiary Guarantors, respectively, in accordance with their terms.

         4. The execution, delivery and performance of the Loan Documents will
not violate, constitute a default or breach or result in the creation of a lien
under (i) the articles of organization or certificate of incorporation, as the
case may be, or by-laws of the Company or any of the Subsidiary Guarantors; or
(ii) any agreement or instrument listed as an exhibit to the Company's Annual
Report on Form 10-K for the year ended December 31, 1999, or to any report filed
with the Securities and Exchange Commission subsequent thereto; or (iii), to our
knowledge, any judgment, decree, order, statute or government rule or regulation
applicable to the Company or any of the Subsidiary Guarantors.

         5. No approval, authorization or other action by, or filing with, any
governmental authority is required to be obtained by the Company or the
Subsidiary Guarantors in connection with the execution and delivery of the Loan
Documents by the Company or any of the Subsidiary Guarantors.

         6. To our knowledge, there is no action, proceeding or investigation
pending or threatened in writing against the Company or any of the Subsidiary
Guarantors which questions the validity of the Loan Documents or any action
taken or to be taken pursuant to the Loan Documents.

         7. The authorized capital stock of GSC consists of 200,000 shares of
common stock, par value $.01 per share, of which 100 shares (the "SHARES") are
duly and validly issued and outstanding, fully paid and nonassessable. All of
the Shares are owned of record by the Company. To our knowledge, GSC has no
options, warrants or rights outstanding and is not a party to any agreements
that obligate it to issue additional shares of its capital stock. There are no
restrictions on transfer applicable to the Shares under the articles of
organization or by-laws of GSC or, to our knowledge, any agreement or instrument
listed as an exhibit to the Company's Annual Report on Form 10-K for the year
ended December 31, 1999, or to any report filed with the Securities and Exchange
Commission subsequent thereto. We note, however, that the Shares have not been
registered under the Securities Act of 1933 and may be transferred only in
compliance with the registration requirements of such Act or an exemption
therefrom.

         8. The Pledge Agreement, together with delivery to the Administrative
Agent of the certificates representing the Shares, creates a perfected security
interest in the Shares in favor of the Administrative Agent for the benefit of
the Lenders and the Agents. Assuming the Agents and the Lenders acquired their
respective interests in good faith and without notice of any

                                       C-3


adverse claims and that such certificates are in registered form, issued or
indorsed to the Administrative Agent or in blank, the Lenders and the Agents
will have acquired the security interest in the Shares free of adverse claims.

         9. Neither the Company nor any of the Subsidiary Guarantors is an
"investment company" or a company "controlled" by an "investment company" as
defined by the Investment Company Act of 1940, as amended.

         10. Neither the Company nor any of the Subsidiary Guarantors is (i) a
"holding company," an "affiliate" of a "holding company" or a "subsidiary
company" of a "holding company" as defined by the Public Utility Holding Company
Act of 1935, as amended, or (ii) an "electric company" as defined by
Massachusetts General Laws, Chapter 164, as amended.

         This opinion shall be interpreted in accordance with the Legal Opinion
Principles issued by the Committee on Legal Opinions of the American Bar
Association's Business Law Section as published in 53 Business Lawyer 831 (May
1998).

         This opinion is furnished by us pursuant to Section 7.1(d) of the
Credit Agreement for the sole benefit of the Lenders and the Agents (including
any Persons who may be successors of the Lenders or the Agents or who may
participate with the Lenders as provided in Section 12.7 of the Credit
Agreement) and their respective counsel, and may not be used or relied upon by
any other Person or in connection with any other transaction without our prior
written consent.

                                                              Very truly yours,



                                                              Palmer & Dodge LLP


                                       C-4




               EXHIBIT D TO AMENDED AND RESTATED CREDIT AGREEMENT

                         FORM OF COMPLIANCE CERTIFICATE

                             COMPLIANCE CERTIFICATE


         This Compliance Certificate is provided pursuant to Section 9.1(c) of
that certain Amended and Restated Credit Agreement (the "Agreement") dated as of
December 14, 2000, between Genzyme Corporation ("Company"), the Subsidiary
Guarantors party thereto, the Lenders party thereto and Fleet National Bank
("Administrative Agent"), ABN AMRO Bank N.V. ("Syndication Agent") and First
Union National Bank ("Documentation Agent"). The capitalized terms used herein
shall have the meanings ascribed to such terms in the Agreement. The undersigned
hereby certifies as follows as of this date:

         1.       The representations and warranties made by the Company in the
Agreement and by the Company and each Obligor in each certificate, document or
financial or other statement furnished under or in connection therewith are true
and accurate in all material respects.

         2.       The financial information and calculations shown on the
attached Schedule A are true and accurate as of the date hereof and the
Company is in compliance with the financial covenants set forth in Section
9.9 of the Agreement.

         3.       No Default or Event of Default under the Agreement has
occurred.

         IN WITNESS WHEREOF, this Certificate has been duly executed and
delivered as a sealed instrument at Boston, Massachusetts on this ____ day of
________, ____.

                                  GENZYME CORPORATION


                                  By:
                                      -----------------------------------------
                                      Name:
                                           ------------------------------------
                                      Title:
                                            -----------------------------------

                                       D-1




                                   SCHEDULE A
                                  TO EXHIBIT D


SECTION 9.9(a)  CONSOLIDATED QUICK RATIO

cash -- $__________

Cash Equivalents -- $___________

Marketable Investments -- $____________

Accounts Receivable -- $___________

Current Liabilities -- $____________

Current Synthetic Lease Obligations -- $____________

Actual Ratio -- ____________

Minimum Ratio -- 1.50 to 1.00

SECTION 9.9(b)  CONSOLIDATED FIXED CHARGE COVERAGE RATIO

Consolidated EBITDA -- $___________

Capital Expenditures:

         Actual Capital Expenditures --                            $____________

    LESS  Capital Expenditures with respect to designated project
    ----  for improvements to new leased headquarters (the
          aggregate of such exclusions for this quarter and
          PRIOR QUARTERS DOES NOT EXCEED $12,000,000)             --$___________

          Capital Expenditures for purposes of Section 9.9(b) --  $____________

Taxes -- $___________

Dividend Payments -- $___________

Synthetic Lease Obligations -- $___________

Interest Expense -- $___________

Synthetic Lease Obligations -- $___________

                                       D-2



Actual Ratio -- ___________

Minimum Ratio -- 3.00 to 1.00

SECTION 9.9(c)  CONSOLIDATED LEVERAGE RATIO

Consolidated Funded Debt -- $_________

Unrestricted Cash and Marketable Investments in excess of $125,000,000 -- $_____

Consolidated EBITDA -- $___________

Actual Ratio -- ___________

Maximum Ratio -- 2.00 to 1.00

LEVEL CALCULATION

CONSOLIDATED DEBT COVERAGE RATIO

cash -- $__________

Cash Equivalents -- $__________

Marketable Investments -- $__________

Consolidated Funded Debt -- $__________

Ratio -- __________

SENIOR UNSECURED DEBT RATING -- _________(written confirmation is attached)

Level Period (I, II, III or IV) for Applicable Margin and Applicable Commitment
Fee determination: __________________


                                       D-3


                                                                      EXHIBIT E


                           [Form of Joinder Agreement]


         This Joinder Agreement is delivered pursuant to Section 9.13 of the
Amended and Restated Credit Agreement dated as of December 14, 2000 (the "CREDIT
AGREEMENT") between Genzyme Corporation (the "COMPANY"), the Subsidiary
Guarantors party thereto, the Lenders party thereto, and Fleet National Bank, as
Administrative Agent, ABN AMRO Bank N.V., as Syndication Agent, and First Union
National Bank, as Documentation Agent.

         The undersigned hereby agrees to become a "Subsidiary Guarantor" as
such term is used in the Credit Agreement and, by virtue of its execution and
delivery of this Joinder Agreement, agrees to assume all of the obligations and
liabilities of a Subsidiary Guarantor under the Credit Agreement and the other
Loan Documents.

         IN WITNESS WHEREOF, the undersigned has caused this Joinder Agreement
to be duly executed on this _____ day of _____________, _____.


                                [NAME OF SUBSIDIARY]


                                By:
                                   ------------------------------------------
                                   Title:


                                Address for Notices:

                                [Address]


                                       E-1




                                                                      EXHIBIT F

                         [Form of Notice of Assignment]

                              NOTICE OF ASSIGNMENT


                                                  [Date]


Genzyme Corporation
One Mountain Road
Framingham, Massachusetts 01701
Attention:  Mr. Evan M. Lebson, Treasurer

Fleet National Bank,
  as Administrative Agent
One Federal Street
Boston, Massachusetts 02110
Attention:  High Tech Group

         Re:      Amended and Restated Credit Agreement dated as of December 14,
                  2000 (the "CREDIT AGREEMENT"), between Genzyme Corporation
                  (the "COMPANY"), the Subsidiary Guarantors party thereto, the
                  Lenders party thereto and Fleet National Bank, as
                  Administrative Agent, ABN AMRO Bank N.V., as Syndication
                  Agent and First Union National Bank, as Documentation Agent

Ladies and Gentlemen:

         We hereby give notice that, effective as of the date hereof, [Name of
Assignor] (the "ASSIGNOR") has assigned its rights and obligations with respect
to _____% of its outstanding Revolving Credit Commitment (representing
$__________ of the Assignor's outstanding Revolving Credit Commitment and
Revolving Credit Loans, of which $____________ consists of the Assignor's
outstanding 364-Day Revolving Credit Commitment and $___________ consists of the
Assignor's outstanding Three-Year Revolving Credit Commitment (such interest in
such rights and obligations being hereinafter referred to as the "ASSIGNED
INTEREST") under the Credit Agreement to [Name of Assignee] (the "ASSIGNEE").
The Assignee hereby agrees (a) to become a "Lender" pursuant to Section 12.7(b)
of the Credit Agreement (if not already a Lender under the Credit Agreement) and
(b) to assume all the obligations of the Assignor thereunder with respect to the
Assigned Interest.

         The address for notices, Applicable Lender Office(s) and payment
instructions for the Assignee are as follows:

                           Address for Notices:

                           ------------------------
                           ------------------------

                                       F-1


                           ------------------------

                           Attention:
                           Telephone:
                           Telecopier:

                           Lending Office for Prime Rate
                           Loans and LIBOR Loans:

                           ------------------------
                           ------------------------
                           ------------------------

                           Payment Instructions:

                           ------------------------
                           ------------------------
                           ------------------------

         Please sign and return the enclosed copy of this letter to the
undersigned to indicate your receipt hereof, and your consent to or notice of
(as applicable) the above-mentioned assignment and assumption, and your
agreement to the release of the Assignor from its obligations under the Credit
Agreement with respect to the Assigned Interest. As a condition to the
effectiveness of the above-mentioned assignment and assumption, the Assignee
hereby agrees to pay to the Administrative Agent on the date hereof an
assignment fee of $4,500.

                                         Very truly yours,

                                         [NAME OF ASSIGNOR]


                                         By:
                                            --------------------------------
                                              Title


                                         [NAME OF ASSIGNEE]


                                         By:
                                            --------------------------------
                                              Title

ACKNOWLEDGED OR CONSENTED TO
  (AS APPLICABLE):

GENZYME CORPORATION

                                       F-2


By:
   -----------------------------------------
     Title:


FLEET NATIONAL BANK,
  as Administrative Agent


By:
   -----------------------------------------
     Title:

                                       F-3



                                    EXHIBIT G

                                PLEDGE AGREEMENT

         PLEDGE AGREEMENT (this "AGREEMENT"), dated as of December 14, 2000, by
GENZYME CORPORATION ("COMPANY"), a Massachusetts corporation, to FLEET NATIONAL
BANK, as Administrative Agent, for the Lenders (as defined below) (in such
capacity, together with its successors in such capacity, the "Administrative
Agent").


                              W I T N E S S E T H :
                              - - - - - - - - - -

         WHEREAS, the Company, certain obligors (the "Obligors"), the
Administrative Agent, ABN AMRO Bank N.V., as Syndication Agent, First Union
National Bank, as Documentation Agent, and certain lenders (the "Lenders") are
parties to an Amended and Restated Credit Agreement of even date (as amended,
supplemented or otherwise modified from time to time, the "CREDIT AGREEMENT";
capitalized terms used but not otherwise defined shall have the meanings
ascribed to such terms in the Credit Agreement), pursuant to which the Lenders
have agreed to make up to $500,000,000 in Revolving Credit Loans to the Company
on the terms and subject to the conditions set forth therein;


         WHEREAS, to induce to the Lenders to enter into the Credit Agreement
and make the Revolving Credit Loans thereunder, the Company has agreed to enter
into this Pledge Agreement and pledge all of the capital stock of Genzyme
Securities Corporation (the "Subsidiary") a Massachusetts corporation, to the
Administrative Agent, as agent for the Lenders;


         NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Company and the Administrative Agent hereby agree as follows:


         SECTION 1. PLEDGE. The Company hereby grants, assigns and pledges to
the Administrative Agent, for the benefit of each of the Lenders and Agents, a
valid lien on and security interest in, all of the Company's right, title and
interest in and to the following, whether now owned or at any time hereafter
acquired (collectively, the "Collateral"):

                  (a) All of the issued and outstanding capital stock of the
Company in the Subsidiary as set forth on Schedule 1 (the "Pledged Shares") and
the certificates representing the Pledged Shares, and all dividends,
distributions, cash, instruments, investment property and other property from
time to time received, receivable or otherwise distributed in respect of or in
exchange for any or all of the Pledged Shares, and all additional capital stock
in Subsidiary from time to time acquired in any manner by the Company, and the
certificates representing such additional capital stock, and all dividends,
distributions, cash, instruments, investment


                                      G-1


property and other property from time to time received, receivable or
otherwise distributed in respect of or in exchange for any or all of such
capital stock; and

                  (b) all proceeds of any of the foregoing (including, without
limitation, proceeds constituting any property of the types described above).

         SECTION 2. ALL OBLIGATIONS SECURED. This Agreement secures the prompt
and complete payment and performance when due (whether at the stated maturity,
by acceleration or otherwise) of all of the Obligations.

         SECTION 3. REPRESENTATIONS AND WARRANTIES. Company represents and
warrants as follows:


                  (a) Company has the requisite corporate power and authority to
execute, deliver and perform this Agreement and all corporate action necessary
for the execution, delivery and performance of this Agreement has been taken.

                  (b) The execution, delivery and performance of this Agreement
by Company does not, and will not, contravene (i) the Articles of Organization
and By-Laws of Company, (ii) any legal requirement or (iii) any franchise,
license, permit, indenture, contract, lease, agreement, instrument or other
commitment to which it is a party or by which it or any of its properties are
bound, and will not, except as contemplated herein, result in the imposition of
any liens or security interests upon any of its properties.

                  (c) This Agreement is the legal, valid and binding obligation
of Company, enforceable in accordance with its terms.

                  (d) Company is the legal and beneficial owner of record of the
Pledged Shares set forth opposite Company's name in Schedule 1, free and clear
of any lien other than liens created pursuant to this Agreement. On the date
hereof, no effective financing statement or other instrument similar in effect
covering all or any part of the Collateral will be on file in any recording
office.

                  (e) The pledge of the Collateral and granting of the liens
hereunder, together with the delivery of the stock certificates pledged
hereunder and appropriate filings of Uniform Commercial Code financing
statements, create a valid and perfected first priority lien on the Collateral,
securing the payment and performance of the Obligations, and all filings and
other actions necessary or desirable to perfect and protect such lien have been
duly made or taken.

                  (f) No authorization, approval, or other action by, and no
notice to or filing with, any Person or governmental authority is required for
(i) the pledge by such Company of the Collateral pursuant to this Agreement, the
grant by such Company of the liens granted hereby or the execution, delivery or
performance of this Agreement by such Company, (ii) the perfection of the liens
granted pursuant to this Agreement, except for the delivery to the
Administrative Agent of the stock certificates representing the Pledged Shares
in Subsidiary and appropriate filings of Uniform Commercial Code financing
statements, or (iii) the exercise by the Administrative Agent of the rights or
remedies provided for in this Agreement.


                                      G-2


                  (g) The Pledged Shares represented by the certificates
identified in Schedule 1 are, and all other Pledged Shares in which Company
shall hereafter obtain an interest will be duly authorized, fully paid and
nonassessable and none of such Pledged Shares is or will be subject to any
contractual restriction upon the transfer of such Pledged Shares.

                  (h) The Pledged Shares represented by the certificates
identified in Schedule 1 constitute all of the issued and outstanding shares of
capital stock or other equity securities of any class in the Subsidiary, and
Schedule 1 correctly identifies, as at the date hereof, the respective class of
the shares comprising such Pledged Shares and the respective number of shares
represented by each such certificate.

         SECTION 4. FURTHER ASSURANCES; COVENANTS; REPLACEMENT COLLATERAL.

                  (a) Company covenants and agrees that at any time and from
time to time, at the expense of Company, Company will promptly execute and
deliver all further instruments and documents, and take all further action, that
may be necessary or desirable, or that the Administrative Agent may request, to
perfect and protect any security interest granted or purported to be granted
hereby or to enable the Administrative Agent to exercise and enforce its rights
and remedies hereunder with respect to any Collateral. Without limiting the
generality of the foregoing, Company will execute and file such financing or
continuation statements, or amendments thereto, and such other instruments or
notices, as may be necessary or desirable, or as the Administrative Agent may
request, to perfect and preserve the liens granted or purported to be granted
hereby, and cause third parties to acknowledge and to register the pledge of
securities hereunder on their books and to deliver statements of account upon
the Administrative Agent's request therefor.

                  (b) Company covenants and agrees that, without the prior
written consent of the Administrative Agent and the Lenders, Company will not
(i) sell, assign (by operation of law or otherwise) or otherwise dispose of, or
grant any option with respect to, any of the Collateral, (ii) create or suffer
to exist any lien upon or with respect to any of the Collateral, except for the
liens under this Agreement, (iii) vote to enable, or take any other action to
permit, Subsidiary to issue any capital stock or other equity securities of any
nature or to issue any other securities convertible into, exchangeable for or
granting the right to purchase any capital stock or other equity securities of
any nature of Subsidiary or to convey, exchange, lease, assign, transfer, sell
or otherwise dispose of any material assets of the Subsidiary, (iv) enter into
any agreement or undertaking restricting the right or ability of the
Administrative Agent to sell, assign or transfer any of the Collateral or (v)
permit Subsidiary to issue any shares of capital stock or other equity
securities of any nature or to issue any securities convertible into or granting
the right to purchase or otherwise acquire any shares of capital stock or equity
securities of Subsidiary or to convey, exchange, lease, assign, transfer, sell
or otherwise dispose of any material assets of the Subsidiary.

                  (c) If Company acquires any additional capital stock in
Subsidiary, Company shall hold the same in trust for the Administrative Agent
and promptly deliver to the Administrative Agent the stock certificates
evidencing such capital stock, together with undated stock powers related
thereto duly executed in blank by Company.


                                      G-3


         SECTION 5. RIGHTS OF THE COMPANY; VOTING; ETC.

                  (a) So long as no Event of Default shall have occurred and be
continuing, Company shall be entitled to exercise any and all voting and other
consensual rights pertaining to the Collateral or any part thereof for any
purpose not inconsistent with the terms of this Agreement and the other Loan
Documents and in a manner which does not impair any of the Collateral and to
receive and retain any and all cash dividends and distributions paid in respect
of the Pledged Shares.

                  (b)      Upon the occurrence and during the continuance of an
Event of Default:

                           (i) All rights of any Company to receive the cash
                  dividends and distributions that such Company would otherwise
                  be authorized to receive and retain pursuant to Section 5(a)
                  hereof shall cease, and all such rights shall thereupon become
                  vested in the Administrative Agent who shall thereupon have
                  the sole right to receive and hold as Collateral such
                  dividends, distributions and payments.

                           (ii) Any and all other dividends and distributions
                  payable to any Company in respect of the Collateral shall be
                  received by such Company in trust for the benefit of the
                  Administrative Agent, shall be segregated from other funds of
                  such Company and shall be forthwith paid over to the Lender as
                  Collateral in the same form as so received (with any necessary
                  endorsement).

         SECTION 6. PRINCIPAL PLACE OF BUSINESS; RECORDS. Company shall keep its
principal place of business and the place where it keeps its records concerning
the Collateral at the address of the Company specified in the Credit Agreement.
The Company will hold and preserve such records and, upon reasonable notice from
the Administrative Agent, will permit representatives of the Lender at any time
during normal business hours to inspect and make abstracts from such records.

         SECTION 7. TRANSFER OR LIENS. Company agrees that it will not sell,
transfer or convey any interest in, grant any option with respect to, or suffer
or permit any lien to be created upon or with respect to, any of the Pledged
Shares during the term of this Agreement, except to or in favor of the
Administrative Agent.

         SECTION 8. ADMINISTRATIVE AGENT APPOINTED ATTORNEY-IN-FACT; IRREVOCABLE
AUTHORIZATION AND INSTRUCTION TO THE SUBSIDIARIES. Company hereby appoints the
Administrative Agent as Company's attorney-in-fact, with full authority in the
place and stead of the Company and in the name of the Company or otherwise, from
time to time in the Lender's discretion, to, upon the occurrence and during the
continuance of an Event of Default, take any action and to execute any
instrument which the Administrative Agent may deem necessary or advisable to
accomplish the purposes of this Agreement, including, without limitation, to
exercise the voting and other consensual rights which Company would otherwise be
entitled to exercise pursuant to Section 5(a) (and all right of Company to
exercise such rights shall cease) and to receive, endorse and collect all
instruments made payable to the Company representing any distribution


                                      G-4


in respect of the Collateral or any part thereof and to give full discharge
for the same. Company hereby authorizes and instructs Subsidiary to comply
with any instruction received by it from the Lender in writing that (i)
states that an Event of Default has occurred and is continuing and (ii) is
otherwise in accordance with the terms of this Agreement, without any other
or further instructions from Company, and Company agrees that Subsidiary
shall be fully protected in so complying. Company hereby ratifies all that
such attorney shall lawfully do or cause to be done by virtue hereof. This
power of attorney is coupled with an interest and is irrevocable.

         SECTION 9.        REASONABLE CARE; RETURN OF COLLATERAL.

                  (a) Prior to the exercise of its remedies hereunder, the
Administrative Agent shall be deemed to have exercised reasonable care in the
custody and preservation of the Collateral in its possession if the Collateral
is accorded treatment substantially equal to that which the Lender accords its
own similar property, it being understood that the Administrative Agent shall
not have the responsibility under this Agreement for taking any necessary steps
to preserve rights against any parties with respect to any Collateral except as
set forth in subsection (b) below.

                  (b) Upon the indefeasible payment in full in cash of all the
Obligations and the termination of the Credit Agreement, Company shall be
entitled to the return of all of the Collateral pledged by Company hereunder.

         SECTION 10. ADMINISTRATIVE AGENT MAY PERFORM. If Company fails to
perform any agreement contained herein, the Administrative Agent may itself
perform, or cause performance of, such agreement, and the expenses of the
Administrative Agent incurred in connection therewith shall be payable by such
Company.

         SECTION 11. REMEDIES UPON DEFAULT. If any Event of Default shall have
occurred and be continuing, the Administrative Agent may exercise in respect of
the Collateral, in addition to other rights and remedies provided for herein or
otherwise available to it, all the rights and remedies of a secured party under
the Uniform Commercial Code (the "CODE") and the Administrative Agent may also,
without notice except as specified below, transfer the Collateral into its name
or that of its nominee, sell the Collateral or any part thereof in one or more
parcels at public or private sale, at any exchange, broker's board or at any of
the Administrative Agent's offices or elsewhere, for cash, on credit or for
future delivery, and upon such other terms as the Administrative Agent may deem
commercially reasonable. Company agrees that, to the extent notice of sale shall
be required by law, at least ten days' notice to Company of the time and place
of any public sale or the time after which any private sale is to be made shall
constitute reasonable notification. The Administrative Agent shall not be
obligated to make any sale of Collateral regardless of notice of sale having
been given. The Administrative Agent may adjourn any public or private sale from
time to time by announcement at the time and place fixed therefor, and such sale
may, without further notice, be made at the time and place to which it was so
adjourned.

         SECTION 12. INDEMNITY AND EXPENSES.


                                      G-5


                  (a) Company agrees to and hereby indemnifies the
Administrative Agent, each other Agent and each Lender from and against any and
all claims, damages, losses, liabilities and expenses arising out of, or in
connection with, or resulting from, this Agreement (including, without
limitation, enforcement of this Agreement) other than such as arise from the
Administrative Agent's gross negligence or willful misconduct.

                  (b) Company will, upon demand, pay to the Administrative Agent
the amount of any and all expenses, including the reasonable fees and expenses
of its counsel and of any experts and agents, that the Administrative Agent may
incur in connection with (i) the administration of this Agreement, (ii) the
custody or preservation of, or the sale of, collection from, or other
realization upon, any of the Collateral, (iii) the exercise or enforcement of
any of the rights of the Administrative Agent hereunder, (iv) the failure of
Company to perform or observe any of the provisions hereof, or (v) any action
taken by the Lender pursuant to this Agreement.

         SECTION 13. SECURITY INTEREST ABSOLUTE. All rights of the
Administrative Agent and security interests hereunder, and all obligations of
Company hereunder, shall be absolute and unconditional irrespective of:

                  (a)      any lack of validity or enforceability of the Credit
Agreement, the Note or any other Loan Document;

                  (b)      any change in the time, manner or place of payment
of, or in any other term of, all or any of the Obligations, or any other
amendment or waiver of or any consent to departure from any of the Loan
Documents;

                  (c)      any taking and holding of collateral or any guaranty
for all or any of the Obligations, or any amendment, alteration, exchange,
substitution, transfer, enforcement, waiver, subordination, termination or
release of any collateral or such guaranty, or any non-perfection of any
collateral, or any consent to departure from any such guaranty;

                  (d)      any manner of application of collateral, or proceeds
thereof, to all or any of the Obligations, or the manner of sale of any
collateral;

                  (e)      any consent by any Agent or any Lender to the
restructure of the Obligations, or any other restructure or refinancing of the
Obligations or any portion thereof;

                  (f) any modification, compromise, settlement or release by any
Agent or any Lender, by operation of law or otherwise, collection or other
liquidation of the Obligations or the liability of any guarantor, or of any
collateral, in whole or in part, and any refusal of payment by any Agent or any
Lender, in whole or in part, from any obligor or guarantor in connection with
any of the Obligations, whether or not with notice to, or further assent by, or
any reservation of rights against, any Company; or

                  (g) any other circumstance (including, without limitation, any
statute of limitations) which might otherwise constitute a defense available to,
or a discharge of, any third party pledgor or guarantor.


                                      G-6


         SECTION 14. AMENDMENTS; WAIVERS; PARTIAL EXERCISE. No amendment or
waiver of any provision of this Agreement or consent to any departure by the
Company here from shall be effective unless in writing and signed by Company,
the Administrative Agent and the Required Lenders (or, to the extent required by
Section 12.5 of the Credit Agreement, all the Lenders), and any such amendment,
waiver or consent shall be effective only to the extent set forth therein. No
failure to exercise or any delay in exercising on the part of the Administrative
Agent any right, power or privilege under this Agreement shall operate as a
waiver thereof. No single or partial exercise of any right, power or privilege
under this Agreement shall preclude any other or further exercise thereof or the
exercise of any other right, power or privilege.

         SECTION 15. ADDRESSES FOR NOTICES. All notices and correspondence
hereunder shall be provided in the manner, to the Persons and to the addresses
set forth in the Credit Agreement.

         SECTION 16. CONTINUING SECURITY INTEREST; ASSIGNMENTS OF SECURED DEBT.
This Agreement shall create a continuing security interest in and lien on the
Collateral and shall (i) remain in full force and effect until released in
accordance with the terms hereof, (ii) be binding upon Company, its successors
and assigns, and (iii) inure, together with the rights and remedies of the
Administrative Agent and Lenders hereunder, to the benefit of their respective
successors and assigns. Without limiting the generality of the foregoing clause
(iii), the Administrative Agent or Lenders, in accordance with the terms of the
Credit Agreement, may assign or otherwise transfer all or any portion of their
rights and obligations under this Agreement to any other Person, and such other
Person shall thereupon become vested with all the benefits in respect hereof
granted herein.

         SECTION 17. GOVERNING LAW; DEFINED TERMS. This Agreement shall be
governed by and construed in accordance with the laws of the Commonwealth of
Massachusetts without giving effect to principles of conflicts of law. Unless
otherwise defined herein or in the Credit Agreement, terms used in Articles 8
and 9 of the Code are used herein as therein defined. This Agreement shall be
deemed for all purposes to be a Loan Document under the Credit Agreement.

         SECTION 18. MARSHALLING. Company hereby waives any right to require the
Administrative Agent to marshal any security or Collateral or otherwise compel
the Administrative Agent seek recourse against or satisfaction of the
Obligations from one source before seeking recourse or satisfaction from another
source.

         SECTION 19. EXECUTION IN COUNTERPARTS; TELECOPIED SIGNATURES. This
Agreement may be executed in counterparts, each of which shall constitute an
original, but all of which taken together shall constitute one and the same
instrument. This Agreement, and any notices to be given pursuant to this
Agreement, may be executed and delivered by telecopier or other facsimile
transmission all with the same force and effect as if the same was a fully
executed and delivered original counterpart.

         SECTION 20. SUBMISSION TO JURISDICTION. ALL DISPUTES AMONG THE COMPANY
AND THE ADMINISTRATIVE AGENT OR LENDERS, WHETHER


                                      G-7


SOUNDING IN CONTRACT, TORT, EQUITY OR OTHERWISE, SHALL BE RESOLVED ONLY BY
STATE AND FEDERAL COURTS LOCATED IN BOSTON, MASSACHUSETTS, AND THE COURTS TO
WHICH AN APPEAL THEREFROM MAY BE TAKEN; PROVIDED, HOWEVER, THAT THE
ADMINISTRATIVE AGENT SHALL HAVE THE RIGHT, TO THE EXTENT PERMITTED BY
APPLICABLE LAW, TO PROCEED AGAINST THE COMPANY OR ITS PROPERTY IN ANY
LOCATION REASONABLY SELECTED BY THE ADMINISTRATIVE AGENT IN GOOD FAITH TO
ENABLE THE ADMINISTRATIVE AGENT TO REALIZE ON SUCH PROPERTY, OR TO ENFORCE A
JUDGMENT OR OTHER COURT ORDER IN FAVOR OF THE LENDER. THE COMPANY AGREES THAT
IT WILL NOT ASSERT ANY PERMISSIVE COUNTERCLAIMS, SETOFFS OR CROSS-CLAIMS IN
ANY PROCEEDING BROUGHT BY THE ADMINISTRATIVE AGENT. THE COMPANY WAIVES ANY
OBJECTION THAT IT MAY HAVE TO THE LOCATION OF THE COURT IN WHICH THE
ADMINISTRATIVE AGENT HAS COMMENCED A PROCEEDING, INCLUDING, WITHOUT
LIMITATION, ANY OBJECTION TO THE LAYING OF VENUE OR BASED ON FORUM NON
CONVENIENS.

         SECTION 21. JURY TRIAL. THE COMPANY AND, BY ITS ACCEPTANCE HEREOF, THE
ADMINISTRATIVE AGENT EACH HEREBY WAIVE ANY RIGHT TO A TRIAL BY JURY.

         IN WITNESS WHEREOF, the Company has caused this Agreement to be
executed by its proper and duly authorized officer as of the day and year first
above written.


                                       GENZYME CORPORATION


                                       By:   ___________________________________
                                             Name:
                                             Title:














                                      G-8



Accepted:

FLEET NATIONAL BANK, as
Administrative Agent


By:   ________
      Name:
      Title:





















                                      G-9



                                   Schedule 1

                            Pledge Agreement between
      GENZYME CORPORATION AND FLEET NATIONAL BANK, AS ADMINISTRATIVE AGENT



PLEDGED SHARES


Issuer:  Genzyme Securities Corporation

Class of Shares:  Common

Number of Pledged Shares:  One Hundred (100)

Date of Issuance:  December 30, 1991

Date of Pledge:  December 14, 2000















                                      G-10


                                    EXHIBIT H

                               NOTICE OF BORROWING


                                                       Date: _____________, ___

Fleet National Bank,
  as Administrative Agent
One Federal Street
Boston, Massachusetts 02110
Attention:  High Tech Group

         Re:      Amended and Restated Credit Agreement dated as of December 14,
                  2000 (the "CREDIT AGREEMENT"), between Genzyme Corporation
                  (the "COMPANY"), the Subsidiary Guarantors party thereto, the
                  Lenders party thereto and Fleet National Bank, as
                  Administrative Agent, ABN AMRO Bank N.V., as Syndication
                  Agent, and First Union National Bank, as Documentation Agent

Ladies and Gentlemen:

         The undersigned, Genzyme Corporation (the "COMPANY"), refers to the
Credit Agreement, the terms defined therein being used herein as therein
defined, and hereby gives you notice irrevocably, pursuant to Section 4.5 of the
Credit Agreement, of the borrowing as a Revolving Credit Loan specified below:

         1.       The Business Day of the proposed borrowing is _______________,
                  ___________.

         2.       The aggregate amount of the proposed borrowing is $___________
                  (minimum aggregate amount equal to $5,000,000 or an integral
                  multiple of $1,000,000 in excess thereof).

         3.       $_______________ of the borrowing is requested under the
                  364-Day Facility, and $_______________ of the borrowing is
                  requested under the Three-Year Facility.

         4.       The borrowing is to be comprised of $_________ of [Prime Rate]
                  [LIBOR] Loans.

         5.       The duration of the Interest Period for the LIBOR Loans
                  included in the borrowing shall be _________ months.

The undersigned hereby certifies that the following statements are true on the
date hereof, and will be true on the date of the proposed borrowing, before and
also after giving effect thereto and to the intended use of the Loan:

         (a)      no Default has occurred and is continuing;

         (b)      the representations and warranties made by the Company in
         Section 8 of the Credit Agreement, and by each Obligor in each of the
         other Loan Documents to which it


                                      H-1


         is a party, are true and complete in all material respects on and as
         of the date of the making of such Loan with the same force and effect
         as if made on and as of such date (except with respect to any such
         representation or warranty that is expressly stated to have been made
         as of a specific date);

         (c)      such Loan will not cause the aggregate outstanding amount of
         Revolving Credit Loans to exceed the aggregate amount of the Revolving
         Credit Commitments in effect as of the time that such Loan is made;

         (d)      such Loan will not cause the aggregate outstanding amount of
         364-Day Revolving Credit Loans to exceed the aggregate amount of the
         364-Day Revolving Credit Commitments in effect as of the time that such
         Loan is made; and

         (e)      such Loan will not cause the aggregate outstanding amount of
         Three-Year Revolving Credit Loans to exceed the aggregate amount of the
         Three-Year Revolving Credit Commitments in effect as of the time that
         such Loan is made.

                              GENZYME CORPORATION

                                        By:   _____________________________

                                        Title:   __________________________















                                      H-2


                                    EXHIBIT I

                       NOTICE OF CONVERSION/CONTINUATION


                                                      Date: ______________, ____

Fleet National Bank,
  as Administrative Agent
One Federal Street
Boston, Massachusetts 02110
Attention:  High Tech Group

         Re:      Amended and Restated Credit Agreement dated as of December 14,
                  2000 (the "CREDIT AGREEMENT"), between Genzyme Corporation
                  (the "COMPANY"), the Subsidiary Guarantors party thereto, the
                  Lenders party thereto and Fleet National Bank, as
                  Administrative Agent, ABN AMRO Bank N.V., as Syndication
                  Agent, and First Union National Bank, as Documentation Agent

Ladies and Gentlemen:

         The undersigned, Genzyme Corporation (the "COMPANY"), refers to the
Credit Agreement, the terms defined therein being used herein as therein
defined, and hereby gives you notice irrevocably, pursuant to Section 4.5 of the
Credit Agreement, of the [Conversion] [Continuation] of the Loans specified
herein, that:

         1.       The Conversion/Continuation Date is _______________,________.

         2.       The aggregate amount of the Loans to be [converted]
                  [continued] is $______ (minimum aggregate amount equal to
                  $5,000,000 or an integral multiple of $1,000,000 in excess
                  thereof).

         3.       $________ of these Loans were made under the 364-Day Facility,
                  and $_________ of these Loans were made under the Three-Year
                  Facility.

         4.       The Loans are to be [converted into] [continued as] [LIBOR]
                  [Prime Rate] Loans.

         5.       [If applicable:]  The duration of the Interest Period for the
                  LIBOR Loans included in the [conversion] [continuation] shall
                  be ____ months.

         The undersigned hereby certifies that the following statements are true
on the date hereof, and will be true on the date of the proposed
[Continuation][Conversion], before and also after giving effect thereto and to
the intended use of the [Continuation][Conversion]:

         (a)      no Default has occurred and is continuing;

         (b)      the representations and warranties made by the Company in
         Section 8 of the Credit Agreement, and by each Obligor in each of the
         other Loan Documents to which it


                                      I-1


         is a party, are true and complete in all material respects on and as of
         the date of such [Conversion][Continuation] with the same force and
         effect as if made on and as of such date (except with respect to any
         such representation or warranty that is expressly stated to have been
         made as of a specific date);

         (c)      such [Conversion][Continuation] will not cause the aggregate
         outstanding amount of Revolving Credit Loans to exceed the aggregate
         amount of the Revolving Credit Commitments in effect as of the time
         that such [Conversion][Continuation] is effected;

         (d)      such [Conversion][Continuation] will not cause the aggregate
         outstanding amount of 364-Day Revolving Credit Loans to exceed the
         aggregate amount of the 364-Day Revolving Credit Commitments in effect
         as of the time that such [Conversion][Continuation] is effected; and

         (e)      such [Conversion][Continuation] will not cause the aggregate
         outstanding amount of Three-Year Revolving Credit Loans to exceed the
         aggregate amount of the Three-Year Revolving Credit Commitments in
         effect as of the time that such [Conversion][Continuation] is effected.

                              GENZYME CORPORATION

                                         By:  __________________________________

                                         Title:  _______________________________
















                                      I-2


                                    EXHIBIT J
                              NOTICE OF PREPAYMENT


                                                     Date: _______________, ___

Fleet National Bank,
  as Administrative Agent
One Federal Street
Boston, Massachusetts 02110
Attention:  High Tech Group

         Re:      Amended and Restated Credit Agreement dated as of December 14,
                  2000 (the "CREDIT AGREEMENT"), between Genzyme Corporation
                  (the "COMPANY"), the Subsidiary Guarantors party thereto, the
                  Lenders party thereto and Fleet National Bank, as
                  Administrative Agent, ABN AMRO Bank N.V., as Syndication
                  Agent, and First Union National Bank, as Documentation Agent

Ladies and Gentlemen:

         The undersigned, Genzyme Corporation (the "COMPANY"), refers to the
Credit Agreement, the terms defined therein being used herein as therein
defined, and hereby gives you notice irrevocably, pursuant to Section 4.5 of the
Credit Agreement, of the prepayment of the Loans specified herein, that:

         1.   The date of prepayment is ____________, ____.

         2.   The aggregate amount of the Loans to be prepaid is $______
              (minimum aggregate amount equal to $5,000,000 or an integral
              multiple of $1,000,000 in excess thereof).

         3.   $__________ of the Loans to be prepaid hereunder were made under
              the 364-Day Facility, and $__________ of the Loans to be prepaid
              hereunder were made under the Three-Year Facility;

         4.   The Loans to be prepaid consist of [LIBOR] [Prime Rate] Loans.

         5.   [If applicable:]  The duration of the Interest Period for the
              LIBOR Loans to be prepaid was ____ months, beginning on ________
              ___, ___.

                              GENZYME CORPORATION

                                         By:  __________________________________

                                         Title:  _______________________________








                                      J-1



                                    EXHIBIT K

                        TERMINATION OF CREDIT AGREEMENT


                                                   Date: _________________, ___

Fleet National Bank,
  as Administrative Agent
One Federal Street
Boston, Massachusetts 02110
Attention:  High Tech Group

         Re:      Credit Agreement dated as of November 12, 1999 (the "CREDIT
                  AGREEMENT"), between Genzyme Corporation (the "COMPANY"), the
                  Subsidiary Guarantors party thereto, the Lenders party thereto
                  and Fleet National Bank, as Administrative Agent, ABN AMRO
                  Bank N.V., as Syndication Agent, and Mellon Bank, N.A., as
                  Documentation Agent

Ladies and Gentlemen:

         The undersigned refer to the Credit Agreement, the terms defined
therein being used herein as therein defined, and hereby gives you notice
irrevocably, that the Credit Agreement is hereby terminated.

                                GENZYME CORPORATION
                                as the Company

                                       By:  __________________________________

                                       Title:  _______________________________

                                DEKNATEL SNOWDEN PENCER, INC.
                                as a Subsidiary Guarantor

                                       By:  __________________________________

                                       Title:  _______________________________

                                GENZYME SURGICAL PRODUCTS
                                 CORPORATION
                                as a Subsidiary Guarantor

                                       By:  __________________________________

                                       Title:  _______________________________


                                      K-1


                             ALLSTON LANDING LIMITED
                             PARTNERSHIP
                             as a Subsidiary Guarantor
                             By: Allston Landing Corporation
                                 its General Partner

                                     By:   __________________________________

                                     Title:   _______________________________

                             ABN AMRO BANK N.V.
                             as the Syndication Agent and as a Lender

                                     By:   __________________________________

                                     Title:   _______________________________

                             MELLON BANK, N.A.
                             as the Documentation Agent and as a Lender

                                     By:   __________________________________

                                     Title:   _______________________________

                             FIRST UNION NATIONAL BANK
                             as a Lender

                                     By:   __________________________________

                                     Title:   _______________________________

                             BANK OF TOKYO-MITSUBISHI
                             TRUST COMPANY
                             as a Lender

                                     By:   __________________________________

                                     Title:   _______________________________

                             THE CHASE MANHATTAN BANK
                             as a Lender

                                     By:   __________________________________

                                     Title:   _______________________________

                             CITIZENS BANK OF MASSACHUSETTS


                                      K-2


                             as a Lender
                                     By:   __________________________________

                                     Title:   _______________________________

                             AGREED AND ACCEPTED:

                             FLEET NATIONAL BANK
                             as the Administrative Agent and as a Lender
                                     By:   __________________________________

                                     Title:   _______________________________
















                                      K-3

EX-99.(D)(1)

                                                                EXHIBIT 99(d)(1)

                                                                  EXECUTION COPY

                          AGREEMENT AND PLAN OF MERGER

                                  BY AND AMONG

                               GENZYME CORPORATION

                           SWIFT STARBOARD CORPORATION

                        AND SANGSTAT MEDICAL CORPORATION

                           Dated as of August 4, 2003



                             INDEX OF DEFINED TERMS
                                                                           
Acquisition Proposal..........................................................35
Affiliates....................................................................49
Agreement......................................................................1
Assignee......................................................................51
Audit.........................................................................22
business of...................................................................49
Certificate of Merger..........................................................4
Certificates...................................................................7
Closing........................................................................5
Closing Date...................................................................5
Code..........................................................................10
Company........................................................................1
Company Authorizations........................................................16
Company Balance Sheet.........................................................15
Company Balance Sheet Date....................................................15
Company Board of Directors.....................................................1
Company Capital Stock.........................................................12
Company Common Stock..........................................................12
Company Disclosure Letter.....................................................11
Company Employee Plans........................................................23
Company Financials............................................................15
Company Intellectual Property Rights..........................................18
Company Note...................................................................9
Company Option.................................................................9
Company Options................................................................9
Company Preferred Stock.......................................................12
Company Rights................................................................12
Company Rights Agreement......................................................12
Company SEC Reports...........................................................14
Company Stockholder Approval..................................................13
Company Technology............................................................18
Company Trademarks............................................................18
Company Warrants..............................................................10
Computer Software.............................................................18
Confidentiality Agreement.....................................................36
Copyrights....................................................................18
DGCL...........................................................................1
Dissenting Shares..............................................................8
DOJ...........................................................................38
Effect........................................................................49
Effective Time.................................................................4
Environmental Claims..........................................................20
Environmental Laws............................................................20





                                                                           
ERISA.........................................................................23
ERISA Affiliate...............................................................23
Exchange Act...................................................................2
Expiration Date................................................................2
FDA...........................................................................17
FDCA..........................................................................17
Fee Conversion Options.........................................................9
FTC...........................................................................38
Fully Diluted Shares..........................................................54
GAAP..........................................................................15
Governmental Entity...........................................................14
HSR Act.......................................................................14
Indemnified Liability.........................................................40
Indemnified Party.............................................................40
Indemnity Agreement...........................................................27
Independent Directors.........................................................42
Intellectual Property Rights..................................................18
IRS...........................................................................23
Knowledge.....................................................................50
Laws..........................................................................16
License Agreements............................................................18
Liens.........................................................................13
Material Adverse Effect.......................................................49
Material Contract.............................................................14
Materials of Environmental Concern............................................20
Merger.........................................................................4
Merger Agreement..............................................................56
Merger Consideration...........................................................7
Merger Filing..................................................................4
Minimum Tender Condition......................................................54
Nasdaq.........................................................................6
Offer..........................................................................1
Offer Documents................................................................3
Offer Price....................................................................1
Offer to Purchase..............................................................2
Option Plans...................................................................9
Parent.........................................................................1
Parent Board..................................................................44
Patents.......................................................................19
Paying Agent...................................................................7
person........................................................................49
PHS...........................................................................17
Proxy Statement................................................................6
Purchaser......................................................................1
Purchaser Common Stock.........................................................6
Regulation M-A.................................................................3



                                        2


                                                                           
Representatives...............................................................35
Requisite Regulatory Approvals................................................42
Restraints....................................................................44
Schedule 14D-9.................................................................3
Schedule TO....................................................................3
SEC............................................................................2
Section 16 Affiliate..........................................................10
Securities Act................................................................14
Shares.........................................................................1
Significant Company IP........................................................19
Special Meeting................................................................5
Subsequent Determination......................................................37
Subsidiary....................................................................49
Superior Proposal.............................................................36
Surviving Corporation..........................................................4
Takeover Proposal.............................................................36
Tax...........................................................................22
Tax Authority.................................................................22
Tax Returns...................................................................22
Taxes.........................................................................22
Technology....................................................................19
Termination Date..............................................................44
Termination Fee...............................................................46
THP Agreement.................................................................29
Trade Secrets.................................................................19
Trademarks....................................................................19
Transactions..................................................................49
Voting Debt...................................................................12
WARN Act......................................................................25



                                        3


                                TABLE OF CONTENTS



                                                                            Page
                                                                           
ARTICLE I THE MERGER...........................................................2
1.1    THE OFFER...............................................................2
1.2    COMPANY ACTIONS.........................................................3
1.3    THE MERGER..............................................................4
1.4    EFFECTIVE TIME..........................................................4
1.5    CLOSING.................................................................5
1.6    DIRECTORS AND OFFICERS OF THE SURVIVING CORPORATION.....................5
1.7    SUBSEQUENT ACTIONS......................................................5
1.8    STOCKHOLDERS' MEETING...................................................5
1.9    MERGER WITHOUT MEETING OF STOCKHOLDERS..................................6
1.10   ISSUANCE OF COMPANY COMMON STOCK........................................6
ARTICLE II CONVERSION OF SECURITIES............................................6
2.1    CONVERSION OF CAPITAL STOCK.............................................6
2.2    EXCHANGE OF CERTIFICATES................................................7
2.3    DISSENTING SHARES.......................................................8
2.4    THE COMPANY OPTION PLANS................................................9
2.5    OTHER SECURITIES........................................................9
2.6    SECTION 16.............................................................10
2.7    WITHHOLDING............................................................10
2.8    TRANSFER TAXES.........................................................10
ARTICLE III REPRESENTATIONS AND WARRANTIES OF THE COMPANY.....................11
3.1    ORGANIZATION, STANDING AND POWER.......................................11
3.2    CAPITALIZATION.........................................................12
3.3    AUTHORITY; NONCONTRAVENTION............................................13
3.4    SEC FILINGS; COMPANY FINANCIAL STATEMENTS..............................14
3.5    ABSENCE OF CERTAIN CHANGES.............................................15
3.6    NO UNDISCLOSED LIABILITIES.............................................15
3.7    LITIGATION.............................................................16
3.8    GOVERNMENTAL AUTHORIZATION.............................................16
3.9    TITLE TO PROPERTY......................................................18
3.10   TECHNOLOGY AND INTELLECTUAL PROPERTY...................................18
3.11   ENVIRONMENTAL MATTERS..................................................20
3.12   TAXES..................................................................21
3.13   EMPLOYEE BENEFIT PLANS.................................................22
3.14   LABOR MATTERS..........................................................25
3.15   INSURANCE..............................................................25
3.16   COMPLIANCE WITH LAWS...................................................25
3.17   BROKERS' AND FINDERS' FEES.............................................26
3.18   STATE TAKEOVER STATUTES................................................26
3.19   BOARD APPROVAL.........................................................26
3.20   VOTE REQUIRED..........................................................26
3.21   MATERIAL CONTRACTS AND OTHER AGREEMENTS................................26




                                                                           
3.22   INFORMATION IN THE PROXY STATEMENT.....................................27
3.23   INFORMATION IN THE OFFER DOCUMENTS AND THE SCHEDULE 14D-9..............28
3.24   OPINION OF FINANCIAL ADVISOR...........................................28
3.25   RIGHTS PLAN............................................................28
3.26   NO DEFAULT.............................................................28
3.27   PRODUCT LIABILITY......................................................28
3.28   COMMERCIAL RELATIONSHIPS...............................................29
3.29   THERAPEUTIC HUMAN POLYCLONALS, INC.....................................29
ARTICLE IV REPRESENTATIONS AND WARRANTIES OF PARENT AND PURCHASER.............29
4.1    ORGANIZATION, STANDING AND POWER.......................................29
4.2    AUTHORITY; NONCONTRAVENTION............................................30
4.3    INFORMATION IN THE OFFER DOCUMENTS.....................................30
4.4    INFORMATION IN THE PROXY STATEMENT.....................................30
4.5    FINANCING..............................................................31
4.6    OWNERSHIP OF COMPANY STOCK.............................................31
4.7    LITIGATION.............................................................31
4.8    BROKERS' AND FINDERS' FEES.............................................31
ARTICLE V CONDUCT PRIOR TO THE EFFECTIVE TIME.................................31
5.1    CONDUCT OF BUSINESS BY THE COMPANY.....................................31
5.2    NO SOLICITATION........................................................35
ARTICLE VI ADDITIONAL AGREEMENTS..............................................37
6.1    PROXY STATEMENT........................................................37
6.2    MEETING OF STOCKHOLDERS OF THE COMPANY.................................37
6.3    CONFIDENTIALITY; ACCESS TO INFORMATION.................................37
6.4    PUBLIC DISCLOSURE......................................................38
6.5    REGULATORY FILINGS; REASONABLE EFFORTS.................................38
6.6    NOTIFICATION OF CERTAIN MATTERS........................................40
6.7    INDEMNIFICATION........................................................40
6.8    EMPLOYEE BENEFITS......................................................41
6.9    CONSENTS AND APPROVALS.................................................41
6.10   ADDITIONAL AGREEMENTS..................................................42
6.11   DIRECTORS..............................................................42
ARTICLE VII CONDITIONS........................................................43
7.1    CONDITIONS TO OBLIGATIONS OF EACH PARTY TO EFFECT THE MERGER...........43
7.2    ADDITIONAL CONDITION TO THE OBLIGATIONS OF PARENT AND PURCHASER........44
ARTICLE VIII TERMINATION, AMENDMENT AND WAIVER................................44
8.1    TERMINATION............................................................44
8.2    EFFECT OF TERMINATION..................................................46
8.3    FEES AND EXPENSES......................................................47
8.4    EXTENSION; WAIVER......................................................47
ARTICLE IX GENERAL PROVISIONS.................................................47
9.1    NON-SURVIVAL OF REPRESENTATIONS AND WARRANTIES.........................47
9.2    NOTICES................................................................47
9.3    INTERPRETATION; CERTAIN DEFINED TERMS..................................48
9.4    COUNTERPARTS...........................................................50



                                        2


                                                                           
9.5    ENTIRE AGREEMENT; THIRD PARTY BENEFICIARIES............................50
9.6    SEVERABILITY...........................................................50
9.7    OTHER REMEDIES; SPECIFIC PERFORMANCE...................................50
9.8    GOVERNING LAW; VENUE...................................................51
9.9    RULES OF CONSTRUCTION..................................................51
9.10   ASSIGNMENT.............................................................51
9.11   AMENDMENT AND MODIFICATION.............................................51
9.12   NO WAIVER; REMEDIES CUMULATIVE.........................................52
9.13   CONTROL OF COMPANY'S BUSINESS..........................................52
9.14   WAIVER OF JURY TRIAL...................................................52



                                        3


                          AGREEMENT AND PLAN OF MERGER

            THIS AGREEMENT AND PLAN OF MERGER (this "AGREEMENT"), is entered
into as of August 4, 2003 by and among Genzyme Corporation, a Massachusetts
corporation ("PARENT"), Swift Starboard Corporation, a Delaware corporation and
a wholly-owned subsidiary of Parent ("PURCHASER"), and SangStat Medical
Corporation, a Delaware corporation (the "COMPANY").

                                    RECITALS

            WHEREAS, the Board of Directors of each of Parent, Purchaser and the
Company has approved, and deems it advisable and in the best interests of its
respective stockholders to consummate, the acquisition of the Company by Parent
upon the terms and subject to the conditions set forth herein;

            WHEREAS, in furtherance thereof, it is proposed that (i) Purchaser
commence a cash tender offer (as it may be amended from time to time as
permitted by this Agreement, the "OFFER") to acquire all shares of the issued
and outstanding common stock, par value $0.001 per share, of the Company,
including the associated Company Rights (as defined in Section 3.2) (the
"SHARES"), for $22.50 per Share, net to the seller in cash (such price, or any
such higher price per Share as may be paid in the Offer, referred to herein as
the "OFFER PRICE");

            WHEREAS, the Board of Directors of each of Parent, Purchaser and the
Company has approved this Agreement and the Transactions (as defined in Section
9.3(f)), including the Merger (as defined in Section 1.3) following the Offer in
accordance with the Delaware General Corporation Law ("DGCL") and upon the terms
and subject to the conditions set forth herein;

            WHEREAS, the Board of Directors of the Company (the "COMPANY BOARD
OF DIRECTORS") has determined that the consideration to be paid for each Share
in the Offer and the Merger is fair to the holders of such Shares and has
resolved to recommend that the holders of such Shares accept the Offer and adopt
this Agreement and each of the Transactions upon the terms and subject to the
conditions set forth herein; and

            WHEREAS, the Company, Parent and Purchaser desire to make certain
representations, warranties, covenants and agreements in connection with the
Offer, the Merger and the other Transactions.

            NOW, THEREFORE, in consideration of the foregoing and the respective
covenants, agreements, representations and warranties set forth herein, the
parties agree as follows:

                                        1


                                    ARTICLE I

                                   THE MERGER

     1.1    THE OFFER.

            (a) Provided that this Agreement shall not have been terminated in
accordance with Section 8.1 and none of the events set forth in Annex I hereto
shall have occurred, Purchaser shall commence (within the meaning of Rule 14d-2
under the Securities Exchange Act of 1934, as amended (together with the rules
and regulations promulgated thereunder, the "EXCHANGE ACT")), the Offer as
promptly as practicable following the date hereof (but in no case later than ten
(10) business days from the date hereof). The obligations of Purchaser to accept
for payment and to pay for any Shares validly tendered and not withdrawn prior
to the expiration of the Offer (as it may be extended in accordance with
requirements of this Section 1.1(a)) shall be subject only to the conditions set
forth in Annex I hereto. Subject to the prior satisfaction or waiver by Parent
or Purchaser of the conditions of the Offer set forth in Annex I hereto,
Purchaser shall consummate the Offer in accordance with its terms and accept for
payment and pay for all Shares tendered and not withdrawn promptly following the
acceptance of Shares for payment pursuant to the Offer. The Offer shall be made
by means of an offer to purchase (the "OFFER TO PURCHASE") that contains the
terms set forth in this Agreement, and the conditions set forth in Annex I
hereto. Parent expressly reserves the right to waive any of such conditions, to
increase the Offer Price and to make any other changes in the terms of the
Offer; provided, however, that Purchaser shall not, and Parent shall cause
Purchaser not to, decrease the Offer Price, change the form of consideration
payable in the Offer, decrease the number of Shares sought in the Offer, impose
additional conditions to the Offer, extend the offer beyond the date that is
twenty (20) business days after commencement of the Offer or the last extension
(in accordance with this Section 1.1, if any, of the Offer, whichever is later
(the "EXPIRATION DATE") except as set forth below, waive or change the Minimum
Tender Condition (as defined in Annex I) or amend any other condition of the
Offer in any manner adverse to the Company or the holders of the Shares, in each
case without the prior written consent of the Company (such consent to be
authorized by the Company Board of Directors or a duly authorized committee
thereof). Notwithstanding the foregoing, Purchaser may, without the consent of
the Company, (i) extend the Offer beyond the initial expiration date if, at any
scheduled (or extended) expiration of the Offer, any of the conditions to
Purchaser's obligation to accept Shares for payment, shall not be satisfied or
waived, (ii) extend the Offer for any period required by any rule, regulation or
interpretation of the United States Securities and Exchange Commission ("SEC"),
or the staff thereof, applicable to the Offer, or (iii) extend (or re-extend)
the Offer for an aggregate period of not more than twenty (20) business days
(taking into account all such extensions and re extensions), beyond the latest
applicable date that would otherwise be permitted under clause (i) or (ii) of
this sentence, if, as of such date, all of the conditions to Purchaser's
obligations to accept for payment Shares are satisfied or waived, but there
shall not have been validly tendered and not withdrawn pursuant to the Offer
that number of Shares necessary to permit the Merger to be effected without a
meeting of the Company's stockholders in accordance with the DGCL. In addition,
Purchaser may provide a "subsequent offering period" in accordance with Rule
14d-l1 under the Exchange Act.

                                        2


            (b) On the date of commencement of the Offer, Parent and Purchaser
shall file with the SEC, pursuant to Regulation M-A under the Exchange Act
("REGULATION M-A"), a Tender Offer Statement on Schedule TO with respect to the
Offer (together with all amendments, supplements and exhibits thereto, the
"SCHEDULE TO"). The Schedule TO shall include the summary term sheet required
under Regulation M-A and, as exhibits, the Offer to Purchase and a form of
letter of transmittal and summary advertisement (collectively, together with any
amendments and supplements thereto, the "OFFER DOCUMENTS"). The Company hereby
consents to the inclusion in the Offer Documents of the recommendation referred
to in clause (iii) of Section 3.19 and the approval of the Board of Directors
referred to in Section 3.19. Parent and Purchaser agree to take all steps
necessary to cause the Offer Documents to be filed with the SEC and disseminated
to holders of Shares, in each case as and to the extent required by applicable
federal securities laws. Parent and Purchaser, on the one hand, and the Company,
on the other hand, agree to promptly correct any information provided by it for
use in the Offer Documents if and to the extent that it shall have become false
or misleading in any material respect or as otherwise required by law. Parent
and Purchaser further agree to take all steps necessary to cause the Offer
Documents as so corrected to be filed with the SEC and disseminated to holders
of Shares, in each case as and to the extent required by applicable federal
securities laws. The Company and its counsel shall be given a reasonable
opportunity to review the Schedule TO before it is filed with the SEC. In
addition, Parent and Purchaser agree to provide the Company and its counsel with
any comments, whether written or oral, that Parent, Purchaser or their counsel
may receive from time to time from the SEC or its staff with respect to the
Offer Documents promptly upon receipt of such comments, and any written or oral
responses thereto.

            (c) Parent shall provide or cause to be provided to Purchaser upon
expiration of the Offer or any subsequent extension thereof, as applicable, all
funds necessary to accept for payment, and pay for, any shares of Company Common
Stock that are validly tendered and not withdrawn pursuant to the Offer and that
Purchaser is obligated to accept for payment pursuant to the Offer and permitted
to accept for payment under applicable Law.

     1.2    COMPANY ACTIONS.

            (a) On the date the Offer is commenced, the Company shall, in a
manner that complies with Rule 14d-9 under the Exchange Act, file with the SEC a
Tender Offer Solicitation/Recommendation Statement on Schedule 14D-9 (together
with all amendments, supplements and exhibits thereto, the "SCHEDULE 14D-9")
which shall, subject to the provisions of Section 5.2, contain the
recommendation referred to in clause (iii) of Section 3.19 and the approval of
the Board of Directors referred to in Section 3.19. The Company further agrees
to take all steps necessary to cause the Schedule 14D-9 to be filed with the SEC
and disseminated to holders of Shares, in each case as and to the extent
required by applicable federal securities laws. The Company, on the one hand,
and Parent and Purchaser, on the other hand, agree to promptly correct any
information provided by it for use in the Schedule 14D-9 if and to the extent
that it shall have become false or misleading in any material respect or as
otherwise required by law. The Company agrees to take all steps necessary to
cause the Schedule 14D-9 as so corrected to be filed with the SEC and
disseminated to holders of the Shares, in each case as and to the extent
required by applicable federal securities laws. Parent, Purchaser and their
counsel shall be given the opportunity to review and comment on the Schedule
14D-9 and any

                                        3


amendment thereto before filing with the SEC. In addition, the Company agrees to
provide Parent, Purchaser and their counsel in writing with any comments,
whether written or oral, that the Company or its counsel may receive from time
to time from the SEC or its staff with respect to the Schedule 14D-9 promptly
after receipt of such comments, and to consult with Parent, Purchaser and their
counsel prior to responding to any such comments, either in written or oral
form.

            (b) In connection with the Offer, the Company shall promptly furnish
or cause to be furnished to Parent or Purchaser mailing labels, security
position listings and all available listings and computer files containing the
names and addresses of the record holders of the Shares as of a recent date, and
shall promptly furnish Parent or Purchaser with such information and assistance
(including, but not limited to, lists of holders of the Shares, updated
periodically, and their addresses, mailing labels and lists of security
positions) as Parent or Purchaser or its agent(s) may reasonably request. Such
information shall be held confidential by Parent and Purchaser under the terms
of the Confidentiality Agreement.

     1.3    THE MERGER.

            (a) Subject to the terms and conditions of this Agreement, at the
Effective Time (as defined in Section 1.4), the Company and Purchaser shall
consummate a merger (the "MERGER") in accordance with the DGCL pursuant to which
(i) Purchaser shall be merged with and into the Company and the separate
corporate existence of Purchaser shall thereupon cease; (ii) the Company shall
be the successor or surviving corporation in the Merger and shall continue to be
governed by the laws of the State of Delaware; (iii) the separate corporate
existence of the Company with all its rights, privileges, immunities, powers and
franchises shall continue unaffected by the Merger; and (iv) the Company shall
succeed to and assume all the rights and obligations of Purchaser. The
corporation surviving the Merger is sometimes hereinafter referred to as the
"SURVIVING CORPORATION." The Merger shall have the effects set forth in the
DGCL.

            (b) The Certificate of Incorporation of Purchaser, as in effect
immediately prior to the Effective Time, shall be the Certificate of
Incorporation of the Surviving Corporation, except as to the name of the
Surviving Corporation, until thereafter amended as provided by law and such
Certificate of Incorporation.

            (c) The Bylaws of Purchaser, as in effect immediately prior to the
Effective Time, shall be the Bylaws of the Surviving Corporation, except as to
the name of the Surviving Corporation, until thereafter amended as provided by
the DGCL, the Certificate of Incorporation of the Surviving Corporation and such
Bylaws.

     1.4    EFFECTIVE TIME. Parent, Purchaser and the Company shall cause an
appropriate certificate of merger (the "CERTIFICATE OF MERGER") to be executed
and filed on the Closing Date (as defined in Section 1.5) (or on such other date
as Parent and the Company may agree) with the Secretary of State of the State of
Delaware as provided in the DGCL (the "MERGER FILING"). The Merger shall become
effective on the time and date on which the Certificate of Merger has been duly
filed with the Secretary of State of the State of Delaware or such time and date
as is agreed upon by the parties and specified in the Certificate of Merger,
such time hereinafter referred to as the "EFFECTIVE TIME."

                                        4


     1.5    CLOSING. The closing of the Merger (the "CLOSING") will take place
at 9:00 a.m. (Boston time) on a date to be specified by the parties, such date
to be no later than the second business day after satisfaction or waiver of all
of the conditions set forth in Article VII (the "CLOSING DATE"), at the offices
of Ropes & Gray, LLP, One International Place, Boston, Massachusetts 02110,
unless another date or place is agreed to in writing by the parties hereto.

     1.6    DIRECTORS AND OFFICERS OF THE SURVIVING CORPORATION. The directors
of Purchaser immediately prior to the Effective Time shall, from and after the
Effective Time, be the directors of the Surviving Corporation, and the officers
of Purchaser immediately prior to the Effective Time shall, from and after the
Effective Time, be the officers of the Surviving Corporation, in each case until
their respective successors shall have been duly elected, designated or
qualified, or until their earlier death, resignation or removal in accordance
with the Surviving Corporation's Certificate of Incorporation and Bylaws.

     1.7    SUBSEQUENT ACTIONS. If at any time after the Effective Time the
Surviving Corporation shall determine, in its sole discretion, or shall be
advised, that any deeds, bills of sale, assignments, assurances or any other
actions or things are necessary or desirable to vest, perfect or confirm of
record or otherwise in the Surviving Corporation its right, title or interest
in, to or under any of the rights, properties or assets of either of the Company
or Purchaser acquired or to be acquired by the Surviving Corporation as a result
of, or in connection with, the Merger or otherwise to carry out this Agreement,
then the officers and directors of the Surviving Corporation shall be authorized
to execute and deliver, in the name and on behalf of either the Company or
Purchaser, all such deeds, bills of sale, instruments of conveyance, assignments
and assurances and to take and do, in the name and on behalf of each such
corporation or otherwise, all such other actions and things as may be necessary
or desirable to vest, perfect or confirm any and all right, title or interest
in, to and under such rights, properties or assets in the Surviving Corporation
or otherwise to carry out this Agreement.

     1.8    STOCKHOLDERS' MEETING.

            (a) If required by applicable law in order to consummate the Merger,
the Company, acting through the Company Board of Directors, shall, in accordance
with applicable law and the Company's Certificate of Incorporation and Bylaws:

                  (i)   duly call, give notice of, convene and hold a special
meeting of its stockholders to consider the approval and adoption of this
Agreement and the approval of the Merger (the "SPECIAL MEETING") as soon as
reasonably practicable following the acceptance for payment and purchase of
Shares by Purchaser pursuant to the Offer for the purpose of considering and
taking action upon this Agreement;

                  (ii)  prepare and file with the SEC under the Exchange Act a
preliminary proxy or information statement relating to the Merger and this
Agreement and use its reasonable efforts to obtain and furnish the information
required to be included by the SEC in the Proxy Statement (as hereinafter
defined) and, after Parent and its counsel shall have had a reasonable
opportunity to review and comment on the Proxy Statement, respond promptly to
any comments made by the SEC with respect to the preliminary proxy or
information statement and cause a definitive proxy or information

                                        5


statement (the "PROXY STATEMENT") to be mailed to its stockholders as promptly
as practicable;

                  (iii) include in the Proxy Statement the recommendation of the
Company Board of Directors that stockholders of the Company vote in favor of the
approval of the Merger and the adoption of this Agreement; and

                  (iv)  use its reasonable efforts to solicit from holders of
Shares proxies in favor of the Merger and take all other action reasonably
necessary or advisable to secure the approval of stockholders required by the
DGCL and any other applicable law and the Company's Certificate of Incorporation
and Bylaws (if applicable) to effect the Merger;

provided that the obligations set forth in clauses (iii) and (iv) of this
Section 1.8(a) shall be subject to Section 5.2.

            (b) Parent agrees to vote, or cause to be voted, all of the Shares
then beneficially owned by it, Purchaser or any of its other subsidiaries in
favor of the approval of the Merger and the adoption of this Agreement.

     1.9    MERGER WITHOUT MEETING OF STOCKHOLDERS. Notwithstanding Section 1.8,
in the event that Parent, Purchaser or any other subsidiary of Parent shall
acquire at least ninety percent (90%) of the outstanding shares of each class of
capital stock of the Company entitled to vote on the Merger, pursuant to the
Offer or otherwise, the parties hereto agree, at the request of Parent and
subject to Article VII, to take all necessary and appropriate action to cause
the Merger to become effective as soon as practicable after such acquisition,
without a meeting of stockholders of the Company, in accordance with and subject
to the DGCL.

     1.10   ISSUANCE OF COMPANY COMMON STOCK. Subject to compliance with
applicable law and the rules and regulations of the Nasdaq Stock Market, Inc.
("NASDAQ"), in the event that the Parent, Purchaser or any other subsidiary of
Parent shall acquire at least seventy-five percent (75%), but less than ninety
percent (90%) of the outstanding shares of each class of capital stock of the
Company entitled to vote on the Merger pursuant to the Offer, the Company shall,
at the request of Parent, issue and sell to Purchaser up to the number of shares
of Company Common Stock that represent nineteen and nine-tenths percent (19.9%)
of the outstanding shares of Common Stock of the Company entitled to vote on the
Merger at the greater of a purchase price of $22.50 per share and any higher
price paid for any Share in the Offer.

                                   ARTICLE II

                            CONVERSION OF SECURITIES

     2.1    CONVERSION OF CAPITAL STOCK. As of the Effective Time, by virtue of
the Merger and without any action on the part of the holders of any shares of
Company Common Stock or any shares of common stock, par value $0.001 per share,
of Purchaser ("PURCHASER COMMON STOCK"):

                                        6


            (a) Purchaser Common Stock. Each issued and outstanding share of
Purchaser Common Stock shall be converted into and become one fully paid and
nonassessable share of common stock of the Surviving Corporation.

            (b) Cancellation of Treasury Stock and Parent-Owned Stock. All
Shares that are owned by the Company as treasury stock and any Shares owned by
Parent or Purchaser shall automatically be cancelled and retired and shall cease
to exist, and no consideration shall be delivered in exchange therefor.

            (c) Conversion of Shares. Each issued and outstanding Share (other
than Shares to be cancelled in accordance with Section 2.1(b) and other than
Dissenting Shares (as defined in Section 2.3(a))) shall be converted into the
right to receive the Offer Price, payable to the holder thereof in cash, without
interest (the "MERGER CONSIDERATION"). From and after the Effective Time, all
such Shares shall no longer be outstanding and shall automatically be cancelled
and retired and shall cease to exist, and each holder of a certificate
representing any such Shares shall cease to have any rights with respect
thereto, except the right to receive the Merger Consideration therefor upon the
surrender of such certificate in accordance with Section 2.2, without interest
thereon.

     2.2    EXCHANGE OF CERTIFICATES.

            (a) Paying Agent. Parent shall designate a bank or trust company to
act as agent for the holders of Shares in connection with the Merger (the
"PAYING AGENT") and to receive the funds to which holders of Shares shall become
entitled pursuant to Section 2.1(c). Prior to the Effective Time, Parent shall
deposit, or cause to be deposited (by Purchaser or otherwise), with the Paying
Agent the aggregate Merger Consideration. For purposes of determining the amount
of Merger Consideration to be so deposited, Parent and Purchaser shall assume
that no stockholder of the Company will perfect any right to appraisal of his,
her or its Shares. Such funds shall be invested by the Paying Agent as directed
by Parent or the Surviving Corporation, in its sole discretion (provided that
Parent shall be responsible for replacing any losses of principal to such fund
resulting from such investments), pending payment thereof by the Paying Agent to
the holders of the Shares. Earnings from such investments shall be the sole and
exclusive property of Parent and the Surviving Corporation, and no part of such
earnings shall accrue to the benefit of holders of Shares.

            (b) Exchange Procedures. Promptly after the Effective Time, the
Paying Agent shall mail to each holder of record of a certificate or
certificates, which immediately prior to the Effective Time represented
outstanding Shares (the "CERTIFICATES"), whose shares were converted pursuant to
Section 2.1(c) into the right to receive the Merger Consideration (i) a letter
of transmittal (which shall specify that delivery shall be effected, and risk of
loss and title to the Certificates shall pass, only upon delivery of the
Certificates to the Paying Agent and shall be in such form and have such other
provisions as Parent may reasonably specify); and (ii) instructions for
effecting the surrender of the Certificates in exchange for payment of the
Merger Consideration. Upon surrender of a Certificate for cancellation to the
Paying Agent or to such other agent or agents as may be appointed by Parent,
together with such letter of transmittal, duly executed and properly completed,
the holder of such Certificate shall be entitled to receive in exchange therefor
the Merger Consideration for each Share formerly represented by such

                                        7


Certificate and the Certificate so surrendered shall forthwith be cancelled.
Until surrendered as contemplated by this Section 2.2, each Certificate shall be
deemed at any time after the Effective Time to represent only the right to
receive the Merger Consideration in cash as contemplated by this Section 2.2,
without interest thereon, and shall not evidence any interest in, or any right
to exercise the rights of a stockholder or other equity holder of, the Company
or the Surviving Corporation. Notwithstanding the foregoing, any surrendered
Certificate that represents Dissenting Shares shall be returned to the person
surrendering such certificate.

            (c) Transfer Books; No Further Ownership Rights in Shares. At the
Effective Time, the stock transfer books of the Company shall be closed and
thereafter there shall be no further registration of transfers of Shares on the
records of the Company. From and after the Effective Time, the holders of
Certificates evidencing ownership of Shares outstanding immediately prior to the
Effective Time shall cease to have any rights with respect to such Shares,
except as otherwise provided for herein or by applicable law. If, after the
Effective Time, Certificates are presented to the Surviving Corporation for any
reason, they shall be cancelled and exchanged as provided in this Article II.

            (d) Termination of Fund; No Liability. At any time following six (6)
months after the Effective Time, the Surviving Corporation shall be entitled to
require the Paying Agent to deliver to it any funds (including any interest
received with respect thereto) made available to the Paying Agent and not
disbursed (or for which disbursement is pending subject only to the Paying
Agent's routine administrative procedures) to holders of Certificates, and
thereafter such holders shall be entitled to look only to the Surviving
Corporation (subject to abandoned property, escheat or other similar laws) only
as general creditors thereof with respect to the Merger Consideration payable
upon due surrender of their Certificates, without any interest thereon.
Notwithstanding the foregoing, none of Parent, the Surviving Corporation nor the
Paying Agent shall be liable to any holder of a Certificate for Merger
Consideration delivered to a public official pursuant to any applicable
abandoned property, escheat or similar law. If Certificates are not surrendered
prior to two (2) years after the Effective Time, unclaimed Merger Consideration
payable with respect to such Shares shall, to the extent permitted by applicable
law, become the property of the Surviving Corporation, free and clear of all
claims or interest of any person previously entitled thereto.

            (e) Lost Certificates. If any Certificate shall have been lost,
stolen or destroyed, upon the making of an affidavit of that fact by the person
claiming such Certificate to be lost, stolen or destroyed and, if required by
Parent, the posting by such person of a bond in such amount as Parent may
reasonably direct as indemnity against any claim that may be made against it or
the Surviving Corporation with respect to such Certificate, the Paying Agent
shall issue in exchange for such lost, stolen or destroyed Certificate the
applicable Merger Consideration with respect thereto.

     2.3    DISSENTING SHARES.

            (a) Notwithstanding anything in this Agreement to the contrary,
Shares outstanding immediately prior to the Effective Time and held by a holder
who has not voted in favor of the Merger or consented thereto in writing and who
has complied with Section 262 of the DGCL (the "DISSENTING SHARES") shall not be
converted into a right to receive the Merger

                                        8


Consideration, unless such holder fails to perfect or withdraws or otherwise
loses his, her or its right to appraisal. From and after the Effective Time, a
stockholder who has properly exercised such appraisal rights shall not have any
rights of a stockholder of the Company or the Surviving Corporation with respect
to such Shares, except those provided under Section 262 of the DGCL. A holder of
Dissenting Shares shall be entitled to receive payment of the appraised value of
such Shares held by him, her or it in accordance with Section 262 of the DGCL,
unless, after the Effective Time, such holder fails to perfect or withdraws or
loses his, her or its right to appraisal, in which case such Shares shall be
converted into and represent only the right to receive the Merger Consideration,
without interest thereon, upon surrender of the Certificate or Certificates
representing such Shares, pursuant to Section 2.2.

            (b) The Company shall give Parent (i) prompt notice of any written
demands for appraisal of any Shares, attempted withdrawals of such demands and
any other instruments served pursuant to the DGCL and received by the Company
relating to rights of appraisal; and (ii) the opportunity to participate in the
conduct of all negotiations and proceedings with respect to demands for
appraisal under the DGCL. Except with the prior written consent of Parent, the
Company shall not voluntarily make any payment with respect to any demands for
appraisal or settle or offer to settle any such demands for appraisal.

     2.4    THE COMPANY OPTION PLANS. Effective as of the Effective Time, each
outstanding stock option, stock equivalent right or right to acquire Shares (a
"COMPANY OPTION" or "COMPANY OPTIONS") granted under the Company's 1996
Non-Employee Director Stock Option Plan (including, but not limited to, options
granted in lieu of a director's basic retainer payment ("FEE CONVERSION
OPTIONS"), and the 2002 Stock Option Plan (collectively, the "OPTION PLANS")),
whether or not then exercisable or vested, shall be (i) deemed to be one hundred
percent (100%) vested and exercisable immediately prior to the Effective Time;
and (ii) immediately prior to the Effective Time, cancelled and, in
consideration of such cancellation, Parent shall, or shall cause the Surviving
Corporation to, promptly following the Effective Time, pay to such holders of
Company Options, an amount in respect thereof equal to the product of (x) the
excess, if any, of the Offer Price over the exercise price of each such Company
Option and (y) the number of unexercised Shares subject thereto (such payment,
if any, to be net of applicable Taxes withheld pursuant to Section 2.6).
Effective as of the Effective Time, all repurchase rights in favor of the
Company with respect to shares issued upon exercise of Company Options
(including, but not limited to shares issued upon exercise of Fee Conversion
Options) shall terminate automatically, and the unvested shares of Common Stock
subject to those terminated rights shall immediately vest in full. As of the
Effective Time, the Option Plans shall terminate and all rights under any
provision of any other plan, program or arrangement providing for the issuance
or grant of any other interest in respect of the capital stock of the Company or
any Company Subsidiary shall be cancelled. The Company shall use all reasonable
efforts to effectuate the foregoing, including, but not limited to, sending out
the requisite notices and obtaining all consents necessary to cash out and
cancel all Company Options necessary to ensure that, after the Effective Time,
no person shall have any right under the Option Plans, except as set forth
herein.

     2.5    OTHER SECURITIES. (a) At the Effective Time, if the $10 million
Convertible Promissory Note due March 29, 2004 by the Company in favor of
Warburg Dillon Read LLC (the "COMPANY NOTE") shall not have been converted by
the holder thereof, the Company Note

                                        9


shall be assumed by Parent. The Company Note assumed by Parent shall have and be
subject to, and convertible upon, the terms and conditions set forth in the
Company Note, except that the Company Note shall be convertible only into such
Merger Consideration receivable by a holder of that number of shares of Company
Common Stock into which the holder would have received had such holder converted
the Company Note in full immediately prior to the Effective Time, in accordance
with Section 1(h) of the Company Note. Promptly after the commencement of the
Offer, Parent shall execute and deliver to the holder of the Company Note a
supplemental agreement regarding the conversion of the Company Note following
the Effective Time in accordance with Sections 1(h) and 4(a)(1) of the Company
Note and the Company shall deliver to the holder of the Company Note the
officer's certificate and legal opinion contemplated by Section 4(a)(3) of the
Company Note.

     (b) COMPANY WARRANT. Promptly after the commencement of the Offer, the
Company shall deliver to each holder of a warrant to purchase Company Common
Stock (the "COMPANY WARRANTS") a notice regarding the Transactions, as
contemplated by the second paragraph of the introduction to the Company
Warrants.

     2.6    SECTION 16. Parent, Surviving Corporation and the Company shall take
such steps with respect to each Section 16 Affiliate (as defined below) as
contemplated by the terms and conditions set forth in that certain No-Action
Letter, dated January 12, 1999, issued by the SEC to Skadden, Arps, Slate,
Meagher & Flom LLP. For purposes of this Agreement, "SECTION 16 AFFILIATE" shall
mean each individual who (x) immediately prior to the Effective Time is a
director or officer of the Company or (y) at the Effective Time will become a
director or officer of Parent.

     2.7    WITHHOLDING. Each of the Paying Agent, Parent, and Surviving
Corporation shall be entitled to deduct and withhold, or cause the Paying Agent
to deduct and withhold, from any amounts payable or otherwise deliverable
pursuant to this Agreement to any holder or former holder of Shares or the
Company Options such amounts as are required to be deducted or withheld
therefrom under the Internal Revenue Code of 1986, as amended (the "CODE") or
any provision of Tax law or under any other applicable legal requirement. To the
extent such amounts are so deducted or withheld, such amounts shall be treated
for all purposes under this Agreement as having been paid to the person to whom
such amounts would otherwise have been paid.

     2.8    TRANSFER TAXES. If payment of the Offer Price payable to a holder of
Shares pursuant to the Offer or the Merger is to be made to a person other than
the person in whose name the surrendered Certificate is registered, it shall be
a condition of payment that the Certificate so surrendered shall be properly
endorsed or shall be otherwise in proper form for transfer and that the person
requesting such payment shall have paid all transfer and other Taxes required by
reason of the issuance to a person other than the registered holder of the
Certificate surrendered or shall have established to the satisfaction of Parent
that such Tax either has been paid or is not applicable.

                                       10


                                   ARTICLE III

                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

            Except as disclosed in that section of the letter of even date
herewith delivered by the Company to Parent prior to the execution and delivery
of this Agreement (the "COMPANY DISCLOSURE LETTER") corresponding to the section
of this Agreement to which any of the following representations or warranties
pertain, the Company represents and warrants to Parent as set forth below. For
purposes of the representations and warranties of the Company contained herein,
disclosure in any section of the Company Disclosure Letter of any facts or
circumstances shall be deemed to be adequate response and disclosure of such
facts or circumstances with respect to all representations or warranties by the
Company calling for disclosure of such information, whether or not such
disclosure is specifically associated with or purports to respond to one or more
or all of such representations or warranties if it is reasonably apparent on the
face of the Company Disclosure Letter that such disclosure is applicable. The
inclusion of any information in any section of the Company Disclosure Letter or
other document delivered by the Company pursuant to this Agreement shall not be
deemed to be an admission or evidence of the materiality of such item, nor shall
it establish a standard of materiality for any purpose whatsoever.

     3.1    ORGANIZATION, STANDING AND POWER. The Company and each of its
Subsidiaries is a corporation or other legal entity duly organized, validly
existing and in good standing under the laws of its jurisdiction of
organization. Each of the Company and its Subsidiaries has the corporate power
to own, lease and operate its properties and to carry on its business as now
being conducted and is duly qualified to do business and is in good standing in
each jurisdiction in which the nature of its business as conducted makes such
qualification or licensing necessary, except where the failure to be so
qualified and in good standing would not be reasonably likely to have a Material
Adverse Effect on the Company and its Subsidiaries taken as a whole. The Company
has made available a true and correct copy of the Certificate of Incorporation
and Bylaws, or other equivalent charter documents, as applicable, of the Company
and each of its Subsidiaries, each as amended to date, to Parent. Neither the
Company nor any of its Subsidiaries is in violation of any of the provisions of
its Certificate of Incorporation or Bylaws or equivalent charter documents, as
applicable. Other than its interest in its wholly owned Subsidiaries, the
Company does not directly or indirectly own any equity or similar interest in,
or any interest convertible or exchangeable or exercisable for, any equity or
similar interest in, any corporation, partnership, joint venture or other
business association or entity. Section 3.1 of the Company Disclosure Letter
sets forth a true and complete list of the names, jurisdictions of organization
of each of the Company's Subsidiaries. Section 3.1 of the Company Disclosure
Letter also sets forth for each such Subsidiary the individuals who comprise the
board of directors or comparable body for each such entity, except as otherwise
noted on such Section of the Company Disclosure Letter. The Company agrees to
take, or cause to be taken, the actions necessary so that the individuals who
comprise the board of directors or comparable body for each such entity will
resign and be replaced by individuals specified by Parent effective as of the
Effective Time.

                                       11


     3.2    CAPITALIZATION.

            (a) The authorized capital stock of the Company consists of (i)
40,000,000 shares of common stock, par value $.001 per share ("COMPANY COMMON
STOCK"), of which 26,469,087 shares were issued and outstanding as of June 30,
2003, and (ii) 5,000,000 shares of preferred stock, par value $.001 per share
("COMPANY PREFERRED STOCK" and, together with Company Common Stock, "COMPANY
CAPITAL STOCK"), of which no shares are issued and outstanding as of the date
hereof. As of June 30, 2003, (i) no shares of Company Common Stock and no shares
of Company Preferred Stock are issued and held in the treasury of the Company,
(ii) 4,351,165 shares of Company Common Stock were reserved for issuance
pursuant to outstanding Company Options pursuant to the Company Option Plans,
(iii) there were warrants outstanding to purchase 50,000 shares of Company
Common Stock pursuant to the Company Warrants, (iv) there was Voting Debt (as
defined below) outstanding to purchase 500,773 shares of Company Common Stock
pursuant to the Company Note and (v) 500,000 shares of Company Preferred Stock
were designated as Series A Junior Participating Preferred Stock, all of which
were reserved for issuance upon exercise of preferred stock purchase rights (the
"COMPANY RIGHTS") issuable pursuant to the Rights Agreement, dated as of August
14, 1995, by and between the Company and Equiserve Trust Company, N.A., as
rights agent (the "COMPANY RIGHTS AGREEMENT"). All of the outstanding shares of
Company Capital Stock are, and all shares of Company Capital Stock which may be
issued pursuant to the exercise or conversion of outstanding Company Options,
Company Warrants or the Company Note will be, when issued in accordance with the
respective terms thereof or instruments relating thereto, duly authorized,
validly issued, fully paid and non-assessable. The rights, preferences and
privileges of the Company Preferred Stock are as set forth in the Certificate of
Incorporation of the Company.

            (b) Except as set forth in Section 3.2(a) above (i) there are no
shares of capital stock of the Company authorized, issued or outstanding; (ii)
there are no existing options, warrants, calls, purchase rights, conversion
rights, exchange rights, stock appreciation rights preemptive rights,
indebtedness having general voting rights or debt convertible into securities
having such rights ("VOTING DEBT") or subscriptions or other rights, agreements,
arrangements or commitments of any character, relating to the issued or unissued
capital stock or treasury shares of the capital stock of the Company or its
Subsidiaries or obligating the Company or any of its Subsidiaries to issue,
transfer or sell or cause to be issued, transferred or sold any shares of
capital stock or Voting Debt of, or other equity interest in, the Company or any
of its Subsidiaries or securities convertible into or exchangeable for such
shares or equity interests, or obligating the Company or any of its Subsidiaries
to grant, extend or enter into any such option, warrant, call, subscription or
other right, agreement, arrangement or commitment; and (iii) there are no
outstanding contractual obligations of the Company or any of its Subsidiaries to
repurchase, redeem or otherwise acquire any Company Capital Stock, or other
capital stock of the Company or any of its Subsidiaries or to provide funds to
make any investment (in the form of a loan, capital contribution or otherwise)
in any other entity. There are no voting trusts or other agreements or
understandings to which the Company or any of its Subsidiaries is a party with
respect to the voting of the capital stock of the Company or any of its
Subsidiaries.

            (c) Each outstanding share of capital stock of each Subsidiary of
the Company is duly authorized, validly issued, fully paid and nonassessable and
each such share owned by the Company or any Subsidiary of the Company is owned
free and clear of any mortgage, pledge,

                                       12


assessment, security interest, lease, sublease, lien, adverse claim, levy,
charge, option, right of others or restriction (whether on voting, sale,
transfer, disposition or otherwise) or other encumbrance of any kind, whether
imposed by agreement, understanding, law or equity, or any conditional sale
contract, title retention contract or other contract to give or to refrain from
giving any of the foregoing (collectively, "LIENS").

            (d) Section 3.2(d) of the Company Disclosure Letter sets forth a
listing of (i) all outstanding Company Options as of the date hereof, which
schedule shows the underlying shares that have vested, the date such options
were issued, and whether the option is an incentive stock option, and (ii) each
outstanding Company Option that will accelerate, in whole or in part, pursuant
to its terms as a result of the transactions contemplated hereby. Any such
acceleration of Company Options is required under the terms of the Option Plans.
No agreement or understanding requires a consent or approval from any holder of
any Company Option or Company Warrant or the Company Note to effectuate the
terms of this Agreement. The Company has previously provided true and complete
copies of all the Company Warrants and the Company Note to Parent.

            (e) Except for (i) shares indicated as issued and outstanding in
Section 3.2(a) and (ii) shares issued pursuant to Section 1.10, there will not
be, immediately prior to the Effective Time, any shares of Company Common Stock
issued and outstanding.

     3.3    AUTHORITY; NONCONTRAVENTION.

            (a) The Company has the requisite power and authority to enter into
this Agreement (subject to obtaining approval and adoption of this Agreement by
the affirmative vote of the holders of a majority of the outstanding shares of
Company Common Stock (the "COMPANY STOCKHOLDER APPROVAL")) to consummate the
Transactions. The execution, delivery and performance by the Company of this
Agreement and the consummation of the Transactions have been duly authorized by
all necessary corporate action on the part of the Company, subject only to the
Company Stockholder Approval. This Agreement has been duly executed and
delivered by the Company and, assuming this Agreement constitutes the valid and
binding obligation of the other parties hereto and thereto, constitutes the
valid and binding obligation of the Company enforceable against the Company in
accordance with its terms, except to the extent that enforceability may be
limited by the effect, if any, of (i) any applicable bankruptcy, reorganization,
insolvency, moratorium or other laws affecting the enforcement of creditors'
rights generally, and (ii) general principles of equity, regardless of whether
such enforceability is considered in a proceeding at law or in equity.

            (b) The execution, delivery and performance of this Agreement by the
Company does not, and the consummation of the Transactions or compliance by the
Company with any of the provisions hereof or thereof will not, conflict with, or
result in any violation of, or default under (with or without notice or lapse of
time, or both), or give rise to a right of termination, cancellation, right of
payment or acceleration of any obligation, modification of or loss of any
benefit under (i) any provision of the Certificate of Incorporation or Bylaws,
or other equivalent charter documents, as applicable, of the Company or any of
its Subsidiaries, or (ii) any material note, bond, mortgage, indenture,
guarantee, other evidence of indebtedness, lease, License Agreement, contract,
agreement or other instrument or obligation to which the Company or any

                                       13


of its Subsidiaries is a party or by which any of them or any of their
properties or assets may be bound (a "MATERIAL CONTRACT") or any material
permit, concession, franchise, license, judgment, order, decree, statute, law,
ordinance, rule or regulation applicable to the Company or any of its
Subsidiaries or any of their respective properties or assets, except in the case
of clause (ii) where such violation, breach or default individually or in the
aggregate would not be reasonably likely to have a Material Adverse Effect on
the Company and its Subsidiaries taken as a whole or materially impair the
ability of the Company to consummate the Transactions. Except for (i) compliance
with any applicable requirements of the Exchange Act, or the Securities Act of
1933, as amended (the "SECURITIES ACT"), (ii) the Merger Filings, (iii) the
Nasdaq and the State of Delaware, (iv) the Company Stockholder Approval, if
required, (v) such filings and approvals as may be required by any applicable
state securities, blue sky or takeover laws, (vi) filings, clearances, permits,
authorizations, consents and approvals as may be required under the
Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR
ACT"), and any comparable provisions under any applicable pre-merger
notification laws or regulations of foreign jurisdictions, and (vii) such other
consents, authorizations, filings, approvals and registrations which are
obtained prior to the Closing or if not obtained or made would materially reduce
the value of the Company or materially impair the ability of the Company to
consummate the Transactions, no notice to, filing with, and no permit,
authorization, consent or approval of, any arbitrator, court, nation,
government, any state or other political subdivision thereof and any entity
exercising executive, legislative, judicial regulatory or administrative
functions of, or pertaining to, government (a "GOVERNMENTAL ENTITY"), or any
private third party is necessary for the consummation by the Company of the
Transactions. The execution, delivery and performance of this Agreement by the
Company does not and the consummation of the Transactions or compliance by the
Company with any of the provisions hereof or thereof will not result in the
creation of any Lien on the assets or properties of the Company or any of its
Subsidiaries. Neither the Company nor any of its Subsidiaries is or will be
required to give any notice to or obtain any consent or waiver from any
individual or entity in connection with the execution and delivery of this
Agreement or the consummation of the transactions contemplated hereby or
thereby, except where failure to give such notice or obtain such consent would
not be reasonably likely to have a Material Adverse Effect on the Company and
its Subsidiaries taken as a whole.

     3.4    SEC FILINGS; COMPANY FINANCIAL STATEMENTS.

            (a) The Company has filed all forms, reports and documents required
to be filed by the Company with the SEC since December 31, 2001 and has made
available to Parent such forms, reports and documents in the form filed with the
SEC. All such required forms, reports and documents are referred to herein as
the "COMPANY SEC REPORTS." As of their respective dates or, if amended, as of
the date of the last such amendment prior to the date of this Agreement, the
Company SEC Reports (i) complied in all material respects with the requirements
of the Securities Act or the Exchange Act, as the case may be, the
Sarbanes-Oxley Act of 2002 and the rules and regulations of the SEC thereunder
applicable to such Company SEC Reports and (ii) did not at the time they were
filed (or if amended or superseded by a filing prior to the date of this
Agreement, then on the date of such filing) contain any untrue statement of a
material fact or omit to state a material fact or disclose any matter or
proceeding required to be stated therein or necessary in order to make the
statements therein, in the light of the circumstances under which they were
made, not misleading. Between the date of this Agreement

                                       14


and the Closing Date will timely file, with the SEC all documents required to be
filed by it under the Exchange Act.

            (b) Each of the consolidated financial statements (including, in
each case, any related notes thereto) contained in the Company SEC Reports (the
"COMPANY FINANCIALS") (i) complied in all material respects with the published
rules and regulations of the SEC with respect thereto, (ii) was prepared in
accordance with United States generally accepted accounting principles ("GAAP")
applied on a consistent basis throughout the periods involved (except as may be
indicated in the notes thereto or, in the case of unaudited interim financial
statements, as may be permitted by the SEC on Form 10-Q under the Exchange Act),
(iii) fairly presented in all material respects the consolidated financial
position of the Company and its Subsidiaries as at the respective dates thereof
and the consolidated results of the Company's operations and cash flows for the
periods indicated, except that the unaudited interim financial statements may
not contain footnotes and were or are subject to normal and recurring year-end
adjustments and (iv) was prepared from and in accordance with the Company's
books and records. The balance sheet of the Company contained in the Company SEC
Reports as of March 31, 2003 (the "COMPANY BALANCE SHEET DATE") as filed with
the SEC before the date hereof is hereinafter referred to as the "COMPANY
BALANCE SHEET."

            (c) Within 10 business days of the date hereof, the Company will
provide to the Purchaser a complete list of all effective registration
statements filed on Form S-3 or Form S-8 or otherwise relying on Rule 415 under
the Securities Act.

     3.5    ABSENCE OF CERTAIN CHANGES. Except as and to the extent disclosed in
the Company SEC Reports filed prior to the date of this Agreement, since the
Company Balance Sheet Date and through the date of this Agreement: (i) the
Company and its Subsidiaries have conducted their respective businesses and
operations in all material respects in the ordinary and usual course, (ii) there
has not been any declaration, setting aside or payment of any dividend on, or
other distribution (whether in case, stock or property) in respect of, any of
the Company's capital stock, or any purchase, redemption or other acquisition by
the Company of any of its capital stock or any other securities of the Company
on any options, warrants, calls or rights to acquire any such shares or other
securities except for repurchases from employees following their termination
pursuant to the terms of their pre-existing stock option on purchase agreements,
(iii) the Company has not acquired or agreed to acquire any assets other than in
the ordinary course of business consistent with past practice, (iv) there has
not been any split, combination or reclassification of any of the Company's
capital stock, and (v) there has not occurred any events, changes or effects
(including the incurrence of any liabilities of any nature, whether or not
accrued, contingent or otherwise) having, individually or in the aggregate, or,
which, individually or in the aggregate, would be reasonably likely to have, a
Material Adverse Effect on the Company and its Subsidiaries taken as a whole or
(vi) any change by the Company in accounting principles or methods, except
insofar as may be required by a change in GAAP. There has not been any action
taken by the Company or any of its Subsidiaries since the Balance Sheet Date
through the date of this Agreement that, if taken during the period from the
date of this Agreement through the Effective Time, would constitute a breach of
Section 5.1.

     3.6    NO UNDISCLOSED LIABILITIES. As of March 31, 2003, the Company and
its Subsidiaries had no material liabilities of any nature, whether accrued,
absolute, contingent or

                                       15


otherwise (including without limitation, liabilities as guarantor or otherwise
with respect to obligations of others or liabilities for taxes due or then
accrued or to become due), required to be reflected or disclosed on the Company
Balance Sheet that were not adequately reflected or reserved against on the
Company Balance Sheet. The Company has no material liabilities of any nature,
whether accrued, absolute, contingent or otherwise, that would be required to be
reflected or disclosed in accordance with GAAP on a balance sheet, other than
liabilities (i) adequately reflected or reserved against on the Company Balance
Sheet, (ii) included in Section 3.6 of the Company Disclosure Letter, (iii)
incurred since March 31, 2003 in the ordinary course of business consistent with
past practice or (iv) litigation, as contemplated in Section 3.7 below, for any
claims filed since March 31, 2003.

     3.7    LITIGATION. Except as set forth in the Company SEC Reports filed
prior to the date hereof, (a) there are no private or governmental actions,
suits, proceedings, claims, arbitrations or investigations pending before any
agency, court or tribunal, foreign or domestic, or to the Knowledge of the
Company, threatened against the Company or its Subsidiaries or any of their
properties, directors or officers, including without limitation medical
malpractice or professional liability suits, claims, actions, proceedings,
arbitrations or investigations related to activities of the Company or any of
its Subsidiaries in connection with any web sites sponsored or operated, or
formerly sponsored or operated, by the Company or any of its Subsidiaries and
(b) there is no judgment, decree or order against the Company or any of its
Subsidiaries, that, in the case of (a) or (b) individually or in the aggregate,
would be reasonably likely to have a Material Adverse Effect on the Company and
its Subsidiaries taken as a whole.

     3.8    GOVERNMENTAL AUTHORIZATION. The Company and its Subsidiaries have
each Federal, state, county, local or foreign governmental consent, license,
permit, grant, or other authorization of a Governmental Entity (i) pursuant to
which the Company or any of its Subsidiaries currently operates or holds any
interest in any of its properties or (ii) that is required for the operation of
the business of the Company or any of its Subsidiaries or the holding of any
such interest ((i) and (ii) are herein collectively called "COMPANY
AUTHORIZATIONS"), and all of such Company Authorizations are in full force and
effect, except where the failure to obtain or have any such Company
Authorizations would not reasonably be likely to have a Material Adverse Effect
on the Company; and no proceeding is pending or, to the Knowledge of the
Company, threatened to revoke or limit any Company Authorization, except where
such proceedings would not reasonably be likely to have a Material Adverse
Effect on the Company and its Subsidiaries taken as a whole.

            (b) The Company and its Subsidiaries have complied in a timely
manner and in all material respects, with all laws, statutes, regulations,
rules, ordinances, and judgments, decrees, orders, writs and injunctions, of any
court or Governmental Entity (collectively, "LAWS") relating to any of the
property owned, leased or used by them, or applicable to their business,
including, but not limited to, (i) the Foreign Corrupt Practices Act of 1977 and
any other Laws regarding use of funds for political activity or commercial
bribery and (ii) laws relating to equal employment opportunity, discrimination,
occupational safety and health, environmental, interstate commerce,
anti-kickback, healthcare and antitrust, except where such failure to comply
would not reasonably be likely to have a Material Adverse Effect on the Company
and its Subsidiaries taken as a whole.

                                       16


            (c) The Company and its Subsidiaries are not in violation of any
Federal, state, local or foreign law, ordinance or regulation, including without
limitation the Sarbanes-Oxley Act of 2002 and any rules and regulations
promulgated thereunder, or any order, judgment, injunction, decree or other
requirement of any court, arbitrator or governmental or regulatory body,
relating to the operation of clinical testing laboratories, labor and employment
practices, health and safety, zoning, pollution or protection of the environment
except for violations of or liabilities under any of the foregoing which would
not reasonably be likely to have a Material Adverse Effect on the Company or its
Subsidiaries taken as a whole.

            (d) To the Knowledge of the Company, each product and product
candidate subject to the United States Food and Drug Administration (the "FDA")
jurisdiction under the Federal Food, Drug and Cosmetic Act ("FDCA"), the Public
Health Service Act ("PHS") or similar foreign Governmental Entity or Law that is
manufactured, tested, distributed, held, and/or marketed by the Company or any
of its Subsidiaries is being manufactured, tested, distributed, held and
marketed in compliance in all material respects with all applicable requirements
under the FDCA or such similar Law of any foreign jurisdiction including, but
not limited to, those relating to investigational use, premarket clearance, good
manufacturing practices, labeling, advertising, promotional activities, record
keeping, filing of reports and security.

            (e) To the Knowledge of the Company, the Company has, prior to the
execution of this Agreement, provided to Parent copies of all documents in their
respective or any of its Subsidiaries' possession material to assessing
compliance with the FDCA and its implementing regulations and the PHS, 483s and
untitled letters, including, but not limited to, copies of (i) all warning
letters, notices of adverse findings and similar correspondence received in the
last two years, (ii) all audit reports performed during the last two years, and
(iii) any document concerning any significant oral or written communication
received from the FDA in the last two years.

            (f) To the Knowledge of the Company, the Company and its
Subsidiaries are not, and have not been, in violation of the Federal
Anti-Kickback Act, any Federal conspiracy statutes, the Prescription Drug
Marketing Act, Federal False Claims Act, Federal Stark Law or any other Federal
or state statute related to sales and marketing practices of pharmaceutical
manufacturers and others involved in the purchase and sale of pharmaceutical
products.

            (g) To the Knowledge of the Company, the Company and its
Subsidiaries have at all times complied with their respective obligations to
report accurate pricing information for its pharmaceutical products to the
government and to pricing services relied upon by the government and other
payors for pharmaceutical products, including without limitation its obligation
to report accurate "Fees and Price" under the Medicaid Rebate Statute and
accurate Average Wholesale Price.

            (h) To the Knowledge of the Company, neither the Company nor any of
its Subsidiaries has engaged in an unlawful or unauthorized practice of medicine
or other professionally licensed activities through any web sites sponsored or
operated, or formerly sponsored or operated, by the Company or any of its
Subsidiaries.

                                       17


     3.9    TITLE TO PROPERTY. The Company and each of its Subsidiaries have all
assets, properties, rights and contracts necessary to permit the Company and its
Subsidiaries to conduct their business as it is currently being conducted,
except where the failure to have such assets, properties, rights and contracts
would not be reasonably likely to have a Material Adverse Effect on the Company
and its Subsidiaries taken as a whole. The Company and each of its Subsidiaries
has good and marketable title to all of its properties, interests in properties
and assets, real and personal, reflected in the Company Balance Sheet (except
properties, interests in properties and assets sold or otherwise disposed of
since the Company Balance Sheet Date in the ordinary course of business
consistent with past practice), or with respect to leased properties and assets,
valid leasehold interests in, free and clear of all Liens, except (i) Liens for
current taxes not yet due and payable, (ii) such imperfections of title, Liens
and easements as do not and will not materially detract from or interfere with
the use or value of the properties subject thereto or affected thereby, or
otherwise materially impair business operations involving such properties and
(iii) Liens securing debt which are reflected on the Company Balance Sheet;
provided, however, that no representation is made in this section with respect
to infringement of third party Intellectual Property Rights. The property and
equipment of the Company and each of its Subsidiaries that are used in the
operations of business are (taken as a whole) in good operating condition and
repair, subject to normal wear and tear.

     3.10   TECHNOLOGY AND INTELLECTUAL PROPERTY.

            (a) DEFINITIONS. The following terms shall have the meanings set
forth below.

            "COMPANY INTELLECTUAL PROPERTY RIGHTS" means all rights in the
Significant Company IP and the Company's Trade Secrets and all other material
intellectual property rights in the Company Technology, Company Copyrights and
Company Trademarks, other than third party Intellectual Property Rights.

            "COMPANY TECHNOLOGY" means all Technology acquired by, or developed
by or for, the Company, and used in the business of the Company as currently
conducted.

            "COMPANY TRADEMARKS" means all Trademarks owned by the Company and
used in the business of the Company as currently conducted.

            "COMPUTER SOFTWARE" means all computer programs (whether in source
code or object code form), databases, compilations and documentation (including,
without limitation, user, operator, and training manuals) related to the
foregoing.

            "COPYRIGHTS" means U.S. and foreign copyrights (whether registered
or unregistered).

            "INTELLECTUAL PROPERTY RIGHTS" means all rights under Copyrights,
Patents, Trade Secrets, and Trademarks.

            "LICENSE AGREEMENTS" means all agreements to which the Company is a
party or otherwise bound, under which the Company is granting or is granted any
Intellectual Property Right.

                                       18


            "PATENTS" means all U.S. and foreign patents and patent
applications.

            "SIGNIFICANT COMPANY IP" means all: (i) Patents, (ii) registered
Copyrights and Copyright applications, and (iii) registered Trademarks and
Trademark applications, in which the Company has an ownership interest.

            "TECHNOLOGY" means all processes, formulae, algorithms, data,
models, plans, methodologies, theories, ideas, techniques, discoveries,
disclosures, inventions, Computer Software, information or know-how.

            "TRADEMARKS" means all U.S. and foreign trademarks, service marks,
trade names, designs, logos, slogans, internet domain names and general
intangibles of like nature (whether registered or unregistered).

            "TRADE SECRETS" means trade secrets as defined in the Uniform Trade
Secrets Act.

            (b) Section 3.10(b) of the Company Disclosure Letter is a list of
the material Significant Company IP (including for each, the applicable
jurisdiction, registration number (or application number) and date issued (or
date filed)) and the Company or a Subsidiary thereof is listed in the records of
the appropriate U.S. or foreign agency as the sole owner of record for each such
item of Significant Company IP.

            (c) To the Knowledge of the Company, the Company (i) owns all right,
title and interest in and to the material Significant Company IP and (ii) owns
all other material intellectual property rights in the Company Technology and
the Company's Copyrights, in each case free and clear of all Liens. To the
Knowledge of the Company, all employees or consultants who contributed to the
conception, discovery or development of any of the Company's Intellectual
Property Rights did so either (a) within the scope of his or her employment such
that, in accordance with applicable law, all Intellectual Property Rights
arising therefrom became the exclusive property of the Company, or (b) pursuant
to written agreements assigning all such Intellectual Property Rights to the
Company.

            (d) The Significant Company IP is subsisting, in full force and
effect, and has not been cancelled, expired or abandoned, except where any such
cancellation, expiration or abandonment, or any other failure to maintain in
force, resulted from the exercise of sound business judgment by the Company. To
the Knowledge of the Company, the Company Intellectual Property Rights are valid
and enforceable.

            (e) Section 3.10(e) of the Company Disclosure Letter sets forth a
true and complete list of all material License Agreements, other than end-user
license agreements for software applications that are commercially available.

            (f) Except as set forth in the Company SEC Reports, (i) to the
Knowledge of the Company, the conduct of the business of the Company or its
Subsidiaries as currently conducted or planned to be conducted does not infringe
any third party Intellectual Property Rights and (ii) the Company has no
Knowledge that any third party is infringing, diluting or violating any Company
Intellectual Property Rights and the Company has not brought any claims, suits,

                                       19


arbitrations or other adversarial proceedings related to the foregoing against
any third party, except as set forth in the Company SEC Reports.

            (g) Except as set forth in the Company SEC Reports, there is no
pending or, to the Knowledge of the Company, threatened claim, suit, arbitration
or other adversarial proceeding before any court, agency, arbitral tribunal, or
registration authority in any jurisdiction: (i) involving the Company
Intellectual Property Rights; (ii) alleging that the conduct of the business of
the Company or any of its Subsidiaries infringes any Intellectual Property
Rights of a third party; or (iii) challenging the ownership, use, validity,
enforceability or registrability of any Company Intellectual Property Rights.

            (h) Except as set forth in the Company SEC Reports, there are no
settlements, forbearances to sue, consents, judgments, or orders, other than the
License Agreements, that: (i) restrict any Company Intellectual Property Rights
in any material respect or; (ii) restrict the conduct of the business of the
Company in any material respect; or (iii) grant third parties any material
rights under Company Intellectual Property Rights.

            (i) To the Knowledge of the Company, no material Trade Secret of the
Company has been disclosed or authorized to be disclosed to any third party in
violation of confidentiality obligations to the Company, or its Subsidiaries
taken as a whole, and no party to a nondisclosure agreement with the Company is
in breach or default thereof. The Company has taken reasonable measures,
consistent with customary industry practice, to protect and preserve its Trade
Secrets.

            (j) No current or former director, officer, consultant or employee
of the Company will, after giving effect to the Transactions, own any of the
Company Intellectual Property Rights.

            (k) The execution of, the delivery of, the consummation of the
Transactions contemplated by, and the performance of the Company's obligations
under this Agreement will not result in any material loss or material impairment
of the Company Intellectual Property Rights or any material Intellectual
Property Rights licensed to the Company.

     3.11   ENVIRONMENTAL MATTERS. To the Knowledge of the Company, (a) the
Company and its Subsidiaries are in compliance in all material respects with
Federal, state, local and foreign laws and regulations governing pollution or
protection of human health or the environment, including laws and regulations
governing emissions, discharges, releases or threatened releases of toxic or
hazardous substances, materials or wastes, petroleum and petroleum products,
asbestos or asbestos-containing materials, radioactive materials,
polychlorinated biphenyls, radon, or lead or lead-based paints or materials
("MATERIALS OF ENVIRONMENTAL CONCERN"), or otherwise governing the generation,
storage, containment (whether above ground or underground), disposal, transport
or handling of Materials of Environmental Concern (collectively, "ENVIRONMENTAL
LAWS"), and including compliance with any permits or other governmental
authorizations or the terms and conditions thereof; (b) neither the Company nor
any of its Subsidiaries has received any written communication or notice, from a
Governmental Authority, alleging any violation of or noncompliance with any
Environmental Laws by the Company or any of its Subsidiaries and there is no
pending or threatened written claim, action, investigation or notice
(collectively, "ENVIRONMENTAL CLAIMS"), by any third party

                                       20


alleging liability for investigatory, cleanup or governmental response costs, or
natural resources or property damages, or personal injuries, attorney's fees or
penalties arising from (i) the presence, or release into the environment, of any
Materials of Environmental Concern at any location owned, leased or operated by
the Company or its Subsidiaries, or (ii) any violation, or alleged violation, of
any Environmental Law; and (c) neither the Company nor any of its Subsidiaries
has caused any "release" of a Material of Environmental Concern, as that term is
defined in the Comprehensive Environmental Response, Compensation, and Liability
Act, 42 U.S.C. Section 9601 ET SEQ., in a reportable quantity on any real
property owned or leased by the Company or any of its Subsidiaries. To the
Knowledge of the Company, the Company has made available to Parent all material
environmental site assessments, reports, results of investigations or audits
that are in the possession of the Company regarding environmental matters
pertaining to the environmental condition of the business of the Company and its
Subsidiaries, or the compliance (or noncompliance) by the Company or its
Subsidiaries with any Environmental Laws.

     3.12   TAXES.

                  (a)   The Company and each of its Subsidiaries has timely
filed (or has had timely filed on its behalf) with the appropriate Tax
Authorities all material Tax Returns required to be filed by the Company and
each of its Subsidiaries, and such Tax Returns are complete in all material
respects.

                  (b)   The Company and each of its Subsidiaries has paid, or
where payment is not yet due, has established an adequate accrual in accordance
with GAAP for the payment of, all material Taxes for all periods ending through
the date hereof. The Company and each of its Subsidiaries has deducted, withheld
or timely paid (or had deducted, withheld or timely paid on its behalf) to the
appropriate governmental authority all material amounts required to be deducted,
withheld or paid in connection with amounts paid or owing to any employee,
independent contractor, creditor, stockholder or any other third party.

                  (c)   There are no Liens for Taxes upon any property or assets
of the Company or any of its Subsidiaries, except for Taxes not yet due or for
which adequate reserves (excluding any "deferred taxes" or similar items that
reflect timing differences between tax and financial accounting principals) have
been established in accordance with GAAP.

                  (d)   No Federal, state, local or foreign Audits are presently
pending with regard to any Taxes or Tax Returns of the Company and its
Subsidiaries and to the Knowledge of the Company, no such Audit is threatened.

                  (e)   There are no outstanding requests, agreements, consents
or waivers to extend the statutory period of limitations applicable to the
assessment of any Taxes or deficiencies against the Company or any of its
Subsidiaries, and no power of attorney granted by the Company or any of its
Subsidiaries with respect to any Taxes is currently in force.

                  (f)   Neither the Company nor any of its Subsidiaries is a
party to any agreement providing for the allocation, indemnification, or sharing
of Taxes that shall remain in force following the Effective Time.

                                       21


                  (g)   Neither the Company nor any of its Subsidiaries is or
has been a U.S. real property holding company (as defined in Section 897(c)(2)
of the Code) during the applicable period specified in Section 897(c)(1)(A)(ii)
of the Code.

                  (h)   Neither the Company nor any of its Subsidiaries has been
a member of any "affiliated group" (as defined in Section 1504(a) of the Code)
(other than a group the common parent of which was the Company) and neither the
Company nor any of its Subsidiaries is liable for the Taxes of another person
(other than the Company or any of its Subsidiaries) under Treas. Reg. 1.1502-6,
as a transferee or successor, by contract or otherwise, for any period.

                  (i)   Neither the Company nor any of its Subsidiaries has
distributed stock of another corporation, or has had its stock distributed by
another corporation, in a transaction that was governed, or purported or
intended to be governed, in whole or in part, by Code Section 355 or 361.

                  (j)   Neither the Company nor any of its Subsidiaries has
undergone, or will undergo prior to the Closing Date a change in its method of
accounting resulting in an adjustment to its taxable income or loss pursuant to
Section 481 of the Code.

                  (k)   The United States Federal and state "net operating loss"
of the Company and its Subsidiaries through the date of the last filed
applicable Tax Return is set forth on Section 3.12(k) of the Company Disclosure
Letter.

                  (l)   Within ten (10) business days of the date hereof, the
Company will make available to Parent: (i) complete and correct copies of all
United States Federal and state income Tax Returns, examination reports and
statements of deficiencies assessed against or agreed to by the Company or any
of its Subsidiaries with respect to the prior four (4) taxable years filed; and
(ii) a written schedule of foreign countries in which the Company and its
Subsidiaries has or has had since 1998 a permanent establishment, as defined in
any applicable Tax treaty or convention between the United States and such
foreign country.

                  (m)   "AUDIT" means any audit, assessment, or other
examination relating to Taxes by any Tax Authority or any judicial or
administrative proceedings relating to Taxes. "TAX" or "TAXES" means all
Federal, state, local, and foreign taxes (including without limitation any
provincial income, gross receipts, property, sales, use, license, excise,
franchise, employment, payroll, alternative or add-on minimum, ad valorem,
transfer or excise tax, or any other tax, custom, duty or governmental fee), and
other assessments of a similar nature (whether imposed directly or through
withholding), including any interest, additions to tax, or penalties applicable
thereto, imposed by any Tax Authority. "TAX AUTHORITY" means the IRS and any
other domestic or foreign governmental authority responsible for the
administration of any Taxes. "TAX RETURNS" mean all Federal, state, local, and
foreign tax returns, declarations, statements, reports, schedules, forms, and
information returns and any amendments thereto.

     3.13   EMPLOYEE BENEFIT PLANS.

                  (a)   Section 3.13(a) of the Company Disclosure Letter
contains a list of the material employment, bonus, deferred compensation,
incentive compensation, stock purchase, stock option, stock appreciation right
or other stock-based incentive, severance,

                                       22


change-in-control, or termination pay, hospitalization or other medical,
disability, life or other insurance, supplemental unemployment benefits,
profit-sharing, welfare, pension, or retirement plan, program, agreement or
arrangement (whether or not reduced to writing) and each other employee benefit
plan, program, agreement or arrangement which is maintained by the Company or
any of its Subsidiaries, or by any trade or business, whether or not
incorporated (an "ERISA AFFILIATE"), that together with the Company or any of
its Subsidiaries would be deemed a "single employer" within the meaning of
Section 4001(b)(1) of the Employee Retirement Income Security Act of 1974, as
amended ("ERISA"), for the benefit of any current or former employee of, or
consultant or advisor to, the Company or any of its Subsidiaries (the "COMPANY
EMPLOYEE PLANS").

                  (b)   The Company has made available to Parent a copy of each
of the Company Employee Plans that has been reduced to writing, and a completed
and accurate summary of all material terms of each Company Employee Plan that
has not been reduced to writing, and related plan documents, together with all
amendments, (including trust documents, insurance policies or contracts,
employee booklets, summary plan descriptions and other authorizing documents,
and any material employee communications relating thereto) and has, with respect
to each Company Employee Plan which is subject to ERISA reporting requirements,
made available copies of the Form 5500 reports filed for the last three (3) plan
years. Any Company Employee Plan intended to be qualified under Section 401(a)
or 501(c)(9) of the Code has a currently valid favorable determination letter
from the IRS as to its qualified status or is within the remedial amendment
period for making any changes or has been established under a standardized
prototype plan for which a currently valid IRS opinion letter has been obtained
by the plan sponsor. The Company has also made available to Parent the most
recent IRS determination, notification, advisory, or opinion letter issued with
respect to each such Company Employee Plan. Each Company Employee Plan that is
intended to be qualified under Section 401(a) of the Code is so qualified and
each trust that is intended to be exempt under Section 501(a)(9) of the Code is
so exempt. All Form 5500 reports required to be filed have been timely filed and
to the Company's Knowledge, there are no unresolved disputes related thereto.

                  (c)   There has been no "prohibited transaction," as such term
is defined in Section 406 of ERISA and Section 4975 of the Code, with respect to
any Company Employee Plan, except "prohibited transactions" that would not
result in a material liability of the Company under the Code. Each Company
Employee Plan has been administered in all material respects in accordance with
its terms and in compliance with the requirements prescribed by any and all
statutes, rules and regulations (including ERISA and the Code). The Company and
each of its Subsidiaries or ERISA Affiliates have timely and properly performed
all obligations required to be performed by them under, are not in any material
respect in default under or violation of, and have no Knowledge of any material
default or violation by any other party to, any of the Company Employee Plans.
All contributions and premiums required to be made or paid by the Company or any
of its Subsidiaries to any Company Employee Plan have been made or paid on or
before their due dates. No suit, administrative proceeding, action or other
litigation has been brought, or to the Knowledge of the Company is threatened,
against or with respect to any such Company Employee Plan, including any audit
or inquiry by the Internal Revenue Service (the "IRS") or United States
Department of Labor other than requests for payments in the ordinary course or
requests for qualified domestic relations orders. No Lien has been imposed under

                                       23


Section 412(n) of the Code or Section 302(f) of ERISA on the assets of the
Company or any of its Subsidiaries.

                  (d)   No Company Employee Plan provides benefits, including
without limitation death or medical benefits (whether or not insured), with
respect to current or former employees of the Company, its Subsidiaries or any
ERISA Affiliate after retirement or other termination of service (other than (i)
coverage mandated by applicable laws, (ii) death benefits or retirement benefits
under any "employee pension plan," as that term is defined in Section 3(2) of
ERISA or (iii) deferred compensation benefits accrued as liabilities on the
books of the Company, any of its Subsidiaries or an ERISA Affiliate).

                  (e)   Neither the Company nor any of its Subsidiaries or any
ERISA Affiliate currently maintains, sponsors, participates in or contributes
to, or has ever maintained, sponsored, participated in or contributed to any
pension plan (within the meaning of Section 3(2) of ERISA) which is subject to
Part 3 of Subtitle B of Title I of ERISA, Title IV of ERISA or Section 412 of
the Code.

                  (f)   Neither the Company nor any of its Subsidiaries or any
ERISA Affiliate is, or has ever been, a party to or contributes to or has ever
been required to contribute to any "multi-employer plan" as defined in Section
3(37) of ERISA or any plan that has two or more contributing sponsors at least
two of whom are not under common control, within the meaning of Section 4063(a)
of ERISA.

                  (g)   Neither the Company nor any of its Subsidiaries or any
ERISA Affiliate maintains, sponsors, participates in or contributes to any (i)
Multiple Employer Welfare Arrangements, (ii) any Voluntary Employee Beneficiary
Associations within the meaning of Section 501(c)(9) of the Code or (iii) any
welfare benefit funds within the meaning of Section 419(e) of the Code.

                  (h)   Except for restrictions imposed by applicable law and
contractual undertakings set forth in the Company Employee Plan documents to the
extent they mirror such restrictions, each United States Company Employee Plan
and, to the Knowledge of the Company, each foreign Company Employee Plan may be
terminated or amended at any time without the consent of any participant, former
participant, or beneficiary. Neither the Company nor any of its Subsidiaries has
made any payments, or has been or is a party to any agreement, contract,
arrangement or plan that could result in it making payments, that have resulted
or would result, separately or in the aggregate, in the payment of any "excess
parachute payment" within the meaning of Code Section 280G or in the imposition
of an excise Tax under Code Section 4999 (or any corresponding provisions of
state, local or foreign Tax law) or that were not or would not be deductible
under Code Sections 162 or 404.

                  (i)   Except as provided in this Agreement, no employee of,
consultant to, or other provider of services to the Company or any of its ERISA
Affiliates will be entitled to any additional benefit or the acceleration of the
payment or vesting of any benefit under any Company Employee Plan by reason of
the transactions contemplated by this Agreement.

                                       24


                  (j)   Neither the Company nor any of its Subsidiaries has any
"leased employees" within the meaning of Section 414(m) of the Code or any
independent contractors or other individuals who provide employee-type services
but who are not recognized by the Company as employees of the Company.

     3.14   LABOR MATTERS. Each of the Company and its Subsidiaries is in
compliance in all material respects with all currently applicable laws and
regulations respecting, terms and conditions of employment, wages, hours and
occupational safety and health and employment practices, and, to the Knowledge
of the Company, is not engaged in any unfair labor practice. As of the date
hereof, neither the Company nor any of its Subsidiaries has received written
notice of any charge or complaint against the Company or any of its Subsidiaries
pending before the Equal Employment Opportunity Commission, the National Labor
Relations Board, or any other Governmental Entity regarding an unlawful
employment practice. To the Knowledge of the Company as of the date hereof, no
Governmental Entity responsible for the enforcement of labor or employment laws
intends to conduct an investigation with respect to or relating to the Company
or any of its Subsidiaries and no such investigation is in progress. Each of the
Company and its Subsidiaries has in all material respects withheld all amounts
required by law or by agreement to be withheld from the wages, salaries, and
other payments to employees and, to the Knowledge of the Company, is not liable
for any material arrears of wages or any taxes or any penalty for failure to
comply with any of the foregoing. To the Knowledge of the Company, as of the
date hereof, there are no complaints, lawsuits, arbitrations or other actions
pending or threatened in writing between the Company or any of its Subsidiaries
and any of their respective employees or former employees. Neither the Company
nor any of its Subsidiaries is a party to any collective bargaining agreement or
other labor union contract nor does the Company know of any activities or
proceedings of any labor union to organize any such employees. There is no labor
strike, slowdown or stoppage actually pending or, to the Knowledge of the
Company, threatened against or affecting the Company or any of its Subsidiaries.
The Company and each of its Subsidiaries are and have been in substantial
compliance with all notice and other requirements of the Worker Adjustment and
Retaining Notification Act (the "WARN ACT") and any similar state or local
statute. No employee of the Company or any Subsidiary has suffered an
"employment loss" (as defined in the WARN Act) during the ninety (90)-day period
prior to the execution of this Agreement.

     3.15   INSURANCE. Section 3.15 of the Company Disclosure Letter contains a
complete list of the material policies and contracts of insurance maintained by
the Company and each of its Subsidiaries. There is no material claim pending
under any of such policies or bonds as to which coverage has been questioned,
denied or disputed by the underwriters of such policies or bonds. All premiums
due and payable to date under all such policies and bonds have been paid and the
Company and each of its Subsidiaries is otherwise in compliance in all material
respects with the terms of such policies and bonds. The Company has not been
notified of any threatened termination of, or material premium increase with
respect to, any of such policies.

     3.16   COMPLIANCE WITH LAWS. Except as disclosed in the Company SEC
Reports, each of the Company and its Subsidiaries has complied in all material
respects with, is not in violation of, and has not received any notices of
violation with respect to, any material federal, state, local or foreign
statute, law or regulation with respect to the conduct of its business, or the
ownership or operation of its business.

                                       25


     3.17   BROKERS' AND FINDERS' FEES. No agent, broker, investment banker,
financial advisor or other firm or person is or will be entitled to any brokers'
or finders' fee or any other commission or similar fee from the Company in
connection with any of the Transactions except for Merrill Lynch & Co. Inc.,
whose fees and expenses will be paid by the Company in accordance with its
agreement with such firm. The Company has previously provided Parent with a copy
of Merrill Lynch & Co. Inc.'s engagement letter.

     3.18   STATE TAKEOVER STATUTES. The action taken by the Company Board of
Directors constitutes approval of the Transactions by the Company Board of
Directors under Section 203 of the DGCL, and, no "fair price," "control share
acquisition," "business combination" or other similar state takeover statute is
applicable to the Transactions or the execution, delivery or performance of this
Agreement.

     3.19   BOARD APPROVAL. The Company's Board of Directors, at a meeting duly
called and held at which all directors were present, has (i) duly and validly
approved and taken all corporate action required to be taken by the Company
Board of Directors to authorize this Agreement and the consummation of the
Transactions, (ii) resolved that the Transactions are advisable and in the best
interests of the stockholders of the Company and that the consideration to be
paid for each Share in the Offer and the Merger is fair to the holders of such
Shares, (iii) subject to the other terms and conditions of this Agreement,
resolved to recommend that the stockholders of the Company accept the Offer,
tender their Shares to the Purchaser pursuant to the Offer, and approve and
adopt this Agreement and each of the Transactions, and (iv) resolved that the
foregoing resolutions are sufficient to prevent Section 11(a) of any Indemnity
Agreement (as defined in Section 3.19) from becoming applicable to the Agreement
or the Transactions and that the creation of any trust upon the request of any
Agent (as defined in the Indemnity Agreement) pursuant to Section 11(b) of any
Indemnity Agreement would not be in the best interests of the Company and that
no such trust has been created, and none of the aforesaid actions by the Company
Board of Directors has been amended, rescinded or modified

     3.20   VOTE REQUIRED. The affirmative vote of the holders of a majority of
the outstanding shares of Company Common Stock is the only vote of the holders
of any of the Company Capital Stock necessary to approve this Agreement and the
Transactions and is only necessary in the event that the number of shares of
Company Common Stock tendered pursuant to the Offer represents less than ninety
percent (90%) of the issued and outstanding shares of Company Common Stock.

     3.21   MATERIAL CONTRACTS AND OTHER AGREEMENTS.

            (a) Each of the Company and its Subsidiaries has in all material
respects performed the obligations required to be performed by it (except for
past breaches which have been cured or waived or for which the Company and its
Subsidiaries have no continuing obligations) and is entitled to all benefits
under, and to its Knowledge, is not alleged to be in default in respect of, any
Material Contract except for such non-performance or default as would not
reasonably be likely to have a Material Adverse Effect. Each of the Material
Contracts is valid, subsisting in full force and effect, binding upon the
Company or its applicable Subsidiary, and, to the Knowledge of the Company,
binding upon the other parties thereto in accordance with their terms, and the
Company and its Subsidiaries there exists no material default or event

                                       26


of default or material event, occurrence, condition or act, with respect to the
Company or any of its Subsidiaries or, to the Knowledge of the Company with
respect to the other contracting party, which, with the giving of notice, the
lapse of time or the happening of any other event or conditions, would
reasonably be expected to become a default or event of default under the terms
of any Material Contract except for such defects, defaults, events, occurrences,
conditions or acts or other events as would not reasonably be likely to have a
Material Adverse Effect. Section 3.21 of the Company Disclosure Letter contains
a list of any person who is party to an Indemnity Agreement with the Company
entered into during the two (2) years preceding the date hereof in substantially
the form of Exhibit 10.2 of the Company's Form 10-K for the fiscal year ended
December 31, 2002 (each an "INDEMNITY AGREEMENT") or similar agreement.

            (b) Other than those contracts disclosed in the Company SEC Reports
filed prior to the date of this Agreement, neither the Company nor any of its
Subsidiaries is a party to any agreement that materially limits or restricts the
Company, any of its Subsidiaries or any of their affiliates or successors in
competing or engaging in any line of business, in any therapeutic area, in any
geographic area or with any person.

            (c) Other than those contracts disclosed in the Company SEC Reports
filed prior to the date of this Agreement, neither the Company nor any of its
Subsidiaries is a party to any agreement involving a personal loan to a director
or officer;

            (d) Neither the Company nor any of its Subsidiaries is a party to
any agreement obligating the Company to file a registration statement under the
Securities Act which filing has not yet been made.

            (e) To the Knowledge of the Company, no executive officer or
director of the Company has (whether directly or indirectly through another
entity in which such person has a material interest, other than as the holder of
less than 2% of a class of securities of a publicly traded company) any material
interest in any property or assets of the Company (except as a stockholder) or
any of its Subsidiaries, any competitor, customer, supplier or agent of the
Company or any of its Subsidiaries or any person that is currently a party to
any Material Contract or agreement with the Company or any of its Subsidiaries.

            (f) Neither the Company nor any of its Subsidiaries is a party to
any interest rate, equity or other swap or derivative instrument.

     3.22   INFORMATION IN THE PROXY STATEMENT. The Proxy Statement if any (and
any amendment thereof and supplement thereto) at the date mailed to the
Company's stockholders and at the time of any meeting of Company stockholders to
be held in connection with the Merger, will not contain any untrue statement of
a material fact or omit to state any material fact required to be stated therein
or necessary in order to make the statements therein, in light of the
circumstances under which they are made, not misleading, except that no
representation is made by the Company with respect to statements made therein
based on information supplied in writing by Parent or Purchaser expressly for
inclusion in the Proxy Statement. The Proxy Statement, as to information
supplied by the Company for inclusion therein, will comply in all material
respects with the provisions of the Exchange Act and the rules and regulations
thereunder.

                                       27


     3.23   INFORMATION IN THE OFFER DOCUMENTS AND THE SCHEDULE 14D-9. The
information supplied by the Company expressly for inclusion or incorporation by
reference in the Offer Documents or the Schedule 14D-9 will not contain any
untrue statement of a material fact or omit to state any material fact required
to be stated therein or necessary in order to make the statements made therein,
in the light of the circumstances under which they were made, not misleading.
The Schedule 14D-9 will comply in all material respects with the provisions of
applicable federal securities laws and, on the date filed with the SEC and on
the date first published or sent or given to the Company's stockholders, will
not contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary in order to make the
statements made therein, in the light of the circumstances under which they were
made, not misleading, except that the Company makes no representation or
warranty with respect to statements made in the Schedule 14D-9 based on
information furnished by Parent or Purchaser expressly for inclusion therein.

     3.24   OPINION OF FINANCIAL ADVISOR. The Company has received the written
opinion of Merrill Lynch & Co. Inc. dated the date hereof, to the effect that,
as of such date, the consideration to be received in the Offer and the Merger by
the Company's stockholders is fair to the Company's stockholders from a
financial point of view, a signed copy of which has been delivered to the
Company.

     3.25   RIGHTS PLAN. The Company Board of Directors has taken such action as
is necessary with respect to the Company Rights Agreement such that the
execution and delivery of this Agreement and the consummation of the
Transactions will not (i) result in Parent becoming an "Acquiring Person" under
the Rights Agreement, or (ii) result in the grant of any rights to any person
under the Rights Agreement or enable or require the preferred stock purchase
rights under the Rights Agreement to be exercised, distributed or triggered.

     3.26   NO DEFAULT. The business of the Company and each of its Subsidiaries
has not been and is not being conducted in default or violation of any term,
condition or provision of (i) its respective certificate of incorporation or
bylaws or similar organizational documents, or (ii) any Federal, state, local or
foreign law, statute, regulation, rule, ordinance, judgment, decree, order,
writ, injunction, concession, grant, franchise, permit or license or other
governmental authorization or approval applicable to the Company or any of its
Subsidiaries or relating to any of the property owned, leased or used by them,
or applicable to their business, excluding, with respect to clause (ii),
defaults or violations that, individually or in the aggregate, would not be
reasonably likely to have a Material Adverse Effect on the Company and its
Subsidiaries taken as a whole or materially impair the ability of the Company to
consummate the Transactions. No investigation or review by any Governmental
Entity or other entity with respect to the Company or any of its Subsidiaries is
pending or, to the Knowledge of the Company, threatened, nor has any
Governmental Entity or other entity indicated an intention to conduct such an
investigation or review, other than those that individually or in the aggregate
would not be reasonably likely to have a Material Adverse Effect on the Company
and its Subsidiaries taken as a whole.

     3.27   PRODUCT LIABILITY. There are not presently pending or, to the
Knowledge of the Company, threatened any civil, criminal or administrative
actions, suits, demands, claims, hearings, notices of violation, investigations,
proceedings or demand letters relating to any alleged hazard or alleged defect
in design, manufacture, materials or workmanship, including

                                       28


any failure to warn or alleged breach of express or implied warranty or
representation, relating to any product manufactured, distributed or sold by or
on behalf of the Company and its Subsidiaries, which if adversely determined,
would or would not be reasonably likely to have a Material Adverse Effect on the
Company and its Subsidiaries taken as a whole.

     3.28   COMMERCIAL RELATIONSHIPS. Since the Company Balance Sheet Date, none
of the Company's or its Subsidiaries' material suppliers, collaborators,
distributors, manufacturers, licensors and licensees has canceled or otherwise
terminated its relationship with the Company or any of its Subsidiaries or
altered its relationship with the Company or any of its Subsidiaries, except
where such cancellation or termination or alteration would not be reasonably
likely to have a Material Adverse Effect on the Company and its Subsidiaries
taken as a whole. Since the Balance Sheet Date, to the Knowledge of the Company,
the Company has not received any written threat or notice from any such entity,
to terminate, cancel or otherwise materially modify its relationship with the
Company or any of its Subsidiaries, except where such cancellation, termination
or modification would not be reasonably likely to have a Material Adverse Effect
on the Company and its Subsidiaries taken as a whole.

     3.29   THERAPEUTIC HUMAN POLYCLONALS, INC.. To the Company's Knowledge,
except as set forth in the disclosure schedule to the Therapeutic Human
Polyclonals, Inc., Series A-2 and Series B Preferred Stock Purchase Agreement,
dated November 8, 2002, by and among Therapeutic Human Polyclonals, Inc.,
SangStat Medical Corporation and Research Corporation Technologies, Inc. (the
"THP AGREEMENT") as of the date hereof: (i) THP owns or possesses sufficient
legal rights to all patents, trademarks, service marks, trade names, copyrights,
trade secrets, licenses, information and other proprietary rights and processes
necessary for its business as conducted; (ii) THP has all franchises, permits,
licenses and any similar governmental or quasi-governmental authority necessary
for the conduct of its business as conducted, the lack of which could materially
and adversely affect the business properties, prospects or financial condition
of THP; and (iii) THP is, and has at all times since its inception been, in
compliance with all applicable laws, except where a failure to comply with such
laws has not had and is not reasonably expected to have, a Material Adverse
Effect on THP.

                                   ARTICLE IV

             REPRESENTATIONS AND WARRANTIES OF PARENT AND PURCHASER

            Each of Parent and Purchaser represents and warrants to the Company
as follows:

     4.1    ORGANIZATION, STANDING AND POWER. Each of Parent and Purchaser is a
corporation duly organized, validly existing and in good standing under the laws
of its jurisdiction of organization. Each of Parent and Purchaser has the
corporate power to own its properties and to carry on its business as now being
conducted and is duly qualified to do business and is in good standing in each
jurisdiction in which the failure to be so qualified and in good standing would
have a Material Adverse Effect on such party. Neither Parent nor Purchaser is in
violation of any of the provisions of its Articles of Organization or Bylaws.

                                       29


     4.2    AUTHORITY; NONCONTRAVENTION. Each of Parent and Purchaser has all
requisite corporate power and authority to enter into this Agreement and to
consummate the Transactions. The execution and delivery of this Agreement and
the consummation of the Transactions have been duly authorized by all necessary
corporate action on the part of Parent and Purchaser. This Agreement has been
duly executed and delivered by each of Parent and Purchaser and, assuming this
Agreement constitutes the valid and binding obligation of the other parties
hereto, constitutes the valid and binding obligation of each of Parent and
Purchaser enforceable against each of them in accordance with its terms, except
to the extent that enforceability may be limited by the effect, if any, of (i)
any applicable bankruptcy, reorganization, insolvency, moratorium or other laws
affecting the enforcement of creditors' rights generally, and (ii) general
principles of equity, regardless of whether such enforceability is considered in
a proceeding at law or in equity. The execution and delivery of this Agreement
does not, and the consummation of the Transactions will not, conflict with, or
result in any violation of, or default under (with or without notice or lapse of
time, or both), or give rise to a right of termination, cancellation or
acceleration of any obligation or loss of a benefit under any provision of the
Articles of Organization or Bylaws of Parent or Purchaser. Except for (i)
compliance with any applicable requirements of the Exchange Act, (ii) any filing
pursuant to the DGCL, (iii) the filing or deemed filing with the SEC and/or
Nasdaq of (A) the Schedule TO, (B) the Proxy Statement, if stockholder approval
is required by law and (C) such reports under Section 13(a), 13(d) and Section
16 of the Exchange Act as may be required in connection with this Agreement and
the Transactions, (iv) such filings and approvals as may be required by any
applicable state securities, blue sky or takeover laws, (v) filings, clearances,
permits, authorizations, consents and approvals as may be required under the HSR
Act and any comparable provisions under any applicable pre-merger notification
laws or regulations of foreign jurisdictions, and (vi) such other consents,
authorizations, filings, approvals and registrations which are obtained prior to
Closing or if not obtained or made would not be material to Parent or Purchaser
or have a material effect on the ability of the parties hereto to consummate the
Merger, no notice to, filing with, and no permit, authorization, consent or
approval of, any Governmental Entity or any private third party is necessary for
the consummation by Parent and Purchaser of the Transactions.

     4.3    INFORMATION IN THE OFFER DOCUMENTS. The information supplied by
either of Parent or Purchaser expressly for inclusion or incorporation by
reference in the Offer Documents or the Schedule TO will not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary in order to make the statements made therein, in the
light of the circumstances under which they were made, not misleading. The
Schedule TO will comply in all material respects with the provisions of
applicable federal securities laws and, on the date filed with the SEC and on
the date first published or sent or given to the Company's stockholders, will
not contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary in order to make the
statements made therein, in the light of the circumstances under which they were
made, not misleading, except that neither of Parent or Purchaser makes any
representation or warranty with respect to statements made in the Schedule TO
based on information furnished by the Company expressly for inclusion therein.

     4.4    INFORMATION IN THE PROXY STATEMENT. The Proxy Statement, if any (and
any amendment thereof and supplement thereto), at the date mailed to the
Company's stockholders and at the time of any meeting of Company stockholders to
be held in connection with the

                                       30


Merger, will not contain any untrue statement of a material fact or omit to
state any material fact required to be stated therein or necessary in order to
make the statements therein, in light of the circumstances under which they are
made, not misleading, except that no representation is made by either of Parent
or Purchaser other than with respect to statements made therein based on
information supplied by the Company expressly for inclusion in the Proxy
Statement. The Proxy Statement, as to information supplied by either of Parent
or Purchaser for inclusion therein, will comply in all material respects with
the provisions of the Exchange Act and the rules and regulations thereunder.

     4.5    FINANCING. Purchaser has, and will have available to it upon the
consummation of the Offer, sufficient funds to consummate the Transactions
contemplated by this Agreement, including payment in full for all Shares validly
tendered into the Offer or outstanding at the Effective Time (and all related
fees and expenses), subject to the terms and conditions of the Offer and this
Agreement.

     4.6    OWNERSHIP OF COMPANY STOCK. On the date hereof, Parent and Purchaser
own no shares of Company Common Stock, and (other than as specifically provided
herein) own no additional rights to purchase Company Common Stock through any
option from any other person.

     4.7    LITIGATION. Except as set forth in the reports and documents
required to be filed by Parent with the SEC since January 1, 2003, there is no
judgment, decree or order against Parent or Purchaser, or any of their
respective subsidiaries or, to the knowledge of Parent or Purchaser, any of
their directors or officers (in their capacities as such), that would reasonably
be expected to prevent, enjoin or materially alter or delay any of the
Transactions.

     4.8    BROKERS' AND FINDERS' FEES. No agent, broker, investment banker,
financial advisor or other firm or person other than Credit Suisse First Boston
LLC is or will be entitled to any brokers' or finder's fee or any other
commission or similar fee from Parent in connection with any of the transactions
contemplated by this Agreement.

                                    ARTICLE V

                       CONDUCT PRIOR TO THE EFFECTIVE TIME

     5.1    CONDUCT OF BUSINESS BY THE COMPANY. During the period from the date
of this Agreement and continuing until the earlier of the termination of this
Agreement pursuant to its terms or the Effective Time, the Company and each of
its subsidiaries shall, except to the extent that Parent shall otherwise consent
in writing and except as otherwise expressly provided in this Agreement or in
Section 5.1 of the Company Disclosure Letter, carry on its business in the
usual, regular and ordinary course, substantially the same manner as heretofore
conducted and in compliance in all material respects with all applicable laws
and regulations, pay its debts and Taxes when due subject to good faith disputes
over such debts, and pay or perform other material obligations when due.

            Without limiting the generality of the foregoing, without the prior
written consent of Parent, during the period from the date of this Agreement and
continuing until the earlier of

                                       31


the termination of this Agreement pursuant to its terms or the Effective Time,
the Company shall not do any of the following and shall not permit its
subsidiaries to do any of the following, except as may be expressly contemplated
or specifically permitted by this Agreement or as set forth in Section 5.1 of
the Company Disclosure Letter:

            (a) Waive any stock repurchase rights, accelerate, amend or change
the period of exercisability of options or restricted stock, or reprice options
granted under any employee, consultant, director or other stock plans or
authorize cash payments in exchange for any options granted under any of such
plans;

            (b) Adopt a plan of complete or partial liquidation, dissolution,
merger, consolidation, restructuring, recapitalization or other reorganization
(other than the Merger);

            (c) Grant any severance or termination pay to any officer, director
or employee except pursuant to written agreements in effect, or policies
existing, on the date hereof or adopt any new or amend any existing severance,
retention or change in control plan;

            (d) Transfer or license to any person or entity or otherwise extend,
amend, modify, permit to lapse or fail to preserve any of the Company
Intellectual Property Rights material to the Company's business as presently
conducted or planned to be conducted, other than nonexclusive licenses in the
ordinary course of business consistent with past practice or disclose to any
person who has not entered into a confidentiality agreement any Trade Secrets;

            (e) Declare, set aside, or pay any dividends on or make any other
distributions (whether in cash, stock, equity securities or property) in respect
of any capital stock or split, combine or reclassify any capital stock or issue
or authorize the issuance of any other securities in respect of, in lieu of or
in substitution for any capital stock;

            (f) Purchase, redeem or otherwise acquire, directly or indirectly,
any shares of capital stock of the Company or its subsidiaries, or any
instrument or security that consists of a right to acquire such shares, except
repurchases of unvested shares at cost in connection with the termination of the
employment relationship with any employee pursuant to stock option or purchase
agreements in effect on the date hereof;

            (g) Issue, deliver, sell, authorize, pledge or otherwise encumber
any shares of capital stock or any securities convertible into or exchangeable
for shares of capital stock, or subscriptions, rights, warrants or options to
acquire any shares of capital stock or any securities convertible into
exchangeable for shares of capital stock, or enter into other agreements or
commitments of any character obligating it to issue any such shares or
convertible securities, other than the issuance, delivery and/or sale of shares
of the Company Common Stock pursuant to the exercise of stock options or
warrants therefor outstanding as of the date hereof in accordance with their
present terms;

            (h) Cause, permit or propose any amendments to its Certificate of
Incorporation, Bylaws or other charter documents (or similar governing
instruments of any of its subsidiaries);

            (i) Acquire or agree to acquire by merging or consolidating with, or
by purchasing any equity interest in or a portion of the assets of, or by any
other manner, any

                                       32


business or any corporation, partnership, association or other business
organization or division thereof; or otherwise acquire or agree to acquire any
assets which are material, individually or in the aggregate, to the business of
the Company; or enter into or amend any material joint ventures, strategic
partnerships or alliances;

            (j) Sell, transfer, lease, license, mortgage, pledge, encumber or
otherwise dispose of any properties or assets which are material, individually
or in the aggregate, to the business of the Company;

            (k) Incur or assume any indebtedness for borrowed money or guarantee
or otherwise become liable or responsible for (whether directly, contingently or
otherwise) any such indebtedness of another person, issue or sell any debt
securities or options, warrants, calls or other rights to acquire any debt
securities of the Company other than (i) in connection with the financing of
ordinary course trade payables consistent with past practice or (ii) pursuant to
existing credit facilities as in effect on the date hereof in the ordinary
course of business;

            (l) Adopt or amend any employee benefit plan or employee stock
purchase or employee stock option plan, or enter into or amend any employment
contract, consulting agreement or collective bargaining agreement (other than
offer letters and letter agreements entered into in the ordinary course of
business consistent with past practice and as may be required by applicable
Law), pay any special bonus or special remuneration to any director, officer or
employee, or increase the salaries or wage rates or fringe benefits (including
rights to severance or indemnification) of its directors, officers or employees
other than to non-officer employees in the ordinary course of business
consistent with past practice, or make any loans to any of its directors,
officers or employees, agents or consultants, or make any change in its existing
borrowing or lending arrangements for or on behalf of any of such persons
pursuant to an employee benefit plan or otherwise;

            (m) Pay or make any accrual or arrangement for payment of any
pension, retirement allowance or other employee benefit pursuant to any existing
plan, agreement or arrangement to any director or officer or pay or agree to pay
or make any accrual or arrangement for payment to any officers or directors of
the Company or any of its subsidiaries of any amount relating to unused vacation
days; adopt or pay, grant, issue, accelerate or accrue salary or other payments
or benefits pursuant to any pension, profit-sharing, bonus, extra compensation,
incentive, deferred compensation, stock purchase, stock option, stock
appreciation right, group insurance, severance pay, retirement or other employee
benefit plan, agreement or arrangement, or any employment or consulting
agreement with or for the benefit of any Company or Company subsidiary director
or officer, whether past or present, or amend in any material respect any such
existing plan, agreement or arrangement in a manner inconsistent with the
foregoing;

            (n) Modify, amend or terminate any Material Contract or agreement to
which the Company or any subsidiary thereof is a party, including any joint
venture agreement, or cancel any material debts or waive, release or assign any
material rights or claims thereunder;

            (o) Pay, discharge or satisfy any claims, liabilities or obligations
(whether absolute, accrued, contingent or otherwise), other than the payment,
discharge or satisfaction of

                                       33


any such claims, liabilities or obligations reflected or reserved against in, or
contemplated by, the consolidated financial statements (or the notes thereto) of
the Company and its subsidiaries;

            (p) Enter into any leases (including any amendments, extensions or
replacements of leases existing as of the date hereof) or any purchase,
acquisition licensing, distribution, collaboration, sponsorship, advertising or
other similar contracts, agreements, or obligations material to the Company;

            (q) Permit any material insurance policy naming it as a beneficiary
or a loss payee to be cancelled or terminated;

            (r) Revalue any of its assets or make any change in accounting
methods, principles or practices, except as required by GAAP;

            (s) Make or change any election relating to Taxes, adopt or change
any accounting method relating to Taxes, enter into any closing agreement
relating to Taxes, file any amended Tax Return, settle or consent to any claim
or assessment relating to Taxes, incur any obligation to make any payment of, or
in respect of, any Taxes, or agree to extend or waive the statutory period of
limitations for the assessment or collection of Taxes; or

            (t) Fail to notify and consult with Parent promptly (i) after
receipt of any material communication from the FDA and before giving any
material submission to the FDA, and (ii) prior to making any material change to
a study protocol, the addition of new trials, or a material change to the
development timeline for any of its product candidates or programs;

            (u) Authorize any single capital expenditure in excess of $200,000
or capital expenditure which in the aggregate exceed $500,000;

            (v) Make any loans, advances or capital contributions to, or
investments in, any other person (other than to wholly-owned subsidiaries of the
Company or customary advances to employees for travel and business expenses in
the ordinary course of business);

            (w) Settle or compromise any pending or threatened suit, action or
claim which is material or which relates to the transactions contemplated
hereby;

            (x) Effectuate a "plant closing" or "mass layoff," as those terms
are defined in the Worker Adjustment and Retraining Notification Act of 1988, or
effectuate any similar action under any foreign Law;

            (y) Modify, amend or terminate, or waive, release or assign any
material rights or claims with respect to any confidentiality agreement or
non-competition Agreement to which Company is a party;

            (z) Commence any litigation or arbitration other than in accordance
with past practice or settle any litigation or arbitration for money damages or
other relief in excess of $100,000, or if as part of such settlement the Company
or any of its subsidiaries would agree to any restrictions on its operations, or
which relates to this Agreement or the Transactions; or

                                       34


            (aa)  Enter into any written agreement, contract, commitment or
arrangement to do any of the foregoing, or authorize, recommend, propose or
agree, in writing or otherwise, or announce an intention to do any of the
foregoing.

     5.2    NO SOLICITATION.

            (a) Each of the Company and its Representatives (as defined below)
has ceased and caused to be terminated all existing solicitations, initiations,
encouragements, discussions, negotiations and communications with any persons or
entities with respect to any offer or proposal or potential offer or proposal
relating to any transaction or proposed transaction or series of related
transactions, other than the Transactions, involving: (A) any acquisition or
purchase from the Company by any person or "group" (as defined under Section
13(d) of the Exchange Act and the rules and regulations thereunder) of more than
a twenty percent (20%) interest in the total outstanding voting securities of
the Company or any of its Subsidiaries or any tender offer or exchange offer
that if consummated would result in any person or "group" (as defined under
Section 13(d) of the Exchange Act and the rules and regulations thereunder)
beneficially owning twenty percent (20%) or more of the total outstanding voting
securities of the Company or any of its Subsidiaries or any merger, (B) any
consolidation, business combination, merger or similar transaction involving the
Company; (C) any sale, lease (other than in the ordinary course of business),
exchange, transfer, license (other than in the ordinary course of business),
acquisition or disposition of assets of the Company or its Subsidiaries
(including for this purpose the outstanding equity securities of the Company's
Subsidiaries) for consideration equal to twenty percent (20%) or more of the
fair market value of all of the outstanding shares of Company Common Stock on
the date prior to the date hereof; or (D) any recapitalization, restructuring,
liquidation or dissolution of the Company (each of clauses (A)-(D), an
"ACQUISITION PROPOSAL"). Except as provided in Section 5.2(b) or (c), from the
date of this Agreement until the earlier of termination of this Agreement or the
Effective Time, the Company shall not and shall not authorize or permit its
officers, directors, employees, investment bankers, attorneys, accountants or
other agents or those of its subsidiaries (collectively, "REPRESENTATIVES") to
directly or indirectly (i) initiate, solicit or knowingly encourage, or
knowingly take any action to facilitate the making of, any offer or proposal
which constitutes or is reasonably likely to lead to any Acquisition Proposal,
(ii) enter into any agreement with respect to any Acquisition Proposal, or (iii)
engage in negotiations or discussions with, or provide any information or data
to, any person (other than Parent or any of its affiliates or representatives)
relating to any Acquisition Proposal or grant any waiver or release under any
standstill or other agreement. Notwithstanding the foregoing, nothing contained
in this Section 5.2 or any other provision hereof shall prohibit the Company or
the Company Board of Directors from (x) taking and disclosing to the Company's
stockholders its position with respect to any tender or exchange offer by a
third party pursuant to Rules 14d-9 and 14e-2 promulgated under the Exchange
Act, or (y) making such disclosure to the Company's stockholders as in the good
faith judgment of the Company Board of Directors, after receipt of advice from
outside legal counsel, is required under applicable law and that the failure to
make such disclosure is reasonably likely to cause the Company Board of
Directors to violate its fiduciary duties to the Company's stockholders under
applicable law.

            (b) Notwithstanding the foregoing, prior to the acceptance of Shares
pursuant to the Offer, the Company may furnish information concerning its
business, properties or assets to

                                       35


any person pursuant to a confidentiality agreement with terms no less favorable
to the Company than those contained in the confidentiality agreement, dated June
12, 2003 entered into between Parent and the Company (as amended by Section
9.5(b) of this Agreement, the "CONFIDENTIALITY AGREEMENT"), and may negotiate
and participate in discussions and negotiations with such person concerning an
Acquisition Proposal if, but only if, (x) such Acquisition Proposal provides for
consideration to be received by the holders of all, but not less than all, of
the issued and outstanding Shares (a "TAKEOVER PROPOSAL"); (y) such person has,
in the absence of any violation of this Section 5.2 by the Company, submitted a
bona fide written proposal to the Company relating to any such Takeover Proposal
which the Board of Directors determines in good faith involves consideration to
the holders of the Shares that is superior to the consideration offered pursuant
to the Offer, otherwise represents a superior transaction to the Offer and the
Merger, is reasonably capable of being consummated by the Termination Date (as
defined in Section 8.1(b)) and which is not conditioned upon obtaining
additional financing, or any regulatory approvals beyond or in addition to those
regulatory approvals specifically referenced in Section 7.1(d), and (z) in the
good faith opinion of the Company Board of Directors, after receipt of advice
from outside legal counsel, providing such information or access or engaging in
such discussions or negotiations is in the best interests of the Company and its
stockholders and the failure to provide such information or access or to engage
in such discussions or negotiations is reasonably likely to cause the Company
Board of Directors to violate its fiduciary duties to the Company's stockholders
(a Takeover Proposal which satisfies clauses (x), (y) and (z) being referred to
herein as a "SUPERIOR PROPOSAL"). The Company shall promptly (and in any case
within 24 hours) notify Parent (i) of such Superior Proposal, which notice shall
include a copy of such Superior Proposal and (ii) upon receipt of any inquiries,
proposals or offers received by, any request for information from, or any
discussions or negotiations sought to be initiated or continued with, either the
Company, or of its Subsidiaries or Representatives concerning an Acquisition
Proposal or that would reasonably be expected to lead to an Acquisition Proposal
and disclose the identity of the other party and the material terms of such
inquiry, offer, proposal or request and, in the case of written materials,
provide copies of such materials. The Company will keep Parent informed on a
reasonably prompt basis (and, in any case, within 24 hours of any significant
development) of the status and details (including amendments and proposed
amendments) of any such Superior Proposal or other inquiry, offer, proposal or
request. The Company shall promptly, following a determination by the Company
Board of Directors that a Takeover Proposal is a Superior Proposal, notify
Parent of such determination.

            (c) Except as set forth herein, neither the Company Board of
Directors nor any committee thereof shall (i) withdraw or modify, or propose to
withdraw or modify, in a manner adverse to the Transactions contemplated by this
Agreement to Parent or Purchaser, the approval or recommendation by the Company
Board of Directors or any such committee of the Offer, this Agreement or the
Merger, (ii) approve or recommend or propose to approve or recommend, any
Acquisition Proposal or (iii) enter into any agreement with respect to any
Acquisition Proposal. Notwithstanding the foregoing, prior to the time of
acceptance for payment of Shares in the Offer, the Company Board of Directors
may (subject to the terms of this and the following two sentences) withdraw or
modify its approval or recommendation of the Offer, this Agreement or the
Merger, or recommend a Superior Proposal, in either case at any time after (x),
it has concluded in good faith, after receipt of advice from outside legal
counsel, that the failure to take such action is reasonably likely to result in
a breach of its fiduciary duties to the Company's stockholders and (y) the fifth
(5th) business day following the Company's delivery to Parent of

                                       36


written notice advising Parent that the Company Board of Directors has received
a Superior Proposal (which notice shall include a copy of such Superior
Proposal) and identify the Person making such Superior Proposal and advising
Parent that the Company intends to withdraw or modify its recommendation of the
Offer, this Agreement or the Merger or recommend a Superior Proposal (specifying
which course of action the Company intends to take) (a "SUBSEQUENT
DETERMINATION"). After providing such notice, the Company shall provide to
Parent two (2) business days from the date of such notice to make such
adjustments in the terms and conditions of this Agreement as would enable the
Company to proceed with its original recommendation to stockholders without
making a Subsequent Determination; provided, however, that any such adjustments
shall be at the discretion of the parties at such time. Any such withdrawal,
modification or change of the recommendation of the Company Board of Directors,
or recommendation or proposed recommendation of any Superior Proposal shall not
change the approval of the Company Board of Directors for purposes of causing
any state takeover statute or other state law to be inapplicable to the
Transactions contemplated by this Agreement, including each of the Offer and the
Merger.

                                   ARTICLE VI

                              ADDITIONAL AGREEMENTS

     6.1    PROXY STATEMENT. If required by the Exchange Act, the Company shall
prepare and file with the SEC, as promptly as practicable after the consummation
of the Offer, and shall use its reasonable efforts to respond promptly to any
comments made by the SEC, and promptly thereafter shall mail to stockholders,
the Proxy Statement. In such event, subject to the terms and conditions of this
Agreement, the Proxy Statement shall contain the recommendation of the Company
Board of Directors in favor of the Merger.

     6.2    MEETING OF STOCKHOLDERS OF THE COMPANY. In connection with the
Special Meeting, if any, the Company shall, subject to the terms and conditions
of this Agreement, use its reasonable efforts to solicit from stockholders of
the Company proxies in favor of the Merger, and shall take all other action
necessary or, in the reasonable opinion of Purchaser, advisable to secure any
vote or consent of such stockholders required by the DGCL and the Company's
Certificate of Incorporation to effect the Merger. Purchaser agrees that it
shall vote, or cause to be voted, in favor of the Merger all Shares directly or
indirectly beneficially owned by it.

     6.3    CONFIDENTIALITY; ACCESS TO INFORMATION.

            (a) The parties acknowledge that the Company and Parent have
previously executed the Confidentiality Agreement. Unless otherwise required by
law or regulation or pursuant to the terms and provisions of the Confidentiality
Agreement, Parent and the Purchaser will hold any information which is
non-public in confidence in accordance with the terms of the Confidentiality
Agreement and, in the event this Agreement is terminated for any reason, Parent
or the Purchaser shall promptly return or destroy such information in accordance
with the Confidentiality Agreement.

            (b) The Company will afford Parent and its Representatives
reasonable access during normal business hours to the properties, books,
analysis, projections, plans, systems,

                                       37


contracts, commitments, records, personnel offices and other facilities of the
Company and its subsidiaries during the period prior to the Effective Time to
obtain information concerning the business, including the status of product
development efforts, properties, results of operations and personnel of the
Company and use commercially reasonable efforts to make available at reasonable
times during normal business hours to Parent and its Representatives, the
appropriate individuals (including management personnel, attorneys, accountants
and other professionals) for discussion of the Company's business, properties,
prospects and personnel as Parent may reasonably request.

     6.4    PUBLIC DISCLOSURE. The initial press release concerning the Offer
and the Merger shall be a joint press release and, thereafter, so long as this
Agreement is in effect, neither Parent, Purchaser nor the Company will
disseminate any press release or other announcement concerning the Merger, the
Offer or this Agreement or the other Transactions contemplated by this Agreement
to any third party, except as may be required by law or by any listing agreement
with the Nasdaq National Market, without the prior consent of each of the other
parties hereto, which consent shall not be unreasonably withheld. The parties
have agreed to the text of the joint press release announcing the execution of
this Agreement. Notwithstanding the foregoing, without prior consent of the
other party, each party (a) may communicate information that is not confidential
to the other party with financial analysts, investors and media representatives
in a manner consistent with its past practice in compliance with applicable Law
and (b) may disseminate material substantially similar to material included in a
press release or other document previously approved for external distribution by
the other party. Each party agrees to promptly make available to the other party
copies of any written communications made without prior consultation with the
other party.

     6.5    REGULATORY FILINGS; REASONABLE EFFORTS.

            (a) As promptly as practicable after the date hereof, each of
Parent, Purchaser and the Company shall make all filings, notices, petitions,
statements, registrations, submissions of information, application or submission
of other documents required by any Governmental Entity in connection with the
Merger and the other Transactions, including, without limitation: (i)
Notification and Report Forms with the United States Federal Trade Commission
(the "FTC") and the Antitrust Division of the United States Department of
Justice ("DOJ") as required by the HSR Act, (ii) filings required by the merger
notification or control laws of any applicable jurisdiction, as agreed by the
parties hereto, and (iv) any filings required under the Securities Act, the
Exchange Act, any applicable state or securities or "blue sky" laws and the
securities laws of any foreign country, or any other applicable laws or rules
and regulations of any Governmental Entity relating to the Merger. Each of
Parent and the Company will cause all documents that it is responsible for
filing with any Governmental Entity under this Section 6.5(a) to comply in all
material respects with all applicable laws and rules and regulations of any
Governmental Entity.

            (b) Each of Parent, Purchaser, and the Company shall promptly supply
the other with any information which may be required in order to effectuate any
filings or application pursuant to Section 6.5(a). Except where prohibited by
applicable laws and rules and regulations of any Governmental Entity, and
subject to the Confidentiality Agreement, each of the Company and Parent shall
consult with the other prior to taking a position with respect to any such
filing,

                                       38


shall permit the other to review and discuss in advance, and consider in good
faith the views of the other in connection with any analyses, appearances,
presentations, memoranda, briefs, white papers, arguments, opinions and
proposals before making or submitting any of the foregoing to any Governmental
Entity by or on behalf of any party hereto in connection with any investigations
or proceedings in connection with this Agreement or the transactions
contemplated hereby (including under any antitrust or fair trade laws),
coordinate with the other in preparing and exchanging such information and
promptly provide the other (or its counsel) with copies of all filings,
presentations or submissions (and a summary of any oral presentations) made by
such party with any Governmental Entity in connection with this Agreement or the
transactions contemplated hereby, provided that with respect to any such filing,
presentation or submission, each of Parent and the Company need not supply the
other (or its counsel) with copies (or in case of oral presentations, a summary)
to the extent that any law, treaty, rule or regulation of any Governmental
Entity applicable to such party requires such party or its Subsidiaries to
restrict or prohibit access to any such properties or information.

            (c) Each of Parent, Purchaser and the Company will notify the others
promptly upon the receipt of: (i) any comments from any officials of any
Governmental Entity in connection with any filings made pursuant hereto and (ii)
any request by any officials of any Governmental Entity for amendments or
supplements to any filings made pursuant to, or information provided to comply
in all material respects with, any applicable laws and rules and regulations of
any Governmental Entity. Whenever any event occurs that is required to be set
forth in an amendment or supplement to any filing made pursuant to Section
6.5(a), Parent, Purchaser or the Company, as the case may be, will promptly
inform the others of such occurrence and cooperate in filing with the applicable
Governmental Entity such amendment or supplement.

            (d) Upon the terms and subject to the conditions set forth in this
Agreement, each of the parties agrees to use its reasonable efforts to take, or
cause to be taken, all actions, and to do, or cause to be done, and to assist
and cooperate with the other parties in doing, all things necessary, proper or
advisable to consummate and make effective, in the most expeditious manner
practicable, the Merger and the other Transactions, including complying in all
material respects with all applicable laws and with all rules and regulations of
any Governmental Entity and using its reasonable efforts to accomplish the
following: (i) the taking of its reasonable acts necessary to cause all the
conditions set forth in Article VII and in Annex I hereto to be satisfied and to
consummate and make effective the Merger and the other Transactions, (ii) the
obtaining of all necessary actions or nonactions, waivers, consents, clearances,
approvals, orders and authorizations from Governmental Entities and the making
of all necessary registrations, declarations and filings (including
registrations, declarations and filings with Governmental Entities, if any) and
the taking of all reasonable steps as may be necessary to avoid any suit, claim,
action, investigation or proceeding by any Governmental Entity, (iii) the
obtaining of all necessary consents, approvals or waivers from third parties,
(iv) the defending of any suits, claims, actions, investigations or proceedings,
whether judicial or administrative, challenging this Agreement or the
consummation of the Transactions, including seeking to have any stay or
temporary restraining order entered by any court or other Governmental Entity
vacated or reversed, and (v) the execution or delivery of any additional
instruments necessary to consummate the Transactions, and to carry out fully the
purposes of, this Agreement. In connection with and without limiting the
foregoing, the Company and its Board of Directors

                                       39


shall, if any state takeover statute or similar statute or regulation is or
becomes applicable to the Merger, this Agreement or any of the other
Transactions, use all reasonable efforts to ensure that the Merger and the other
Transactions may be consummated as promptly as practicable on the terms
contemplated by this Agreement and otherwise to minimize the effect of such
statute or regulation on the Merger, this Agreement and the other Transactions.
In case at any time after the Effective Time any further action is necessary or
desirable to carry out the purposes of this Agreement, the proper officers and
directors of the Company, Parent and Purchaser shall use all reasonable efforts
to take, or cause to be taken, all such necessary actions. Parent shall cause
Purchaser to fulfill all Purchaser's obligations under, and pursuant to, this
Agreement. Nothing in this Agreement shall require Parent, Purchaser or any
other subsidiary of Parent to sell, hold separate, license or otherwise dispose
of or conduct their business in a specified manner, or agree to sell, hold
separate, license or otherwise dispose of or conduct their business in a
specified manner, or permit the sale, holding separate, licensing or other
disposition of, any assets of Parent, Purchaser or any other subsidiary of
Parent, whether as a condition to obtaining any approval from a Governmental
Entity or any other person or for any other reason. Until this Agreement is
terminated in accordance with Section 8.1, Parent shall have the right to
participate in the defense of any action, suit or proceeding instituted against
the Company (or any of its directors or officers) before any court or
governmental or regulatory body or threatened by any governmental or regulatory
body, to restrain, modify or prevent the consummation of the Transactions, or to
seek damages or a discovery order in connection with such Transactions.

     6.6    NOTIFICATION OF CERTAIN MATTERS. Each party shall give prompt notice
to the other parties of (i) the occurrence or non-occurrence of any event the
occurrence or non-occurrence of which would cause any representation or warranty
made by such party in this Agreement to be untrue or inaccurate in any material
respect at any time from the date hereof to the Effective Time, (ii) any
condition set forth in Annex I that is unsatisfied in any material respect at
any time from the date hereof to the date the Purchaser purchases Shares
pursuant to the Offer (except to the extent it refers to a specific date), and
(iii) any material failure of such party or any of its representatives to comply
with or satisfy any covenant, condition or agreement to be complied with or
satisfied by it hereunder; provided, however, that no such notification shall
affect the representations, warranties, covenants or agreements of the parties,
the conditions to the obligations of the parties under this Agreement or the
remedies available to the party receiving such notification.

     6.7    INDEMNIFICATION.

            (a) Parent agrees that at all times after the Effective Time, it
shall indemnify, or shall cause the Surviving Corporation and its subsidiaries
to indemnify, each person who is now, or has been at any time prior to the date
hereof, a director or officer of the Company or of any of the Company's
subsidiaries, successors and assigns (individually an "INDEMNIFIED PARTY" and
collectively the "Indemnified Parties"), to the same extent and in the same
manner as is now provided in the respective Certificates of Incorporation or
Bylaws of the Company and such subsidiaries and any Indemnity Agreement
currently in effect, with respect to any claim, liability, loss, damage, cost or
expense (whenever asserted or claimed) ("INDEMNIFIED LIABILITY") based in whole
or in part on, or arising in whole or in part out of, any matter existing or
occurring at or prior to the Effective Time. Parent understands and agrees that,
prior to the Effective Time, the Company intends to obtain a six year "tail"
insurance policy that provides coverage substantially

                                       40


similar to the coverage provided under the Company's directors and officers
insurance policy in effect on the date of this Agreement for the individuals who
are directors and officers of the Company on the date of this Agreement for
events occurring prior to the Effective Time; provided, however, without
Parent's prior written consent (which consent shall not be unreasonably withheld
or delayed), the Company shall not pay more than $3,500,000 to purchase such
policy; provided, however, that prior to purchasing such policy, the Company
shall afford Parent the opportunity to purchase a substitute policy on terms not
materially less favorable to the Company and the Indemnified Parties.

            (b) This Section 6.7 is intended to be for the benefit of, and shall
be enforceable by, the Indemnified Parties and their heirs and personal
representatives and shall be binding on Parent and Surviving Corporation and its
successors and assigns. In the event the Company or the Surviving Corporation or
any of their respective successors or assigns (i) consolidates with or merges
into any other person and shall not be the continuing or surviving corporation
or entity in such consolidation or merger or (ii) transfers all or substantially
all of its properties and assets to any person, then, and in each case, proper
provision shall be made so that the successors and assigns of the Surviving
Corporation honor the indemnification obligations set forth in this Section 6.7.

            (c) The Company Board of Directors shall take all action necessary
to prevent Section 11(a) of any Indemnity Agreement from becoming applicable to
the Agreement or the Transactions and to determine that the creation of any
trust pursuant to Section 11(b) of any Indemnity Agreement would not be in the
best interests of the Company.

     6.8    EMPLOYEE BENEFITS.

            (a) Following the Merger, Parent shall cause the Surviving
Corporation to provide that the employees of the Surviving Corporation are
covered under Parent's then-current benefits plans, programs, policies and
arrangements applicable to similarly situated employees of Parent. Years of
service with the Company and its subsidiaries prior to the Effective Time shall
be treated as service with the Surviving Corporation or Parent for all
eligibility and vesting purposes and for purposes of vacation and severance pay
accruals, except to the extent such treatment will result in a duplication of
benefits.

            (b) Following the Merger, Parent shall take commercially reasonable
efforts to cause to be waived all limitations as to preexisting condition
limitations, exclusions and waiting periods with respect to participation and
coverage requirements applicable to the employees of the Company and its
subsidiaries under any medical or dental benefit plans that such employees are
eligible to participate in after the Effective Time, other than limitations,
exclusions or waiting periods that are already in effect with respect to such
employees and that have not been satisfied as of the Effective Time under any
medical or dental plan maintained for such employees immediately prior to the
Effective Time. If and only if requested by Parent, the Company shall terminate
its 401(k) plan and its Nonqualifed Deferred Compensation Plan at least one day
before the Closing Date.

     6.9    CONSENTS AND APPROVALS. Each of the Company, Parent and Purchaser
will take all reasonable actions necessary to (i) comply promptly with all legal
requirements which may be

                                       41


imposed on it with respect to this Agreement and the Transactions, (ii) promptly
cooperate with and furnish information to each other in connection with any such
requirements imposed upon any of them or any of their subsidiaries in connection
with this Agreement and the Transactions contemplated hereby and thereby and
(iii) take and cause its respective subsidiaries to, take all reasonable actions
necessary to obtain any consent, authorization, order or approval of, or any
exemption by, any Governmental Entity or other public or private third party
required to be obtained or made by Parent, Purchaser the Company or any of their
subsidiaries in connection with the Offer or the Merger or the taking of any
action contemplated thereby or by this Agreement (collectively, the "REQUISITE
REGULATORY APPROVALS").

     6.10   ADDITIONAL AGREEMENTS. Subject to the terms and conditions herein
provided, each of the parties hereto agrees to use all reasonable efforts to
take, or cause to be taken, all action and to do, or cause to be done, all
things necessary, proper or advisable, whether under applicable laws and
regulations or otherwise, or to remove any injunctions or other impediments or
delays, legal or otherwise, to satisfy the conditions to the Offer and make
effective the Merger and the other transactions contemplated by this Agreement.
In case at any time after the Effective Time any further action is necessary or
desirable to carry out the purposes of this Agreement, the proper officers and
directors of the Company and Parent shall use all reasonable efforts to take, or
cause to be taken, all such necessary actions.

     6.11   DIRECTORS.

            (a) Promptly upon the first acceptance for payment of, and payment
by Purchaser for, any Shares which represent at least a majority of Fully
Diluted Shares pursuant to the Offer, Parent shall be entitled to designate such
number of directors on the Company Board of Directors as will give Parent,
subject to compliance with Section 14(f) of the Exchange Act, representation on
the Company Board of Directors equal to at least that number of directors,
rounded up to the next whole number, which is the product of (x) the total
number of directors on the Company Board of Directors (giving effect to the
directors elected pursuant to this sentence) multiplied by (y) the percentage
that (I) such number of Shares so accepted for payment and paid for by Purchaser
plus the number of Shares otherwise owned by Parent, Purchaser or any other
subsidiary of Parent bears to (II) the number of such Shares outstanding, and
the Company shall, at such time, cause Parent's designees to be so elected;
provided, however, that in the event that Parent's designees are appointed or
elected to the Company Board of Directors, until the Effective Time the Company
Board of Directors shall have at least three directors who are directors on the
date of this Agreement and who are not officers of the Company (the "INDEPENDENT
DIRECTORS"); and provided further that, in such event, if the number of
Independent Directors shall be reduced below three for any reason whatsoever,
any remaining Independent Directors (or Independent Director, if there shall be
only one remaining) shall be entitled to designate persons to fill such
vacancies who shall be deemed to be Independent Directors for purposes of this
Agreement or, if no Independent Directors then remain, the other directors shall
designate three persons to fill such vacancies who are not officers or
affiliates of the Company, Parent or Purchaser, and such persons shall be deemed
to be Independent Directors for purposes of this Agreement. At such time, the
Company shall, upon Parent's request, also cause persons elected or designated
by Parent to constitute the same percentage (rounded up to the next whole
number) as is on the Company Board of Directors of (i) each committee of the
Company Board of Directors of Directors, (ii) each board of directors (or

                                       42


similar body) of each of the Company's Subsidiaries, and (iii) each committee
(or similar body) of each such board, in each case only to the extent permitted
by applicable law or the rules of any stock exchange on which the Company Common
Stock is listed. Subject to applicable Law, the Company shall take all action
requested by Parent necessary to effect any such election, including mailing to
its stockholders the Information Statement containing the information required
by Section 14(f) of the Exchange Act and Rule 14f-1 promulgated thereunder, and
the Company shall make such mailing with the mailing of the Schedule 14D-9
(provided that Purchaser shall have provided to the Company on a timely basis
all information required to be included in the Information Statement with
respect to Purchaser's designees). In connection with the foregoing, the Company
shall promptly, at the option of Purchaser, either increase the size of the
Company Board of Directors or obtain the resignation of such number of its
current directors, or both, as is necessary to enable Purchaser's designees to
be elected or appointed to the Company Board of Directors as provided above.

            (b) Notwithstanding anything in this Agreement to the contrary, if
Parent's designees constitute a majority of the Company Board of Directors after
the acceptance for payment of Shares pursuant to the Offer and prior to the
Effective Time, then the affirmative vote of a majority of the Independent
Directors (or if only one exists, then the vote of such Independent Director)
shall be required to (i) amend or terminate this Agreement by the Company, (ii)
exercise or waive any of the Company's rights, benefits or remedies hereunder,
if such action would materially and adversely affect holders of Shares other
than Parent or Purchaser, (iii) amend the Certificate of Incorporation or Bylaws
of the Company, or (iv) take any other action of the Company Board of Directors
under or in connection with this Agreement or the Transaction; provided,
however, that if there shall be no Independent Directors as a result of such
persons' deaths, disabilities or refusal to serve, then such actions may be
effected by majority vote of the entire Company Board of Directors.

                                   ARTICLE VII

                                   CONDITIONS

     7.1    CONDITIONS TO OBLIGATIONS OF EACH PARTY TO EFFECT THE MERGER. The
respective obligations of each party to this Agreement to effect the Merger
shall be subject to the satisfaction or written waiver at or prior to the
Closing Date of the following conditions:

            (a) Stockholder Approval. The Merger and this Agreement shall have
been approved and adopted by the requisite vote of the holders of the Shares, to
the extent required pursuant to the requirements of the Certificate of
Incorporation and the DGCL.

            (b) Statutes; Court Orders. No statute, rule, executive order or
regulation shall have been enacted, issued, enforced or promulgated by any
Governmental Entity which prohibits the consummation of the Merger, and there
shall be no order or injunction of a court of competent jurisdiction in effect
preventing consummation of the Merger.

            (c) Purchase of Shares in Offer. Purchaser shall have purchased, or
caused to be purchased, all Shares properly tendered pursuant to the Offer;
provided, however, that this condition shall be deemed to have been satisfied
with respect to the obligation of Parent and

                                       43


Purchaser to effect the Merger even if Purchaser fails to accept for payment or
pay for Shares validly tendered pursuant to the Offer in violation of the terms
of the Offer or of this Agreement.

            (d) HSR. The applicable waiting period under the HSR Act and any
comparable provisions under any applicable pre-merger notification laws or
regulations of foreign jurisdictions shall have expired or been terminated.

            (e) Dissenting Shares. Fewer than ten percent (10%) of the
outstanding shares of Company Common Stock shall be Dissenting Shares.

     7.2    ADDITIONAL CONDITION TO THE OBLIGATIONS OF PARENT AND PURCHASER. The
obligations of Parent and Purchaser to consummate and effect the Merger shall be
subject to the additional condition, which may be waived in whole or in part by
Parent or Purchaser to the extent permitted by applicable law, that all actions
contemplated by Section 2.4 and 2.5(b) shall have been taken.

                                  ARTICLE VIII

                        TERMINATION, AMENDMENT AND WAIVER

     8.1    TERMINATION. This Agreement may be terminated and the Transactions
may be abandoned at any time before the Effective Time, whether before or after
stockholder approval thereof:

            (a) By mutual written consent of Parent and the Company duly
authorized by the Board of Directors of Parent (the "PARENT BOARD") and the
Company Board of Directors; or

            (b) By either Parent or the Company: (i) if a court of competent
jurisdiction or other Governmental Entity shall have issued an order, decree or
ruling or taken any other action, or there shall exist any statute, rule or
regulation, in each case permanently restraining, enjoining or otherwise
prohibiting (collectively, ("RESTRAINTS") the consummation of any of the
Transactions contemplated by this Agreement or if any Governmental Entity that
must grant a Requisite Regulatory Approval has denied approval of the Mergers;
provided, however, that the party seeking to terminate this Agreement pursuant
to this Section 8.1(b)(i) shall have used all reasonable efforts to prevent the
entry of and to remove such Restraint or to obtain such Requisite Regulatory
Approval, as the case may be; or (ii) if the Merger has not been consummated by
January 31, 2004 (the "TERMINATION DATE") at any time following the Termination
Date unless such party has expressly restricted in writing its right to
terminate this Agreement pursuant to this Section 8.1(b)(ii); provided, however,
that the right to terminate this Agreement pursuant to this Section 8.1(b)(ii)
shall not be available to any party whose action or failure to fulfill any
obligation under this Agreement has been the principal cause of, or resulted in,
the failure of the Merger to be consummated by such date; or

            (c) By Parent if (i) prior to the purchase of Shares pursuant to the
Offer, there has been a material breach by the Company of any representation,
warranty, covenant or agreement set forth in this Agreement, which breach has
resulted or is reasonably likely to result in any condition set forth in Annex I
not being satisfied (and such breach has not been cured or such condition has
not been satisfied within twenty (20) days after the receipt of notice thereof
or such

                                       44


breach is not reasonably capable of being cured or such condition is not
reasonably capable of being satisfied within such period); or (ii) due to an
occurrence or circumstance that has resulted or would result in a failure to
satisfy any condition set forth in Annex I hereto, Purchaser shall have (x)
failed to commence the Offer within ten (10) business days following the date of
this Agreement, (y) terminated the Offer, or allowed the offer to terminate,
without having accepted any Shares for payment thereunder or (z) failed to
accept Shares for payment pursuant to the Offer prior to the Termination Date,
unless such action or inaction under clauses (x), (y) or (z) shall have been
caused by or resulted from the failure of Parent or Purchaser to perform, in any
material respect, any of their covenants or agreements contained in this
Agreement, or the material breach by Parent or Purchaser of any of their
representations or warranties contained in this Agreement; or

            (d) By the Company if (i) prior to the purchase of Shares pursuant
to the Offer that would represent a majority of the Fully Diluted Shares, there
has been a material breach by Parent of any representation, warranty, covenant
or agreement set forth in this Agreement (and such breach has not been cured or
such condition has not been satisfied within thirty (30) days after the receipt
of notice thereof or such breach is not reasonably capable of being cured or
such condition is not reasonably capable of being satisfied within such period);
or (ii) other than due to an occurrence or circumstance that has resulted or
would result in a failure to satisfy any condition set forth in Annex I hereto,
Purchaser shall have (x) failed to commence the Offer within ten (10) business
days following the date of this Agreement, (y) terminated the Offer without
having accepted all Shares properly tendered for payment thereunder or (z)
failed to accept any Shares properly tendered for payment pursuant to the Offer
prior to the Termination Date, unless such action or inaction under clauses (x),
(y) or (z) shall have been caused by or resulted from the failure of the Company
to perform, in any material respect, any of its covenants or agreements
contained in this Agreement, or the material breach by the Company of any of its
representations or warranties contained in this Agreement; or

            (e) By Parent, at any time prior to the purchase of the Shares
pursuant to the Offer, if (i) the Company Board of Directors shall have, in a
manner adverse to the Parent, (v) withdrawn, modified or changed its approval or
recommendation of this Agreement or the Offer, or publicly announced its
intention to do so or failed to recommend this Agreement or the Offer, (w)
recommended to the Company's stockholders any proposal other than by Parent or
Purchaser in respect of an Acquisition Proposal, or publicly announced its
intention to do so, (x) made a Subsequent Determination, (y) adopted resolutions
approving or otherwise authorizing or recommending an Acquisition Proposal that
remain in effect and have not been rescinded, or (z) failed to recommend
against, or taken a neutral position with respect to, a tender or exchange offer
related to an Acquisition Proposal in any position taken pursuant to Rules 14d-9
and 14e-2 under the Exchange Act or (iii) the Company shall have materially
violated or breached any of its obligations under Section 5.2 and such violation
or breach has not been cured; or

            (f) By the Company, if the Company has received a Superior Proposal
and Parent has not terminated this Agreement by September 15, 2003; provided
that the Company has not materially breached Section 5.2 hereof; or

                                       45


            (g) By either Parent or the Company, if upon a vote at a duly held
meeting to obtain the Company Stockholder Approval, the Company Stockholder
Approval is not obtained; provided, however, that Parent may not terminate this
Agreement under this Section 8.1(g) if the Company Common Stock owned by Parent,
Purchaser or any of Parent's Subsidiaries shall not have been voted in favor or
obtaining the Company Stockholder Approval.

     8.2    EFFECT OF TERMINATION

            (a) Any termination of this Agreement under Section 8.1 hereof will
be effective immediately upon the delivery of a valid written notice of the
terminating party to the other party hereto and, if then due, payment of the
Termination Fee. In the event of termination of this Agreement as provided in
Section 8.1 hereof, this Agreement shall forthwith become null and void and be
of no further force or effect and there shall be no liability on the part of
Parent, Purchaser or the Company (or any of their respective directors,
officers, employees, stockholders, agents or representatives), except as set
forth in Section 6.3(a), Article VIII and Article IX, each of which shall remain
in full force and effect and survive any termination of this Agreement;
provided, however, that nothing herein shall relieve any party from liability
for fraud or the intentional and willful breach of any of its representations,
warranties, covenants or agreements set forth in this Agreement. No termination
of this Agreement shall affect the obligations of the parties contained in the
Confidentiality Agreement, all of which obligations shall survive termination of
this Agreement.

            (b) If Parent shall have terminated this Agreement pursuant to
Section 8.1(e), the Company shall promptly pay Parent a termination fee (the
"TERMINATION FEE") of $22,000,000. If the Company intends to terminate this
Agreement pursuant to Section 8.1(f), it shall, prior to and as a condition to
such termination, pay Parent the Termination Fee. If at any time when an
Alternative Proposal has been publicly announced or otherwise communicated to
the Company's Board of Directors and not withdrawn prior to the date of
termination, Parent shall have terminated this Agreement pursuant to (I) Section
8.1(b)(ii) or Section 8.1(c)(i) or (II) Section 8.1(c)(ii) as a result of the
failure to satisfy conditions (c) or (g) of Appendix A, and, in each case prior
to the first anniversary of this Agreement, the Company enters into a written
agreement, arrangement or understanding with respect to an Acquisition Proposal
with any party other than Parent or its affiliates and consummates a transaction
pursuant to such Acquisition Proposal, then the Company shall pay to Parent
promptly, but in no event later than ten (10) business days after the
consummation of such transaction, the Termination Fee. All amounts due hereunder
shall be payable by wire transfer in immediately available funds to such account
as Parent may designate in writing to the Company. In the event this Agreement
is properly terminated in accordance with its terms by either the Company or
Parent in a manner that requires the Company to pay Parent a Termination Fee,
and Parent has received the Termination Fee, neither Parent nor Purchaser shall
assert or pursue in any manner, directly or indirectly, (i) any claim or cause
of action based in whole or in part upon alleged tortious or other interference
with its rights under this Agreement against any entity or person submitting an
Acquisition Proposal, (ii) any claim or cause of action against the Company, its
affiliates or any of their respective officers, directors, employees,
stockholders, agents or representatives based in whole or in part upon a breach
of any representation, warranty or covenant in this Agreement, or (iii) any
claim or cause of action against the Company, its affiliates or any of their
respective officers, directors, employees, stockholders, agents or
representatives based in whole or in part upon its or their receipt,

                                       46


consideration, recommendation or approval of an Acquisition Proposal for the
Company's exercise of its right of termination; provided, however, that the
foregoing shall not relieve any party from liability for fraud or the
intentional and willful breach of this Agreement. If the Company fails to
promptly make any payment required under this Section 8.2(b) and Parent
commences a suit to collect such payment, the Company shall indemnify Parent for
its fees and expenses (including attorneys fees and expenses) incurred in
connection with such suit and shall pay interest on the amount of the payment at
the prime rate of Fleet National Bank (or its successors or assigns) in effect
on the date the payment was payable pursuant to this Section 8.2(b).

     8.3    FEES AND EXPENSES. Except as set forth in Section 8.2, all fees,
costs and expenses incurred in connection with this Agreement and the
Transactions shall be paid by the party incurring such expenses whether or not
the Merger is consummated; provided, however, that Parent and the Company shall
share equally all fees and expenses, other than attorneys' and accountants fees
and expenses, incurred in relation to the printing and filing with the SEC and
mailing of the Offer Documents, 14D-9 and Proxy Statement (including any
preliminary materials related thereto) and any amendments or supplements
thereto, and the filing of any documents required under the HSR Act or any
comparable provisions under any applicable pre-merger notification laws or
regulations of foreign jurisdictions.

     8.4    EXTENSION; WAIVER. At any time prior to the Effective Time any party
hereto may, to the extent legally allowed, (i) extend the time for the
performance of any of the obligations or other acts of the other parties hereto,
(ii) waive any inaccuracies in the representations and warranties made to such
party contained herein or in any document delivered pursuant hereto, and (iii)
waive compliance with any of the agreements or conditions for the benefit of
such party contained herein. Any agreement on the part of a party hereto to any
such extension or waiver shall be valid only if set forth in an instrument in
writing signed on behalf of such party. Delay in exercising any right under this
Agreement shall not constitute a waiver of such right.

                                   ARTICLE IX

                               GENERAL PROVISIONS

     9.1    NON-SURVIVAL OF REPRESENTATIONS AND WARRANTIES. None of the
representations and warranties in this Agreement or in any schedule, instrument
or other document delivered pursuant to this Agreement shall survive the
Effective Time and only the covenants that by their terms survive the Effective
Time and this Article IX shall survive the Effective Time.

     9.2    NOTICES. All notices and other communications hereunder shall be in
writing and shall be deemed given if delivered personally or by commercial
delivery service, or sent via telecopy (receipt confirmed) to the parties at the
following addresses or telecopy numbers (or at such other address or telecopy
numbers for a party as shall be specified by like notice):

                                       47


                  (a)   if to Parent or Purchaser:

                        Genzyme Corporation
                        One Kendall Square
                        Cambridge, MA 02139
                        Attention:  Executive Vice President, Theraputics
                        Telephone:  (617) 252-7500
                        Facsimile:  (617) 252-7553

                        with copies at the same address to the attention of the
                        General Counsel and the Clerk and with a copy to:

                        Ropes & Gray LLP
                        One International Place
                        Boston, MA 02110
                        Attention:  Paul M. Kinsella
                        Telephone:  (617) 951-7000
                        Facsimile:  (617) 951-7050


                  (b)   if to the Company:

                        SangStat Medical Corporation
                        6300 Dumbarton Circle
                        Fremont, CA 94555
                        Attention:  Chief Executive Officer
                        Telephone:  (510) 789-4300
                        Facsimile:  (510) 789-4424

                        with a copy at the same address to Adrian
                        Arima, General Counsel, and with a copy to:

                        Skadden, Arps, Slate, Meagher & Flom LLP
                        525 University Avenue, Suite 1100
                        Palo Alto, CA 94301
                        Attention:  Gregory C. Smith
                        Telephone:  (650) 470-4500
                        Facsimile:  (650) 470-4570

     9.3    INTERPRETATION; CERTAIN DEFINED TERMS.

            (a) When a reference is made in this Agreement to Exhibits, such
reference shall be to an Exhibit to this Agreement unless otherwise indicated.
When a reference is made in this Agreement to Sections, such reference shall be
to a Section of this Agreement unless otherwise indicated. The words "include,"
"includes" and "including" when used herein shall be deemed in each case to be
followed by the words "without limitation." The table of contents and headings

                                       48


contained in this Agreement are for reference purposes only and shall not affect
in any way the meaning or interpretation of this Agreement. When reference is
made herein to the "BUSINESS OF" an entity, such reference shall be deemed to
include the business of all direct and indirect subsidiaries of such entity.

            (b) For purposes of this Agreement, "AFFILIATES" shall have the
meaning set forth in Rule 12b-2 of the Exchange Act.

            (c) For purposes of this Agreement, any reference to a "MATERIAL
ADVERSE EFFECT" with respect to any entity or group of entities means any event,
change, condition or effect, event occurrence, states of facts or developments
(any such item, an "EFFECT"), individually or together with other events,
changes, conditions, effects, events, occurrences or states of facts or
developments, that (x) is materially adverse, in the short term or the long
term, to the condition (financial or otherwise), properties, assets (including
intangible assets), liabilities, business, operations or results of operations
of such entity and its subsidiaries, taken as a whole, or (y) would prevent or
materially alter or delay any of the Transactions; provided, however, that in no
event shall any of the following be taken into account in determining whether
there has been or will be a Material Adverse Effect on any entity: (A) any
Effect (other than litigation challenging the acquisition by Parent or Purchaser
of any Shares under the Offer, seeking to delay, restrain or prohibit the making
or consummation of the Offer or the Merger or the performance of any of the
other Transactions or seeking to obtain from the Company, Parent or Purchaser
any damages that are material in relation to the Company and the Company's
Subsidiaries taken as a whole) primarily resulting from compliance with the
terms and conditions of this Agreement; provided, that no inference may be drawn
hereby by any such litigation, (B) any Effect primarily resulting from the
announcement or pendency of the Transactions, (C) any change in such entity's
stock price or trading volume, (D) any Effect that results from changes
affecting the industry in which such entity operates generally or the United
States economy generally, without a disproportionate impact on such entity, (E)
any Effect that results from changes affecting general worldwide economic or
capital market conditions, without a disproportionate impact on such entity, or
(F) after September 30, 2003, any failure by such entity to meet published
revenue or earnings projections or any internal projections for any period
ending (or for which earnings are released) on or after the date of this
Agreement and prior to the Closing Date, provided that no inference may be drawn
hereby by any failure to meet a projection prior to September 30, 2003.

            (d) For purposes of this Agreement, the term "PERSON" shall mean any
individual, corporation (including any non-profit corporation), general
partnership, limited partnership, limited liability partnership, joint venture,
estate, trust, company (including any limited liability company or joint stock
company), firm or other enterprise, association, organization, entity or
Governmental Entity.

            (e) For purposes of this Agreement, a "SUBSIDIARY" of a specified
entity shall mean a "significant subsidiary" of such entity as the term
"significant subsidiary" is defined in Rule 1-02(w) of Regulation S-X under the
Securities Act.

            (f) For purposes of this Agreement, "TRANSACTIONS" shall mean all of
the transactions contemplated in this Agreement, including the Offer and the
Merger.

                                       49


            (g) For purposes of this Agreement, the term "KNOWLEDGE" means, with
respect to the Company, with respect to any matter in question, that any of
Richard D. Murdock, Stephen G. Dance, Raymond J. Tesi, Raysam S. Prasad, Steve
Aselage, Ralph Levy and Adrian Arima has actual knowledge of such matter. For
the purposes of the first sentence of Section 3.13(h) of this Agreement, the
term "Knowledge" means, with respect to the Company, with respect to any matter
in question that any of Richard D. Murdock, Stephen G. Dance, Raymond J. Tesi,
Raysam S. Prasad, Steve Aselage, Ralph Levy, Adrian Arima and Marlene Perry has
actual knowledge of such matter.

     9.4    COUNTERPARTS. This Agreement may be executed in two or more
counterparts, and by facsimile, all of which shall be considered one and the
same agreement and shall become effective when one or more counterparts have
been signed by each of the parties and delivered to the other party, it being
understood that all parties need not sign the same counterpart.

     9.5    ENTIRE AGREEMENT; THIRD PARTY BENEFICIARIES.

            (a) This Agreement and the documents and instruments and other
agreements among the parties hereto as contemplated by or referred to herein,
including the Company Disclosure Letter (a) constitute the entire agreement
among the parties with respect to the subject matter hereof and supersede all
prior agreements and understandings, both written and oral, among the parties
with respect to the subject matter hereof, it being understood that the
provisions of this Agreement shall supersede any conflicting provisions of the
Confidentiality Agreement, as amended by Section 9.5(b) hereof; and (b) are not
intended to confer upon any other person any rights or remedies hereunder,
except as specifically provided in Section 6.7.

            (b) By the execution of this Agreement, the Confidentiality
Agreement shall be deemed to be amended to include the following sentence at the
end of Section 3 thereof: "Notwithstanding anything to the contrary contained in
this Agreement, each party and its Representatives may disclose to any and all
persons, without limitation of any kind, the U.S. tax treatment and U.S. tax
structure of the business combination contemplated hereby and all materials of
any kind (including opinions or other tax analyses) that are provided to each
party or its Representatives relating to such tax treatment and tax structure."

     9.6    SEVERABILITY. In the event that any provision of this Agreement or
the application thereof, becomes or is declared by a court of competent
jurisdiction or other authority to be invalid, illegal, void, unenforceable or
against its regulatory policy, the remainder of this Agreement will continue in
full force and effect and the application of such provision to other persons or
circumstances will be interpreted so as reasonably to effect the intent of the
parties hereto. The parties further agree to replace such void or unenforceable
provision of this Agreement with a valid and enforceable provision that will
achieve, to the extent possible, the economic, business and other purposes of
such void or unenforceable provision.

     9.7    OTHER REMEDIES; SPECIFIC PERFORMANCE. Except as otherwise provided
herein, any and all remedies herein expressly conferred upon a party will be
deemed cumulative with and not exclusive of any other remedy conferred hereby,
or by law or equity upon such party, and the exercise by a party of any one
remedy will not preclude the exercise of any other remedy. The parties hereto
agree that irreparable damage would occur in the event that any of the
provisions

                                       50


of this Agreement were not performed in accordance with their specific terms or
were otherwise breached. It is accordingly agreed that the parties shall be
entitled to seek an injunction or injunctions to prevent breaches of this
Agreement and to enforce specifically the terms and provisions hereof in any
court of the United States or any state having jurisdiction, this being in
addition to any other remedy to which they are entitled at law or in equity. In
the event that any action shall be brought in equity to enforce the provisions
of the Agreement, neither party will allege, and each party hereby waives the
defense, that there is an adequate remedy at law.

     9.8    GOVERNING LAW; VENUE. This Agreement and all actions arising under
or in connection therewith shall be governed by and construed in accordance with
the laws of the State of Delaware, regardless of the laws that might otherwise
govern under applicable principles of conflicts of law thereof, provided,
however, that the laws of the respective jurisdictions of incorporation of each
of the parties shall govern the relative rights, obligations, powers, duties and
other internal affairs of such party and its board of directors. Each of the
parties hereto (a) consents to submit itself to the personal jurisdiction of any
federal court located in the State of Delaware or any Delaware state court in
the event any dispute arises out of this Agreement or any of the Transactions,
(b) agrees that it shall not attempt to deny or defeat such personal
jurisdiction by motion or other request for leave from any such court and (c)
agrees that it shall not bring any action relating to this Agreement or any of
the Transactions in any court other than a federal or state court sitting in the
State of Delaware.

     9.9    RULES OF CONSTRUCTION. The parties hereto agree that they have been
represented by counsel during the negotiation and execution of this Agreement
and, therefore, waive the application of any law, regulation, holding or rule of
construction providing that ambiguities in an agreement or other document will
be construed against the party drafting such agreement or document.

     9.10   ASSIGNMENT. This Agreement shall not be assigned by any of the
parties hereto (whether by operation of law or otherwise) without the prior
written consent of the other parties, except that the Purchaser may assign, in
its sole discretion and without the consent of any other party, any or all of
its rights, interests and obligations hereunder to (i) Parent, (ii) to Parent
and one or more direct or indirect wholly-owned subsidiaries of Parent, or (iii)
to one or more direct or indirect wholly-owned subsidiaries of Parent (each, an
"ASSIGNEE"). Any such Assignee may thereafter assign, in its sole discretion and
without the consent of any other party, any or all of its rights, interests and
obligations hereunder to one or more additional Assignees. Subject to the
preceding sentence, but without relieving any party hereto of any obligation
hereunder, this Agreement will be binding upon, inure to the benefit of and be
enforceable by the parties and their respective successors and assigns.

     9.11   AMENDMENT AND MODIFICATION. Subject to applicable law and as
otherwise provided in the Agreement, this Agreement may be amended, modified and
supplemented in any and all respects, whether before or after any vote of the
stockholders of the Company contemplated hereby, by written agreement of the
parties hereto, by action taken by their respective Boards of Directors or
equivalent governing bodies, but, after the purchase of Shares pursuant to the
Offer, no amendment shall be made which decreases the Merger Consideration and,
after the approval of this Agreement by the stockholders, no amendment shall be
made which by law requires further approval by such stockholders without
obtaining such further

                                       51


approval. This Agreement may not be amended except by an instrument in writing
signed on behalf of each of the parties hereto.

     9.12   NO WAIVER; REMEDIES CUMULATIVE. No failure or delay on the part of
any party hereto in the exercise of any right hereunder will impair such right
or be construed to be a waiver of, or acquiescence in, any breach of any
representation, warranty or agreement herein, nor will any single or partial
exercise of any such right preclude other or further exercise thereof or of any
other right. All rights and remedies existing under this Agreement are
cumulative to, and not exclusive to, and not exclusive of, any rights or
remedies otherwise available.

     9.13   CONTROL OF COMPANY'S BUSINESS. Nothing contained in this Agreement
shall give Parent, directly or indirectly, the right to control or direct the
Company's operations prior to the consummation of the Offer. Prior to the
consummation of the Offer, the Company shall exercise, consistent with the terms
and conditions of this Agreement, complete control and supervision over its
operations.

     9.14   WAIVER OF JURY TRIAL. EACH OF PARENT, THE COMPANY AND PURCHASER
HEREBY IRREVOCABLY WAIVES AND COVENANTS THAT THEY WILL NOT ASSERT THE RIGHT TO A
TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED IN
CONTRACT, TORT OR OTHERWISE) ARISING OUT OF, UNDER OR IN CONNECTION WITH THIS
AGREEMENT, OR ANY COURSE OF CONDUCT, COURSE OF DEALINGS, STATEMENT OR ACTION
RELATED HERETO OR THERETO.

                                      *****

                                       52


            IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be executed by their duly authorized respective officers as of the date first
written above.

                                         GENZYME CORPORATION

                                         By:
                                                --------------------------------
                                         Name:
                                                --------------------------------
                                         Title:
                                                --------------------------------


                                         SWIFT STARBOARD CORPORATION

                                         By:
                                                --------------------------------
                                         Name:
                                                --------------------------------
                                         Title:
                                                --------------------------------


                                         SANGSTAT MEDICAL CORPORATION

                                         By:
                                                --------------------------------
                                         Name:
                                                --------------------------------
                                         Title:
                                                --------------------------------

                                       53


                                     ANNEX I

     Notwithstanding any other provisions of the Offer, and in addition to (and
not in limitation of) Purchaser's rights to extend and amend the Offer at any
time in its sole discretion (subject to the provisions of the Merger Agreement),
Purchaser shall not be required to accept for payment or, subject to any
applicable rules and regulations of the SEC, including Rule 14e-l(c) under the
Exchange Act (relating to Purchaser's obligation to pay for or return tendered
Shares promptly after termination or withdrawal of the Offer), pay for, and may
delay the acceptance for payment of or, subject to the restriction referred to
above, the payment for, any validly tendered Shares if, there shall not have
been validly tendered and not withdrawn prior to the expiration of the Offer
that number of Shares which, together with that number of Shares owned by
Parent, Purchaser and Parent's other subsidiaries, would represent a majority of
the Fully Diluted Shares (the "MINIMUM TENDER CONDITION"). The term "FULLY
DILUTED SHARES" means all outstanding securities entitled generally to vote in
the election of directors of the Company on a fully diluted basis, assuming the
exercise or conversion of all vested options, rights and securities exercisable
or convertible into such voting securities. Furthermore, notwithstanding any
other provisions of the Offer, the Purchaser shall not be required to accept for
payment or pay for any validly tendered shares if, at the Expiration Date (i)
any applicable waiting periods under the HSR Act have not expired or terminated
prior to the termination of the Offer; (ii) and any clearances, permits,
authorizations, consents or approvals as may be required under any applicable
pre-merger notification laws or regulations of foreign jurisdictions have not
been obtained prior to termination of the Offer, or (iii) any of the following
events shall occur, or shall be deemed by Purchaser to have occurred, and be
continuing:

            (a) there shall be threatened in writing or pending any suit, action
or proceeding by any Governmental Entity or any third party against Purchaser,
Parent, the Company or any Company Subsidiary (i) seeking to prohibit or impose
any material limitations on Parent's or Purchaser's ownership or operation (or
that of any of their respective Subsidiaries or affiliates) of all or any
material portion of their or the Company's or the Company's Subsidiaries'
businesses or assets, taken as a whole, or to compel Parent or Purchaser or
their respective Subsidiaries or affiliates to dispose of or hold separate any
material portion of the business or assets of the Company or Parent or their
respective Subsidiaries, (ii) challenging the acquisition by Parent or Purchaser
of any Shares under the Offer, seeking to delay, restrain or prohibit the making
or consummation of the Offer or the Merger or the performance of any of the
other Transactions, or seeking to obtain from the Company, Parent or Purchaser
any damages that are material in relation to the Company and the Company's
Subsidiaries taken as a whole, (iii) seeking to impose material limitations on
the ability of Purchaser, or render Purchaser unable, to accept for payment, pay
for or purchase some or all of the Shares pursuant to the Offer or the Merger,
(iv) seeking to impose material limitations on the ability of Purchaser or
Parent effectively to exercise full rights of ownership of the Shares,
including, without limitation, the right to vote the Shares purchased by it on
all matters properly presented to the Company's stockholders, or (v) seeking to
require divestiture by Parent or any of its Subsidiaries or affiliates of any
Shares;

            (b) there shall be any statute, rule, regulation, judgment, order or
injunction enacted, entered, enforced, promulgated or deemed applicable,
pursuant to an authoritative interpretation by or on behalf of a Government
Entity, to the Offer, the Merger or any other

                                       54


Transaction, or any other action shall be taken by any Governmental Entity, that
is reasonably likely to result, directly or indirectly, in any of the
consequences referred to in clauses (i) through (v) of paragraph (a) above;

            (c) any of the representations and warranties of the Company
contained in this Agreement shall not be true and correct in all material
respects (other than representations and warranties qualified by materiality or
Material Adverse Effect, which shall be true and correct in all respects) as of
the date of this Agreement and as of the date of any scheduled expiration of the
Offer, except for representations and warranties that relate to a specific date
or time (which need only be true and correct in all material respects as of such
date or time) and except for those representations and warranties set forth in
Section 3.2 (which shall be true and correct in all respects, other than DE
MINIMIS variations);

            (d) since the date of this Agreement, there shall have occurred any
events or changes which have had, which are deemed to have had, or which are
reasonably likely to have or constitute, individually or in the aggregate, a
Material Adverse Effect on the Company;

            (e) the Company Board of Directors or any committee thereof shall
have (i) withdrawn, or modified or changed in a manner adverse to the
Transactions, to Parent or to Purchaser (including by amendment of the Schedule
14D-9), its recommendation of the Offer, the Merger Agreement, or the Merger or
shall have failed to make such favorable recommendation, (ii) approved or
recommended to its stockholders any Acquisition Proposal or entered into or
publicly announced its intention to enter into any agreement or agreement in
principle with respect to any Acquisition Proposal, (iii) resolved or publicly
proposed to do any of the foregoing or (iv) taken a neutral position or made no
recommendation with respect to an Acquisition Proposal (other than by Parent or
Purchaser) after a reasonable amount of time (and in no event more than five (5)
business days following receipt thereof) has elapsed for the Company Board of
Directors or any committee thereof to review and make a recommendation with
respect thereto;

            (f) any person or group (as defined in Section 13(d)(3) of the
Exchange Act) other than Parent or any of its subsidiaries shall have become the
beneficial owner (defined in Rule 13(d)(3) promulgated under the Exchange Act)
of more than twenty percent (20%) of the outstanding Shares or shall have
acquired, directly or indirectly, more than twenty percent (20%) of the assets
of the Company and its Subsidiaries;

            (g) the Company shall have breached or failed, in any material
respect, to perform or to comply with any material agreement, obligation or
covenant to be performed or complied with by it under this Agreement;

            (h) Purchaser shall have failed to receive a certificate executed by
the Company's Chief Executive Officer or President on behalf of the Company,
dated as of the scheduled expiration of the Offer, to the effect that the
conditions set forth in paragraphs (c), (d), (e), (f) and (g) of this Annex I
have not occurred;

            (i) the Merger Agreement shall have been terminated in accordance
with its terms;

                                       55


            (j) all consents, permits and approvals of Governmental Authorities
listed in Section 3.3 of the Company Disclosure Letter shall not have been
obtained; or

            (k) there shall have occurred and be continuing (i) a declaration by
a Governmental Entity of a banking moratorium or any suspension of payments in
respect of banks in the United States or (ii) a commencement of a war, armed
hostilities or other international or national calamity directly or indirectly
involving the United States, which precludes Parent's or Purchaser's
consummation of the Transactions.

            The foregoing conditions are for the sole benefit of Parent and
Purchaser, may be asserted by Parent or Purchaser regardless of the
circumstances giving rise to such condition, and may be waived by Parent or
Purchaser in whole or in part at any time and from time to time and in the sole
discretion of Parent or Purchaser, subject in each case to the terms of this
Agreement. The failure by Parent or Purchaser at any time to exercise any of the
foregoing rights shall not be deemed a waiver of any such right and, each such
right shall be deemed an ongoing right which may be asserted at any time and
from time to time.

            The capitalized terms used in this Annex I shall have the meanings
set forth in the Agreement to which it is annexed, except that the term "MERGER
AGREEMENT" shall be deemed to refer to the Agreement to which this Annex I is
annexed.

                                       56

EX-99.(D)(2)

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CONFIDENTIALITY AGREEMENT

        June 12, 2003

Genzme Corporation
One Kendal Square
Cambridge, MA 02139

        In connection with your consideration of a possible business combination transaction (a "Transaction") with SangStat Medical Corporation, we expect to make available to one another certain nonpublic information concerning our respective business, financial condition, operations, assets and liabilities, including, without limitation, technical information and information regarding intellectual property rights. As a condition to such information being furnished to each party and its directors, officers, employees, agents or advisors (including, without limitation, attorneys, accountants, consultants, bankers and financial advisors) (collectively, "Representatives"), each party agrees to treat any nonpublic information concerning to other party (whether prepared by the disclosing party, its advisors or otherwise and irrespective of the form of communication) which is furnished hereunder to a party or to its Representatives now or in the future by or on behalf of the disclosing party (herein collectively referred to as the "Evaluation Material") in accordance with the provisions of this Agreement.

        (1)    Evaluation Material.    The term "Evaluation Material" also shall be deemed to include all notes, analyses, compilations, studies, interpretations or other documents (whether in paper, electronic or any other form) prepared by each or its Representatives which contain, reflect or are based upon, in whole or in part, the information furnished to such party or its Representatives pursuant hereto which is not available to the general public and would otherwise constitute Evaluation Material hereunder. The term "Evaluation Material" does not include information which (i) is or becomes generally available to the public other than as a result of a breach of this Agreement by the receiving party or its Representatives, (ii) was within the receiving party's possession prior to its being furnished to the receiving party by or on behalf of the disclosing party, provided that the source of such information was not known by the receiving party to the bound by a confidentiality agreement with or other contractual, legal or fiduciary obligation of confidentiality to the disclosing party or any other party with respect to such information, (iii) is or becomes available to the receiving party on a non-confidential basis from a source other than the disclosing party or any of its Representatives, provided that such source was not known by the receiving party to be bound by a confidentiality agreement with or other contractual, legal or fiduciary obligation of confidentiality to the disclosing party or any other party with respect to such information, (iv) is disclosed by the disclosing party to a third party without a duty of confidentiality, (v) is independently developed by the receiving party or any of its Representatives without use of Evaluation Material and can be proved by competent evidence, (vi) is disclosed under operation of applicable law or regulation, or (vii) is disclosed by the receiving party or its Representatives with the discloser's prior written approval.

        (2)    Purpose of Disclosure of Evaluation Material.    It is understood and agreed to by each party that any exchange of information under this Agreement shall be solely for the purposes of evaluating a possible Transaction between the parties and, if the parties determine to proceed with a Transaction, the negotiation, execution and performance of a definitive agreement with respect thereto and not to affect, in any way, each party's relative competitive position to each party or to other entities. It is further agreed, that the information to be disclosed to each other shall only be that information which is reasonably necessary to a Transaction and that information which is not reasonably necessary for such purposes shall not be disclosed or exchanged. For purposes of determining when information is reasonably necessary for such purpose, legal counsel to each party shall agree, in advance, to review information requests so as to comply with such standard.

        (3)    Use of Evaluation Material.    Each party hereby agrees that it and its Representatives shall use the other's Evaluation Material solely for the purposes of evaluating a possible Transaction between the parties and, if the parties determine to proceed with a Transaction, the negotiation, execution and performance of a definitive agreement with respect thereto, and that the disclosing party's Evaluation

Material will be kept confidential and each party and its Representatives will not disclose or use for purposes other than the purposes stated above any of the other's Evaluation Material in any other manner whatsoever; provided, however, that (i) the receiving party may make any disclosure of such information to which the disclosing party gives its prior written consent and (ii) any of such information may be disclosed to the receiving party's Representatives which need to know such information for the sole purpose of evaluating a possible Transaction between the parties, who are informed of the confidential nature of such information and are subject to confidentiality and non-use obligations at least as restrictive as defined herein. Each party is aware of the restrictions imposed by the United States securities laws on the purchase or sale of securities by any person who have received material, nonpublic information from the issuer of such securities and on the communication of such information to any other person when it is reasonably foreseeable that such other person is likely to purchase or sell such securities in reliance upon such information.

        (4)    Non-Disclosure.    Subject to the above, each party agrees that, without the prior written consent of the other party, neither it nor its Representatives will disclose to any other person the fact that any Evaluation Material has been made available hereunder, that discussions or negotiations are taking place concerning a Transaction involving the parties or any of the terms, conditions or other facts with respect thereto (including that status thereof) provided, that a party may make such disclosure if such party determines,with the advice of counsel, that such disclosure is required by applicable law or regulation or under any listing agreement with respect to such party's securities. In such event, the disclosing party shall use its best efforts to give prompt advance written notice to the other party to the extent practicable under the circumstances.

        (5)    Required Disclosure.    In the event that a party or its Representatives are requested or required (by oral questions, interrogatories, requests for information or documents in legal proceedings, subpoena, civil investigative demand or other similar process) to disclose any of the other party's Evaluation Material, the party requested or required to make the disclosure shall provide the other party with prompt notice of any such request or requirement so that the other party may seek a protective order or other appropriate remedy and/or waive compliance with the provisions of this Agreement. If, in the absence of a protective order or other remedy or the receipt of a waiver by such other party, the party requested or required to make the disclosure or any of its Representatives are nonetheless, in the opinion of counsel, legally compelled to disclose the other party's Evaluation Material to any tribunal, the party requested or required to make the disclosure or its Representative may, without liability hereunder, disclose to such tribunal only that portion of the other party's Evaluation Material which such counsel advises is legally required to be disclosed, provided that the party requested or required to make the disclosure exercises its reasonable efforts to preserve the confidentiality of the other party's Evaluation Material, including, without limitation, by reasonably cooperating with the other party to obtain an appropriate protective order or other reliable assurance that confidential treatment will be accorded the other party's Evaluation Material by such tribunal.

        (6)    Termination of Discussions.    If either party decides that it does not wish to proceed with a Transaction with the other party, the party so deciding will inform the other party of that decision. In that case, or at any time upon the written request of either disclosing party for any reason, each receiving party will promptly deliver to the disclosing party or destroy all Evaluation Material that was furnished to the receiving party or its Representatives by or on behalf of the disclosing party, by whichever method requested by the disclosing party, pursuant hereto. In the event of such a decision for request, all other copies, extracts and summaries of the disclosing party's Evaluation Material prepared by the receiving party shall be destroyed and, except as provided herein, no copy thereof shall be retained. In no event shall the receiving party be obligated to disclose or provide the copies, extracts and summaries of the disclosing party's Evaluation Material prepared by it or its Representatives to the disclosing party. Notwithstanding the foregoing, the receiving party may retain one (1) copy of the disclosing party's Evaluation Material solely for purposes of monitoring its compliance with this

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Agreement. Notwithstanding the return or distruction of the Evaluation Material, each party and its Representatives will continue to be bound by its obligations of confidentiality and other obligations hereunder.

        (7)    No representation of Accuracy.    Each party understands and acknowledges that neither party nor any of its Representatives makes any representation or warranty, express or implied, as to the accuracy or completeness of the Evaluation Material make available by it or to it. Each party agrees that neither party nor any of its Representatives shall have any liability to the other party or to any of its Representatives relating to or resulting from the use of or reliance upon such other party's Evaluation Material or any errors therein or omissions therefrom. Only those representations or warranties which are made in a final definitive agreement regarding the Transaction, when, as and if executed, and subject to such limitations and restrictions as may be specified therein, will have any legal effect.

        (8)    Standstill.    Until the earlier to occur of (i) a Significant Event with respect to the other party and (ii) the date two (2) years form the date first set forth above, each party and its direct and undirect majority-owned and controlled subsidiaries will not (and each party and its direct and indirect majority-owned and controlled subsidiaries will not assist other to), directly or indirectly, without the prior consent of the other party:

        (a)   acquire or agree, offer, seek or propose to acquire, or cause to be acquired, ownership (including, but not limited to, beneficial ownership as defined in Rule 13d-3 under the Exchange Act) of any of the other party's so its subsidiaries' assets (other than in the ordinary course of business) or business or any voting securities issued by the other party which are, or may be, entitled to vote in the election of the other party's directors ("Voting Securities"), or any rights or options to acquire such ownership, including from a third party, other than pursuant to the Transaction; or

        (b)   make, or in any way participate in, any solicitation of proxies or consents with respect to any Voting Securities of the other party, become a participant in any proxy context with respect to the other party; or seek to advise or influence any person or entity with respect to the voting of any Voting Securities; or demand or copy of the other party's stock ledger, list of its stockholders or other books and records for purposes of any of the matters described in (a), (c), (d) or (e) or this clause (b); or call or attempt to call any meeting or the stockholders of the other party; or

        (c)   otherwise seek to control or influence the management, Board of Directors or policies of the other party; or

        (d)   enter into any discussions, negotiations, arrangements or understandings with any third party with respect to any of the matters described in (a), (b) or (c) above; or

        (e)   propose, attempt or announce an intention, to take any of the actions described in (a), (b), (c) or (d) above.

The term "Significant Event" means, with respect to either part, any of:

        (i)    the acquisition, or public announcement of an intention to acquire, by a person or "group" (as such term is used in Section 13(d)(3) of the Exchange Act) (a "13D Group") (not including the other party), by way of tender or exchange offer or otherwise, of voting securities representing ten percent (10%) or more of the then-outstanding voting securities of such party;

        (ii)   entry into a letter of intent or agreement by such party regarding any merger, sale, reorganization, recapitalization or other business combination transaction pursuant to which the outstanding shares of common stock of such party would be converted into cash or securities of a person or 13D Group (not including the other party) or twenty-five percent (25%) or more of the then-outstanding shares of common stock of such party would be owned by persons other than the

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then-current holders of shares of common stock of such party, or which would result in all or a substantial portion of such party's assets being sold to any person or 13D Group (not including the other party);

        (iii)  the making by such party of a public announcement of its determination to pursue (A) the sale or other disposition of a majority of the shares of such party's outstanding common stock, (B) the sale or disposition of all or substantially all of such party's assets or (C) a similar sale or change of control transaction; or

        (iv)  the material breach by such party of this Agreement.

        (9)    Duration of Confidentiality and Non-use Obligation.    The parties agree that the obligations pertaining to confidentiality and use of the Evaluation Material set forth in sections (2) through (6) above, and this clause (9), shall survive the expiration or termination of this Agreement until the expiration of the period ending five (5) years after the date first set forth above.

        (10)    No solicitation.    During the term of this Agreement, neither party shall, without the prior written consent of the other party, directly or indirectly solicit the employment of any employee of such other party, unless such employee seeks employment on an unsolicited basis or in response to general solicitations or advertising or third party employment agencies, provided that such general solicitations or advertising is made, taken out and distributed in the ordinary course and not in an effort to specifically target employees of the other party.

        (11)    Definitive Agreements.    Each party understands and agrees that no contract or agreement providing for any Transaction involving the parties shall be deemed to exist between the parties unless and until a final definitive agreement has been executed and delivered by the parties. Each party also agrees that unless and until a final definitive agreement regarding a Transaction between the parties has been executed and delivered, neither party will be under any legal obligation of any kind whatsoever with respect to such a Transaction by virtue of this Agreement except for the matters specifically agreed to herein. For purposes of this paragraph, the term "definitive agreement" does not include an executed letter of intent or any other preliminary written agreement. Both parties further acknowledge and agree that each party reserves the right, in its sole discretion, to provide or not provide Evaluation Material to the receiving party under this Agreement, to reject any any all proposals made by the other party or any of its Representatives with regard to a Transaction between the parties, and to terminate discussions and negotiations at any time.

        (12)    Waiver.    It is understood and agreed that no failure or delay by either party in exercising any right, power or privilege hereunder shall operate as a waiver thereof, nor shall any single or partial exercise thereof preclude any other or future exercise thereof or the exercise of any other right, power or privilege hereunder.

        (13)    Miscellaneous.    Each party agrees to be responsible for any breach of this Agreement by any of its Representatives. In case any provision of this Agreement shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions of this Agreement shall not in any way be affected or impaired thereby.

        (14)    Injunctive Relief.    It is further understood and agreed that money damages would not be sufficient remedy for any breach of this Agreement by either party or any of its Representatives and that the non-breaching party shall be entitled to seek to obtain equitable relief, including injunction and specific performance, as a remedy for any such breach. Such remedies shall not be deemed to be the exclusive remedies for a breach of this Agreement but shall be in addition to all other remedies available at law or equity. In the event of litigation relating to this Agreement, if a court of competent jurisdiction determines that either party or any of its Representatives have breached this Agreement, then the breaching party shall be liable and pay to the non-breaching party the reasonable legal fees

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incurred in connection with such litigation, including an appeal therefrom. In no event shall either party be liable for consequential or punitive damages.

        (15)    Governing Law; Forum.    This Agreement shall be governed by an construed in accordance with the laws of the State of New York applicable to agreements made and to be performed within such State. Any dispute between the parties arising out of or connected to this Agreement or its enforceability or interpretation, including any injunctive relief, shall be brought and resolved solely in the federal or state courts located within the Southern District of New York, and the parties hereby submit to the personal jurisdiction of said courts.

        (16)    Term.    Except as explicitly provided in sections (8) and (9) above, this Agreement shall terminate one (1) year from the date first set forth above.

        (17)    Counterparts.    This Agreement may be executed in two counterparts, which together shall be considered one and the same agreement and all become effective when such counterparts have been signed by each party and delivered to the other party, it being understood that all parties need not sign the same counterpart.

[Remainder of page intentionally left blank]

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        Please confirm your agreement with the foregoing by signing and returning one copy of this Agreement to the undersigned, whereupon this Confidentiality Agreement shall become a binding agreement between you and SangStat Medical Corporation.

Very truly yours, SANGSTAT MEDICAL CORPORATION
By:	/s/  ADRIAN ARIMA Name: Adrian Arima Title: Senior Vice President and General Counsel

Accepted and Agreed as of
the date first written above:

        GENZYME CORPORATION

By: /s/  RICHARD DOUGLAS Name:  Richard Douglas
Title:  Sr. V.P. Corporate Development

[SIGNATURE PAGE TO CONFIDENTIALITY AGREEMENT]

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