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                                                                   EXHIBIT 10.31

                            ACLARA BIOSCIENCES, INC.

                         COMMON STOCK ISSUANCE AGREEMENT


      THIS COMMON STOCK PURCHASE AGREEMENT (this "AGREEMENT") is made as of
March __, 2001 by and between ACLARA BIOSCIENCES, INC., a Delaware corporation
(the "COMPANY"), and Caliper Technologies Corp., a Delaware corporation
("CALIPER").

      WHEREAS, the Company and Caliper are concurrently entering into a
Settlement Agreement and General Mutual Release of even date herewith (the
"SETTLEMENT AGREEMENT"), which provides, among other things, that in
consideration for Caliper entering into the Settlement Agreement, the Company
will, among other things, issue to Caliper 900,000 shares (the "SHARES") of the
Company's common stock, $0.001 par value per share (the "COMMON STOCK"); and

      WHEREAS, the Company desires to issue, and Caliper desires to acquire, the
Shares.

      NOW THEREFORE, in consideration of the foregoing recitals and the terms
and covenants set forth herein, the parties hereby agree as follows:

      1. AUTHORIZATION AND ISSUANCE OF THE SHARES. Subject to the terms and
conditions of this Agreement, the Company has authorized the issuance of the
Shares to Caliper.

      2. AGREEMENT TO ISSUE AND ACQUIRE THE SHARES.

            2.1 At the Closing (as defined in Section 3), the Company will issue
to Caliper, and Caliper will acquire from the Company, upon the terms and
conditions hereinafter set forth, the Shares, as partial consideration for the
execution by Caliper of the Settlement Agreement. Caliper shall not be obligated
to pay any other consideration to the Company in respect of the Shares.

            2.2 Caliper acknowledges and agrees that issuance of the Shares to
Caliper and the performance of the Company's obligations under this Agreement
(including without limitation its payment obligations under Section 7.2)
satisfies in full the Company's obligation to pay $27.5 million and $5 million
in accordance with Sections 4(b) and 4(c) of the Settlement Agreement.

      3. DELIVERY OF THE SHARES AND LEGAL OPINION AT CLOSING. The completion of
the issuance of the Shares (the "CLOSING") shall occur (the "CLOSING DATE") on
or before the third business day after the date hereof, at the offices of the
Company's counsel. At the Closing, the Company shall deliver to Caliper (i) one
stock certificates representing the Shares, such certificate to be registered in
the name of Caliper, and (ii) a letter from Latham & Watkins in substantially
the form set forth herein as Exhibit B. The Company's obligation to issue the
Shares to Caliper shall be subject to the accuracy of the representations and
warranties made by Caliper.


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      4. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY. The Company
hereby represents and warrants to, and covenants with Caliper, as follows:

            4.1 ORGANIZATION. The Company is duly organized and validly existing
in good standing under the laws of the jurisdiction of its organization. The
Company has all corporate power and authority to own, operate and occupy its
properties and assets and to conduct its business as presently conducted and is
registered or qualified to do business and in good standing in each jurisdiction
in which it owns or leases property or transacts business and where the failure
to be so qualified would have a material adverse effect upon the business or
financial condition of the Company and no proceeding has been instituted in any
such jurisdiction, revoking, limiting or curtailing, or seeking to revoke, limit
or curtail, such power and authority or qualification.

            4.2 DUE AUTHORIZATION. The Company has all requisite corporate power
and authority to execute, deliver and perform its obligations under this
Agreement, and this Agreement has been duly authorized and validly executed and
delivered by the Company and constitutes a legal, valid and binding agreement of
the Company enforceable against the Company in accordance with its terms, except
as rights to indemnity and contribution may be limited by state or federal
securities laws or the public policy underlying such laws, except as
enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting creditors' and contracting
parties' rights generally and except as enforceability may be subject to general
principles of equity (regardless of whether such enforceability is considered in
a proceeding in equity or at law).

            4.3 NON-CONTRAVENTION. The execution and delivery of this Agreement,
the issuance and sale of the Shares to be sold by the Company under this
Agreement, the fulfillment of the terms of this Agreement and the consummation
of the transactions contemplated thereby will not (A) conflict with or
constitute a violation of, or default (with or without the giving of notice or
the passage of time or both) under, (i) any material bond, debenture, note or
other evidence of indebtedness, or under any material lease, contract,
indenture, mortgage, deed of trust, loan agreement, joint venture or other
agreement or instrument to which the Company is a party or by which it or its
properties or assets are bound, (ii) the charter, by-laws or other
organizational documents of the Company, or (iii) any law, administrative
regulation, ordinance or order of any court or governmental agency, arbitration
panel or authority applicable to the Company or its properties or assets, or (B)
result in the creation or imposition of any lien, encumbrance, claim, security
interest or restriction whatsoever upon any of the material properties or assets
of the Company or an acceleration of indebtedness pursuant to any obligation,
agreement or condition contained in any material bond, debenture, note or any
other evidence of indebtedness or any material indenture, mortgage, deed of
trust or any other agreement or instrument to which the Company is a party or by
which any of it or its properties or assets are bound or to which any of the
property or assets of the Company is subject. No consent, approval,
authorization or other order of, or registration, qualification or filing with,
any regulatory body, administrative agency, or other governmental body in the
United States is required for the execution and delivery of this Agreement and
the valid issuance and sale of the Shares to be sold pursuant to this Agreement,
other than such as have been made or obtained, and except for any securities
filings required to be made under federal or state securities laws.


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            4.4 REPORTING STATUS. The Company has filed in a timely manner all
documents that the Company was required to file under the Securities Exchange
Act of 1934, as amended (the "EXCHANGE ACT"), during the 12 months preceding the
date of this Agreement. Such documents (including, without limitation, all
exhibits included or incorporated by reference therein) complied in all material
respects with the requirements of the Securities and Exchange Commission (the
"SEC") as of their respective filing dates, and the information contained
therein as of the date thereof did not contain an untrue statement of a material
fact or omit to state a material fact required to be stated therein or necessary
to make the statements therein in light of the circumstances under which they
were made not misleading, except to the extent that information contained in any
such document has been revised or superseded by a later filed "SEC Document",
which shall mean any document filed by the Company with the SEC since December
31, 1999 pursuant to the reporting requirements of the Exchange Act, including
the Company's Quarterly Reports on Form 10-Q for the quarters ended March 31,
2000 and June 30, 2000 and September 30, 2000.

            4.5 CAPITALIZATION. As of the date hereof, the authorized capital
stock of the Company consists of 150,000,000 shares of Common Stock and
15,000,000 shares of preferred stock, par value $0.001 per share, of the Company
(the "PREFERRED STOCK"). As of December 31, 2000, there were approximately
34,527,670 shares of Common Stock issued and outstanding, and no shares of the
Preferred Stock issued and outstanding. The Shares to be issued pursuant to this
Agreement have been duly authorized, and when issued in accordance with the
terms of this Agreement will be duly and validly issued, fully paid and
nonassessable. No preemptive right, co-sale right, right of first refusal or
other similar right exists with respect to the Shares or the issuance and sale
thereof.

            4.6 LEGAL PROCEEDINGS. Except for proceedings related to the
execution of the Settlement Agreement, there is no material legal or
governmental proceeding pending or, to the knowledge of the Company, threatened
to which the Company is or may be a party or of which the business, property or
assets of the Company is subject that is not disclosed in the SEC Documents.

            4.7 NO VIOLATIONS. The Company is not (i) in violation of its
charter, bylaws, or other organizational document, or in violation of any law,
administrative regulation, ordinance or order of any court or governmental
agency, arbitration panel or authority applicable to the Company, which
violation, individually or in the aggregate, would be reasonably likely to have
a material adverse effect on the business or financial condition of the Company
or (ii) in default (and there exists no condition which, with or without the
passage of time or giving of notice or both, would constitute a default) in any
material respect in the performance of any bond, debenture, note or any other
evidence of indebtedness in any indenture, mortgage, deed of trust or any other
material agreement or instrument to which the Company is a party or by which the
Company is bound or by which the properties or assets of the Company are bound,
which would be reasonably likely to have a material adverse effect upon the
business or financial condition of the Company.

            4.8 NASDAQ LISTING. The Company's Common Stock is registered
pursuant to Section 12(g) of the Exchange Act and is listed, and currently
complies with the requirements for continued listing, on The Nasdaq Stock
Market, Inc. National Market (the "NASDAQ NATIONAL


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MARKET"), and the Company has taken no action designed to, or likely to have the
effect of, terminating the registration of the Common Stock under the Exchange
Act or de-listing the Common Stock from the Nasdaq National Market, nor to the
Company's knowledge is the National Association of Securities Dealers, Inc.
currently contemplating terminating such listing.

            4.9 LISTING OF THE SHARES. The Company shall comply with all
requirements of the National Association of Securities Dealers, Inc. with
respect to the issuance of the Shares and the listing thereof on the Nasdaq
National Market

            4.10 S-3 STATUS. Except for the requirement set forth in General
Instruction I.A.3.(a) of Form S-3 requiring that a registrant be subject to the
requirements of Section 12 of 15(d) of the Securities and Exchange Act of 1934
for a period of at least 12 calendar months immediately preceding the filing of
the registration statement, the Company would meet the requirements for the use
of Form S-3 for the registration of the resale of the Shares by Caliper. The
Company will use its best efforts to meet the requirements for the use of Form
S-3 for the registration of the resale of the Shares by Caliper. Once the
Company has become eligible to use Form S-3, it will use its best efforts to
maintain S-3 status with the SEC during the Registration Period (as defined in
Section 6.1(c)).

            4.11 NO REGISTRATION. Assuming the accuracy of the representations
and warranties made by, and compliance with the covenants of, Caliper in Section
5 hereof, no registration of the Shares under the Securities Act of 1933, as
amended (the "SECURITIES ACT"), is required in connection with the offer and
sale of the Shares by the Company to Caliper as contemplated by this Agreement.

            4.12 FORM D. The Company agrees to file one or more Forms D with
respect to the Shares as required under Regulation D under the Securities Act to
claim the exemption provided by Rule 506 of Regulation D.

      5. REPRESENTATIONS, WARRANTIES AND COVENANTS OF CALIPER.

            5.1 ACCREDITED INVESTOR. Caliper represents and warrants to, and
covenants with, the Company that: (i) Caliper is an "accredited investor" as
defined in Regulation D under the Securities Act and Caliper has the knowledge,
sophistication and experience necessary to make, and is qualified to make
decisions with respect to, investments in shares presenting an investment
decision like that involved in the purchase of the Shares, including investments
in securities issued by the Company and investments in comparable companies, and
has requested, received, reviewed and considered all information it deemed
relevant in making an informed decision to purchase the Shares; (ii) Caliper is
acquiring the Shares for its own account for investment only and with no present
intention of distributing any of such Shares or any arrangement or understanding
with any other persons regarding the distribution, sale or transfer of such
Shares; (iii) Caliper will not, directly or indirectly, offer, sell, pledge,
transfer or otherwise dispose of (or solicit any offers to buy, purchase or
otherwise acquire or take a pledge of) any Registrable Shares (as defined in
Section 6.1(a) hereof) except in compliance with the Securities Act, applicable
state securities laws and the respective rules and regulations promulgated
thereunder; (iv) Caliper (A) has had no position, office or other material
relationship within the past three years with the Company or its affiliates (B)
neither it, nor any


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group of which it is a member or to which it is related, beneficially owns
(including the right to acquire or vote) any securities of the Company and (C)
it has no direct or indirect affiliation or association with any NASD member;
(v) Caliper will notify the Company immediately of any change in any of such
information on Schedule 5.1 until such time as Caliper has sold all of its
Registrable Shares or until the Company is no longer required to keep the
Registration Statement effective; and (vi) Caliper has, in connection with its
decision to acquire the Shares, had access to the SEC Documents and has had a
reasonable opportunity to ask questions of and receive answers from a person or
persons acting on behalf of the Company concerning the offering of the Shares
and all such questions have answered to the full satisfaction of Caliper.
Caliper understands that its acquisition of the Shares has not been registered
under the Securities Act or registered or qualified under any state securities
law in reliance on specific exemptions therefrom, which exemptions may depend
upon, among other things, the bona fide nature of Caliper's investment intent as
expressed herein. Caliper further understands that the Shares are "restricted
securities" under applicable federal and state securities laws and that,
pursuant to these laws, Caliper must hold the Shares indefinitely unless they
are registered under the Securities Act, or an exemption from such registration
requirements is available. Caliper acknowledges that, except as specifically
provided for in this Agreement, the Company has no obligation to register or
qualify the Shares for resale. Caliper further acknowledges that if an exemption
from registration or qualification is available, it may be conditioned on
various requirements including, but not limited to, the time and manner of sale,
the holding period for the Shares, and requirements relating to the Company
which are outside of Caliper's control, and which the Company is under no
obligation and may not be able to satisfy.

            5.2 NO FOREIGN OFFERING. Caliper acknowledges, represents and agrees
that no action has been or will be taken in any jurisdiction outside the United
States by the Company that would permit an offering of the Shares, or possession
or distribution of offering materials in connection with the issue of the
Shares, in any jurisdiction outside the United States where action for that
purpose is required. If Caliper is located or domiciled outside the United
States it agrees to comply with all applicable laws and regulations in each
foreign jurisdiction in which it purchases, offers, sells or delivers Shares or
has in its possession or distributes any offering material, in all cases at its
own expense.

            5.3 LEGENDS; TRANSFER.

                  (a) LEGENDS. Until the Registrable Shares have been registered
on an effective registration statement, the certificate or certificates
representing the Registrable Shares shall bear legends in substantially the
following form (as well as any legends required by applicable state and federal
corporate and securities laws):

      THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AND HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT
WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF. NO SUCH
SALE OR DISTRIBUTION MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT
RELATED THERETO OR AN OPINION OF COUNSEL IN A FORM SATISFACTORY TO THE COMPANY
THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT OF 1933.


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                  (b) STOP-TRANSFER NOTICES. Caliper agrees that, in order to
ensure compliance with the restrictions referred to herein, the Company may
issue appropriate "stop transfer" instructions to its transfer agent, if any,
and that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.

                  (c) REFUSAL TO TRANSFER. The Company shall not be required (i)
to transfer on its books any Registrable Shares that have been sold or otherwise
transferred in violation of any of the provisions of this Agreement or (ii) to
treat as owner of such Registrable Shares or to accord the right to vote or pay
dividends to any purchaser or other transferee to whom such Registrable Shares
shall have been so transferred.

                  (d) ALL TRANSFERS OF THE REGISTRABLE SHARES TO BE EFFECTED VIA
DEUTSCHE BANC ALEX. BROWN. In order to ensure timely and prompt compliance by
the parties hereto with the provisions of this Agreement, including without
limitation, the provisions of Section 7 hereof, the parties hereto agree that
all transfers and sales of any of the Registrable Shares by Caliper shall be
effected through the brokerage services department of Deutsche Banc Alex. Brown
(or such other broker as may be designated from time to time by the Company).

            5.4 POWER AND AUTHORITY. Caliper further represents and warrants to
the Company that (i) Caliper has full right, power, authority and capacity to
enter into this Agreement and to consummate the transactions contemplated hereby
and has taken all necessary action to authorize the execution, delivery and
performance of this Agreement and (ii) this Agreement constitutes a valid and
binding obligation of Caliper enforceable against Caliper in accordance with its
terms, except as rights to indemnity and contribution may be limited by state or
federal securities laws or the public policy underlying such laws, and except as
enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting creditors' and contracting
parties' rights generally and except as enforceability may be subject to general
principles of equity (regardless of whether such enforceability is considered in
a proceeding in equity or at law).

            5.5 TAXES. Caliper understands that nothing in this Agreement or any
other materials presented to Caliper in connection with the purchase and sale of
the Shares constitutes legal, tax or investment advice. Caliper has consulted
such legal, tax and investment advisors as it, in its sole discretion, has
deemed necessary or appropriate in connection with its purchase of Shares.
Caliper further agrees that it will be solely responsible for the withholding
and/or payment of any federal, state, or local taxes with respect to the Shares
issued to it hereunder, and it will indemnify and hold the Company harmless from
all liability related to the tax treatment of the Shares.

            5.6 AGREEMENT TO VOTE SHARES. In all stockholder actions and for so
long as Caliper holds any of the Registrable Shares, Caliper agrees to vote the
Registrable Shares in the manner recommended by the Company's Board of
Directors, except to the extent prohibited by applicable law.


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      6. REGISTRATION OF THE SHARES; COMPLIANCE WITH THE SECURITIES ACT.

            6.1 REGISTRATION PROCEDURES AND EXPENSES. The Company shall:

                  (a) subject to receipt of necessary information from Caliper,
prepare and file with the SEC, within 60 days after the Closing Date, a
registration statement (the "REGISTRATION STATEMENT") on Form S-3 (or if Company
does not qualify for Form S-3 on March 31, 2001, on Form S-1 or Form S-2) to
enable the resale of the Registrable Shares (as defined below) by Caliper on a
delayed or continuous basis under Rule 415 of the Securities Act. "Registrable
Shares" means (i) the Shares and (ii) any shares of capital stock issued or
issuable, from time to time, upon any reclassification, share combination, share
subdivision, stock split, share dividend, merger, consolidation or similar
transaction or event or otherwise as a distribution on, in exchange for, in
replacement of, or with respect to any of the foregoing, in each case held at
the relevant time by Caliper;

                  (b) use its best efforts, subject to receipt of necessary
information from Caliper, to cause the Registration Statement to become
effective within 90 days after the Closing Date;

                  (c) prepare and file with the SEC such amendments and
supplements to the Registration Statement and the Prospectus used in connection
therewith and take all such other actions as may be necessary to keep the
Registration Statement current and effective for a period (the "REGISTRATION
PERIOD") commencing on the effective date of the Registration Statement and
ending on the earlier of (i) the second anniversary of the effective date of the
Registration Statement, (ii) the date on which Caliper may sell all Registrable
Shares then held by Caliper under Rule 144(k) of the Securities Act, and (iii)
such time as all Registrable Shares held by Caliper have been sold (A) pursuant
to a registration statement, (B) to or through a broker or dealer or underwriter
in a public distribution or a public securities transaction, and/or (C) in a
transaction exempt from the registration and prospectus delivery requirements of
the Securities Act under Section 4(1) thereof so that all transfer restrictions
and restrictive legends with respect thereto, if any, are removed upon the
consummation of such sale;

                  (d) furnish to Caliper with respect to the Registrable Shares
registered under the Registration Statement such number of copies of the
Registration Statement, Prospectuses and Preliminary Prospectuses in conformity
with the requirements of the Securities Act and such other documents as Caliper
may reasonably request, in order to facilitate the public sale or other
disposition of all or any of the Registrable Shares by Caliper; provided
however, that the obligation of the Company to deliver copies of Prospectuses or
Preliminary Prospectuses to Caliper shall be subject to receipt by the Company
of reasonable assurances from Caliper that Caliper will comply with the
applicable provisions of the Securities Act and of such other securities or blue
sky laws as may be applicable in connection with any use of such Prospectuses or
Preliminary Prospectuses;

                  (e) take such action as may be necessary to register, qualify
or obtain an exemption for the Registrable Shares under such of the state
securities laws of United States jurisdictions as shall be necessary to qualify,
or obtain an exemption for, the sale of the Registrable Shares in states
specified in writing by Caliper; provided, however, that the


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Company shall not be required to qualify to do business or consent to service of
process in any jurisdiction in which it is not now so qualified or has not so
consented;

                  (f) advise Caliper promptly, (i) after it shall receive notice
or obtain knowledge of the issuance of any stop order by the SEC delaying or
suspending the effectiveness of the Registration Statement or of the initiation
or threat of any proceeding for that purpose, and it will promptly use its
commercially reasonable efforts to prevent the issuance of any stop order to
obtain its withdrawal at the earliest possible moment if such stop order should
be issued or other order should be issued; (ii) when the Prospectus or any
Prospectus Supplement or post-effective amendment has been filed, and, with
respect to the Registration Statement or any post-effective amendment thereto,
when the same has become effective; and (iii) after the Company shall receive
notice or obtain knowledge of the existence of any fact or the happening of any
event that makes any statement of a material fact made in the Registration
Statement, the Prospectus, any amendment or supplement thereto, or any document
incorporated by reference therein untrue, or that requires the making of any
additions to or changes in the Registration Statement or the Prospectus in order
to make the statements therein not misleading;

                  (g) otherwise use its best efforts to comply with all
applicable rules and regulations of the SEC;

                  (h) bear all expenses in connection with the procedures in
paragraphs (a) through (g) of this Section 6.1 and the registration of the
Registrable Shares pursuant to the Registration Statement.

            6.2 TRANSFER OF SHARES; SUSPENSION.

                  (a) Caliper agrees that it will not effect any sale, offer to
sell, solicitation of offers to buy, disposition of, loan, pledge or grant of
any right with respect to (each, a "DISPOSITION") the Registrable Shares or its
right to purchase the Registrable Shares that would constitute a sale within the
meaning of the Securities Act except as contemplated in the Registration
Statement referred to in Section 6.1 and as described below or otherwise in
accordance with the Securities Act, and that it will promptly notify the Company
of any changes in the information set forth in the Registration Statement
regarding Caliper or its plan of distribution.

                  (b) Except in the event that paragraph (c) below applies, the
Company shall, (i) if deemed necessary by the Company, prepare and file from
time to time with the SEC a post-effective amendment to the Registration
Statement or a supplement to the related Prospectus or a supplement or amendment
to any document incorporated therein by reference or file any other required
document so that such Registration Statement will not contain an untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein not misleading, and
so that, as thereafter delivered to purchasers of the Registrable Shares being
sold thereunder, such Prospectus will not contain an untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading; (ii) provide Caliper copies of any
documents filed pursuant to Section 6.2(b)(i); and (iii) inform Caliper that the
Company has complied with its obligations in Section


                                       8.
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6.2(b)(i) (or that, if the Company has filed a post-effective amendment to the
Registration Statement which has not yet been declared effective, the Company
will notify Caliper to that effect, will use its commercially reasonable efforts
to secure the effectiveness of such post-effective amendment as promptly as
possible and will promptly notify Caliper pursuant to Section 6.2(b)(i) hereof
when the amendment has become effective).

                  (c) Subject to paragraph (d) below, in the event (i) of any
request by the SEC or any other federal or state governmental authority during
the period of effectiveness of the Registration Statement for amendments or
supplements to a Registration Statement or related Prospectus or for additional
information; (ii) of the issuance by the SEC or any other federal or state
governmental authority of any stop order suspending the effectiveness of a
Registration Statement or the initiation of any proceedings for that purpose;
(iii) of the receipt by the Company of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the
Registrable Shares for sale in any jurisdiction or the initiation or threatening
of any proceeding for such purpose; or (iv) of any event or circumstance which
necessitates the making of any changes in the Registration Statement or
Prospectus, or any document incorporated or deemed to be incorporated therein by
reference, so that, in the case of the Registration Statement, it will not
contain any untrue statement of a material fact or any omission to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading, and that in the case of the Prospectus, it will not
contain any untrue statement of a material fact or any omission to state a
material fact required to be stated therein or necessary to make the statements
therein, in the light of the circumstances under which they were made, not
misleading; then the Company shall deliver a certificate in writing to Caliper
(the "SUSPENSION NOTICE") to the effect of the foregoing and, upon receipt of
such Suspension Notice, Caliper will refrain from selling any Registrable Shares
pursuant to the Registration Statement (a "SUSPENSION") until Caliper's receipt
of copies of a supplemented or amended Prospectus prepared and filed by the
Company, or until it is advised in writing by the Company that the current
Prospectus may be used, and has received copies of any additional or
supplemental filings that are incorporated or deemed incorporated by reference
in any such Prospectus. In the event of any Suspension, the Company will use its
commercially reasonable efforts to cause the use of the Prospectus so suspended
to be resumed as soon as reasonably practicable after the delivery of a
Suspension Notice to Caliper. In addition to and without limiting any other
remedies (including, without limitation, at law or at equity) available to
Caliper, Caliper shall be entitled to specific performance in the event that the
Company fails to comply with the provisions of this Section 6.2(c).

                  (d) Notwithstanding the foregoing paragraphs of this Section
6.2, Caliper shall not be prohibited from selling Registrable Shares under the
Registration Statement as a result of Suspensions on more than two occasions of
not more than 20 days each in any twelve month period, unless, in the good faith
judgment of the Company's Board of Directors, upon advice of counsel, the sale
of Registrable Shares under the Registration Statement in reliance on this
paragraph 6.2(d) would be reasonably likely to cause a violation of the
Securities Act or the Exchange Act and result in potential liability to the
Company.

                  (e) Provided that a Suspension is not then in effect, Caliper
may sell Registrable Shares under the Registration Statement, provided that it
arranges for delivery of a current Prospectus to the transferee of such Shares.


                                       9.
<PAGE>   10

                  (f) In the event of a sale of Registrable Shares by Caliper
under the Registration Statement, Caliper shall deliver to the Company's
transfer agent, with a copy to the Company, a Certificate of Subsequent Sale
substantially in the form attached hereto as Exhibit A, so that the Registrable
Shares may be properly transferred.

            6.3 INDEMNIFICATION.

                  (a) For the purpose of this Section 6.3:

                        (i) the term "Registration Statement" shall include any
final Prospectus, exhibit, supplement or amendment included in or relating to
the Registration Statement referred to in Section 6.1; and

                        (ii) the term "untrue statement" shall include any
untrue statement or alleged untrue statement, or any omission or alleged
omission to state in the Registration Statement or Prospectus a material fact
required to be stated therein or necessary to make the statements therein, in
the light of the circumstances under which they were made, not misleading.

                  (b) The Company agrees to indemnify and hold harmless Caliper,
the officers, directors and any underwriter (as defined in the Securities Act)
of Caliper, and each person, if any, who controls Caliper or such underwriter
within the meaning of the Securities Act or the Exchange Act, from and against
any losses, claims, damages or liabilities to which Caliper may become subject
(under the Securities Act or otherwise) insofar as such losses, claims, damages
or liabilities (or actions or proceedings in respect thereof) arise out of, or
are based upon (i) any untrue statement of a material fact contained in the
Registration Statement, or (ii) any failure by the Company to fulfill any
undertaking included in the Registration Statement, or (iii) any violation or
alleged violation by the Company of the Securities Act, the Exchange Act or any
rule or regulation promulgated under the Securities Act or the Exchange Act, and
the Company will reimburse Caliper for any reasonable legal or other expenses
reasonably incurred in investigating, defending or preparing to defend any such
action, proceeding or claim, or preparing to defend any such action, proceeding
or claim, provided, however, that the Company shall not be liable in any such
case to the extent that such loss, claim, damage or liability arises out of, or
is based upon, an untrue statement made in such Registration Statement in
reliance upon and in conformity with written information furnished to the
Company by or on behalf of Caliper specifically for use in preparation of the
Registration Statement or the failure of Caliper to comply with its covenants
and agreements contained in Sections 5.3 or 6.2 hereof respecting sale of the
Registrable Shares or any statement or omission in any Prospectus that is
corrected in any subsequent Prospectus that was delivered to Caliper prior to
the pertinent sale or sales by Caliper.

                  (c) Caliper agrees to indemnify and hold harmless the Company,
the officers and directors of the Company, and each person, if any, who controls
the Company within the meaning of the Securities Act or the Exchange Act from
and against any losses, claims, damages or liabilities to which the Company (or
any such officer, director or controlling person) may become subject (under the
Securities Act or otherwise), insofar as such losses, claims, damages or
liabilities (or actions or proceedings in respect thereof) arise out of, or are


                                      10.
<PAGE>   11

based upon, (i) any failure to comply with the covenants and agreements
contained in Section 5.3 or 6.2 hereof respecting sale of the Shares, or (ii)
any untrue statement of a material fact contained in the Registration Statement
if such untrue statement was made in reliance upon and in conformity with
written information furnished by or on behalf of Caliper specifically for use in
preparation of the Registration Statement, and Caliper will reimburse the
Company (or such officer, director or controlling person), as the case may be,
for any legal or other expenses reasonably incurred in investigating, defending
or preparing to defend any such action, proceeding or claim. Notwithstanding the
foregoing, Caliper's liability pursuant to this subsection (b) shall be limited
to the net amount received by Caliper from the sale of the Shares, unless such
liability resulted from gross negligence or willful misconduct by Caliper.

                  (d) Promptly after receipt by any indemnified person of a
notice of a claim or the beginning of any action in respect of which indemnity
is to be sought against an indemnifying person pursuant to this Section 6.3,
such indemnified person shall notify the indemnifying person in writing of such
claim or of the commencement of such action, but the omission to so notify the
indemnifying party will not relieve it from any liability which it may have to
any indemnified party under this Section 6.3 (except to the extent that such
omission materially and adversely affects the indemnifying party's ability to
defend such action) or from any liability otherwise than under this Section 6.3.
Subject to the provisions hereinafter stated, in case any such action shall be
brought against an indemnified person, the indemnifying person shall be entitled
to participate therein, and, to the extent that it shall elect by written notice
delivered to the indemnified party promptly after receiving the aforesaid notice
from such indemnified party, shall be entitled to assume the defense thereof,
with counsel reasonably satisfactory to such indemnified person. After notice
from the indemnifying person to such indemnified person of its election to
assume the defense thereof, such indemnifying person shall not be liable to such
indemnified person for any legal expenses subsequently incurred by such
indemnified person in connection with the defense thereof, provided, however,
that if there exists or shall exist a conflict of interest that would make it
inappropriate, in the opinion of counsel to the indemnified person, for the same
counsel to represent both the indemnified person and such indemnifying person or
any affiliate or associate thereof, the indemnified person shall be entitled to
retain its own counsel at the expense of such indemnifying person; provided,
however, that no indemnifying person shall be responsible for the fees and
expenses of more than one separate counsel (together with appropriate local
counsel) for all indemnified parties. In no event shall any indemnifying person
be liable in respect of any amounts paid in settlement of any action unless the
indemnifying person shall have approved the terms of such settlement; provided
that such consent shall not be unreasonably withheld. No indemnifying person
shall, without the prior written consent of the indemnified person, effect any
settlement of any pending or threatened proceeding in respect of which any
indemnified person is or could have been a party and indemnification could have
been sought hereunder by such indemnified person, unless such settlement
includes an unconditional release of such indemnified person from all liability
on claims that are the subject matter of such proceeding.

                  (e) If the indemnification provided for in this Section 6.3 is
unavailable to or insufficient to hold harmless an indemnified party under
subsection (a) or (b) above in respect of any losses, claims, damages or
liabilities (or actions or proceedings in respect thereof) referred to therein,
then each indemnifying party shall contribute to the amount paid or payable by
such indemnified party as a result of such losses, claims, damages or
liabilities (or


                                      11.
<PAGE>   12

actions in respect thereof) in such proportion as is appropriate to reflect the
relative fault of the Company on the one hand and Caliper on the other in
connection with the statements or omissions or other matters which resulted in
such losses, claims, damages or liabilities (or actions in respect thereof), as
well as any other relevant equitable considerations. The relative fault shall be
determined by reference to, among other things, in the case of an untrue
statement, whether the untrue statement relates to information supplied by the
Company on the one hand or Caliper on the other and the parties' relative
intent, knowledge, access to information and opportunity to correct or prevent
such untrue statement. The Company and Caliper agree that it would not be just
and equitable if contribution pursuant to this subsection (d) were determined by
pro rata allocation (even if Caliper were treated as one entity for such
purpose) or by any other method of allocation which does not take into account
the equitable considerations referred to above in this subsection (d). The
amount paid or payable by an indemnified party as a result of the losses,
claims, damages or liabilities (or actions in respect thereof) referred to above
in this subsection (d) shall be deemed to include any legal or other expenses
reasonably incurred by such indemnified party in connection with investigating
or defending any such action or claim. Notwithstanding the provisions of this
subsection (d), Caliper shall not be required to contribute any amount in excess
of the net amount received by Caliper from the sale of the Shares. No person
guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of
the Securities Act) shall be entitled to contribution from any person who was
not guilty of such fraudulent misrepresentation.

                  (f) The parties to this Agreement hereby acknowledge that they
are sophisticated business persons who were represented by counsel during the
negotiations regarding the provisions hereof including, without limitation, the
provisions of this Section 6.3, and are fully informed regarding said
provisions.

      They further acknowledge that the provisions of this Section 6.3 fairly
allocate the risks in light of the ability of the parties to investigate the
Company and its business in order to assure that adequate disclosure is made in
the Registration Statement as required by the Act and the Exchange Act. The
parties are advised that federal or state public policy as interpreted by the
courts in certain jurisdictions may be contrary to certain of the provisions of
this Section 6.3, and the parties hereto hereby expressly waive and relinquish
any right or ability to assert such public policy as a defense to a claim under
this Section 6.3 and further agree not to attempt to assert any such defense.

            6.4 TERMINATION OF CONDITIONS AND OBLIGATIONS. The conditions
precedent imposed by Section 5 or this Section 6 upon Dispositions of the
Registrable Shares by Caliper shall cease and terminate as to any particular
number of the Registrable Shares when such Registrable Shares shall have been
effectively registered under the Securities Act and sold or otherwise disposed
of in accordance with the intended method of disposition set forth in the
Registration Statement covering such Registrable Shares or at such time as an
opinion of counsel reasonably satisfactory to the Company shall have been
rendered to the effect that such conditions are not necessary in order to comply
with the Securities Act (provided that such opinion shall not be required if the
Company shall be furnished with written documentation reasonably satisfactory to
it that such Registrable Shares are being transferred in a customary transaction
exempt from registration under Rule 144 under the Securities Act).


                                      12.
<PAGE>   13

      7. CERTAIN DISPOSITIONS OF THE REGISTRABLE SHARES FOLLOWING 18-MONTH
ANNIVERSARY.

            7.1 DEFINITIONS. For purposes of this Section 7, the following
definitions shall apply;

                  (a) "BUSINESS DAY" shall have the meaning given it in the
Letter of Credit (as defined in Section 8).

                  (b) "COVERED SHARES" means, on any date, Registrable Shares
which, as of such date are not Uncovered Shares.

                  (c) "FAIR MARKET VALUE" means, as of a particular date, the
value of Common Stock determined as follows:

                        (i) If the Common Stock is listed on any established
stock exchange or a national market system, including without limitation the
Nasdaq National Market of the National Association of Securities Dealers, Inc.
Automated Quotation ("Nasdaq") System, the Fair Market Value of a share of
Common Stock shall be the closing sales price for such stock (or the closing
bid, if no sales were reported) as quoted on such system or exchange (or the
exchange with the greatest volume of trading in Common Stock) on the market
trading day prior to such date, as reported in The Wall Street Journal;

                        (ii) If the Common Stock is quoted on the Nasdaq System
(but not on the Nasdaq National Market thereof) or is regularly quoted by a
recognized securities dealer but selling prices are not reported, the Fair
Market Value of a share of Common Stock shall be the mean between the high bid
and low asked prices for the Common Stock on the market trading day prior to
such date, as reported in The Wall Street Journal;

                        (iii) In the absence of an established market for the
Common Stock, the Fair Market Value shall be determined by a
nationally-recognized investment banking firm chosen by the Board of Directors
of the Company, subject to the approval of Caliper (which approval shall not be
unreasonably withheld).

                  (d) "HOLDING PERIOD" shall mean the period beginning on the
effective date of the Registration Statement and ending on August 21, 2002.

                  (e) "MINIMUM PRICE" shall mean $36.11, as adjusted for any
increase or decrease in the number of issued shares of Common Stock resulting
from a stock split, reverse stock split, stock dividend, combination or
reclassification of the Common Stock, any exchange ratio in connection with any
merger, exchange offer or other business combination, or other similar event
occurring after the date hereof.

                  (f) "THRESHOLD NUMBER" for any day means 15% of the average of
the daily trading volume of the Common Stock as published in The Wall Street
Journal for the twenty (20) trading days preceding such day.


                                      13.
<PAGE>   14

                  (g) "UNCOVERED SHARES" means, on any date, Registrable Shares
with respect to which the Company's obligation to pay the Difference pursuant to
Section 7.2 has been deemed satisfied under and pursuant to the provisions of
Section 7.3(a).

            7.2 CERTAIN DISPOSITIONS. Subject to Section 7.3:

                  (a) If, at any time after August 21, 2002 but before February
21, 2003 Caliper provides notice (the "NOTICE OF DISPOSITION") to the Company
that Caliper desires to effect a Disposition of Covered Shares (which Notice of
Disposition shall include the date of the proposed disposition (the "PROPOSED
DISPOSITION DATE"), the number of Covered Shares proposed to be disposed of and
shall be delivered to the Company no less than ten (10) Business Days before the
Proposed Disposition Date), the Company may elect to repurchase such Covered
Shares by providing notice of such election to Caliper within five (5) Business
Days from receipt of the Notice of Disposition.

                  (b) If Company elects to repurchase such Covered Shares, on
the Proposed Disposition Date, Caliper shall deliver such Covered Shares to the
Company upon receipt from the Company, by wire transfer of immediately available
funds, of an amount equal to (i) the Fair Market Value on the Proposed
Disposition Date multiplied by the number of Covered Shares repurchased plus
(ii) the positive difference, if any, between the Minimum Price and Fair Market
Value on the Proposed Disposition Date multiplied by the number of Covered
Shares repurchased.

                  (c) If Company does not elect to repurchase such Covered
Shares, Company shall, within four (4) Business Days of receipt of notice from
Caliper of the Disposition of all or some of such Covered Shares by Caliper, pay
to Caliper, by wire transfer of immediately available funds, an amount equal to
the positive difference, if any, between the Minimum Price multiplied by the
number of Covered Shares sold by Caliper, and the net amount actually received
by Caliper from such Disposition (after deduction of applicable brokerage
commissions and fees). The notice shall include the number of Covered Shares
sold and the net amount actually received by Caliper from the sale of the
shares.

                  (d) If for any reason (including, without limitation, because
the sale of the Covered Shares is restricted under the Securities Act or because
there is no liquid market for the Covered Shares) any Covered Shares included in
the Notice of Disposition and not repurchased by the Company pursuant to Section
7.2(b) remain unsold by Caliper thirty (30) days after the date of the Notice of
Disposition, Caliper shall so notify Company. Within four (4) Business Days of
receipt by Company of such notice, Company shall repurchase such unsold Covered
Shares by paying Caliper, by wire transfer of immediately available funds, an
amount equal to (i) the Fair Market Value on the day preceding the date of such
repurchase multiplied by the number of Covered Shares repurchased, plus (ii) the
positive difference, if any, between the Minimum Price and such Fair Market
Value multiplied by the number of Covered Shares repurchased. Within four (4)
Business Days of receipt of such amount from the Company, Caliper shall deliver
such repurchased Covered Shares to Company.

                  (e) Any amount paid by Company to Caliper under Section 7.2
(b)(ii), Section 7.2(c) or Section 7.2(d)(ii) shall be referred to as the
"Difference". The parties hereto


                                      14.
<PAGE>   15

agree that any payment of the Difference to Caliper shall constitute part of the
consideration for execution by Caliper of this Agreement.

                  (f) With respect to the sale of Covered Shares on any given
trading day, Caliper covenants and agrees to instruct the broker handling the
Disposition (the "BROKER") to sell, on any given trading day, a number of
Covered Shares that does not exceed the Threshold Number, calculated as of the
date of the Notice of Disposition.

                  (g) Notwithstanding anything in this Agreement to the
contrary, if at any time prior to February 21, 2003, the Company's shareholders
receive cash or securities in connection with a tender offer, recapitalization
transaction, merger or other business combination, then

                        (i) if 95% or more of the market value of the
consideration received by the Company's shareholders is cash, then the Company
shall, within four (4) Business Days of receipt of notice from Caliper of the
surrender by Caliper in such transaction of Covered Shares, pay to Caliper, by
wire transfer of immediately available funds, an amount equal to the positive
difference, if any, between the (x) Minimum Price multiplied by the number of
Covered Shares surrendered by Caliper in such transaction, and (y) the sum of
the net amount of cash plus the market value of any other consideration actually
received by Caliper in such transaction; and

                        (ii) if the consideration received by the Company's
shareholders is not all cash, then the securities received by Caliper in such
transaction shall be subject to the provisions of this Section 7 and shall be
substituted in lieu of the Common Stock in all portions of this Section 7 and
the Minimum Price shall be reduced by the amount of cash per share of Common
Stock received by Caliper, and after such reduction, the Minimum Price shall be
adjusted to give effect to such transaction.

            7.3 LIMITS ON COMPANY'S OBLIGATION TO PAY CALIPER.

                  (a) Notwithstanding anything to the contrary in Section 7.2,
if on any trading day during the Holding Period (other than a day when there is
no Registration Statement in effect with respect to the Registrable Shares
(including, without limitation, during a Suspension) or the Company's Common
Stock is not listed on an established stock exchange or a national market
system), the average of the Fair Market Value of the Common Stock as determined
pursuant to Section 7.1(c)(i) on each of the five (5) market trading days prior
to such date is equal to or greater than the Minimum Price, then for each
consecutive trading day following such date on which the Fair Market Value is
equal to or greater than the Minimum Price, if Caliper does not sell the
Threshold Number of Registrable Shares for such day, then the Company's
obligation to pay the Difference pursuant to Section 7.2 shall be deemed
satisfied with respect to a number of Registrable Shares equal to the Threshold
Number for such day less the number of Registrable Shares actually sold on such
day; provided, however that if, on any day upon which Caliper would otherwise be
required to sell shares pursuant to this Section 7.3(a), Caliper instructs the
Broker to sell the Threshold Number of Registrable Shares for such day at or
above the Minimum Price (net of applicable brokerage commissions) and the Broker
fails to sell all of such Threshold Number of Registrable Shares at a price at
or above the


                                      15.
<PAGE>   16

Minimum Price (net of applicable brokerage commissions and fees), the Company's
obligation to pay the Difference shall not be deemed satisfied with respect to
such number of Registrable Shares that the Broker was unable to sell at or above
the Minimum Price (net of applicable brokerage commissions and fees).

                  (b) If at the time of the sale by Caliper of any Registrable
Shares, there are any Uncovered Shares, then such sale of Registrable Shares
shall be deemed to be a sale of Covered Shares.

                  (c) EXAMPLES.

                        (i) Example 1. If the Fair Market Value of the Common
Stock during the Holding Period is at or above $36.11 per share for 12
consecutive trading days, and the daily Threshold Number for each of trading
days 6 through 12 is equal to 60,000, then, if Caliper sells no Registrable
Shares during days 6 through 12, the Company's obligation to repurchase the
Registrable Shares or to pay the Difference pursuant to Section 7.2 hereof shall
lapse and be deemed satisfied with respect to 360,000 Registrable Shares.
Assuming that Caliper sold no Registrable Shares during the Holding Period, at
the end of the Holding Period, Caliper would own 900,000 Registrable Shares, of
which 360,000 would be Uncovered Shares and 540,000 would be Covered Shares.

                        (ii) Example 2. If, in the case of Example 1 above,
Caliper further elects to sell 65,000 shares on Day 7, then under Section 7.3(a)
the Company's obligation to repurchase the Registrable Shares or to pay the
Difference pursuant to Section 7.2 hereof shall lapse and be deemed satisfied
with respect to 300,000 Registrable Shares. Assuming that Caliper sold no other
Registrable Shares during the Holding Period, at the end of the Holding Period,
Caliper would own 835,000 Registrable Shares, of which 300,000 would be
Uncovered Shares and 535,000 would be Covered Shares.

                        (iii) Example 3. If, in the case of Example 1 above,
Caliper further elects to sell 55,000 shares on Day 7, then under 7.3(a) the
Company's obligation to repurchase the Registrable Shares or to pay the
Difference pursuant to Section 7.2 hereof shall lapse and be deemed satisfied
with respect to 305,000 Registrable Shares. Assuming that Caliper sold no other
Registrable Shares during the Holding Period, at the end of the Holding Period,
Caliper would own 845,000 Registrable Shares, of which 305,000 would be
Uncovered Shares and 540,000 would be Covered Shares.

                        (iv) Example 4. If, in the case of Example 1 above,
Caliper further elects to sell 55,000 shares on Day 7, then under Section 7.3(a)
the Company's obligation to repurchase the Registrable Shares or to pay the
Difference pursuant to Section 7.2 hereof shall lapse and be deemed satisfied
with respect to 305,000 Registrable Shares. In addition, if the Fair Market
Value of the Common Stock was $35.00 on Day 13 and $37.00 on Day 14 and Caliper
elected to sell an additional 25,000 shares on Day 13, then at the end of the
Holding Period, Caliper would own 820,000 Registrable Shares, of which 305,000
would be Uncovered Shares and 515,000 would be Covered Shares.


                                      16.
<PAGE>   17

            7.4 Except as to the limitations set forth in Sections 7.2(f) and
7.3 hereof, the Company shall have no obligation to pay the Difference for any
Disposition of Registrable Shares occurring prior to August 21, 2002 or after
February 21, 2003.

      8. LETTER OF CREDIT AND OBLIGATION OF CALIPER TO DELIVER REDUCTION
CERTIFICATES. A letter of credit, in the form attached hereto as Exhibit C,
shall be provided by Deutsche Bank (the "BANK") for the benefit of Caliper,
effective as of the date hereof (the "LETTER OF CREDIT"). The stated amount of
the Letter of Credit shall initially be $32.5 million (the "STATED AMOUNT"). The
Stated Amount shall be subject to reduction in accordance with the subsections
of this Section 8.

            (a) TERM. The Letter of Credit will terminate upon the earlier of
(i) the date upon which, as a result of the submission to the Bank by Caliper of
a Draw Certificate or a Reduction Certificate pursuant to the Letter of Credit,
the Stated Amount of the Letter of Credit is reduced to zero; and (ii) August
26, 2003.

            (b) PAYMENT OF FEES FOR LETTER OF CREDIT AND RIGHT OF OFFSET. The
Company shall invoice Caliper on a quarterly basis for fifty percent (50%) of
all fees paid by the Company to Bank during such quarter pursuant to that
certain fee agreement between the Company and the Bank (the "FEE AGREEMENT");
provided that (i) Caliper shall pay one hundred percent (100%) of all fees
related to the Letter of Credit that accrue after the earlier to occur of (v)
five (5) Business days after the Disposition of all Covered Shares by Caliper in
a Disposition that does not require the Company to pay the Difference with
respect thereto; (w) five (5) Business Days after the payment by the Company of
the Difference in a Disposition that requires the Company to pay the Difference
with respect thereto; (x) five (5) Business Days after the repurchase of the
Registrable Shares and the payment of the Difference by the Company pursuant to
Section 7.2; (y) five (5) Business Days after the date that the Company's
obligations to pay the Difference has lapsed pursuant to Section 7.3 with
respect to all Registrable Shares; and (z) March 28, 2003; (ii) Caliper shall
pay one hundred percent (100%) of all fees attributable to the L/C Reduction
Amount (as defined below) with respect to each L/C Reduction (as defined below)
to the extent that such fees accrue after the L/C Reduction Date for such L/C
Reduction; and (iii) for purposes of this provision (x) an "L/C Reduction" means
any reduction in the Stated Amount of the Letter of Credit which would result
from the delivery by Caliper to the Bank of a Reduction Certificate pursuant to
Section 8(c)(i)(D) or Section 8(c)(i)(E); (y) "L/C Reduction Amount" means, for
any L/C Reduction, the amount of the reduction in the Stated Amount of the
Letter of Credit which results from the delivery by Caliper to the Bank of the
Reduction Certificate with respect to such L/C Reduction; and (z) "L/C Reduction
Date" means, for any L/C Reduction, the date five (5) Business Days after the
Company has made the payments referred in Section 8(c)(i)(D) or Section
8(c)(i)(E), as applicable, with respect to such L/C Reduction. All such invoices
shall be accompanied by a copy of the invoice submitted to the Company by the
Bank for such quarter. Caliper shall pay all properly invoiced fees within five
(5) Business Days of receipt of such invoice. The Company covenants and agrees
that it shall not modify the Fee Agreement without the prior written consent of
Caliper, which consent shall not be unreasonably withheld.


                                      17.
<PAGE>   18

            (c) COVENANTS OF CALIPER.

                  (i) Caliper covenants and agrees that:

                        (A) if Caliper sells Registrable Shares on or prior to
August 21, 2002, other than pursuant to Section 7.3(a), then within five (5)
Business Days of the day on which Caliper sells such Registrable Shares it shall
submit to the Bank a duly completed Early Sale Certificate (as defined in the
Letter of Credit) with respect to such sale;

                        (B) within five (5) Business Days of the day on which,
pursuant to Section 7.3(a), the Company's obligation to pay the Difference
pursuant to Section 7.2 is deemed satisfied as with respect to any Registrable
Shares, Caliper shall submit to the Bank a duly completed Reduced Obligation
Certificate (as defined in the Letter of Credit) with respect to such
Registrable Shares;

                        (C) if Caliper sells Registrable Shares after August 21,
2002 and receives a net amount greater than $36.11 per share sold, then within
five (5) Business Days of the day on which such sale occurs, Caliper shall
submit to the Bank, a duly completed Sale Certificate (as defined in the Letter
of Credit) with respect to such sale;

                        (D) if Caliper sells Registrable Shares after August 21,
2002 and receives a net amount less than $36.11 per share sold, then within one
hundred fifty-one (151) days of the day on which Caliper receives the payment
from the Company of the amount required to be paid by the Company to Caliper
pursuant to Section 7.2(c), Caliper shall submit to the Bank, a duly completed
Sale Certificate with respect to such sale and payment; and

                        (E) if the Company repurchases Registrable Shares
pursuant to Section 7.2(b), then within one hundred fifty-one (151) days of the
day on which Caliper receives the payment from the Company of the amount
required to be paid by the Company to Caliper pursuant to Section 7.2(b) or
7.2(d), as applicable, Caliper shall submit to the Bank, a duly completed
Repurchase Certificate (as defined in the Letter of Credit) with respect to such
repurchase.

                  (ii) If Caliper fails to submit any certificate which it is
required to submit pursuant to Section 8(c)(i), then Caliper shall pay all fees
that are incurred by the Company with respect to the Letter of Credit as a
result of such failure.

      9. NOTICES. All notices, requests, consents and other communications
hereunder shall be in writing, shall be mailed (i) if within domestic United
States by first-class registered or certified airmail, or nationally recognized
overnight express courier, postage prepaid, or by facsimile, or (ii) if
delivered from outside the United States, by International Federal Express or
facsimile, and shall be deemed given (A) if delivered by first-class registered
or certified mail domestic, three business days after so mailed, (B) if
delivered by nationally recognized overnight carrier, one business day after so
mailed, (C) if delivered by International Federal Express, two business days
after so mailed, and (D) if delivered by facsimile, upon electric confirmation
of receipt and shall be delivered as addressed as follows:


                                      18.
<PAGE>   19

                  (a) if to the Company, to:

                           ACLARA BioSciences, Inc.
                           1288 Pear Avenue
                           Mountain View, CA  94043-1432
                           Attn: President and CEO
                           Phone: (650) 210-1200
                           Telecopy: (650) 210-1210

                      with a copy to:

                           Latham & Watkins
                           135 Commonwealth Drive
                           Menlo Park, CA  94025
                           Attn: Michael W. Hall, Esq.
                           Phone: (650) 328-4600
                           Telecopy: (650) 463-2600

                  (b) if to Caliper, to the following address, or at such other
address or addresses as may have been furnished to the Company in writing:

                           Caliper Technologies Corp.
                           605 Fairchild Drive
                           Mountain View, California 94043-2234
                           Attn: Chief Accounting Officer
                           Phone: (650) 623-0700
                           Telecopy: (650) 623-0505

                      with a copies to:

                           Caliper Technologies Corp.
                           605 Fairchild Drive
                           Mountain View, California 94043-2234
                           Attn: Sr. Director of Legal Affairs
                           Phone: (650) 623-0700
                           Telecopy: (650) 623-0505

                      and

                           Covington & Burling
                           601 California Street
                           San Francisco, CA 94108
                           Attn: James C. Snipes
                           Phone: 415-591-6000
                           Telecopy: 415-591-6091

      10. CHANGES. This Agreement may not be modified or amended except pursuant
to an instrument in writing signed by the Company and Caliper.


                                      19.
<PAGE>   20

      11. HEADINGS. The headings of the various sections of this Agreement have
been inserted for convenience of reference only and shall not be deemed to be
part of this Agreement.

      12. GOVERNING LAW. This Agreement shall be governed by, and construed in
accordance with, the internal laws of the State of California, without giving
effect to the principles of conflicts of law.

      13. ENTIRE AGREEMENT. Except for the provisions contained in Section 20 of
the Settlement Agreement, this Agreement, together with the exhibits attached
hereto, constitutes the entire agreement between the parties hereto pertaining
to the subject matter hereof, and any and all other written or oral agreements
relating to such subject matter are expressly cancelled.

      14. COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall constitute an original, but all of which, when
taken together, shall constitute but one instrument, and shall become effective
when one or more counterparts have been signed by each party hereto and
delivered to the other parties.

      15. FINDER'S FEES. Each of the Company and Caliper represents that it
neither is nor will be obligated for any finder's fee or commission in
connection with this transaction.

      16. CALIFORNIA CORPORATE SECURITIES LAW. THE SALE OF THE SECURITIES WHICH
ARE THE SUBJECT OF THIS AGREEMENT HAS NOT BEEN QUALIFIED WITH THE COMMISSIONER
OF CORPORATIONS OF THE STATE OF CALIFORNIA AND THE ISSUANCE OF THE SECURITIES OR
THE PAYMENT OR RECEIPT OF ANY PART OF THE CONSIDERATION THEREFOR PRIOR TO THE
QUALIFICATION IS UNLAWFUL, UNLESS THE SALE OF SECURITIES IS EXEMPT FROM
QUALIFICATION BY SECTION 25100, 25102 OR 25105 OF THE CALIFORNIA CORPORATIONS
CODE. THE RIGHTS OF ALL PARTIES TO THIS AGREEMENT ARE EXPRESSLY CONDITIONED UPON
THE QUALIFICATION BEING OBTAINED, UNLESS THE SALE IS SO EXEMPT.

      17. DISPUTE RESOLUTION. All disputes, controversies, or claims of any
nature between or among the parties hereto arising our of, concerning or
relating to this Agreement shall be determined in accordance with Section 20 of
the Settlement Agreement.

      18. ASSIGNMENT. This Agreement, and any rights and obligations arising
hereunder, may not be sold, transferred, assigned, delegated, pledged, or
otherwise disposed of, in whole or part, whether voluntarily, by operation of
law or otherwise, by any party without the prior written consent of the other
party, which consent shall not be unreasonably withheld, except that either
party may assign this Agreement, without the other party's consent, in
connection with a Change in Control (as defined by the Cross-License Agreement
entered into by and between the Company and Caliper as of even date herewith) of
the assigning party. As a condition to any assignment or transfer under this
Section 18, the assignee or transferee shall assume all obligations of its
assignor or transferor under this Agreement. The rights and liabilities of the
parties hereto will bind, and inure to the benefit of, their respective and
permitted assignees and successors. Any attempted assignment or transfer other
than in accordance with this Section 18 shall be null and void.

                            [SIGNATURE PAGE FOLLOWS]


                                      20.
<PAGE>   21

      IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
executed and delivered as of the day and year first written above.

ACLARA BIOSCIENCES, INC.                   CALIPER TECHNOLOGIES CORPORATION
a Delaware corporation                     a Delaware corporation

/s/ Joseph M. Limber                       /s/ James L. Knighton
-------------------------------------      -------------------------------------
Joseph M. Limber                           James L. Knighton
President and Chief Executive Officer      Chief Financial Officer























                                [SIGNATURE PAGE]

<PAGE>   22

                                    EXHIBIT A

                         CERTIFICATE OF SUBSEQUENT SALE

Mellon Investor Services LLC
85 Challenger Road
Ridgefield Park, NJ  07660
Attention:  Restricted Transfer Department, Phyllis Del Vecchio
Facsimile: (201) 296-4206

      RE:   Sale of Shares of Common Stock of ACLARA BioSciences, Inc. (the
            "Company") pursuant to the Company's Prospectus dated
                             (the "Prospectus")
            ----------------

Ladies and Gentlemen:

      The undersigned hereby certifies, in connection with the sale of shares of
Common Stock of the Company included in the table of Selling Stockholders in the
Prospectus, that the undersigned has sold the shares pursuant to the Prospectus
and in a manner described under the caption "Plan of Distribution" in the
Prospectus and in accordance with the Prospectus delivery requirements of the
Securities Act of 1933, as amended.


Selling Stockholder (the beneficial owner):
                                            ------------------------------------
Record Holder (e.g., if held in name of nominee):
                                                  ------------------------------
Restricted Stock Certificate No.(s):
                                     -------------------------------------------
Number of Shares Sold:
                       ---------------------------------------------------------
Date of Sale:
              ------------------------------------------------------------------

      In the event that you receive a stock certificate(s) representing more
shares of Common Stock than have been sold by the undersigned, then you should
return to the undersigned a newly issued certificate for such excess shares in
the name of the Record Holder and BEARING A RESTRICTIVE LEGEND. Further, you
should place a stop transfer on your records with regard to such certificate.

                                         Very truly yours,

Dated:                                   By:
       -----------------------------        ------------------------------------

                                         Print Name:

                                         Title:
                                               ---------------------------------

cc:  President and CEO
     ACLARA BioSciences, Inc.
     1288 Pear Avenue
     Mountain View, CA  94043-1432


<PAGE>   23

                                    EXHIBIT B

                          LETTER FROM LATHAM & WATKINS


Caliper Technologies Corp.
650 Fairchild Drive
Mountain View, California 94043-2234

Ladies and Gentlemen:

      We have acted as special counsel to ACLARA BioSciences, Inc.., a Delaware
corporation (the "Company"), in connection with the issuance of 900,000 shares
of the Company's common stock, par value $.001 per share (the "Shares"),
pursuant to the Common Stock Issuance Agreement by and between the Company and
Caliper Technologies Corp, a Delaware corporation, dated as of March ___, 2001
(the "Agreement"). Capitalized terms used herein and not otherwise defined
herein shall have the meanings given to them in the Agreement.

      As such counsel, we have examined such matters of fact and questions of
law as we have considered appropriate for purposes of this opinion. In our
examination, we have assumed the genuineness of all signatures (other than those
on behalf of the Company), the authenticity of all documents submitted to us as
originals, and the conformity to authentic original documents of all documents
submitted to us as copies. As to facts material to the opinions, statements and
assumptions expressed herein, we have, with your consent, relied upon oral or
written statements and representations of officers and other representatives of
the Company and others. In addition, we have obtained and relied upon such
certificates and assurances from public officials as we have deemed necessary.

      We are opining herein as to the effect on the subject transaction only of
the federal laws of the United States and the General Corporation Law of the
State of Delaware, and we express no opinion with respect to the applicability
thereto, or the effect thereon, of the laws of any other jurisdiction or, in the
case of Delaware, any other laws, or as to any matters of municipal law or the
laws of any local agencies within any state.

      Subject to the foregoing, it is our opinion, as of the date hereof, that
the Shares, upon issuance, delivery and payment therefor in the manner
contemplated by the Agreement, will be validly issued, fully paid and
nonassessable.

      This opinion is rendered only to you and is solely for your benefit in
connection with the transactions covered hereby. This opinion may not be relied
upon by you for any other purpose, without our prior written consent.

                                     Very truly yours,


<PAGE>   24



                                    EXHIBIT C

                            FORM OF LETTER OF CREDIT