EXHIBIT 99.3

                            FORM OF RIGHT CERTIFICATE

CERTIFICATE NO. R-                                                  _____ RIGHTS

        NOT EXERCISABLE AFTER NOVEMBER 16, 2011 OR EARLIER IF REDEMPTION OR
        EXCHANGE OCCURS. THE RIGHTS ARE SUBJECT TO REDEMPTION AT $.001 PER RIGHT
        AND TO EXCHANGE ON THE TERMS SET FORTH IN THE RIGHTS AGREEMENT.

                                RIGHT CERTIFICATE

                          MOLECULAR DEVICES CORPORATION

        This certifies that ___________________ or registered assigns, is the
registered owner of the number of Rights set forth above, each of which entitles
the owner thereof, subject to the terms, provisions and conditions of the Rights
Agreement, dated as of October 25, 2001 (the "Rights Agreement"), between
MOLECULAR DEVICES CORPORATION, a Delaware corporation (the "Company"), and
EQUISERVE TRUST COMPANY, N.A. (the "Rights Agent"), to purchase from the Company
at any time after the Distribution Date (as such term is defined in the Rights
Agreement) and prior to 5:00 p.m., Pacific Time, on November 16, 2011 at the
office of the Rights Agent designated for such purpose, or at the office of its
successor as Rights Agent, one one-hundredth of a fully paid non-assessable
share of Series A Junior Participating Preferred Stock, par value $.001 per
share (the "Preferred Shares"), of the Company, at a purchase price of $110 per
one one-hundredth of a Preferred Share (the "Purchase Price"), upon presentation
and surrender of this Right Certificate with the Form of Election to Purchase
duly executed. The number of Rights evidenced by this Right Certificate (and the
number of one one-hundredths of a Preferred Share which may be purchased upon
exercise hereof) set forth above, and the Purchase Price set forth above, are
the number and Purchase Price as of November 16, 2001, based on the Preferred
Shares as constituted at such date.

        From and after the time any Person becomes an Acquiring Person, (as such
terms are defined in the Rights Agreement), if the Rights evidenced by this
Right Certificate are beneficially owned by (i) an Acquiring Person or an
Affiliate or Associate of any such Acquiring Person (as such terms are defined
in the Rights Agreement), (ii) a transferee of any such Acquiring Person,
Associate or Affiliate who becomes a transferee after the Acquiring Person
becomes such, or (iii) under certain circumstances specified in the Rights
Agreement, a transferee of any such Acquiring Person, Associate or Affiliate who
becomes a transferee prior to or concurrently with the Acquiring Person becoming
such, such Rights shall become null and void without any further action and no
holder hereof shall have any right with respect to such Rights from and after
the time any Person becomes an Acquiring Person.

        As provided in the Rights Agreement, the Purchase Price and the number
of one one-hundredths of a Preferred Share which may be purchased upon the
exercise of the Rights



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evidenced by this Right Certificate are subject to modification and adjustment
upon the happening of certain events.

        This Right Certificate is subject to all of the terms, provisions and
conditions of the Rights Agreement, as amended from time to time, which terms,
provisions and conditions are hereby incorporated herein by reference and made a
part hereof and to which Rights Agreement reference is hereby made for a full
description of the rights, limitations of rights, obligations, duties and
immunities hereunder of the Rights Agent, the Company and the holders of the
Right Certificates. Copies of the Rights Agreement are on file at the principal
executive offices of the Company and the above-mentioned offices of the Rights
Agent.

        This Right Certificate, with or without other Right Certificates, upon
surrender at the office of the Rights Agent designated for such purpose, may be
exchanged for another Right Certificate or Right Certificates of like tenor and
date evidencing Rights entitling the holder to purchase a like aggregate number
of Preferred Shares as the Rights evidenced by the Right Certificate or Right
Certificates surrendered shall have entitled such holder to purchase. If this
Right Certificate shall be exercised in part, the holder shall be entitled to
receive upon surrender hereof another Right Certificate or Right Certificates
for the number of whole Rights not exercised.

        Subject to the provisions of the Rights Agreement, the Rights evidenced
by this Certificate (i) may be redeemed by the Company at a redemption price of
$.001 per Right or (ii) may be exchanged in whole or in part for shares of the
Company's Common Stock, par value $.001 per share, or, upon circumstances set
forth in the Rights Agreement, cash, property or other securities of the
Company, including fractions of a share of Preferred Stock.

        No fractional Preferred Shares will be issued upon the exercise of any
Right or Rights evidenced hereby (other than fractions which are integral
multiples of one one-hundredth of a Preferred Share, which may, at the election
of the Company, be evidenced by depositary receipts) but in lieu thereof a cash
payment will be made, as provided in the Rights Agreement.

        No holder of this Right Certificate shall be entitled to vote or receive
dividends or be deemed for any purpose the holder of the Preferred Shares or of
any other securities of the Company which may at any time be issuable on the
exercise hereof, nor shall anything contained in the Rights Agreement or herein
be construed to confer upon the holder hereof, as such, any of the rights of a
stockholder of the Company or any right to vote for the election of directors or
upon any matter submitted to stockholders at any meeting thereof, or to give or
withhold consent to any corporate action, or to receive notice of meetings or
other actions affecting stockholders (except as provided in the Rights
Agreement), or to receive dividends or subscription rights, or otherwise, until
the Right or Rights evidenced by this Right Certificate shall have been
exercised as provided in the Rights Agreement.

        This Right Certificate shall not be valid or obligatory for any purpose
until it shall have been countersigned by the Rights Agent.



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        WITNESS the facsimile signature of the proper officers of the Company
and its corporate seal. Dated as of __________ ___, _____.



ATTEST:                               MOLECULAR DEVICES CORPORATION

---------------------------------     ------------------------------------------
James C. Kitch                        Timothy A. Harkness
Secretary                             Vice President and Chief Financial Officer

COUNTERSIGNED:

EQUISERVE TRUST COMPANY, N.A.

as Rights Agent

By:
   ------------------------------
   [AUTHORIZED SIGNATURE]



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                    FORM OF REVERSE SIDE OF RIGHT CERTIFICATE

                               FORM OF ASSIGNMENT

             (TO BE EXECUTED BY THE REGISTERED HOLDER IF SUCH HOLDER
                   DESIRES TO TRANSFER THE RIGHT CERTIFICATE.)

        FOR VALUE RECEIVED ______________________________________ hereby sells,
assigns and transfers unto


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                  (Please print name and address of transferee)

_____________________________________________________________________ this Right
Certificate, together with all right, title and interest therein, and does
hereby irrevocably constitute and appoint ________________________ Attorney, to
transfer the within Right Certificate on the books of the within-named Company,
with full power of substitution.

Dated:
       ---------------------


                                            ------------------------------------
                                            Signature



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SIGNATURE GUARANTEED:

        Signatures must be guaranteed by an "eligible guarantor institution" as
defined in Rule 17Ad-15 promulgated under the Securities Exchange Act of 1934,
as amended.

                    ----------------------------------------

        The undersigned hereby certifies that (1) the Rights evidenced by this
Right Certificate are not being sold, assigned or transferred by or on behalf of
a Person who is or was an Acquiring Person, an Interested Stockholder or an
Affiliate or Associate thereof (as such terms are defined in the Rights
Agreement); and (2) after due inquiry and to the best of the knowledge of the
undersigned, the undersigned did not acquire the Rights evidenced by this Right
Certificate from any Person who is or was an Acquiring Person, an Interested
Stockholder, or an Affiliate or Associate thereof.


                                            ------------------------------------
                                            Signature



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                          FORM OF ELECTION TO PURCHASE

              (TO BE EXECUTED IF HOLDER DESIRES TO EXERCISE RIGHTS
                     REPRESENTED BY THE RIGHT CERTIFICATE.)

To EQUISERVE TRUST COMPANY, N.A.:

        The undersigned hereby irrevocably elects to exercise
___________________________ Rights represented by this Right Certificate to
purchase the Preferred Shares issuable upon the exercise of such Rights and
requests that certificates for such Preferred Shares be issued in the name of:

Please insert social security
or other identifying number:
                             --------------


--------------------------------------------------------------------------------
                         (Please print name and address)

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If such number of Rights shall not be all the Rights evidenced by this Right
Certificate, a new Right Certificate for the balance remaining of such Rights
shall be registered in the name of and delivered to:

Please insert social security
or other identifying number:
                             --------------

--------------------------------------------------------------------------------
                         (Please print name and address)

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Dated:
       ---------------------


                                            ------------------------------------
                                            Signature



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SIGNATURE GUARANTEED:

        Signatures must be guaranteed by an "eligible guarantor institution" as
defined in Rule 17Ad-15 promulgated under the Securities Exchange Act of 1934,
as amended.

                    ----------------------------------------

        The undersigned hereby certifies that (1) the Rights evidenced by this
Right Certificate are not beneficially owned by nor are they being exercised on
behalf of an Acquiring Person, an Interested Stockholder or an Affiliate or
Associate thereof (as such terms are defined in the Rights Agreement); and (2)
after due inquiry and to the best of the knowledge of the undersigned, the
undersigned did not acquire the Rights evidenced by this Right Certificate from
any Person who is or was an Acquiring Person, an Interested Stockholder, or an
Affiliate or Associate thereof.


                                            ------------------------------------
                                            Signature

                    ----------------------------------------

                                     NOTICE

        The signature in the Form of Assignment or Form of Election to Purchase,
as the case may be, must conform to the name as written upon the face of this
Right Certificate in every particular, without alteration or enlargement or any
change whatsoever.

        In the event the certification set forth above in the Form of Assignment
or the Form of Election to Purchase, as the case may be, is not completed, the
Company and the Rights Agent will deem the beneficial owner of the Rights
evidenced by this Right Certificate to be an Acquiring Person or an Affiliate or
Associate thereof (as defined in the Rights Agreement) and such Assignment or
Election to Purchase will not be honored.



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