Document:

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                                                                     EXHIBIT 4.1

                                                               EXECUTION VERSION

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                                RIGHTS AGREEMENT

                                     BETWEEN

                          ALNYLAM PHARMACEUTICALS, INC.

                                       AND

                         EQUISERVE TRUST COMPANY, N.A.,

                                 AS RIGHTS AGENT

                            DATED AS OF JULY 13, 2005

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                                Table of Contents

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<S>                                                                                              <C>
Section 1.   Certain Definitions.............................................................     1

Section 2.   Appointment of Rights Agent.....................................................     6

Section 3.   Issuance of Rights..............................................................     6

Section 4.   Form of Rights Certificates.....................................................     8

Section 5.   Countersignature and Registration...............................................     9

Section 6.   Transfer, Split Up, Combination and Exchange of Rights Certificates;
             Mutilated, Destroyed, Lost or Stolen Rights Certificates........................     9

Section 7.   Exercise of Rights; Purchase Price; Expiration Date of Rights...................    10

Section 8.   Cancellation and Destruction of Rights Certificates.............................    12

Section 9.   Reservation and Availability of Capital Stock...................................    12

Section 10.  Preferred Stock Record Date.....................................................    14

Section 11.  Adjustment of Purchase Price, Number and Kind of Shares or Number of Rights.....    14

Section 12.  Certificate of Adjusted Purchase Price or Number of Shares......................    21

Section 13.  Consolidation, Merger or Sale or Transfer of Assets or Earning Power............    22

Section 14.  Fractional Rights and Fractional Shares.........................................    24

Section 15.  Rights of Action................................................................    25

Section 16.  Agreement of Rights Holders.....................................................    26

Section 17.  Rights Certificate Holder Not Deemed a Stockholder..............................    26

Section 18.  Concerning the Rights Agent.....................................................    27

Section 19.  Merger or Consolidation or Change of Name of Rights Agent.......................    27

Section 20.  Duties of Rights Agent..........................................................    28

Section 21.  Change of Rights Agent..........................................................    30

Section 22.  Issuance of New Rights Certificates.............................................    30

Section 23.  Redemption; Independent Director Review.........................................    31
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<S>                                                                                               <C>
Section 24.  Exchange........................................................................     32

Section 25.  Notice of Certain Events........................................................     33

Section 26.  Notices.........................................................................     34

Section 27.  Supplements and Amendments......................................................     35

Section 28.  Successors......................................................................     35

Section 29.  Actions by the Board, etc.......................................................     35

Section 30.  Benefits of this Agreement......................................................     35

Section 31.  Severability....................................................................     35

Section 32.  Governing Law...................................................................     36

Section 33.  Counterparts....................................................................     36

Section 34.  Descriptive Headings............................................................     36

Section 35.  Force Majeure...................................................................     36
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                                RIGHTS AGREEMENT

RIGHTS AGREEMENT, dated as of July 13, 2005 (the "Agreement"), between Alnylam
Pharmaceuticals, Inc., a Delaware corporation (the "Company"), and EquiServe
Trust Company, N.A., a national banking association, as Rights Agent (the
"Rights Agent").

                               W I T N E S S E T H

WHEREAS, on July 13, 2005 the Board of Directors of the Company (the "Board")
authorized and declared a dividend distribution of one Right for each share of
Common Stock (as hereinafter defined) of the Company outstanding at the close of
business on July 26, 2005 (the "Record Date"), and authorized the issuance of
one Right (as such number may hereinafter be adjusted pursuant to the provisions
of Section 11(i) or Section 11(p) hereof) for each share of Common Stock of the
Company issued between the Record Date (whether originally issued or delivered
from the Company's treasury) and the earlier of the Distribution Date or the
Expiration Date, each Right initially representing the right to purchase one
one-thousandth of a share of Series A Junior Participating Preferred Stock of
the Company having the rights, powers and preferences set forth in the form of
Certificate of Designations attached hereto as Exhibit A, upon the terms and
subject to the conditions hereinafter set forth (the "Rights");

NOW, THEREFORE, in consideration of the premises and the mutual agreements
herein set forth, the parties hereby agree as follows:

      Section 1. Certain Definitions. For purposes of this Agreement, the
following terms have the meanings indicated:

      (a) "Acquiring Person" shall mean any Person who or which, together with
all Affiliates and Associates of such Person, shall be the Beneficial Owner of
20% or more of the shares of Common Stock then outstanding, but shall not
include (i) the Company, (ii) any Subsidiary of the Company, (iii) any employee
benefit plan of the Company or of any Subsidiary of the Company or (iv) any
Person organized, appointed or established by the Company for or pursuant to the
terms of any such plan. Notwithstanding the foregoing, (x) no Person shall
become an "Acquiring Person" as the result of an acquisition of Common Stock by
the Company which, by reducing the number of shares outstanding, increases the
proportionate number of shares beneficially owned by such Person to 20% or more
of the shares of Common Stock of the Company then outstanding; provided, however
that if a Person shall become the Beneficial Owner of 20% or more of the shares
of Common Stock of the Company then outstanding as the result of an acquisition
of Common Stock by the Company and shall, following written notice from, or
public disclosure by the Company of such share purchases by the Company become
the Beneficial Owner of any additional Common Stock of the Company and shall
then beneficially own 20% or more of the shares of Common Stock then
outstanding, then such Person shall be deemed to be an "Acquiring Person" and
(y) if the Board determines in good faith that a Person who would otherwise be
an "Acquiring Person," as defined pursuant to the foregoing provisions

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of this paragraph (a), has become such inadvertently, and such Person divests as
promptly as practicable (as determined in good faith by the Board of Directors),
but in any event within 15 Business Days, following receipt of written notice
from the Company of such event, of Beneficial Ownership of a sufficient number
of shares of Common Stock so that such Person would no longer be an "Acquiring
Person," as defined pursuant to the foregoing provisions of this paragraph (a),
then such Person shall not be deemed to be an "Acquiring Person" for any
purposes of this Agreement unless and until such Person shall again become an
"Acquiring Person."

      (b) "Act" shall mean the Securities Act of 1933, as amended.

      (c) "Affiliate" and "Associate" shall have the respective meanings
ascribed to such terms in Rule 12b-2 of the General Rules and Regulations under
the Securities Exchange Act of 1934, as amended (the "Exchange Act") as in
effect on the date of this Agreement.

      (d) "Adjustment Shares" shall have the meaning set forth in Section
11(a)(ii).

      (e) A Person shall be deemed the "Beneficial Owner" of, and shall be
deemed to "beneficially own," any securities:

            (i) which such Person or any of such Person's Affiliates or
Associates, directly or indirectly, owns or has the right to acquire (whether
such right is exercisable immediately or only after the passage of time)
pursuant to any agreement, arrangement or understanding (other than customary
agreements with and between underwriters and selling group members with respect
to a bona fide public offering of securities or agreements with or between
Persons and the Company with respect to any other bona fide issuance of
securities by the Company to such Persons for resale within 40 days, including
without limitation pursuant to Section 4(2) of the Act or Rule 144A or
Regulation S promulgated under the Act), whether or not in writing, or upon the
exercise of conversion rights, exchange rights, other rights, warrants or
options, or otherwise; provided, however, that a Person shall not be deemed the
"Beneficial Owner" of, or to "beneficially own," (A) securities tendered
pursuant to a tender or exchange offer made by or on behalf of such Person or
any of such Person's Affiliates or Associates until such tendered securities are
accepted for purchase or exchange, or (B) securities issuable upon exercise of
Rights at any time prior to the occurrence of a Triggering Event, or (C)
securities issuable upon exercise of Rights from and after the occurrence of a
Triggering Event which Rights were acquired by such Person or any of such
Person's Affiliates or Associates prior to the Distribution Date or pursuant to
Section 3(a) or Section 22 hereof (the "Original Rights") or pursuant to Section
11(i) hereof in connection with an adjustment made with respect to any Original
Rights;

            (ii) which such Person or any of such Person's Affiliates or
Associates, directly or indirectly, has the right to vote or dispose of or has
"beneficial ownership" of (as determined pursuant to Rule 13d-3 of the General
Rules and Regulations under the Exchange Act, or any comparable or successor
rule), including pursuant to any agreement, arrangement or understanding (other
than customary agreements with and between underwriters and selling group
members with respect to a bona fide public offering of securities or agreements
with or

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between Persons and the Company with respect to any other bona fide issuance of
securities by the Company to such Persons for resale within 40 days, including
without limitation pursuant to Section 4(2) of the Act or Rule 144A or
Regulation S promulgated under the Act), whether or not in writing; provided,
however, that a Person shall not be deemed the "Beneficial Owner" of, or to
"beneficially own," any security under this subparagraph (ii) as a result of an
agreement, arrangement or understanding to vote such security if such agreement,
arrangement or understanding: (A) arises solely from a revocable proxy or
consent given in response to a public proxy or consent solicitation made
pursuant to, and in accordance with, the applicable provisions of the General
Rules and Regulations under the Exchange Act, and (B) is not then reportable by
such Person on Schedule 13D under the Exchange Act (or any comparable or
successor report); or

            (iii) which are beneficially owned, directly or indirectly, by any
other Person (or any Affiliate or Associate thereof) with which such Person (or
any of such Person's Affiliates or Associates) has any agreement, arrangement or
understanding (other than customary agreements with and between underwriters and
selling group members with respect to a bona fide public offering of securities
or agreements with or between Persons and the Company with respect to any other
bona fide issuance of securities by the Company to such Persons for resale
within 40 days, including without limitation pursuant to Section 4(2) of the Act
or Rule 144A or Regulation S promulgated under the Act) whether or not in
writing, for the purpose of acquiring, holding, voting (except pursuant to a
revocable proxy or consent as described in the proviso to subparagraph (ii) of
this paragraph (e)) or disposing of any voting securities of the Company.

For all purposes of this Agreement, any calculation of the number of shares of
Common Stock outstanding at any particular time, including for purposes of
determining the particular percentage of such outstanding shares of Common Stock
of which any Person is the Beneficial Owner, shall be made in accordance with
the last sentence of Rule 13d-3(d)(l)(i) of the General Rules and Regulations
under the Exchange Act.

      (f) "Board" shall have the meaning set forth in the WHEREAS clause at the
beginning of this Agreement.

      (g) "Business Day" shall mean any day other than a Saturday, Sunday or a
day on which banking institutions in the Commonwealth of Massachusetts are
authorized or obligated by law or executive order to close.

      (h) "Close of business" on any given date shall mean 5:00 p.m., Boston
time, on such date; provided, however, that if such date is not a Business Day
it shall mean 5:00 p.m., Boston time, on the next succeeding Business Day.

      (i) "Common Stock" shall mean the common stock, $.01 par value, of the
Company, except that "Common Stock" when used with reference to any Person other
than the Company shall mean the capital stock of such Person with the greatest
voting power, or the equity securities or other equity interest having power to
control or direct the management, of such Person.

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      (j) "Common stock equivalents" shall have the meaning set forth in Section
11(a)(iii) hereof.

      (k) "Company" shall have the meaning set forth in the introductory
paragraph hereof.

      (l) "Current market price" shall have the meaning set forth in Section
11(d)(i) hereof.

      (m) "Current Value" shall have the meaning set forth in Section 11(a)(iii)
hereof.

      (n) "Distribution Date" shall have the meaning set forth in Section 3(a)
hereof.

      (o) "Equivalent Preferred Stock" shall have the meaning set forth in
Section 11(b) hereof.

      (p) "Exchange Act" shall have the meaning set forth in Section 1(c)
hereof.

      (q) "Exchange Ratio" shall have the meaning set forth in Section 24(a)
hereof.

      (r) "Expiration Date" shall have the meaning set forth in Section 7(a)
hereof.

      (s) "Final Expiration Date" shall mean the close of business on July 13,
2015.

      (t) "Permitted Offer" shall mean a tender offer or an exchange offer for
all outstanding shares of Common Stock at a price and on terms determined, prior
to the consummation of such tender offer or exchange offer, by directors
constituting at least 75% of all of the members of the Board, after receiving
advice from a nationally recognized investment banking firm selected by the
Board, to be (a) at a price that is fair to stockholders (taking into account
all factors which such members of the Board deem relevant including, without
limitation, prices which could reasonably be achieved if the Company or its
assets were sold on an orderly basis designed to realize maximum value) and (b)
otherwise in the best interests of the Company and its stockholders.

      (u) "Person" shall mean any individual, firm, corporation, partnership,
trust, association, limited liability company or other entity.

      (v) "Preferred Stock" shall mean shares of Series A Junior Participating
Preferred Stock, $.01 par value, of the Company having the rights and
preferences set forth in the form of Certificate of Designations attached to
this Agreement as Exhibit A and, to the extent that there is not a sufficient
number of shares of Series A Junior Participating Preferred Stock authorized to
permit the full exercise of the Rights, any other series of Preferred Stock,
$.01 par value, of the Company designated for such purpose containing terms
substantially similar to the terms of the Series A Junior Participating
Preferred Stock.

      (w) "Principal Party" shall have the meaning set forth in Section 13(b)
hereof.

      (x) "Purchase Price" shall have the meaning set forth in Section 4(a)
hereof.

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      (y) "Record Date" shall have the meaning set forth in the WHEREAS clause
at the beginning of this Agreement.

      (z) "Redemption Date" shall have the meaning set forth in Section 7(a)
hereof.

      (aa) "Redemption Price" shall have the meaning set forth in Section 23(a)
hereof.

      (bb) "Rights" shall have the meaning set forth in the WHEREAS clause at
the beginning of this Agreement.

      (cc) "Rights Agent" shall have the meaning set forth in the introductory
paragraph hereof.

      (dd) "Rights Certificates" shall have the meaning set forth in Section
3(a) hereof.

      (ee) "Section 11(a)(ii) Event" shall mean an acquisition of Common Stock
described in the first sentence of Section 11(a)(ii) hereof.

      (ff) "Section 11(a)(ii) Trigger Date" shall have the meaning set forth in
Section 11(a)(iii) hereof.

      (gg) "Section 13 Event" shall mean any event described in clauses (x), (y)
or (z) of Section 13(a) hereof.

      (hh) "Spread" shall have the meaning set forth in Section 11(a)(iii)
hereof.

      (ii) "Stock Acquisition Date" shall mean the later of (i) the first date
of public announcement (which, for purposes of this definition, shall include,
without limitation, a report filed pursuant to Section 13(d) under the Exchange
Act) by the Company or an Acquiring Person that an Acquiring Person has become
such or (ii) the first date on which an executive officer of the Company has
actual knowledge that an Acquiring Person has become such; provided, however
that, if such Person is deemed not to be an Acquiring Person pursuant to clause
(y) of Section 1(a) hereof, no Stock Acquisition Date shall be deemed to have
occurred.

      (jj) "Subsidiary" shall mean, with reference to any Person, any
corporation or other entity of which an amount of voting securities sufficient
to elect at least a majority of the directors (or comparable body) of such
corporation or other entity is beneficially owned, directly or indirectly, by
such Person, or otherwise controlled by such Person.

      (kk) "Substitution Period" shall have the meaning set forth in Section
11(a)(iii) hereof.

      (ll) "Trading Day" shall have the meaning set forth in Section 11(d)(i)
hereof.

      (mm) "Triggering Event" shall mean any Section 11(a)(ii) Event or any
Section 13 Event.

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      Section 2. Appointment of Rights Agent. The Company hereby appoints
the Rights Agent to act as agent for the Company and the holders of the Rights
(who, in accordance with Section 3 hereof, shall prior to the Distribution Date
also be the holders of the Common Stock) in accordance with the terms and
conditions hereof, and the Rights Agent hereby accepts such appointment. The
Company may from time to time appoint such Co-Rights Agents as it may deem
necessary or desirable upon ten (10) days' prior written notice to the Rights
Agent. The Rights Agent shall have no duty to supervise, and shall in no event
be liable for, the acts or omissions of any such Co-Rights Agent.

      Section 3. Issuance of Rights.

      (a) Until the earlier of (i) the close of business on the tenth Business
Day (or such later date as may be determined by the Board) after the Stock
Acquisition Date (or, if the tenth Business Day after the Stock Acquisition Date
occurs before the Record Date, the close of business on the Record Date), or
(ii) the close of business on the tenth Business Day (or such later date as may
be determined by action of the Board) after the date that a tender or exchange
offer (other than a Permitted Offer) by any Person (other than the Company, any
Subsidiary of the Company, any employee benefit plan of the Company or of any
Subsidiary of the Company, or any Person organized, appointed or established by
the Company for or pursuant to the terms of any such plan) is first published or
sent or given within the meaning of Rule 14d-2 of the General Rules and
Regulations under the Exchange Act, if upon consummation thereof, such Person
would be the Beneficial Owner of 20% or more of the shares of Common Stock then
outstanding, (the earlier of (i) and (ii) being herein referred to as the
"Distribution Date"), (x) the Rights will be evidenced by the certificates for
the Common Stock registered in the names of the holders of the Common Stock
(which certificates for Common Stock shall be deemed also to be certificates for
Rights) and not by separate certificates, and (y) the Rights will be
transferable only in connection with the transfer of the underlying shares of
Common Stock (including a transfer to the Company). As soon as practicable after
the Distribution Date, the Rights Agent will send by first-class, insured,
postage prepaid mail, to each record holder of the Common Stock as of the close
of business on the Distribution Date, at the address of such holder shown on the
records of the Company, one or more rights certificates, in substantially the
form of Exhibit B hereto (the "Rights Certificates"), evidencing one Right for
each share of Common Stock so held, subject to adjustment as provided herein.
With respect to certificates for the Common Stock outstanding as of the close of
business on the Record Date, until the Distribution Date, the Rights will be
evidenced by such certificates for the Common Stock and the registered holders
of the Common Stock shall also be the registered holders of the associated
Rights. In addition, in connection with the issuance or sale of shares of Common
Stock following the Distribution Date and prior to the redemption or expiration
of the Rights, the Company (i) shall, with respect to shares of Common Stock so
issued or sold pursuant to the exercise of stock options or under any employee
benefit plan or arrangement, or upon the exercise, conversion or exchange of
securities granted or issued by the Company prior to the Distribution Date, and
(ii) may, in any other case, if deemed necessary or appropriate by the Board,
issue Rights Certificates representing the appropriate number of Rights in
connection with such issuance or sale; provided, however, that (x) no such
Rights Certificate shall be issued if, and to the extent that, the Company shall
be advised by counsel that such issuance would create a significant risk of
material adverse tax consequences to the Company or the Person to whom such
Rights

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Certificate would be issued, and (y) no such Rights Certificate shall be issued
if, and to the extent that, appropriate adjustment shall otherwise have been
made in lieu of the issuance thereof. In the event that an adjustment in the
number of Rights per share of Common Stock has been made pursuant to Sections
11(i) or 11(p) hereof, at the time of distribution of the Rights Certificates,
the Company shall make the necessary and appropriate rounding adjustments (in
accordance with Section 14(a) hereof) so that Rights Certificates representing
only whole numbers of Rights are distributed and cash is paid in lieu of any
fractional Rights. As of and after the Distribution Date, the Rights will be
evidenced solely by such Rights Certificates.

      (b) As promptly as practicable following the Record Date, the Company will
send a copy of a Summary of Rights to Purchase Preferred Stock, in substantially
the form attached hereto as Exhibit C, by first-class, postage prepaid mail, to
each record holder of the Common Stock as of the close of business on the Record
Date, at the address of such holder shown on the records of the Company. The
failure to send a copy of the Summary of Rights shall not affect the
enforceability of any part of this Rights Agreement or the rights of any holder
of the Rights.

      (c) Rights shall be issued (i) in respect of all shares of Common Stock
that are issued (either as an original issuance or from the Company's treasury)
after the Record Date but prior to the earlier of the Distribution Date or the
Expiration Date and (ii) in connection with the issuance or sale of shares of
Common Stock following the Distribution Date and prior to the redemption or
expiration of the Rights (x) with respect to shares of Common Stock so issued or
sold pursuant to the exercise of stock options or under any employee benefit
plan or arrangement, or upon the exercise, conversion or exchange of securities,
granted or issued by the Company prior to the Distribution Date and (y) with
respect to shares of Common Stock so issued or sold in any other case, if deemed
necessary or appropriate by the Board. Certificates representing such shares of
Common Stock (including, without limitation, certificates issued upon transfer
or exchange of Common Stock) shall also be deemed to be certificates for Rights,
and shall bear the following legend:

            This certificate also evidences and entitles the holder hereof to
            certain Rights as set forth in the Rights Agreement between Alnylam
            Pharmaceuticals, Inc. ( the "Company") and EquiServe Trust Company,
            N.A. (the "Rights Agent") dated as of July 13, 2005, as the same may
            be amended, restated or renewed from time to time (the "Rights
            Agreement"), the terms of which are hereby incorporated herein by
            reference and a copy of which is on file at the principal offices of
            the Company. Under certain circumstances, as set forth in the Rights
            Agreement, such Rights will be evidenced by separate certificates
            and will no longer be evidenced by this certificate. The Company
            will mail to the holder of this certificate a copy of the Rights
            Agreement, as in effect on the date of mailing, without charge
            promptly after receipt of a written request therefor. Under certain
            circumstances set forth in the Rights Agreement, Rights issued to,
            or held by, any Person who is, was or becomes an Acquiring Person or
            any Affiliate or Associate thereof (as such terms are defined in the
            Rights

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            Agreement), whether currently held by or on behalf of such Person or
            by any subsequent holder, may become null and void.

With respect to such certificates containing the foregoing legend, until the
earlier of (i) the Distribution Date and (ii) the Expiration Date, the Rights
associated with the Common Stock represented by such certificates shall be
evidenced by such certificates alone and registered holders of Common Stock
shall also be the registered holders of the associated Rights. Notwithstanding
this Section 3(c), the omission of a legend shall not affect the enforceability
of any part of this Rights Agreement or the rights of any holder of the Rights.

      (d) Until the earlier of the Distribution Date and the Expiration Date,
the transfer of any certificates representing shares of Common Stock in respect
of which Rights have been issued shall also constitute the transfer of the
Rights associated with such shares of Common Stock. In the event that the
Company purchases or acquires any shares of Common Stock after the Record Date
but prior to the Distribution Date, any Rights associated with such shares of
Common Stock shall be deemed cancelled and retired so that the Company shall not
be entitled to exercise any Rights associated with the shares of Common Stock
which are no longer outstanding.

      Section 4. Form of Rights Certificates.

      (a) The Rights Certificates (and the forms of election to purchase,
certification and assignment to be printed on the reverse thereof) shall each be
substantially in the form set forth in Exhibit B hereto and may have such marks
of identification or designation and such legends, summaries or endorsements
printed thereon as the Company may deem appropriate and as are not inconsistent
with the provisions of this Agreement, or as may be required to comply with any
applicable law or with any rule or regulation made pursuant thereto or with any
rule or regulation of any stock exchange or over-the-counter market on which the
Rights may from time to time be listed, or to conform to usage. Subject to the
provisions of Sections 7, 11 and 22 hereof, the Rights Certificates, whenever
distributed, shall entitle the holders thereof to purchase such number of one
one-thousandths of a share of Preferred Stock as shall be set forth therein at
the price set forth therein (such exercise price per one one-thousandth of a
share, the "Purchase Price"), but the amount and type of securities purchasable
upon the exercise of each Right and the Purchase Price thereof shall be subject
to adjustment as provided herein.

      (b) Any Rights Certificate issued pursuant to Section 3, Section 11(i) or
Section 22 hereof that represents Rights beneficially owned by persons known to
be: (i) an Acquiring Person or an Associate or Affiliate of an Acquiring Person,
(ii) a transferee of an Acquiring Person (or of any such Associate or Affiliate)
who becomes a transferee after the Acquiring Person becomes such, or (iii) a
transferee of an Acquiring Person (or of any such Associate or Affiliate) who
becomes a transferee prior to or concurrently with the Acquiring Person becoming
such and receives such Rights pursuant to either (A) a transfer (whether or not
for consideration) from the Acquiring Person to holders of equity interests in
such Acquiring Person or to any Person with whom such Acquiring Person has any
continuing agreement, arrangement or understanding (whether or not in writing)
regarding the transferred Rights or (B) a transfer which the Board has
determined is part of a plan, arrangement or understanding (whether or not in

                                      -8-
<PAGE>

writing) that has as a primary purpose or effect avoidance of Section 7(e)
hereof, and any Rights Certificate issued pursuant to Section 6 or Section 11
hereof upon transfer, exchange, replacement or adjustment of any other Rights
Certificate referred to in this sentence, shall contain (to the extent feasible)
the following legend:

            The Rights represented by this Rights Certificate are or were
            beneficially owned by a Person who was or became an Acquiring Person
            or an Affiliate or Associate of an Acquiring Person (as such terms
            are defined in the Rights Agreement). Accordingly, this Rights
            Certificate and the Rights represented hereby may become null and
            void in the circumstances specified in Section 7(e) of such
            Agreement.

The provisions of Section 7(e) hereof shall be operative whether or not the
foregoing legend is contained on any such Rights Certificate.

      Section 5. Countersignature and Registration.

      (a) The Rights Certificates shall be executed on behalf of the Company by
its Chairman of the Board, President or any Vice President, either manually or
by facsimile signature, and shall have affixed thereto the Company's seal or a
facsimile thereof, which shall be attested by the Secretary or an Assistant
Secretary of the Company, either manually or by facsimile signature. The Rights
Certificates shall be manually countersigned by the Rights Agent and shall not
be valid for any purpose unless so countersigned. In case any officer of the
Company who shall have signed any of the Rights Certificates shall cease to be
such officer of the Company before countersignature by the Rights Agent and
issuance and delivery by the Company, such Rights Certificates, nevertheless,
may be countersigned by the Rights Agent and issued and delivered by the Company
with the same force and effect as though the person who signed such Rights
Certificates had not ceased to be such officer of the Company; and any Rights
Certificates may be signed on behalf of the Company by any person who, at the
actual date of the execution of such Rights Certificate, shall be a proper
officer of the Company to sign such Rights Certificate, although at the date of
the execution of this Rights Agreement any such person was not such an officer.

      (b) Following the Distribution Date, the Rights Agent shall keep or cause
to be kept, at its office designated as the appropriate place for surrender of
Rights Certificates upon exercise or transfer, books for registration and
transfer of the Rights Certificates issued hereunder. Such books shall show the
names and addresses of the respective holders of the Rights Certificates, the
number of Rights evidenced on its face by each of the Rights Certificates, the
Rights Certificate number and the date of each of the Rights Certificates.

      Section 6. Transfer, Split Up, Combination and Exchange of Rights
Certificates; Mutilated, Destroyed, Lost or Stolen Rights Certificates.

      (a) Subject to the provisions of Section 4(b), Section 7(e) and Section 14
hereof, at any time after the close of business on the Distribution Date, and at
or prior to the close of

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business on the Expiration Date, any Rights Certificate or Certificates (other
than Rights Certificates representing Rights that have become void pursuant to
Section 7(e) hereof or that have been exchanged pursuant to Section 24 hereof)
may be transferred, split up, combined or exchanged for another Rights
Certificate or Certificates, entitling the registered holder to purchase a like
number of one one-thousandths of a share of Preferred Stock (or, following a
Triggering Event, Common Stock, other securities, cash or other assets, as the
case may be) as the Rights Certificate or Certificates surrendered then entitled
such holder (or former holder in the case of a transfer) to purchase. Any
registered holder desiring to transfer, split up, combine or exchange any Rights
Certificate or Certificates shall make such request in writing delivered to the
Rights Agent, and shall surrender the Rights Certificate or Certificates to be
transferred, split up, combined or exchanged, with the form of assignment and
certificate appropriately executed, at the office of the Rights Agent designated
for such purpose. Neither the Rights Agent nor the Company shall be obligated to
take any action whatsoever with respect to the transfer of any such surrendered
Rights Certificate until the registered holder shall have completed and signed
the certificate contained in the form of assignment on the reverse side of such
Rights Certificate and shall have provided such additional evidence of the
identity of the Beneficial Owner (or former Beneficial Owner) or Affiliates or
Associates thereof as the Company shall reasonably request. Thereupon the Rights
Agent shall, subject to Section 4(b), Section 7(e) and Section 14 hereof,
countersign and deliver to the Person entitled thereto a Rights Certificate or
Rights Certificates, as the case may be, as so requested. The Company may
require payment of a sum sufficient to cover any tax or governmental charge that
may be imposed in connection with any transfer, split up, combination or
exchange of Rights Certificates.

      (b) Upon receipt by the Company and the Rights Agent of evidence
reasonably satisfactory to them of the loss, theft, destruction or mutilation of
a Rights Certificate, and, in case of loss, theft or destruction, of indemnity
or security reasonably satisfactory to them, and reimbursement to the Company
and the Rights Agent of all reasonable expenses incidental thereto, and upon
surrender to the Rights Agent and cancellation of the Rights Certificate if
mutilated, the Company will execute and deliver a new Rights Certificate of like
tenor to the Rights Agent for countersignature and delivery to the registered
owner in lieu of the Rights Certificate so lost, stolen, destroyed or mutilated.

      Section 7. Exercise of Rights; Purchase Price; Expiration Date of
Rights.

      (a) Subject to Section 7(e) hereof, the registered holder of any Rights
Certificate may exercise the Rights evidenced thereby (except as otherwise
provided herein including, without limitation, the restrictions on
exercisability set forth in Section 9(c), Section 11(a)(iii) and Section 23
hereof) in whole or in part at any time after the Distribution Date upon
surrender of the Rights Certificate, with the form of election to purchase and
the certificate on the reverse side thereof duly executed, to the Rights Agent
at the office of the Rights Agent designated for such purpose, together with
payment of the aggregate Purchase Price with respect to the total number of one
one-thousandths of a share of Preferred Stock (or other shares, securities, cash
or other assets, as the case may be) as to which such surrendered Rights are
then exercisable, at or prior to the earliest of (i) the Final Expiration Date,
(ii) the time at which the Rights expire as provided in Section 13(d) hereof,
(iii) the time at which the Rights are redeemed as provided in Section 23 hereof
(the "Redemption Date") and (iv) the time at which such Rights are exchanged as

                                      -10-
<PAGE>

provided in Section 24 hereof (the earliest of (i), (ii), (iii) and (iv) being
herein referred to as the "Expiration Date").

      (b) The Purchase Price for each one one-thousandth of a share of Preferred
Stock pursuant to the exercise of a Right shall initially be $80 and shall be
subject to adjustment from time to time as provided in Sections 11 and 13(a)
hereof and shall be payable in lawful money of the United States of America in
accordance with paragraph (c) below.

      (c) Upon receipt of a Rights Certificate representing exercisable Rights,
with the form of election to purchase and the certificate duly executed,
accompanied by payment, with respect to each Right so exercised, of the Purchase
Price per one one-thousandth of a share of Preferred Stock (or other shares,
securities, cash or other assets, as the case may be) to be purchased and an
amount equal to any applicable transfer tax, the Rights Agent shall, subject to
Section 20(k) hereof, thereupon promptly (i) (A) requisition from any transfer
agent of the shares of Preferred Stock (or make available, if the Rights Agent
is the transfer agent for such shares) certificates for the total number of one
one-thousandths of a share of Preferred Stock to be purchased and the Company
hereby authorizes its transfer agent to comply with such requests, or (B) if the
Company shall have elected to deposit the total number of shares of Preferred
Stock issuable upon exercise of the Rights hereunder with a depositary agent,
requisition from the depositary agent depositary receipts representing such
number of one one-thousandths of a share of Preferred Stock as are to be
purchased (in which case certificates for the shares of Preferred Stock
represented by such receipts shall be deposited by the transfer agent with the
depositary agent) and the Company hereby directs the depositary agent to comply
with such requests, (ii) requisition from the Company the amount of cash, if
any, to be paid in lieu of fractional shares in accordance with Section 14
hereof, (iii) after receipt of such certificates or depositary receipts, cause
the same to be delivered to or upon the order of the registered holder of such
Rights Certificate, registered in such name or names as may be designated by
such holder, and (iv) after receipt thereof, deliver such cash, if any, to or
upon the order of the registered holder of such Rights Certificate. The payment
of the Purchase Price (as such amount may be reduced pursuant to Section
11(a)(iii) hereof) may be made in cash or by certified bank check or money order
payable to the order of the Company. In the event that the Company is obligated
to issue other securities (including Common Stock) of the Company, pay cash
and/or distribute other property pursuant to Section 11(a) hereof, the Company
shall make all arrangements necessary so that such other securities, cash and/or
other property are available for distribution by the Rights Agent, if and when
appropriate.

      (d) In case the registered holder of any Rights Certificate shall exercise
less than all the Rights evidenced thereby, a new Rights Certificate evidencing
Rights equivalent to the Rights remaining unexercised shall be issued by the
Rights Agent and delivered to, or upon the order of, the registered holder of
such Rights Certificate, registered in such name or names as may be designated
by such holder, subject to the provisions of Section 14 hereof.

      (e) Notwithstanding anything in this Agreement to the contrary, from and
after the first occurrence of a Section 11(a)(ii) Event, any Rights beneficially
owned by (i) an Acquiring Person or an Associate or Affiliate of an Acquiring
Person, (ii) a transferee of an Acquiring Person (or of any such Associate or
Affiliate) who becomes a transferee after the Acquiring

                                      -11-
<PAGE>

Person becomes such, or (iii) a transferee of an Acquiring Person (or of any
such Associate or Affiliate) who becomes a transferee prior to or concurrently
with the Acquiring Person becoming such and receives such Rights pursuant to
either (A) a transfer (whether or not for consideration) from the Acquiring
Person to holders of equity interests in such Acquiring Person or to any Person
with whom the Acquiring Person has any continuing agreement, arrangement or
understanding (whether or not in writing) regarding the transferred Rights or
(B) a transfer which the Board has determined is part of a plan, arrangement or
understanding (whether or not in writing) that has as a primary purpose or
effect avoidance of this Section 7(e), shall become null and void without any
further action and no holder of such Rights shall have any rights whatsoever
with respect to such Rights, whether under any provision of this Agreement or
otherwise. No Rights Certificate shall be issued at any time upon the transfer
of any Rights to an Acquiring Person whose Rights would be void pursuant to the
preceding sentence or any Associate or Affiliate thereof or to any nominee of
such Acquiring Person, Associate or Affiliate; and any Rights Certificate
delivered to the Rights Agent for transfer to an Acquiring Person whose Rights
would be void pursuant to the preceding sentence shall be cancelled. The Company
shall use all reasonable efforts to insure that the provisions of this Section
7(e) and Section 4(b) hereof are complied with, but shall have no liability to
any holder of Rights Certificates or other Person as a result of its failure to
make any determinations with respect to an Acquiring Person or its Affiliates,
Associates or transferees hereunder.

      (f) Notwithstanding anything in this Agreement to the contrary, neither
the Rights Agent nor the Company shall be obligated to undertake any action with
respect to a registered holder upon the occurrence of any purported transfer or
exercise as set forth in this Section 7 unless such registered holder shall have
(i) completed and signed the certificate following the form of assignment or
election to purchase set forth on the reverse side of the Rights Certificate
surrendered for such assignment or exercise, and (ii) provided such additional
evidence of the identity of the Beneficial Owner (or former Beneficial Owner) or
any Affiliates or Associates thereof as the Company shall reasonably request.

      Section 8. Cancellation and Destruction of Rights Certificates. All
Rights Certificates surrendered for the purpose of exercise, transfer, split up,
combination or exchange shall, if surrendered to the Company or any of its
agents, be delivered to the Rights Agent for cancellation or in cancelled form,
or, if surrendered to the Rights Agent, shall be cancelled by it, and no Rights
Certificates shall be issued in lieu thereof except as expressly permitted by
any of the provisions of this Agreement. The Company shall deliver to the Rights
Agent for cancellation and retirement, and the Rights Agent shall so cancel and
retire, any other Rights Certificate purchased or acquired by the Company
otherwise than upon the exercise thereof. The Rights Agent shall deliver all
cancelled Rights Certificates to the Company, or shall, at the written request
of the Company, destroy such cancelled Rights Certificates, and in such case
shall deliver a certificate of destruction thereof to the Company.

      Section 9. Reservation and Availability of Capital Stock.

      (a) The Company covenants and agrees that it will cause to be reserved and
kept available out of its authorized and unissued shares of Preferred Stock
(and, following the occurrence of a Triggering Event, out of its authorized and
unissued shares of Common Stock

                                      -12-
<PAGE>

and/or other securities or out of its authorized and issued shares held in its
treasury), the number of shares of Preferred Stock (and, following the
occurrence of a Triggering Event, Common Stock and/or other securities) that, as
provided in this Agreement including Section 11(a)(iii) hereof, will be
sufficient to permit the exercise in full of all outstanding Rights.

      (b) So long as the shares of Preferred Stock (and, following the
occurrence of a Section 11(a)(ii) Event, Common Stock and/or other securities)
issuable and deliverable upon the exercise of the Rights may be listed on any
national securities exchange or automated quotation system, the Company shall
use its best efforts to cause, from and after such time as the Rights become
exercisable, all shares reserved for such issuance to be so listed upon official
notice of issuance upon such exercise.

      (c) The Company shall use its best efforts to (i) file, as soon as
practicable following the earliest date after the first occurrence of a Section
11(a)(ii) Event on which the consideration to be delivered by the Company upon
exercise of the Rights has been determined in accordance with Section 11(a)(iii)
hereof, or as soon as is required by law following the Distribution Date, as the
case may be, a registration statement under the Act, with respect to the
securities purchasable upon exercise of the Rights on an appropriate form, (ii)
cause such registration statement to become effective as soon as practicable
after such filing, (iii) cause such registration statement to remain effective
(with a prospectus at all times meeting the requirements of the Act) until the
earlier of (A) the date as of which the Rights are no longer exercisable for
such securities, and (B) the Expiration Date, and (iv) obtain such other
regulatory approvals as may be necessary for it to issue securities purchasable
upon the exercise of the Rights. The Company will also take such action as may
be appropriate under, or to ensure compliance with, the securities or "blue sky"
laws of the various states in connection with the exercisability of the Rights.
The Company may temporarily suspend, for a period of time not to exceed ninety
(90) days after the date set forth in clause (i) of the first sentence of this
Section 9(c), the exercisability of the Rights in order to prepare and file such
registration statement and permit it to become effective or to obtain any other
required regulatory approval in connection with the exercisability of the
Rights. Upon any such suspension, the Company shall issue a public announcement
stating that the exercisability of the Rights has been temporarily suspended, as
well as a public announcement at such time as the suspension is no longer in
effect. Notwithstanding any provision of this Agreement to the contrary, the
Rights shall not be exercisable in any jurisdiction unless the requisite
registration or qualification in such jurisdiction shall have been effected or
obtained.

      (d) The Company covenants and agrees that it will take all such action as
may be necessary to ensure that all one one-thousandths of a share of Preferred
Stock (and, following the occurrence of a Triggering Event, Common Stock and/or
other securities) delivered upon exercise of Rights shall, at the time of
delivery of the certificates for such shares (subject to payment of the Purchase
Price), be duly and validly authorized and issued and fully paid and
nonassessable.

      (e) The Company further covenants and agrees that it will pay when due and
payable any and all federal and state transfer taxes and charges that may be
payable in respect of the issuance or delivery of the Rights Certificates and of
any certificates for a number of one one-thousandths of a share of Preferred
Stock (or Common Stock and/or other securities, as the case

                                      -13-
<PAGE>

may be) upon the exercise of Rights. The Company shall not, however, be required
(i) to pay any transfer tax that may be payable in respect of any transfer or
delivery of Rights Certificates to a Person other than, or the issuance or
delivery of a number of one one-thousandths of a share of Preferred Stock (or
Common Stock and/or other securities, as the case may be) in respect of a name
other than that of, the registered holder of the Rights Certificate evidencing
Rights surrendered for exercise or (ii) to issue or deliver any certificates for
a number of one one-thousandths of a share of Preferred Stock (or Common Stock
and/or other securities, as the case may be) in a name other than that of the
registered holder upon the exercise of any Rights until such tax shall have been
paid (any such tax being payable by the holder of such Rights Certificate at the
time of surrender) or until it has been established to the Company's
satisfaction that no such tax is due.

      Section 10. Preferred Stock Record Date. Each Person in whose name
any certificate for a number of one one-thousandths of a share of Preferred
Stock (or Common Stock and/or other securities, as the case may be) is issued
upon the exercise of Rights shall for all purposes be deemed to have become the
holder of record of such fractional shares of Preferred Stock (or Common Stock
and/or other securities, as the case may be) represented thereby on, and such
certificate shall be dated, the date upon which the Rights Certificate
evidencing such Rights was duly surrendered with the forms of election and
certification duly executed and payment of the Purchase Price (and all
applicable transfer taxes) was made; provided, however, that if the date of such
surrender and payment is a date upon which the Preferred Stock (or Common Stock
and/or other securities, as the case may be) transfer books of the Company are
closed, such Person shall be deemed to have become the record holder of such
shares (fractional or otherwise) on, and such certificate shall be dated, the
next succeeding Business Day on which the Preferred Stock (or Common Stock
and/or other securities, as the case may be) transfer books of the Company are
open. Prior to the exercise of the Rights evidenced thereby, the holder of a
Rights Certificate, as such, shall not be entitled to any rights of a
stockholder of the Company with respect to securities for which the Rights shall
be exercisable, including, without limitation, the right to vote, to receive
dividends or other distributions or to exercise any preemptive rights, and shall
not be entitled to receive any notice of any proceedings of the Company, except
as provided herein.

      Section 11. Adjustment of Purchase Price, Number and Kind of Shares
or Number of Rights. The Purchase Price, the number and kind of shares covered
by each Right and the number of Rights outstanding are subject to adjustment
from time to time as provided in this Section 11.

      (a) (i) In the event the Company shall at any time after the date of this
Agreement (A) declare a dividend on the Preferred Stock payable in shares of
Preferred Stock, (B) subdivide the outstanding Preferred Stock, (C) combine the
outstanding Preferred Stock into a smaller number of shares, or (D) issue any
shares of its capital stock in a reclassification of the Preferred Stock
(including any such reclassification in connection with a consolidation or
merger in which the Company is the continuing or surviving corporation), except
as otherwise provided in this Section 11(a) and Section 7(e) hereof, the
Purchase Price in effect at the time of the record date for such dividend or of
the effective date of such subdivision, combination or reclassification, and the
number and kind of shares of Preferred Stock or capital stock, as the

                                      -14-
<PAGE>

case may be, issuable on such date, shall be proportionately adjusted so that
the holder of any Right exercised after such time shall be entitled to receive,
upon payment of the Purchase Price then in effect, the aggregate number and kind
of shares of Preferred Stock or capital stock, as the case may be, which, if
such Right had been exercised immediately prior to such date and at a time when
the Preferred Stock transfer books of the Company were open, he would have owned
upon such exercise and been entitled to receive by virtue of such dividend,
subdivision, combination or reclassification. If an event occurs that would
require an adjustment under both this Section 11(a)(i) and Section 11(a)(ii)
hereof, the adjustment provided for in this Section 11(a)(i) shall be in
addition to, and shall be made prior to, any adjustment required pursuant to
Section 11(a)(ii) hereof.

            (ii) Subject to Section 24 of this Agreement, in the event that any
Person, alone or together with its Affiliates or Associates, becomes an
Acquiring Person (other than pursuant to a Permitted Offer), then, promptly
following the first occurrence of such event, proper provision shall be made so
that each holder of a Right (except as provided below and in Section 7(e)
hereof) shall thereafter have the right to receive (subject to the last sentence
of Section 23(a)), upon exercise thereof at the then current Purchase Price in
accordance with the terms of this Agreement, in lieu of a number of one
one-thousandths of a share of Preferred Stock, such number of shares of Common
Stock of the Company that equals the result obtained by (x) multiplying the then
current Purchase Price by the then number of one one-thousandths of a share of
Preferred Stock for which a Right was exercisable immediately prior to the first
occurrence of a Section 11(a)(ii) Event, and (y) dividing that product (which,
following such first occurrence, shall thereafter be referred to as the
"Purchase Price" for each Right and for all purposes of this Agreement) by 50%
of the current market price (determined pursuant to Section 11(d) hereof) per
share of Common Stock on the date of such first occurrence (such number of
shares, the "Adjustment Shares").

            (iii) In the event that the number of shares of Common Stock that
are authorized by the Company's Certificate of Incorporation but not outstanding
or reserved for issuance for purposes other than upon exercise of the Rights are
not sufficient to permit the exercise in full of the Rights in accordance with
the foregoing subparagraph (ii) of this Section 11(a), the Company shall: (A)
determine the excess of (1) the value of the Adjustment Shares issuable upon the
exercise of a Right (the "Current Value") over (2) the Purchase Price (such
excess, the "Spread"), and (B) with respect to each Right, make adequate
provision to substitute for the Adjustment Shares, upon payment of the
applicable Purchase Price, (1) cash, (2) a reduction in the Purchase Price, (3)
Common Stock or other equity securities of the Company (including, without
limitation, shares, or units of shares, of preferred stock which the Board has
deemed to have the same value as shares of Common Stock (such shares of
preferred stock, "common stock equivalents")), (4) debt securities of the
Company, (5) other assets, or (6) any combination of the foregoing, having an
aggregate value equal to the Current Value, where such aggregate value has been
determined by the Board based upon the advice of a nationally recognized
investment banking firm selected by the Board; provided, however, if the Company
shall not have made adequate provision to deliver value pursuant to clause (B)
above within thirty (30) days following the later of (x) the first occurrence of
a Section 11(a)(ii) Event and (y) the date on which the Company's right of
redemption pursuant to Section 23(a) expires (the later of (x) and (y) being
referred to herein as the "Section 11(a)(ii) Trigger Date"), then the

                                      -15-
<PAGE>

Company shall be obligated to deliver, upon the surrender for exercise of a
Right and without requiring payment of the Purchase Price, shares of Common
Stock (to the extent available) and then, if necessary, cash, which shares
and/or cash have an aggregate value equal to the Spread. If the Board shall
determine in good faith that it is likely that sufficient additional shares of
Common Stock could be authorized for issuance upon exercise in full of the
Rights, the thirty (30) day period set forth above may be extended to the extent
necessary, but not more than ninety (90) days after the Section 11(a)(ii)
Trigger Date, in order that the Company may seek shareholder approval for the
authorization of such additional shares (such period, as it may be extended, the
"Substitution Period"). To the extent that the Company determines that some
action need be taken pursuant to the first and/or second sentences of this
Section 11(a)(iii), the Company (x) shall provide, subject to Section 7(e)
hereof, that such action shall apply uniformly to all outstanding Rights, and
(y) may suspend the exercisability of the Rights until the expiration of the
Substitution Period in order to seek any authorization of additional shares
and/or to decide the appropriate form of distribution to be made pursuant to
such first sentence and to determine the value thereof. In the event of any such
suspension, the Company shall issue a public announcement stating that the
exercisability of the Rights has been temporarily suspended, as well as a public
announcement at such time as the suspension is no longer in effect. For purposes
of this Section 11(a)(iii), the value of the Common Stock shall be the current
market price (as determined pursuant to Section 11(d) hereof) per share of the
Common Stock on the Section 11(a)(ii) Trigger Date and the value of any "common
stock equivalent" shall be deemed to have the same value as the Common Stock on
such date.

      (b) In case the Company shall fix a record date for the issuance of
rights, options or warrants to all holders of Preferred Stock entitling them to
subscribe for or purchase (for a period expiring within forty-five (45) calendar
days after such record date) Preferred Stock (or shares having the same rights,
privileges and preferences as the shares of Preferred Stock ("equivalent
preferred stock")) or securities convertible into Preferred Stock or equivalent
preferred stock at a price per share of Preferred Stock or per share of
equivalent preferred stock (or having a conversion price per share, if a
security convertible into Preferred Stock or equivalent preferred stock) less
than the current market price (as determined pursuant to Section 11(d) hereof)
per share of Preferred Stock on such record date, the Purchase Price to be in
effect after such record date shall be determined by multiplying the Purchase
Price in effect immediately prior to such record date by a fraction, the
numerator of which shall be the number of shares of Preferred Stock outstanding
on such record date, plus the number of shares of Preferred Stock which the
aggregate offering price of the total number of shares of Preferred Stock and/or
equivalent preferred stock so to be offered (and/or the aggregate initial
conversion price of the convertible securities so to be offered) would purchase
at such current market price, and the denominator of which shall be the number
of shares of Preferred Stock outstanding on such record date, plus the number of
additional shares of Preferred Stock and/or equivalent preferred stock to be
offered for subscription or purchase (or into which the convertible securities
so to be offered are initially convertible). In case such subscription price may
be paid by delivery of consideration part or all of which may be in a form other
than cash, the value of such consideration shall be as determined in good faith
by the Board, whose determination shall be described in a statement filed with
the Rights Agent and shall be conclusive for all purposes. Shares of Preferred
Stock owned by or held for the account of the Company shall not be deemed
outstanding for the purpose of any such computation. Such adjustment shall be
made successively whenever such a

                                      -16-
<PAGE>

record date is fixed, and in the event that such rights, options or warrants are
not so issued, the Purchase Price shall be adjusted to be the Purchase Price
which would then be in effect if such record date had not been fixed.

      (c) In case the Company shall fix a record date for a distribution to all
holders of Preferred Stock (including any such distribution made in connection
with a consolidation or merger in which the Company is the continuing
corporation) of evidences of indebtedness, cash (other than a regular quarterly
cash dividend out of the earnings or retained earnings of the Company), assets
(other than a dividend payable in Preferred Stock, but including any dividend
payable in stock other than Preferred Stock) or subscription rights or warrants
(excluding those referred to in Section 11(b) hereof), the Purchase Price to be
in effect after such record date shall be determined by multiplying the Purchase
Price in effect immediately prior to such record date by a fraction, the
numerator of which shall be the current market price (as determined pursuant to
Section 11(d) hereof) per share of Preferred Stock on such record date, less the
fair market value (as determined in good faith by the Board, whose determination
shall be described in a statement filed with the Rights Agent and shall be
conclusive for all purposes) of the portion of the cash, assets or evidences of
indebtedness so to be distributed or of such subscription rights or warrants
applicable to a share of Preferred Stock and the denominator of which shall be
such current market price (as determined pursuant to Section 11(d) hereof) per
share of Preferred Stock on such record date. Such adjustments shall be made
successively whenever such a record date is fixed, and in the event that such
distribution is not so made, the Purchase Price shall be adjusted to be the
Purchase Price which would have been in effect if such record date had not been
fixed.

      (d) (i) For the purpose of any computation hereunder, other than
computations made pursuant to Section 11(a)(iii) hereof, the "current market
price" per share of Common Stock on any date shall be deemed to be the average
of the daily closing prices per share of such Common Stock for the thirty (30)
consecutive Trading Days (as such term is hereinafter defined) immediately prior
to such date, and for purposes of computations made pursuant to Section
11(a)(iii) hereof, the "current market price" per share of Common Stock on any
date shall be deemed to be the average of the daily closing prices per share of
such Common Stock for the ten (10) consecutive Trading Days immediately
following such date; provided, however, that in the event that the current
market price per share of the Common Stock is determined during a period
following the announcement by the issuer of such Common Stock of (A) a dividend
or distribution on such Common Stock payable in shares of such Common Stock or
securities convertible into shares of such Common Stock (other than the Rights),
or (B) any subdivision, combination or reclassification of such Common Stock,
and prior to the expiration of the requisite thirty (30) Trading Day or ten (10)
Trading Day period, as set forth above, after the ex-dividend date for such
dividend or distribution, or the record date for such subdivision, combination
or reclassification occurs, then, and in each such case, the "current market
price" shall be properly adjusted to take into account ex-dividend or post
record date trading. The closing price for each day shall be the last sale
price, regular way, or, in case no such sale takes place on such day, the
average of the closing bid and asked prices, regular way, in either case as
reported in the principal consolidated transaction reporting system with respect
to securities listed or admitted to trading on the principal national securities
exchange on which the shares of Common Stock are listed or admitted to trading
or, if the shares of Common Stock are not listed or admitted to trading on any
national securities exchange, the last quoted price or, if not so

                                      -17-
<PAGE>

quoted, the average of the high bid and the low asked prices in the
over-the-counter market, as reported by The Nasdaq Stock Market, Inc. ("Nasdaq")
or such other system then in use, or, if on any such date the shares of Common
Stock are not quoted by any such organization, the average of the closing bid
and asked prices as furnished by a professional market maker making a market in
the Common Stock selected by the Board. All references in this Section to
closing prices, last quoted prices or other stock prices mean prices during
regular trading hours, without giving effect to any after-hours or extended
hours trading. If on any such date no market maker is making a market in the
Common Stock, the fair value of such shares on such date shall be as determined
in good faith by the Board, whose determination shall be described in a
statement filed with the Rights Agent and shall be conclusive for all purposes.
The term "Trading Day" shall mean a day on which Nasdaq or any national
securities exchange on which the shares of Common Stock are listed or admitted
to trading is open for the transaction of business or, if the shares of Common
Stock are not listed or admitted to trading on Nasdaq or any national securities
exchange, a Business Day. If the Common Stock is not publicly held or not so
listed or traded, "current market price" per share shall mean the fair value per
share as determined in good faith by the Board, whose determination shall be
described in a statement filed with the Rights Agent and shall be conclusive for
all purposes.

            (ii) For the purpose of any computation hereunder, the "current
market price" per share of Preferred Stock shall be determined in the same
manner as set forth above for the Common Stock in clause (i) of this Section
11(d) (other than the last sentence thereof). If the current market price per
share of Preferred Stock cannot be determined in the manner provided above or if
the Preferred Stock is not publicly held or listed or traded in a manner
described in clause (i) of this Section 11(d), the "current market price" per
share of Preferred Stock shall be conclusively deemed to be an amount equal to
1000 (as such number may be appropriately adjusted for such events as stock
splits, stock dividends and recapitalizations with respect to the Common Stock
occurring after the date of this Agreement) multiplied by the current market
price per share of the Common Stock. If neither the Common Stock nor the
Preferred Stock is publicly held or so listed or traded, "current market price"
per share of the Preferred Stock shall mean the fair value per share as
determined in good faith by the Board, which determination shall be described in
a statement filed with the Rights Agent and shall be conclusive for all
purposes. For all purposes of this Agreement, the "current market price" of one
one-thousandth of a share of Preferred Stock shall be equal to the "current
market price" of one share of Preferred Stock divided by 1000.

      (e) Anything herein to the contrary notwithstanding, no adjustment in the
Purchase Price shall be required unless such adjustment would require an
increase or decrease of at least one percent (1%) in the Purchase Price;
provided, however, that any adjustments which by reason of this Section 11(e)
are not required to be made shall be carried forward and taken into account in
any subsequent adjustment. All calculations under this Section 11 shall be made
to the nearest cent or to the nearest ten-millionth of a share of Preferred
Stock, or hundred-thousandth of a share of Common Stock or other security, as
the case may be. Notwithstanding the first sentence of this Section 11(e), any
adjustment required by this Section 11 shall be made no later than the earlier
of (i) three years from the date of the transaction which mandates such
adjustment, or (ii) the Expiration Date.

                                      -18-
<PAGE>

      (f) If as a result of an adjustment made pursuant to Section 11(a)(ii) or
Section 13(a) hereof, the holder of any Right thereafter exercised shall become
entitled to receive any securities other than Preferred Stock, thereafter the
number of such other securities so receivable upon exercise of any Right and the
Purchase Price thereof shall be subject to adjustment from time to time in a
manner and on terms as nearly equivalent as practicable to the provisions with
respect to the Preferred Stock contained in Sections 11(a), (b), (c), (e), (g),
(h), (i), (j), (k) and (m), and the provisions of Sections 7, 9, 10, 13 and 14
hereof with respect to the Preferred Stock shall apply on like terms to any such
other securities; provided, however, that the Company shall not be liable for
its inability to reserve and keep available for issuance upon exercise of the
Rights pursuant to Section 11(a)(ii) a number of shares of Common Stock greater
than the number then authorized by the Company's Certificate of Incorporation
but not outstanding or reserved for other purposes.

      (g) All Rights originally issued by the Company subsequent to any
adjustment made to the Purchase Price hereunder shall evidence the right to
purchase, at the adjusted Purchase Price, the number of one one-thousandths of a
share of Preferred Stock purchasable from time to time hereunder upon exercise
of the Rights, all subject to further adjustment as provided herein.

      (h) Unless the Company shall have exercised its election as provided in
Section 11(i), upon each adjustment of the Purchase Price as a result of the
calculations made in Sections 11(b) and (c), each Right outstanding immediately
prior to the making of such adjustment shall thereafter evidence the right to
purchase, at the adjusted Purchase Price, that number of one one-thousandths of
a share of Preferred Stock (calculated to the nearest ten-millionth) obtained by
(i) multiplying (x) the number of one one-thousandths of a share covered by a
Right immediately prior to this adjustment, by (y) the Purchase Price in effect
immediately prior to such adjustment of the Purchase Price, and (ii) dividing
the product so obtained by the Purchase Price in effect immediately after such
adjustment of the Purchase Price.

      (i) The Company may elect on or after the date of any adjustment of the
Purchase Price to adjust the number of Rights, in lieu of any adjustment in the
number of one one-thousandths of a share of Preferred Stock purchasable upon the
exercise of a Right. Each of the Rights outstanding after the adjustment in the
number of Rights shall be exercisable for the number of one one-thousandths of a
share of Preferred Stock for which a Right was exercisable immediately prior to
such adjustment. Each Right held of record prior to such adjustment of the
number of Rights shall become that number of Rights (calculated to the nearest
one-hundred- thousandth) obtained by dividing the Purchase Price in effect
immediately prior to adjustment of the Purchase Price by the Purchase Price in
effect immediately after adjustment of the Purchase Price. The Company shall
make a public announcement of its election to adjust the number of Rights,
indicating the record date for the adjustment, and, if known at the time, the
amount of the adjustment to be made. This record date may be the date on which
the Purchase Price is adjusted or any day thereafter, but, if the Rights
Certificates have been issued, shall be at least ten (10) days later than the
date of the public announcement. If Rights Certificates have been issued, upon
each adjustment of the number of Rights pursuant to this Section 11(i), the
Company shall, as promptly as practicable, cause to be distributed to holders of
record of Rights Certificates on such record date Rights Certificates
evidencing, subject to Section 14 hereof, the additional Rights to which such
holders shall be entitled as a result of such adjustment, or, at the option of

                                      -19-
<PAGE>

the Company, shall cause to be distributed to such holders of record in
substitution and replacement for the Rights Certificates held by such holders
prior to the date of adjustment, and upon surrender thereof, if required by the
Company, new Rights Certificates evidencing all the Rights to which such holders
shall be entitled after such adjustment. Rights Certificates so to be
distributed shall be issued, executed and countersigned in the manner provided
for herein (and may bear, at the option of the Company, the adjusted Purchase
Price) and shall be registered in the names of the holders of record of Rights
Certificates on the record date specified in the public announcement.

      (j) Irrespective of any adjustment or change in the Purchase Price or the
number of one one-thousandths of a share of Preferred Stock issuable upon the
exercise of the Rights, the Rights Certificates theretofore and thereafter
issued may continue to express the Purchase Price per one one-thousandth of a
share and the number of one one-thousandths of a share which were expressed in
the initial Rights Certificates issued hereunder.

      (k) Before taking any action that would cause an adjustment reducing the
Purchase Price below the then par value, if any, of the number of one
one-thousandths of a share of Preferred Stock issuable upon exercise of the
Rights, the Company shall take any corporate action which may, in the opinion of
its counsel, be necessary in order that the Company may validly and legally
issue such number of one one-thousandths of a share of fully paid and
nonassessable Preferred Stock at such adjusted Purchase Price.

      (l) In any case in which this Section 11 shall require that an adjustment
in the Purchase Price be made effective as of a record date for a specified
event, the Company may elect to defer until the occurrence of such event the
issuance to the holder of any Right exercised after such record date the number
of one one-thousandths of a share of Preferred Stock and other capital stock or
securities of the Company, if any, issuable upon such exercise over and above
the number of one one-thousandths of a share of Preferred Stock and other
capital stock or securities of the Company, if any, issuable upon such exercise
on the basis of the Purchase Price in effect prior to such adjustment; provided,
however, that the Company shall deliver to such holder a due bill or other
appropriate instrument evidencing such holder's right to receive such additional
shares (fractional or otherwise) or securities upon the occurrence of the event
requiring such adjustment.

      (m) Anything in this Section 11 to the contrary notwithstanding, the
Company shall be entitled to make such reductions in the Purchase Price, in
addition to those adjustments expressly required by this Section 11, as and to
the extent that in their good faith judgment the Board shall determine to be
advisable in order that any (i) consolidation or subdivision of the Preferred
Stock, (ii) issuance wholly for cash of any shares of Preferred Stock at less
than the current market price, (iii) issuance wholly for cash of shares of
Preferred Stock or securities which by their terms are convertible into or
exchangeable for shares of Preferred Stock, (iv) stock dividends or (v) issuance
of rights, options or warrants referred to in this Section 11, hereafter made by
the Company to holders of its Preferred Stock shall not be taxable to such
stockholders.

      (n) The Company covenants and agrees that it shall not, at any time after
the Distribution Date, (i) consolidate with any other Person (other than a
Subsidiary of the Company

                                      -20-
<PAGE>

in a transaction that complies with Section 11(o) hereof), (ii) merge with or
into any other Person (other than a Subsidiary of the Company in a transaction
which complies with Section 11(o) hereof), or (iii) sell or transfer (or permit
any Subsidiary to sell or transfer), in one transaction, or a series of related
transactions, assets or earning power aggregating more than 50% of the assets or
earning power of the Company and its Subsidiaries (taken as a whole) to any
other Person or Persons (other than the Company and/or any of its Subsidiaries
in one or more transactions each of which complies with Section 11(o) hereof),
if (x) at the time of or immediately after such consolidation, merger or sale
there are any charter or bylaw provisions or any rights, warrants or other
instruments or securities outstanding or agreements in effect that would
substantially diminish or otherwise eliminate the benefits intended to be
afforded by the Rights or (y) prior to, simultaneously with or immediately after
such consolidation, merger or sale, the stockholders of the Person who
constitutes, or would constitute, the "Principal Party" for purposes of Section
13(a) hereof shall have received a distribution of Rights previously owned by
such Person or any of its Affiliates or Associates. The Company shall not
consummate any consolidation, merger, sale or transfer described in clause (i),
(ii) or (iii) of the prior sentence unless prior thereto the Company and such
other Person shall have executed and delivered to the Rights Agent a
supplemental agreement evidencing compliance with this Section 11(n).

      (o) The Company covenants and agrees that, after the Distribution Date, it
will not, except as permitted by Section 23, Section 24 or Section 27 hereof,
take (or permit any Subsidiary to take) any action if at the time such action is
taken it is reasonably foreseeable that such action will diminish substantially
or otherwise eliminate the benefits intended to be afforded by the Rights.

      (p) Anything in this Agreement to the contrary notwithstanding, in the
event that the Company shall at any time after the Record Date and prior to the
Distribution Date (i) declare or pay any dividend on the outstanding shares of
Common Stock payable in shares of Common Stock, (ii) subdivide the outstanding
shares of Common Stock, or (iii) combine the outstanding shares of Common Stock
into a smaller number of shares, the number of Rights associated with each share
of Common Stock then outstanding, or issued or delivered thereafter but prior to
the Distribution Date, shall be proportionately adjusted so that the number of
Rights thereafter associated with each share of Common Stock following any such
event shall equal the result obtained by multiplying the number of Rights
associated with each share of Common Stock immediately prior to such event by a
fraction, the numerator of which shall be the number of shares of Common Stock
outstanding immediately prior to the occurrence of such event and the
denominator of which shall be the number of shares of Common Stock outstanding
immediately following the occurrence of such event.

      Section 12. Certificate of Adjusted Purchase Price or Number of
Shares. Whenever an adjustment is made as provided in Section 11 or Section 13
hereof, the Company shall promptly (a) prepare a certificate setting forth such
adjustment and a brief statement of the facts accounting for such adjustment,
(b) file with the Rights Agent, and with each transfer agent for the Preferred
Stock and the Common Stock, a copy of such certificate, and (c) mail a brief
summary thereof to each holder of a Rights Certificate (or, if prior to the
Distribution Date, to each holder of a certificate representing shares of Common
Stock) in accordance with Section 26 hereof. The Rights Agent shall be fully
protected in relying on any such certificate and on any

                                      -21-
<PAGE>

adjustment therein contained and shall not be deemed to have knowledge of any
adjustment unless and until it shall have received such certificate.

      Section 13. Consolidation, Merger or Sale or Transfer of Assets or
Earning Power.

      (a) In the event that, at any time after a Person has become an Acquiring
Person, (x) the Company shall consolidate with, or merge with and into, any
other Person (other than a Subsidiary of the Company in a transaction that
complies with Section 11(o) hereof), and the Company shall not be the continuing
or surviving corporation of such consolidation or merger, (y) any Person (other
than a Subsidiary of the Company in a transaction that complies with Section
11(o) hereof) shall consolidate with, or merge with or into, the Company, and
the Company shall be the continuing or surviving corporation of such
consolidation or merger and, in connection with such consolidation or merger,
all or part of the outstanding shares of Common Stock shall be changed into or
exchanged for stock or other securities of any other Person or cash or any other
property, or (z) the Company shall sell or otherwise transfer (or one or more of
its Subsidiaries shall sell or otherwise transfer), in one transaction or a
series of related transactions, assets or earning power aggregating more than
50% of the assets or earning power of the Company and its Subsidiaries (taken as
a whole) to any Person or Persons (other than the Company or any Subsidiary of
the Company in one or more transactions each of which complies with Section
11(o) hereof), then, and in each such case and except as contemplated by Section
13(d) hereof, proper provision shall be made so that: (i) each holder of a
Right, except as provided in Section 7(e) hereof, shall thereafter have the
right to receive, upon the exercise thereof at the then current Purchase Price
in accordance with the terms of this Agreement, such number of validly
authorized and issued, fully paid, non-assessable and freely tradeable shares of
Common Stock of the Principal Party (as such term is hereinafter defined), which
shall not be subject to any liens, encumbrances, rights of first refusal or
other adverse claims, as shall be equal to the result obtained by (1)
multiplying the then current Purchase Price by the number of one one-thousandths
of a share of Preferred Stock for which a Right is exercisable immediately prior
to the first occurrence of a Section 13 Event (or, if a Section 11(a)(ii) Event
has occurred prior to the first occurrence of a Section 13 Event, multiplying
the number of such one one-thousandths of a share for which a Right was
exercisable immediately prior to the first occurrence of a Section 11(a)(ii)
Event by the Purchase Price in effect immediately prior to such first
occurrence), and (2) dividing that product (which, following the first
occurrence of a Section 13 Event, shall be referred to as the "Purchase Price"
for each Right and for all purposes of this Agreement) by 50% of the current
market price (determined pursuant to Section 11(d)(i) hereof) per share of the
Common Stock of such Principal Party on the date of consummation of such Section
13 Event; (ii) such Principal Party shall thereafter be liable for, and shall
assume, by virtue of such Section 13 Event, all the obligations and duties of
the Company pursuant to this Agreement; (iii) the term "Company" shall
thereafter be deemed to refer to such Principal Party, it being specifically
intended that, subject to clause (v) below, the provisions of Section 11 hereof
shall apply only to such Principal Party following the first occurrence of a
Section 13 Event; (iv) such Principal Party shall take such steps (including,
but not limited to, the reservation of a sufficient number of shares of its
Common Stock) in connection with the consummation of any such transaction as may
be necessary to assure that the provisions hereof shall thereafter be
applicable, as nearly as reasonably may be, in relation to its shares of Common
Stock thereafter deliverable upon the exercise of the Rights; and (v) the
provisions of

                                      -22-
<PAGE>

Section 11(a)(ii) hereof shall be of no effect following the first occurrence of
any Section 13 Event.

      (b) "Principal Party" shall mean

            (i) in the case of any transaction described in clause (x) or (y) of
the first sentence of Section 13(a), the Person that is the issuer of any
securities into which shares of Common Stock of the Company are converted in
such merger or consolidation, and if no securities are so issued, the Person
that is the other party to such merger or consolidation; and

            (ii) in the case of any transaction described in clause (z) of the
first sentence of Section 13(a), the Person that is the party receiving the
greatest portion of the assets or earning power transferred pursuant to such
transaction or transactions;

provided, however, that in any such case, (1) if the Common Stock of such Person
is not at such time and has not been continuously over the preceding twelve (12)
month period registered under Section 12 of the Exchange Act, and such Person is
a direct or indirect Subsidiary of another Person the Common Stock of which is
and has been so registered, "Principal Party" shall refer to such other Person;
(2) in case such Person is a Subsidiary, directly or indirectly, of more than
one Person, the Common Stocks of two or more of which are and have been so
registered, "Principal Party" shall refer to whichever of such Persons is the
issuer of the Common Stock having the greatest aggregate market value; and (3)
in case such Person is owned, directly or indirectly, by a joint venture formed
by two or more Persons that are not owned, directly or indirectly, by the same
Person, the rules set forth in (1) and (2) above shall apply to each of the
chains of ownership having an interest in such joint venture as if such party
were a "Subsidiary" of both or all of such joint ventures and the Principal
Parties in each such chain shall bear the obligations set forth in this Section
13 in the same ratio as their direct or indirect interests in such Person bear
to the total of such interests.

      (c) The Company shall not consummate any such consolidation, merger, sale
or transfer unless the Principal Party shall have a sufficient number of
authorized shares of its Common Stock which have not been issued or reserved for
issuance to permit the exercise in full of the Rights in accordance with this
Section 13 and unless prior thereto the Company and such Principal Party shall
have executed and delivered to the Rights Agent a supplemental agreement
providing for the terms set forth in paragraphs (a) and (b) of this Section 13
and further providing that, as soon as practicable after the date of any
consolidation, merger or sale of assets mentioned in paragraph (a) of this
Section 13, the Principal Party will

            (i) prepare and file a registration statement under the Act, with
respect to the Rights and the securities purchasable upon exercise of the Rights
on an appropriate form, and will use its best efforts to cause such registration
statement to (A) become effective as soon as practicable after such filing and
(B) remain effective (with a prospectus at all times meeting the requirements of
the Act) until the Expiration Date;

                                      -23-
<PAGE>

            (ii) use its best efforts to qualify or register the Rights and the
securities purchasable upon exercise of the Rights under the blue sky laws of
such jurisdictions as may be necessary or appropriate; and

            (iii) deliver to holders of the Rights historical financial
statements for the Principal Party and each of its Affiliates that comply in all
respects with the requirements for registration on Form 10 under the Exchange
Act.

The provisions of this Section 13 shall similarly apply to successive mergers or
consolidations or sales or other transfers. In the event that a Section 13 Event
shall occur at the same time as, or at any time after, the occurrence of a
Section 11(a)(ii) Event, the Rights which have not theretofore been exercised
shall thereafter become exercisable in the manner described in Section 13(a).

      (d) Notwithstanding anything in this Agreement to the contrary, Section 13
shall not be applicable to a transaction described in subparagraphs (x) and (y)
of Section 13(a) if (i) such transaction is consummated with a Person or Persons
(or a wholly owned subsidiary of any such Person or Persons) who acquired shares
of Common Stock pursuant to a Permitted Offer, (ii) the price per share of
Common Stock paid in such transaction is not less than the price per share of
Common Stock paid to all holders of shares of Common Stock whose shares were
purchased pursuant to such Permitted Offer, and (iii) the form of consideration
paid in such transaction is the same as the form of consideration paid pursuant
to such Permitted Offer. Upon consummation of any such transaction contemplated
by this Section 13(d), all Rights hereunder shall expire.

      Section 14. Fractional Rights and Fractional Shares.

      (a) The Company shall not be required to issue fractions of Rights, except
prior to the Distribution Date as provided in Section 11(i) or (p) hereof, or to
distribute Rights Certificates that evidence fractional Rights. In lieu of such
fractional Rights, there shall be paid to the registered holders of the Rights
Certificates with regard to which such fractional Rights would otherwise be
issuable, an amount in cash equal to the same fraction of the current market
value of a whole Right. For purposes of this Section 14(a), the current market
value of a whole Right shall be the closing price of the Rights for the Trading
Day immediately prior to the date on which such fractional Rights would have
been otherwise issuable. The closing price of the Rights for any day shall be
the last sale price, regular way, or, in case no such sale takes place on such
day, the average of the closing bid and asked prices, regular way, in either
case as reported in the principal consolidated transaction reporting system with
respect to securities listed or admitted to trading on the principal national
securities exchange on which the Rights are listed or admitted to trading, or if
the Rights are not listed or admitted to trading on any national securities
exchange, the last quoted price or, if not so quoted, the average of the high
bid and the low asked prices in the over-the-counter market, as reported by
Nasdaq or such other system then in use or, if on any such date the Rights are
not quoted by any such organization, the average of the closing bid and asked
prices as furnished by a professional market maker making a market in the Rights
selected by the Board. All references in this Section to closing prices, last
quoted prices or other stock prices means prices during regular trading hours,
without giving effect to any after-hours or extended hours trading. If on any
such date no such market maker is making a market in the

                                      -24-
<PAGE>

Rights, the fair value of the Rights on such date as determined in good faith by
the Board shall be used, which determination shall be described in a statement
filed with Rights Agent and shall be conclusive for all purposes.

      (b) The Company shall not be required to issue fractions of shares of
Preferred Stock (other than fractions which are integral multiples of one
one-thousandth of a share of Preferred Stock) upon exercise of the Rights or to
distribute certificates that evidence fractional shares of Preferred Stock
(other than fractions which are integral multiples of one one-thousandth of a
share of Preferred Stock). Fractional shares of Preferred Stock in integral
multiples of one one-thousandth of a share of Preferred Stock may, at the
election of the Company, be evidenced by depositary receipts; provided, however,
that holders of such depositary receipts shall have all of the designations and
the powers, preferences and rights, and the qualifications, limitations and
restrictions to which they are entitled as beneficial owners of the shares of
Preferred Stock represented by such depositary receipts. In lieu of fractional
shares of Preferred Stock (other than fractions which are integral multiples of
one one-thousandth of a share of Preferred Stock), the Company shall pay to the
registered holders of Rights Certificates at the time such Rights are exercised
as herein provided an amount in cash equal to the same fraction of the current
market value of one one-thousandth of a share of Preferred Stock. For purposes
of this Section 14(b), the current market value of one one-thousandth of a share
of Preferred Stock shall be one one-thousandth of the closing price of a share
of Preferred Stock (as determined pursuant to Section 11(d)(ii) hereof) for the
Trading Day immediately prior to the date of such exercise.

      (c) Following the occurrence of a Triggering Event, the Company shall not
be required to issue fractions of shares of Common Stock upon exercise of the
Rights or to distribute certificates which evidence fractional shares of Common
Stock. In lieu of fractional shares of Common Stock, the Company shall pay to
the registered holders of Rights Certificates at the time such Rights are
exercised as herein provided an amount in cash equal to the same fraction of the
current market price of one (1) share of Common Stock (as determined pursuant to
Section 11(d)(i) hereof) for the Trading Day immediately prior to the date of
such exercise.

      (d) The holder of a Right by the acceptance of such Right expressly waives
his right to receive any fractional Rights or any fractional shares upon
exercise of a Right, except as permitted by this Section 14.

      Section 15. Rights of Action. All rights of action in respect of this
Agreement, except the rights of action expressly given to the Rights Agent in
Section 18 hereof, are vested in the respective registered holders of the Rights
Certificates (and, prior to the Distribution Date, the registered holders of the
Common Stock); and any registered holder of any Rights Certificate (or, prior to
the Distribution Date, of the Common Stock), without the consent of the Rights
Agent or of the holder of any other Rights Certificate (or, prior to the
Distribution Date, of the Common Stock), may, in his own behalf and for his own
benefit, enforce, and may institute and maintain any suit, action or proceeding
against the Company to enforce, or otherwise act in respect of, his right to
exercise the Rights evidenced by such Rights Certificate in the manner provided
in such Rights Certificate and in this Agreement. Without limiting the foregoing
or any remedies available to the holders of Rights, it is specifically
acknowledged that the holders of Rights would not have an adequate remedy at law
for any breach of this Agreement and shall be entitled

                                      -25-
<PAGE>

to specific performance of the obligations hereunder and injunctive relief
against actual or threatened violations of the obligations hereunder of any
Person subject to this Agreement.

      Section 16. Agreement of Rights Holders. Every holder of a Right by
accepting the same consents and agrees with the Company and the Rights Agent and
with every other holder of a Right that:

      (a) prior to the Distribution Date, the Rights will be transferable only
in connection with the transfer of Common Stock;

      (b) after the Distribution Date, the Rights Certificates are transferable
only on the registry books of the Rights Agent if surrendered at the office of
the Rights Agent designated for such purposes, duly endorsed or accompanied by a
proper instrument of transfer and with the appropriate forms and certificates
duly completed and fully executed;

      (c) subject to Section 6(a) and Section 7(f) hereof, the Company and the
Rights Agent may deem and treat the person in whose name a Rights Certificate
(or, prior to the Distribution Date, the associated Common Stock certificate) is
registered as the absolute owner thereof and of the Rights evidenced thereby
(notwithstanding any notations of ownership or writing on the Rights
Certificates or the associated Common Stock certificate made by anyone other
than the Company or the Rights Agent) for all purposes whatsoever, and neither
the Company nor the Rights Agent, subject to the penultimate sentence of Section
7(e) hereof, shall be required to be affected by any notice to the contrary; and

      (d) notwithstanding anything in this Agreement to the contrary, neither
the Company nor the Rights Agent shall have any liability to any holder of a
Right or other Person as a result of its inability to perform any of its
obligations under this Agreement by reason of any preliminary or permanent
injunction or other order, decree or ruling issued by a court of competent
jurisdiction or by a governmental, regulatory or administrative agency or
commission, or any statute, rule, regulation or executive order promulgated or
enacted by any governmental authority, prohibiting or otherwise restraining
performance of such obligation; provided, however, the Company must use its best
efforts to prevent the issuance of any such order, decree or ruling and to have
any such order, decree or ruling lifted or otherwise overturned as soon as
possible.

      Section 17. Rights Certificate Holder Not Deemed a Stockholder. No holder,
as such, of any Rights Certificate shall be entitled to vote, receive dividends
or be deemed for any purpose the holder of the number of one one-thousandths of
a share of Preferred Stock or any other securities of the Company which may at
any time be issuable on the exercise of the Rights represented thereby, nor
shall anything contained herein or in any Rights Certificate be construed to
confer upon the holder of any Rights Certificate, 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 Section 25 hereof),
or to receive dividends or subscription rights, or otherwise, until the Right or

                                      -26-
<PAGE>

Rights evidenced by such Rights Certificate shall have been exercised in
accordance with the provisions hereof.

      Section 18. Concerning the Rights Agent.

      (a) The Company agrees to pay to the Rights Agent reasonable compensation
for all services rendered by it hereunder and, from time to time, on demand of
the Rights Agent, its reasonable expenses and counsel fees and disbursements and
other disbursements incurred in the administration and execution of this
Agreement and the exercise and performance of its duties hereunder. The Company
also agrees to indemnify the Rights Agent for, and to hold it harmless against,
any loss, liability or expense, incurred without gross negligence, bad faith or
willful misconduct on the part of the Rights Agent, for anything done or omitted
by the Rights Agent in connection with the acceptance and administration of this
Agreement, including the costs and expenses of defending against any claim of
liability in the premises.

      (b) The Rights Agent shall be protected and shall incur no liability for
or in respect of any action taken, suffered or omitted by it in connection with
its administration of this Agreement in reliance upon any Rights Certificate or
certificate for Common Stock or for other securities of the Company, instrument
of assignment or transfer, power of attorney, endorsement, affidavit, letter,
notice, direction, consent, certificate, statement, or other paper or document
believed by it to be genuine and to be signed, executed and, where necessary,
verified or acknowledged, by the proper Person or Persons, or otherwise upon the
advice of counsel as set forth in Section 20 hereof.

      Section 19. Merger or Consolidation or Change of Name of Rights Agent.

      (a) Any corporation into which the Rights Agent or any successor Rights
Agent may be merged or with which it may be consolidated, or any corporation
resulting from any merger or consolidation to which the Rights Agent or any
successor Rights Agent shall be a party, or any corporation succeeding to the
corporate trust business of the Rights Agent or any successor Rights Agent,
shall be the successor to the Rights Agent under this Agreement without the
execution or filing of any paper or any further act on the part of any of the
parties hereto; provided, however, that such corporation would be eligible for
appointment as a successor Rights Agent under the provisions of Section 21
hereof. In case at the time such successor Rights Agent shall succeed to the
agency created by this Agreement, any of the Rights Certificates shall have been
countersigned but not delivered, any such successor Rights Agent may adopt the
countersignature of a predecessor Rights Agent and deliver such Rights
Certificates so countersigned; and in case at that time any of the Rights
Certificates shall not have been countersigned, any successor Rights Agent may
countersign such Rights Certificates either in the name of the predecessor or in
the name of the successor Rights Agent; and in all such cases such Rights
Certificates shall have the full force provided in the Rights Certificates and
in this Agreement.

      (b) In case at any time the name of the Rights Agent shall be changed and
at such time any of the Rights Certificates shall have been countersigned but
not delivered, the Rights Agent may adopt the countersignature under its prior
name and deliver Rights Certificates so

                                      -27-
<PAGE>

countersigned; and in case at that time any of the Rights Certificates shall not
have been countersigned, the Rights Agent may countersign such Rights
Certificates either in its prior name or in its changed name; and in all such
cases such Rights Certificates shall have the full force provided in the Rights
Certificates and in this Agreement.

      Section 20. Duties of Rights Agent. The Rights Agent undertakes the duties
and obligations imposed by this Agreement upon the following terms and
conditions, by all of which the Company and the holders of Rights Certificates,
by their acceptance thereof, shall be bound:

      (a) The Rights Agent may consult with legal counsel (who may be legal
counsel for the Company), and the opinion of such counsel shall be full and
complete authorization and protection to the Rights Agent as to any action taken
or omitted by it in good faith and in accordance with such opinion.

      (b) Whenever in the performance of its duties under this Agreement the
Rights Agent shall deem it necessary or desirable that any fact or matter
(including, without limitation, the identity of any Acquiring Person and the
determination of "current market price") be proved or established by the Company
prior to taking or suffering any action hereunder, such fact or matter (unless
other evidence in respect thereof be herein specifically prescribed) may be
deemed to be conclusively proved and established by a certificate signed by the
Chairman of the Board, the President, any Vice President, the Treasurer, any
Assistant Treasurer, the Secretary or any Assistant Secretary of the Company and
delivered to the Rights Agent; and such certificate shall be full authorization
to the Rights Agent for any action taken or suffered in good faith by it under
the provisions of this Agreement in reliance upon such certificate.

      (c) The Rights Agent shall be liable hereunder only for its own gross
negligence, bad faith or willful misconduct.

      (d) The Rights Agent shall not be liable for or by reason of any of the
statements of fact or recitals contained in this Agreement or in the Rights
Certificates or be required to verify the same (except as to its
countersignature on such Rights Certificates), but all such statements and
recitals are and shall be deemed to have been made by the Company only.

      (e) The Rights Agent shall not be under any responsibility in respect of
the validity of this Agreement or the execution and delivery hereof (except the
due execution hereof by the Rights Agent) or in respect of the validity or
execution of any Rights Certificate (except its countersignature thereof); nor
shall it be responsible for any breach by the Company of any covenant or
condition contained in this Agreement or in any Rights Certificate; nor shall it
be responsible for any adjustment required under the provisions of Section 11,
Section 13 or Section 24 hereof or responsible for the manner, method or amount
of any such adjustment or the ascertaining of the existence of facts that would
require any such adjustment (except with respect to the exercise of Rights
evidenced by Rights Certificates after receipt of a certificate describing any
such adjustment, delivered pursuant to Section 12); nor shall it by any act
hereunder be deemed to make any representation or warranty as to the
authorization or reservation of any shares of Common Stock or Preferred Stock to
be issued pursuant to this Agreement or any

                                      -28-
<PAGE>

Rights Certificate or as to whether any shares of Common Stock or Preferred
Stock will, when so issued, be validly authorized and issued, fully paid and
nonassessable.

      (f) The Company agrees that it will perform, execute, acknowledge and
deliver or cause to be performed, executed, acknowledged and delivered all such
further and other acts, instruments and assurances as may reasonably be required
by the Rights Agent for the carrying out or performing by the Rights Agent of
the provisions of this Agreement.

      (g) The Rights Agent is hereby authorized and directed to accept
instructions with respect to the performance of its duties hereunder from the
Chairman of the Board, the President, any Vice President, the Secretary, any
Assistant Secretary, the Treasurer or any Assistant Treasurer of the Company,
and to apply to such officers for advice or instructions in connection with its
duties, and it shall not be liable for any action taken or suffered to be taken
by it in good faith in accordance with instructions of any such officer. Any
application by the Rights Agent for written instructions from the Company may,
at the option of the Rights Agent, set forth in writing any action proposed to
be taken or omitted by the Rights Agent with respect to its duties or
obligations under this Rights Agreement and the date on and/or after which such
action shall be taken or omitted and the Rights Agent shall not be liable for
any action taken or omitted in accordance with a proposal included in any such
application on or after the date specified therein (which date shall not be less
than five Business Days after the date any such officer actually receives such
application, unless any such officer shall have consented in writing to an
earlier date) unless, prior to taking or omitting any such action, the Rights
Agent has received written instructions in response to such application
specifying the action to be taken or omitted.

      (h) The Rights Agent and any stockholder, director, officer or employee of
the Rights Agent may buy, sell or deal in any of the Rights or other securities
of the Company or become pecuniarily interested in any transaction in which the
Company may be interested, or contract with or lend money to the Company or
otherwise act as fully and freely as though it were not Rights Agent under this
Agreement. Nothing herein shall preclude the Rights Agent from acting in any
other capacity for the Company or for any other legal entity.

      (i) The Rights Agent may execute and exercise any of the rights or powers
hereby vested in it or perform any duty hereunder either itself or by or through
its attorneys or agents, and the Rights Agent shall not be answerable or
accountable for any act, default, neglect or misconduct of any such attorneys or
agents or for any loss to the Company resulting from any such act, default,
neglect or misconduct; provided, however, reasonable care was exercised in the
selection and continued employment thereof.

      (j) No provision of this Agreement shall require the Rights Agent to
expend or risk its own funds or otherwise incur any financial liability in the
performance of any of its duties hereunder or in the exercise of its rights if
there shall be reasonable grounds for believing that repayment of such funds or
adequate indemnification against such risk or liability is not reasonably
assured to it.

      (k) If, with respect to any Rights Certificate surrendered to the Rights
Agent for exercise or transfer, the certificate attached to the form of
assignment or form of election to

                                      -29-
<PAGE>

purchase, as the case may be, has not been completed, the Company and the Rights
Agent will deem the beneficial owner of the rights evidenced by such Rights
Certificate to be an Acquiring Person or an Affiliate or Associate thereof and
such assignment or election to purchase will not be honored.

      Section 21. Change of Rights Agent. The Rights Agent or any successor
Rights Agent may resign and be discharged from its duties under this Agreement
upon thirty (30) days' notice in writing mailed to the Company, and to each
transfer agent of the Common Stock and Preferred Stock, by registered or
certified mail, and to the holders of the Rights Certificates by first-class
mail. The Company may remove the Rights Agent or any successor Rights Agent upon
thirty (30) days' notice in writing, mailed to the Rights Agent or successor
Rights Agent, as the case may be, and to each transfer agent of the Common Stock
and Preferred Stock, by registered or certified mail, and to the holders of the
Rights Certificates by first-class mail. In the event the transfer agency
relationship in effect between the Company and the Rights Agent terminates, the
Rights Agent will be deemed to resign automatically on the effective date of
such termination, and any required notice will be sent by the Company. If the
Rights Agent shall resign or be removed or shall otherwise become incapable of
acting, the Company shall appoint a successor to the Rights Agent. If the
Company shall fail to make such appointment within a period of thirty (30) days
after giving notice of such removal or after it has been notified in writing of
such resignation or incapacity by the resigning or incapacitated Rights Agent or
by the holder of a Rights Certificate (who shall, with such notice, submit his
Rights Certificate for inspection by the Company), then any registered holder of
any Rights Certificate may apply to any court of competent jurisdiction for the
appointment of a new Rights Agent. Any successor Rights Agent, whether appointed
by the Company or by such a court, shall be (a) a corporation organized and
doing business under the laws of the United States (or of any state of the
United States) in good standing, which is authorized under such laws to exercise
corporate trust or stock transfer powers and is subject to supervision or
examination by federal or state authority and which has at the time of its
appointment as Rights Agent a combined capital and surplus of at least
$50,000,000 or (b) an affiliate of a corporation described in clause (a) of this
sentence. After appointment, the successor Rights Agent shall be vested with the
same powers, rights, duties and responsibilities as if it had been originally
named as Rights Agent without further act or deed; but the predecessor Rights
Agent shall deliver and transfer to the successor Rights Agent any property at
the time held by it hereunder, and execute and deliver any further assurance,
conveyance, act or deed necessary for the purpose. Not later than the effective
date of any such appointment, the Company shall file notice thereof in writing
with the predecessor Rights Agent and each transfer agent of the Common Stock
and the Preferred Stock, and mail a notice thereof in writing to the registered
holders of the Rights Certificates. Failure to give any notice provided for in
this Section 21, however, or any defect therein, shall not affect the legality
or validity of the resignation or removal of the Rights Agent or the appointment
of the successor Rights Agent, as the case may be.

      Section 22. Issuance of New Rights Certificates. Notwithstanding any of
the provisions of this Agreement or of the Rights to the contrary, the Company
may, at its option, issue new Rights Certificates evidencing Rights in such form
as may be approved by the Board to reflect any adjustment or change in the
Purchase Price and the number or kind or class of

                                      -30-
<PAGE>

shares or other securities or property purchasable under the Rights Certificates
made in accordance with the provisions of this Agreement.

      Section 23. Redemption; Independent Director Review.

      (a) The Board may, at its option, at any time prior to the earlier of (i)
the close of business on the tenth Business Day (or such later date as may be
determined by the Board pursuant to clause (i) of the first sentence of Section
3(a) with respect to the Distribution Date) following the Stock Acquisition Date
(or, if the Stock Acquisition Date shall have occurred prior to the Record Date,
the close of business on the tenth Business Day following the Record Date) and
(ii) the Final Expiration Date, redeem all but not less than all the then
outstanding Rights at a redemption price of $0.001 per Right, as such amount may
be appropriately adjusted to reflect any stock split, stock dividend or similar
transaction occurring after the date hereof (such redemption price being
hereinafter referred to as the "Redemption Price"). The redemption of the Rights
by the Board may be made effective at such time, on such basis and with such
conditions as the Board in its sole discretion may establish. The Company may,
at its option, pay the Redemption Price in cash, shares of Common Stock (based
on the "current market price," as defined in Section 11(d)(i) hereof, of the
Common Stock at the time of redemption) or any other form of consideration, or
any combination of any of the foregoing, deemed appropriate by the Board.
Notwithstanding anything contained in this Agreement to the contrary, the Rights
shall not be exercisable after the first occurrence of a Section 11(a)(ii) Event
until such time as the Company's right of redemption hereunder has expired.

      (b) Immediately upon the action of the Board ordering the redemption of
the Rights, evidence of which shall have been filed with the Rights Agent and
without any further action and without any notice, the right to exercise the
Rights shall terminate and the only right thereafter of the holders of Rights
shall be to receive the Redemption Price for each Right so held. Promptly after
the action of the Board ordering the redemption of the Rights, the Company shall
give notice of such redemption to the Rights Agent and the holders of the then
outstanding Rights by mailing such notice to all such holders at each holder's
last address as it appears upon the registry books of the Rights Agent or, prior
to the Distribution Date, on the registry books of the Transfer Agent for the
Common Stock. Any notice which is mailed in the manner herein provided shall be
deemed given, whether or not the holder receives the notice. Each such notice of
redemption will state the method by which the payment of the Redemption Price
will be made.

      (c) In the event of a redemption of the Rights in accordance with this
Agreement, the Company may, at its option, discharge all of its obligations with
respect to the Rights by (i) issuing a press release announcing the manner of
redemption of the Rights in accordance with this Agreement and (ii) mailing
payment of the Redemption Price to the registered holders of the Rights at their
last addresses as they appear on the registry books of the Rights Agent or,
prior to the Distribution Date, on the registry books of the Transfer Agent of
the Common Stock, and upon such action, all outstanding Rights and Right
Certificates shall be null and void without any further action by the Company.

                                      -31-
<PAGE>

      (d) At least once every three years, a committee of directors who are
independent of the management of the Company and free from any relationship
that, in the opinion of the board would interfere with their exercise of
independent judgment, shall review and evaluate this Rights Agreement in order
to consider whether the maintenance of this Rights Agreement continues to be in
the interests of the Company and its stockholders. Following each such review,
the committee will communicate its conclusions to the full Board, including any
recommendation in light thereof as to whether the Rights Agreement should be
modified or the Rights should be redeemed.

      Section 24. Exchange.

      (a) The Board may, at its option, at any time after a Section 11(a)(ii)
Event, exchange all or part of the then outstanding and exercisable Rights
(which (i) shall not include Rights that have become void pursuant to the
provisions of Section 7(e) hereof, and (ii) shall include, without limitation,
any Rights issued after the Distribution Date) for shares of Common Stock at an
exchange ratio of one share of Common Stock per Right, appropriately adjusted to
reflect any stock split, stock dividend or similar transaction occurring after
the date hereof (such exchange ratio being hereinafter referred to as the
"Exchange Ratio"). Notwithstanding the foregoing, the Board shall not be
empowered to effect such exchange at any time after any Person (other than the
Company, any Subsidiary of the Company, any employee benefit plan of the Company
or any such Subsidiary, or any entity holding Common Stock for or pursuant to
the terms of any such plan), together with all Affiliates and Associates of such
Person, becomes the Beneficial Owner of 50% or more of the shares of Common
Stock then outstanding.

      (b) Immediately upon the action of the Board ordering the exchange of any
Rights pursuant to subSection (a) of this Section 24, evidence of which shall
have been filed with the Rights Agent, and without any further action and
without any notice, the right to exercise such Rights shall terminate and the
only right thereafter of a holder of such Rights shall be to receive that number
of shares of Common Stock equal to the number of such Rights held by such holder
multiplied by the Exchange Ratio. The Company shall promptly give public notice
of any such exchange; provided, however, that the failure to give, or any defect
in, such notice shall not affect the validity of such exchange. The Company
promptly shall mail a notice of any such exchange to all of the holders of such
Rights at their last addresses as they appear upon the registry books of the
Rights Agent. Any notice which is mailed in the manner herein provided shall be
deemed given, whether or not the holder receives the notice. Each such notice of
exchange shall state the method by which the exchange of shares of Common Stock
for Rights will be effected and, in the event of any partial exchange, the
number of Rights which will be exchanged. Any partial exchange shall be effected
pro rata based on the number of Rights (other than Rights which have become void
pursuant to the provisions of Section 7(e) hereof) held by each holder of
Rights.

      (c) In any exchange pursuant to this Section 24, the Company, at its
option, may substitute Preferred Stock (or equivalent preferred stock, as such
term is defined in Section 11(b) hereof) for shares of Common Stock exchangeable
for Rights, at the initial rate of one one-thousandth of a share of Preferred
Stock (or equivalent preferred stock) for each share of Common Stock, as
appropriately adjusted to reflect adjustments in the voting rights of the

                                      -32-
<PAGE>

Preferred Stock pursuant to Section 3(A) of the Certificate of Designations
attached hereto as Exhibit A, so that the fraction of a share of Preferred Stock
(or equivalent preferred stock) delivered in lieu of each share of Common Stock
shall have the same voting rights as one share of Common Stock.

      (d) In the event that there shall not be sufficient shares of Common Stock
or Preferred Stock issued but not outstanding or authorized but unissued to
permit any exchange of Rights as contemplated in accordance with this Section
24, the Company shall take all such action as may be necessary to authorize
additional shares of Common Stock or Preferred Stock for issuance upon exchange
of the Rights.

      (e) The Company shall not be required to issue fractions of shares of
Common Stock or to distribute certificates which evidence fractional shares of
Common Stock. In lieu of such fractional shares of Common Stock, there shall be
paid to the registered holders of the Right Certificates with regard to which
such fractional shares of Common Stock would otherwise be issuable, an amount in
cash equal to the same fraction of the current market value of a whole share of
Common Stock. For the purposes of this subSection (e), the current market value
of a whole share of Common Stock shall be the closing price per share of Common
Stock (as determined pursuant to the second sentence of Section 11(d)(i) hereof)
for the Trading Day immediately prior to the date of exchange pursuant to this
Section 24.

      Section 25. Notice of Certain Events.

      (a) In case the Company shall propose, at any time after the Distribution
Date, (i) to pay any dividend payable in stock of any class to the holders of
Preferred Stock or to make any other distribution to the holders of Preferred
Stock (other than a regular quarterly cash dividend out of earnings or retained
earnings of the Company), or (ii) to offer to the holders of Preferred Stock
rights or warrants to subscribe for or to purchase any additional shares of
Preferred Stock or shares of stock of any class or any other securities, rights
or options, or (iii) to effect any reclassification of its Preferred Stock
(other than a reclassification involving only the subdivision of outstanding
shares of Preferred Stock), or (iv) to effect any consolidation or merger into
or with any other Person (other than a Subsidiary of the Company in a
transaction which complies with Section 11(o) hereof), or to effect any sale or
other transfer (or to permit one or more of its Subsidiaries to effect any sale
or other transfer), in one transaction or a series of related transactions, of
more than 50% of the assets or earning power of the Company and its Subsidiaries
(taken as a whole) to any other Person or Persons (other than the Company and/or
any of its Subsidiaries in one or more transactions each of which complies with
Section 11(o) hereof), or (v) to effect the liquidation, dissolution or winding
up of the Company, then, in each such case, the Company shall give to each
holder of a Rights Certificate, to the extent feasible and in accordance with
Section 26 hereof, a notice of such proposed action, which shall specify the
record date for the purposes of such stock dividend, distribution of rights or
warrants, or the date on which such reclassification, consolidation, merger,
sale, transfer, liquidation, dissolution, or winding up is to take place and the
date of participation therein by the holders of the shares of Preferred Stock,
if any such date is to be fixed, and such notice shall be so given in the case
of any action covered by clause (i) or (ii) above at least twenty (20) days
prior to the record date for determining holders of the shares of Preferred
Stock for purposes of such action, and in the case

                                      -33-
<PAGE>

of any such other action, at least twenty (20) days prior to the date of the
taking of such proposed action or the date of participation therein by the
holders of the shares of Preferred Stock, whichever shall be the earlier.

      (b) In case a Section 11(a)(ii) Event shall occur, then, in any such case,
(i) the Company shall as soon as practicable thereafter give to each holder of a
Rights Certificate, to the extent feasible and in accordance with Section 26
hereof, a notice of the occurrence of such event, which shall specify the event
and the consequences of the event to holders of Rights under Section 11(a)(ii)
hereof, and (ii) all references in the preceding paragraph to Preferred Stock
shall be deemed thereafter to refer also to Common Stock and/or, if appropriate,
other securities; provided that the failure to give such notice shall not affect
the validity of such consent.

      Section 26. Notices. Notices or demands authorized by this Agreement to be
given or made by the Rights Agent or by the holder of any Rights Certificate to
or on the Company shall be sufficiently given or made if sent by first-class
mail, postage prepaid, addressed (until another address is filed in writing with
the Rights Agent) as follows:

                      Alnylam Pharmaceuticals, Inc.
                      300 Third Street
                      Cambridge, MA 02142
                      Attention: Chief Executive Officer

                      with a copy to:

                      Wilmer Cutler Pickering Hale and Dorr LLP
                      60 State Street
                      Boston, MA 02109
                      Attention: Steven D. Singer, Esq.

Subject to the provisions of Section 21, any notice or demand authorized by this
Agreement to be given or made by the Company or by the holder of any Rights
Certificate to or on the Rights Agent shall be sufficiently given or made if
sent by first-class mail, postage prepaid, addressed (until another address is
filed in writing with the Company) as follows:

                      EquiServe Trust Company, N.A.
                      250 Royall Street
                      Canton, MA 02021
                      Attention:  Client Administration

Notices or demands authorized by this Agreement to be given or made by the
Company or the Rights Agent to the holder of any Rights Certificate (or, if
prior to the Distribution Date, to the holder of certificates representing
shares of Common Stock) shall be sufficiently given or made if sent by
first-class mail, postage prepaid, addressed to such holder at the address of
such holder as shown on the registry books of the Company.

                                      -34-
<PAGE>

      Section 27. Supplements and Amendments. Except as provided in the
penultimate sentence of this Section 27, for so long as the Rights are then
redeemable, the Company may, in its sole and absolute discretion, and the Rights
Agent shall, if the Company so directs, supplement or amend any provision of
this Agreement in any respect without the approval of any holders of the Rights.
At any time when the Rights are no longer redeemable, except as provided in the
penultimate sentence of this Section 27, the Company may, by approval of at
least 75% of the members of the Board, and the Rights Agent shall, if the
Company so directs, supplement or amend this Agreement without the approval of
any holders of Rights in order (i) to cure any ambiguity or (ii) to correct or
supplement any provision contained herein which may be defective or inconsistent
with any other provisions herein, provided that no such supplement or amendment
shall adversely affect the interests of the holders of Rights as such (other
than an Acquiring Person or an Affiliate or Associate of an Acquiring Person).
Upon the delivery of a certificate from an appropriate officer of the Company
which states that the proposed supplement or amendment is in compliance with the
terms of this Section 27, the Rights Agent shall execute such supplement or
amendment. Notwithstanding anything contained in this Agreement to the contrary,
no supplement or amendment shall be made which changes the Redemption Price.
Prior to the Distribution Date, the interests of the holders of Rights shall be
deemed coincident with the interests of the holders of Common Stock.

      Section 28. Successors. All the covenants and provisions of this Agreement
by or for the benefit of the Company or the Rights Agent shall bind and inure to
the benefit of their respective successors and assigns hereunder.

      Section 29. Actions by the Board, etc. The Board shall have the exclusive
power and authority to administer this Agreement and to exercise all rights and
powers specifically granted to the Board or to the Company, or as may be
necessary or advisable in the administration of this Agreement, including,
without limitation, the right and power to (i) interpret the provisions of this
Agreement, and (ii) make all determinations deemed necessary or advisable for
the administration of this Agreement (including a determination to redeem or not
redeem the Rights or to amend this Agreement). All such actions, calculations,
interpretations and determinations (including, for purposes of clause (y) below,
all omissions with respect to the foregoing) which are done or made by the Board
in good faith, shall (x) be final, conclusive and binding on the Company, the
Rights Agent, the holders of the Rights and all other parties, and (y) not
subject the Board to any liability to the holders of the Rights.

      Section 30. Benefits of this Agreement. Nothing in this Agreement shall be
construed to give to any Person other than the Company, the Rights Agent and the
registered holders of the Rights Certificates (and, prior to the Distribution
Date, registered holders of the Common Stock) any legal or equitable right,
remedy or claim under this Agreement; but this Agreement shall be for the sole
and exclusive benefit of the Company, the Rights Agent and the registered
holders of the Rights Certificates (and, prior to the Distribution Date,
registered holders of the Common Stock).

      Section 31. Severability. If any term, provision, covenant or restriction
of this Agreement is held by a court of competent jurisdiction or other
authority to be invalid, void or unenforceable, the remainder of the terms,
provisions, covenants and restrictions of this

                                      -35-
<PAGE>

Agreement shall remain in full force and effect and shall in no way be affected,
impaired or invalidated; provided, however, that notwithstanding anything in
this Agreement to the contrary, if any such term, provision, covenant or
restriction is held by such court or authority to be invalid, void or
unenforceable and the Board determines in its good faith judgment that severing
the invalid, void or unenforceable language from this Agreement would adversely
affect the purpose or effect of this Agreement, the right of redemption set
forth in Section 23 hereof shall be reinstated and shall not expire until the
close of business on the tenth day following the date of such determination by
the Board.

      Section 32. Governing Law. This Agreement, each Right and each Rights
Certificate issued hereunder shall be deemed to be a contract made under the
laws of the State of Delaware and for all purposes shall be governed by and
construed in accordance with the laws of Delaware applicable to contracts made
and to be performed entirely within Delaware.

      Section 33. Counterparts. This Agreement may be executed in any number of
counterparts and each of such counterparts shall for all purposes be deemed to
be an original, and all such counterparts shall together constitute but one and
the same instrument.

      Section 34. Descriptive Headings. Descriptive headings of the several
Sections of this Agreement are inserted for convenience only and shall not
control or affect the meaning or construction of any of the provisions hereof.

      Section 35. Force Majeure. Notwithstanding anything to the contrary
contained herein, the Rights Agent shall not be liable for any delays or
failures in performance resulting from acts beyond its reasonable control
including, without limitation, acts of God, terrorist acts, shortage of supply,
breakdowns or malfunctions, interruptions or malfunction of computer facilities,
or loss of data due to power failures or mechanical difficulties with
information storage or retrieval systems, labor difficulties, war, or civil
unrest.

                                      -36-
<PAGE>

      IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and their respective corporate seals to be hereunto affixed and
attested, all as of the day and year first above written.

Attest:                                      ALNYLAM PHARMACEUTICALS, INC.

By: /s/ Patricia L. Allen                    By: /s/ John M. Maraganore
    --------------------------------             -------------------------------
Name: Patricia L. Allen                      Name: John M. Maraganore
Title: VP, Finance                           Title: President and Chief
                                                      Executive Officer

Attest:                                      EQUISERVE TRUST COMPANY, N.A.

By: /s/ Monique Hughes                       By: /s/ Carol Mulvey-Eori
    --------------------------------             -------------------------------
Name: Monique Hughes                         Name: Carol Mulvey-Eori
Title: Account Manager                       Title: Managing Director

                                      -37-
<PAGE>

                                     FORM OF

                           CERTIFICATE OF DESIGNATIONS

                                       OF

                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

                                       OF

                          ALNYLAM PHARMACEUTICALS, INC.

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

Alnylam Pharmaceuticals, Inc., a corporation organized and existing under the
laws of the State of Delaware (hereinafter called the "Corporation"), hereby
certifies that the following resolution was adopted by the Board of Directors of
the Corporation at a meeting duly called and held on July 13, 2005:

RESOLVED: That pursuant to the authority granted to and vested in the Board of
Directors of the Corporation (hereinafter called the "Board") in accordance with
the provisions of the Certificate of Incorporation, as amended, the Board hereby
creates a series of Preferred Stock, $.01 par value per share (the "Preferred
Stock"), of the Corporation and hereby states the designation and number of
shares, and fixes the relative rights, preferences and limitations thereof as
follows:

      SERIES A JUNIOR PARTICIPATING PREFERRED STOCK:

      Section 1. Designation and Amount. The shares of such series shall be
designated as "Series A Junior Participating Preferred Stock" (the "Series A
Preferred Stock") and the number of shares constituting the Series A Preferred
Stock shall be one hundred twenty-five thousand (125,000). Such number of shares
may be increased or decreased by resolution of the Board prior to issuance;
provided, that no decrease shall reduce the number of shares of Series A
Preferred Stock to a number less than the number of shares then outstanding plus
the number of shares reserved for issuance upon the exercise of outstanding
options, rights or warrants or upon the conversion of any outstanding securities
issued by the Corporation convertible into Series A Preferred Stock.

      Section 2. Dividends and Distributions.

      (A) Subject to the rights of the holders of any shares of any series of
Preferred Stock (or any similar stock) ranking prior and superior to the Series
A Preferred Stock with respect to dividends, the holders of shares of Series A
Preferred Stock, in preference to the holders of Common Stock, par value $.01
per share (the "Common Stock"), of the Corporation, and of any other junior
stock, shall be entitled to receive, when, as and if declared by the Board out
of funds

                                      A-1
<PAGE>

of the Corporation legally available for the payment of dividends, quarterly
dividends payable in cash on the last day of each fiscal quarter of the
Corporation in each year (each such date being referred to herein as a
"Quarterly Dividend Payment Date"), commencing on the first Quarterly Dividend
Payment Date after the first issuance of a share or fraction of a share of
Series A Preferred Stock, in an amount per share (rounded to the nearest cent)
equal to the greater of (a) $10 or (b) subject to the provision for adjustment
hereinafter set forth, 1000 times the aggregate per share amount of all cash
dividends, and 1000 times the aggregate per share amount (payable in kind) of
all non-cash dividends or other distributions, other than a dividend payable in
shares of Common Stock or a subdivision of the outstanding shares of Common
Stock (by reclassification or otherwise), declared on the Common Stock since the
immediately preceding Quarterly Dividend Payment Date or, with respect to the
first Quarterly Dividend Payment Date, since the first issuance of any share or
fraction of a share of Series A Preferred Stock. In the event the Corporation
shall at any time declare or pay any dividend on the Common Stock payable in
shares of Common Stock, or effect a subdivision, combination or consolidation of
the outstanding shares of Common Stock (by reclassification or otherwise than by
payment of a dividend in shares of Common Stock) into a greater or lesser number
of shares of Common Stock, then in each such case the amount to which holders of
shares of Series A Preferred Stock were entitled immediately prior to such event
under clause (b) of the preceding sentence shall be adjusted by multiplying such
amount by a fraction, the numerator of which is the number of shares of Common
Stock outstanding immediately after such event and the denominator of which is
the number of shares of Common Stock that were outstanding immediately prior to
such event. In the event the Corporation shall at any time declare or pay any
dividend on the Series A Preferred Stock payable in shares of Series A Preferred
Stock, or effect a subdivision, combination or consolidation of the outstanding
shares of Series A Preferred Stock (by reclassification or otherwise than by
payment of a dividend in shares of Series A Preferred Stock) into a greater or
lesser number of shares of Series A Preferred Stock, then in each such case the
amount to which holders of shares of Series A Preferred Stock were entitled
immediately prior to such event under clause (b) of the first sentence of this
Section 2(A) shall be adjusted by multiplying such amount by a fraction, the
numerator of which is the number of shares of Series A Preferred Stock that were
outstanding immediately prior to such event and the denominator of which is the
number of shares of Series A Preferred Stock outstanding immediately after such
event.

      (B) The Corporation shall declare a dividend or distribution on the Series
A Preferred Stock as provided in paragraph (A) of this Section immediately after
it declares a dividend or distribution on the Common Stock (other than a
dividend payable in shares of Common Stock) and the Corporation shall pay such
dividend or distribution on the Series A Preferred Stock before the dividend or
distribution declared on the Common Stock is paid or set apart; provided that,
in the event no dividend or distribution shall have been declared on the Common
Stock during the period between any Quarterly Dividend Payment Date and the next
subsequent Quarterly Dividend Payment Date, a dividend of $10 per share on the
Series A Preferred Stock shall nevertheless be payable on such subsequent
Quarterly Dividend Payment Date.

      (C) Dividends shall begin to accrue and be cumulative on outstanding
shares of Series A Preferred Stock from the Quarterly Dividend Payment Date next
preceding the date of issue of such shares, unless the date of issue of such
shares is prior to the record date for the first

                                      A-2
<PAGE>

Quarterly Dividend Payment Date, in which case dividends on such shares shall
begin to accrue from the date of issue of such shares, or unless the date of
issue is a Quarterly Dividend Payment Date or is a date after the record date
for the determination of holders of shares of Series A Preferred Stock entitled
to receive a quarterly dividend and before such Quarterly Dividend Payment Date,
in either of which events such dividends shall begin to accrue and be cumulative
from such Quarterly Dividend Payment Date. Accrued but unpaid dividends shall
not bear interest. Dividends paid on the shares of Series A Preferred Stock in
an amount less than the total amount of such dividends at the time accrued and
payable on such shares shall be allocated pro rata on a share-by-share basis
among all such shares at the time outstanding. The Board may fix a record date
for the determination of holders of shares of Series A Preferred Stock entitled
to receive payment of a dividend or distribution declared thereon, which record
date shall be not more than 60 days prior to the date fixed for the payment
thereof.

      Section 3. Voting Rights. The holders of shares of Series A Preferred
Stock shall have the following voting rights:

      (A) Subject to the provision for adjustment hereinafter set forth, each
share of Series A Preferred Stock shall entitle the holder thereof to 1000 votes
on all matters submitted to a vote of the stockholders of the Corporation. In
the event the Corporation shall at any time declare or pay any dividend on the
Common Stock payable in shares of Common Stock, or effect a subdivision,
combination or consolidation of the outstanding shares of Common Stock (by
reclassification or otherwise than by payment of a dividend in shares of Common
Stock) into a greater or lesser number of shares of Common Stock, then in each
such case the number of votes per share to which holders of shares of Series A
Preferred Stock were entitled immediately prior to such event shall be adjusted
by multiplying such number by a fraction, the numerator of which is the number
of shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event. In the event the Corporation shall
at any time declare or pay any dividend on the Series A Preferred Stock payable
in shares of Series A Preferred Stock, or effect a subdivision, combination or
consolidation of the outstanding shares of Series A Preferred Stock (by
reclassification or otherwise than by payment of a dividend in shares of Series
A Preferred Stock) into a greater or lesser number of shares of Series A
Preferred Stock, then in each such case the number of votes per share to which
holders of shares of Series A Preferred Stock were entitled immediately prior to
such event shall be adjusted by multiplying such amount by a fraction, the
numerator of which is the number of shares of Series A Preferred Stock that were
outstanding immediately prior to such event and the denominator of which is the
number of shares of Series A Preferred Stock outstanding immediately after such
event.

      (B) Except as otherwise provided herein, in the Certificate of
Incorporation or by law, the holders of shares of Series A Preferred Stock and
the holders of shares of Common Stock and any other capital stock of the
Corporation having general voting rights shall vote together as one class on all
matters submitted to a vote of stockholders of the Corporation.

      (C) (i) If at any time dividends on any Series A Preferred Stock shall be
in arrears in an amount equal to six quarterly dividends thereon, the holders of
the Series A Preferred Stock, voting as a separate series from all other series
of Preferred Stock and classes of capital

                                      A-3
<PAGE>

stock, shall be entitled to elect two members of the Board in addition to any
Directors elected by any other series, class or classes of securities and the
authorized number of Directors will automatically be increased by two. Promptly
thereafter, the Board of the Corporation shall, as soon as may be practicable,
call a special meeting of holders of Series A Preferred Stock for the purpose of
electing such members of the Board. Such special meeting shall in any event be
held within 45 days of the occurrence of such arrearage.

            (ii) During any period when the holders of Series A Preferred Stock,
voting as a separate series, shall be entitled and shall have exercised their
right to elect two Directors, then, and during such time as such right
continues, (a) the then authorized number of Directors shall be increased by
two, and the holders of Series A Preferred Stock, voting as a separate series,
shall be entitled to elect the additional Directors so provided for, and (b)
each such additional Director shall not be a member of any existing class of the
Board, but shall serve until the next annual meeting of stockholders for the
election of Directors, or until his successor shall be elected and shall
qualify, or until his right to hold such office terminates pursuant to the
provisions of this Section 3(C).

            (iii) A Director elected pursuant to the terms hereof may be removed
with or without cause by the holders of Series A Preferred Stock entitled to
vote in an election of such Director.

            (iv) If, during any interval between annual meetings of stockholders
for the election of Directors and while the holders of Series A Preferred Stock
shall be entitled to elect two Directors, there is no such Director in office by
reason of resignation, death or removal, then, promptly thereafter, the Board
shall call a special meeting of the holders of Series A Preferred Stock for the
purpose of filling such vacancy and such vacancy shall be filled at such special
meeting. Such special meeting shall in any event be held within 45 days of the
occurrence of such vacancy.

            (v) At such time as the arrearage is fully cured, and all dividends
accumulated and unpaid on any shares of Series A Preferred Stock outstanding are
paid, and, in addition thereto, at least one regular dividend has been paid
subsequent to curing such arrearage, the term of office of any Director elected
pursuant to this Section 3(C), or his successor, shall automatically terminate,
and the authorized number of Directors shall automatically decrease by two, the
rights of the holders of the shares of the Series A Preferred Stock to vote as
provided in this Section 3(C) shall cease, subject to renewal from time to time
upon the same terms and conditions, and the holders of shares of the Series A
Preferred Stock shall have only the limited voting rights elsewhere herein set
forth.

      (D) Except as set forth herein, or as otherwise provided by law, holders
of Series A Preferred Stock shall have no special voting rights and their
consent shall not be required (except to the extent they are entitled to vote
with holders of Common Stock as set forth herein) for taking any corporate
action.

      Section 4. Certain Restrictions.

                                      A-4
<PAGE>

      (A) Whenever quarterly dividends or other dividends or distributions
payable on the Series A Preferred Stock as provided in Section 2 are in arrears,
thereafter and until all accrued and unpaid dividends and distributions, whether
or not declared, on shares of Series A Preferred Stock outstanding shall have
been paid in full, the Corporation shall not:

            (i) declare or pay dividends, or make any other distributions, on
any shares of stock ranking junior (either as to dividends or upon liquidation,
dissolution or winding up) to the Series A Preferred Stock;

            (ii) declare or pay dividends, or make any other distributions, on
any shares of stock ranking on a parity (either as to dividends or upon
liquidation, dissolution or winding up) with the Series A Preferred Stock,
except dividends paid ratably on the Series A Preferred Stock and all such
parity stock on which dividends are payable or in arrears in proportion to the
total amounts to which the holders of all such shares are then entitled;

            (iii) redeem or purchase or otherwise acquire for consideration
shares of any stock ranking junior (either as to dividends or upon liquidation,
dissolution or winding up) to the Series A Preferred Stock, provided that the
Corporation may at any time redeem, purchase or otherwise acquire shares of any
such junior stock in exchange for shares of any stock of the Corporation ranking
junior (either as to dividends or upon dissolution, liquidation or winding up)
to the Series A Preferred Stock; or

            (iv) redeem or purchase or otherwise acquire for consideration any
shares of Series A Preferred Stock, or any shares of stock ranking on a parity
with the Series A Preferred Stock, except in accordance with a purchase offer
made in writing or by publication (as determined by the Board) to all holders of
such shares upon such terms as the Board, after consideration of the respective
annual dividend rates and other relative rights and preferences of the
respective series and classes, shall determine in good faith will result in fair
and equitable treatment among the respective series or classes.

      (B) The Corporation shall not permit any subsidiary of the Corporation to
purchase or otherwise acquire for consideration any shares of stock of the
Corporation unless the Corporation could, under paragraph (A) of this Section 4,
purchase or otherwise acquire such shares at such time and in such manner.

      Section 5. Reacquired Shares. Any shares of Series A Preferred Stock
purchased or otherwise acquired by the Corporation in any manner whatsoever
shall be retired and cancelled promptly after the acquisition thereof. All such
shares shall upon their cancellation become authorized but unissued shares of
Preferred Stock and may be reissued as part of a new series of Preferred Stock
subject to the conditions and restrictions on issuance set forth herein, in the
Certificate of Incorporation, or in any other Certificate of Designations
creating a series of Preferred Stock or any similar stock or as otherwise
required by law.

      Section 6. Liquidation, Dissolution or Winding Up.

      (A) Upon any liquidation, dissolution or winding up of the Corporation, no
distribution shall be made (1) to the holders of shares of stock ranking junior
(either as to

                                      A-5
<PAGE>

dividends or upon liquidation, dissolution or winding up) to the Series A
Preferred Stock unless, prior thereto, the holders of shares of Series A
Preferred Stock shall have received $1000 per share, plus an amount equal to
accrued and unpaid dividends and distributions thereon, whether or not declared,
to the date of such payment, provided that the holders of shares of Series A
Preferred Stock shall be entitled to receive an aggregate amount per share,
subject to the provision for adjustment hereinafter set forth, equal to 1000
times the aggregate amount to be distributed per share to holders of shares of
Common Stock, or (2) to the holders of shares of stock ranking on a parity
(either as to dividends or upon liquidation, dissolution or winding up) with the
Series A Preferred Stock, except distributions made ratably on the Series A
Preferred Stock and all such parity stock in proportion to the total amounts to
which the holders of all such shares are entitled upon such liquidation,
dissolution or winding up.

      (B) Neither the consolidation, merger or other business combination of the
Corporation with or into any other corporation nor the sale, lease, exchange or
conveyance of all or any part of the property, assets or business of the
Corporation shall be deemed to be a liquidation, dissolution or winding up of
the Corporation for purposes of this Section 6.

      (C) In the event the Corporation shall at any time declare or pay any
dividend on the Common Stock payable in shares of Common Stock, or effect a
subdivision, combination or consolidation of the outstanding shares of Common
Stock (by reclassification or otherwise than by payment of a dividend in shares
of Common Stock) into a greater or lesser number of shares of Common Stock, then
in each such case the aggregate amount to which holders of shares of Series A
Preferred Stock were entitled immediately prior to such event under the proviso
in clause (1) of paragraph (A) of this Section 6 shall be adjusted by
multiplying such amount by a fraction, the numerator of which is the number of
shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event. In the event the Corporation shall
at any time declare or pay any dividend on the Series A Preferred Stock payable
in shares of Series A Preferred Stock, or effect a subdivision, combination or
consolidation of the outstanding shares of Series A Preferred Stock (by
reclassification or otherwise than by payment of a dividend in shares of Series
A Preferred Stock) into a greater or lesser number of shares of Series A
Preferred Stock, then in each such case the aggregate amount to which holders of
shares of Series A Preferred Stock were entitled immediately prior to such event
under the proviso in clause (1) of paragraph (A) of this Section 6 shall be
adjusted by multiplying such amount by a fraction, the numerator of which is the
number of shares of Series A Preferred Stock that were outstanding immediately
prior to such event and the denominator of which is the number of shares of
Series A Preferred Stock outstanding immediately after such event.

      Section 7. Consolidation, Merger, etc. Notwithstanding anything to the
contrary contained herein, in case the Corporation shall enter into any
consolidation, merger, combination or other transaction in which the shares of
Common Stock are exchanged for or changed into other stock or securities, cash
and/or any other property, then in any such case each share of Series A
Preferred Stock shall at the same time be similarly exchanged or changed into an
amount per share, subject to the provision for adjustment hereinafter set forth,
equal to 1,000 times the aggregate amount of stock, securities, cash and/or any
other property (payable in kind), as the case may be, into which or for which
each share of Common Stock is changed or

                                      A-6
<PAGE>

exchanged. In the event the Corporation shall at any time declare or pay any
dividend on the Common Stock payable in shares of Common Stock, or effect a
subdivision, combination or consolidation of the outstanding shares of Common
Stock (by reclassification or otherwise than by payment of a dividend in shares
of Common Stock) into a greater or lesser number of shares of Common Stock, then
in each such case the amount set forth in the preceding sentence with respect to
the exchange or change of shares of Series A Preferred Stock shall be adjusted
by multiplying such amount by a fraction, the numerator of which is the number
of shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event. In the event the Corporation shall
at any time declare or pay any dividend on the Series A Preferred Stock payable
in shares of Series A Preferred Stock, or effect a subdivision, combination or
consolidation of the outstanding shares of Series A Preferred Stock (by
reclassification or otherwise than by payment of a dividend in shares of Series
A Preferred Stock) into a greater or lesser number of shares of Series A
Preferred Stock, then in each such case the amount set forth in the first
sentence of this Section 7 with respect to the exchange or change of shares of
Series A Preferred Stock shall be adjusted by multiplying such amount by a
fraction, the numerator of which is the number of shares of Series A Preferred
Stock that were outstanding immediately prior to such event and the denominator
of which is the number of shares of Series A Preferred Stock outstanding
immediately after such event.

      Section 8. No Redemption. The shares of Series A Preferred Stock shall not
be redeemable.

      Section 9. Rank. The Series A Preferred Stock shall rank, with respect to
the payment of dividends and the distribution of assets, junior to all series of
any other class of the Preferred Stock issued either before or after the
issuance of the Series A Preferred Stock, unless the terms of any such series
shall provide otherwise.

      Section 10. Amendment. At such time as any shares of Series A Preferred
Stock are outstanding, the Certificate of Incorporation, as amended, of the
Corporation shall not be amended in any manner which would materially alter or
change the powers, preferences or special rights of the Series A Preferred Stock
so as to affect them adversely without the affirmative vote of the holders of at
least two-thirds of the outstanding shares of Series A Preferred Stock, voting
together as a single class.

      Section 11. Fractional Shares. Series A Preferred Stock may be issued in
fractions of a share which shall entitle the holder, in proportion to such
holder's fractional shares, to exercise voting rights, receive dividends,
participate in distributions and have the benefit of all other rights of holders
of Series A Preferred Stock.

                                      A-7
<PAGE>

      IN WITNESS WHEREOF, this Certificate of Designations is executed on behalf
of the Corporation by its Chief Executive Officer this 14th day of July, 2005.

                                  ALNYLAM PHARMACEUTICALS, INC.

                                  By: __________________________________________
                                  Name:  John M. Maraganore
                                  Title: President and Chief Executive Officer

                                      A-8
<PAGE>

                          [Form of Rights Certificate]

Certificate No. R-                                            ______ Rights

NOT EXERCISABLE AFTER JULY 13, 2015 OR EARLIER IF REDEEMED OR EXCHANGED BY THE
COMPANY. THE RIGHTS ARE SUBJECT TO REDEMPTION AT $.001 PER RIGHT AND TO EXCHANGE
ON THE TERMS SET FORTH IN THE RIGHTS AGREEMENT. UNDER CERTAIN CIRCUMSTANCES,
RIGHTS BENEFICIALLY OWNED BY AN ACQUIRING PERSON (AS SUCH TERM IS DEFINED IN THE
RIGHTS AGREEMENT) AND ANY SUBSEQUENT HOLDER OF SUCH RIGHTS MAY BECOME NULL AND
VOID. [THE RIGHTS REPRESENTED BY THIS RIGHTS CERTIFICATE ARE OR WERE
BENEFICIALLY OWNED BY A PERSON WHO WAS OR BECAME AN ACQUIRING PERSON OR AN
AFFILIATE OR ASSOCIATE OF AN ACQUIRING PERSON (AS SUCH TERMS ARE DEFINED IN THE
RIGHTS AGREEMENT). ACCORDINGLY, THIS RIGHTS CERTIFICATE AND THE RIGHTS
REPRESENTED HEREBY MAY BECOME NULL AND VOID IN THE CIRCUMSTANCES SPECIFIED IN
SECTION 7(e) OF SUCH AGREEMENT.](1)

                          ALNYLAM PHARMACEUTICALS, INC.

                               Rights Certificate

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 July 13, 2005 (the "Rights Agreement"), between Alnylam
Pharmaceuticals, Inc., a Delaware corporation (the "Company"), and EquiServe
Trust Company, N.A. (the "Rights Agent"), to purchase from the Company after the
Distribution Date (as such term is defined in the Rights Agreement) and at any
time prior to 5:00 p.m. (Boston time) on July 13, 2015 the office of the Rights
Agent designated for such purpose, or its successors as Rights Agent, one
one-thousandth of a fully paid, non-assessable share of Series A Junior
Participating Preferred Stock (the "Preferred Stock") of the Company, $.01 par
value per share, at a purchase price of $80 in cash per one one-thousandth of a
share (the "Purchase Price"), upon presentation and surrender of this Rights
Certificate with the Form of Election to Purchase and related Certificate duly
executed. The number of Rights evidenced by this Rights Certificate (and the
number of one one-thousandth of a share of Preferred Stock 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 the close of business on
July 26, 2005, based on the Preferred Stock as constituted at such date.
Capitalized terms used herein and not otherwise defined herein shall have the
meanings ascribed to such terms in the Rights Agreement.

Upon the occurrence of a Section 11(a)(ii) Event, if the Rights evidenced by
this Rights Certificate are beneficially owned by (i) an Acquiring Person or an
Affiliate or Associate of any

--------
(1) The portion of the legend in brackets shall be inserted only if applicable
and shall replace the preceding sentence.

                                      B-1
<PAGE>

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 an Acquiring Person, or (iii)
under certain circumstances specified in the Rights Agreement, a transferee of a
person who, concurrently with or after such transfer, became an Acquiring
Person, or an Affiliate or Associate of an Acquiring Person, such Rights shall
become null and void and no holder hereof shall have any right with respect to
such Rights from and after the occurrence of such Section 11(a)(ii) Event.

As provided in the Rights Agreement, the Purchase Price and the number and kind
of shares of Preferred Stock or other securities which may be purchased upon the
exercise of the Rights evidenced by this Rights Certificate are subject to
modification and adjustment upon the happening of certain events, including
Section 11(a)(ii) Events.

This Rights Certificate is subject to all of the terms, provisions and
conditions of the Rights Agreement, 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 Rights Certificates, which
limitations of rights include the temporary suspension of the exercisability of
such Rights under the specific circumstances set forth in the Rights Agreement.
Copies of the Rights Agreement are on file at the principal offices of the
Company and are available upon written request to the Company.

This Rights Certificate, with or without other Rights Certificates, upon
surrender at the office of the Rights Agent designated for such purpose, with
the Form of Election and Certificate set forth on the reverse side duly
executed, may be exchanged for another Rights Certificate or Rights Certificates
of like tenor and date evidencing Rights entitling the holder to purchase a like
aggregate number of one one-thousandths of a share of Preferred Stock as the
Rights evidenced by the Rights Certificate or Rights Certificates surrendered
shall have entitled such holder to purchase. If this Rights Certificate shall be
exercised in part, the holder shall be entitled to receive upon surrender hereof
another Rights Certificate or Rights Certificates for the number of whole Rights
not exercised.

Subject to the provisions of the Rights Agreement, the Rights evidenced by this
Certificate may be redeemed by the Company at its option at a redemption price
of $.001 per Right at any time prior to the earlier of (i) the close of business
on the tenth Business Day (or such later date as may be determined by the Board
pursuant to clause (i) of the first sentence of Section 3(a) with respect to the
Distribution Date) following the Stock Acquisition Date (or, if the Stock
Acquisition Date shall have occurred prior to the Record Date, the close of
business on the tenth Business Day following the Record Date) and (ii) the Final
Expiration Date.

Subject to the provisions of the Rights Agreement, the Company may, at its
option, at any time after a Section 11(a)(ii) Event, exchange all or part of the
Rights evidenced by this Certificate for shares of the Company's Common Stock or
for Preferred Stock (or shares of a class or series of the Company's preferred
stock having the same rights, privileges and preferences as the Preferred
Stock).

                                      B-2
<PAGE>

No fractional shares of Preferred Stock will be issued upon the exercise of any
Right or Rights evidenced hereby (other than fractions which are integral
multiples of one one-thousandth of a share of Preferred Stock, 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 Rights Certificate, as such, shall be entitled to vote or
receive dividends or be deemed for any purpose the holder of shares of Preferred
Stock 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 Rights
Certificate shall have been exercised as provided in the Rights Agreement.

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

      WITNESS the facsimile signature of the proper officers of the Company and
its corporate seal.

Dated as of _______________

ATTEST:                                   ALNYLAM PHARMACEUTICALS, INC.

                                          By: __________________________________
_____________________________________
Secretary                                 Title:  ______________________________

COUNTERSIGNED:

EQUISERVE TRUST COMPANY, N.A.

By: _________________________________

Authorized Signature

                                      B-3
<PAGE>

                  [Form of Reverse Side of Rights Certificate]

                               FORM OF ASSIGNMENT

                (To be executed by the registered holder if such

               holder desires to transfer the Rights Certificate.)

FOR VALUE RECEIVED _____________________________________________ hereby sells,
assigns and transfers unto _____________________________________________

_____________________________________________________________________

                  (Please print name and address of transferee)

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

Dated: ________________

                                                     ___________________________
                                                     Signature

Signature Guaranteed:

                                                    Certificate

The undersigned hereby certifies that the Rights evidenced by this Rights
Certificate are not beneficially owned by, or being assigned to, an Acquiring
Person or an Affiliate or Associate thereof (as such terms are defined pursuant
to the Rights Agreement).

Dated: ______________

                                                     ___________________________
                                                     Signature
Signature Guaranteed:

                                                    NOTICE

The signature to the foregoing Assignment and Certificate must correspond to the
name as written upon the face of this Rights Certificate in every particular,
without alteration or enlargement or any change whatsoever.

                                      B-4
<PAGE>

                          FORM OF ELECTION TO PURCHASE

                  (To be executed if holder desires to exercise

                 Rights represented by the Rights Certificate.)

To:  EquiServe Trust Company, N.A.

The undersigned hereby irrevocably elects to exercise ___________ Rights
represented by this Rights Certificate to purchase the shares of Preferred Stock
issuable upon the exercise of the Rights (or such other securities of the
Company or of any other person which may be issuable upon the exercise of the
Rights) and requests that certificates for such shares be issued in the name of
and delivered to:

Please insert social security

or other identifying number __________________________________________________

_____________________________________________________________________________

                         (Please print name and address)

_____________________________________________________________________________

If such number of Rights shall not be all the Rights evidenced by this Rights
Certificate, a new Rights Certificate for the balance 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)

_____________________________________________________________________________

Dated: ______________

                                                     ___________________________
                                                     Signature
Signature Guaranteed:

                                      B-5
<PAGE>

                                   Certificate

      The undersigned hereby certifies by checking the appropriate boxes that:

      (1) the Rights evidenced by this Rights Certificate [ ] are [ ] are not
being exercised by or on behalf of a Person who is or was an Acquiring Person or
an Affiliate or Associate thereof (as such terms are defined pursuant to the
Rights Agreement);

      (2) after due inquiry and to the best knowledge of the undersigned, the
undersigned [ ] did [ ] did not acquire the Rights evidenced by this Rights
Certificate from any Person who is, was or became an Acquiring Person or an
Affiliate or Associate thereof.

Dated: _______________

                                                     ___________________________
                                                     Signature
Signature Guaranteed:

                                                     NOTICE

The signature to the foregoing Election to Purchase and Certificate must
correspond to the name as written upon the face of this Rights Certificate in
every particular, without alteration or enlargement or any change whatsoever.

                                      B-6
<PAGE>

                              SUMMARY OF RIGHTS TO

                            PURCHASE PREFERRED STOCK

On July 13, 2005, the Board of Directors of Alnylam Pharmaceuticals, Inc. (the
"Company"), declared a dividend of one Right for each outstanding share of the
Company's Common Stock to stockholders of record at the close of business on
July 26, 2005 (the "Record Date"). Each Right entitles the registered holder to
purchase from the Company one one-thousandth of a share of Series A Junior
Participating Preferred Stock, $.01 par value per share (the "Preferred Stock"),
at a Purchase Price of $80 in cash, subject to adjustment. The description and
terms of the Rights are set forth in a Rights Agreement dated as of July 13,
2005 (the "Rights Agreement") between the Company and EquiServe Trust Company,
N.A., as Rights Agent.

Initially, the Rights are not exercisable and will be attached to all
certificates representing outstanding shares of Common Stock, and no separate
Rights Certificates will be distributed. The Rights will separate from the
Common Stock, and the Distribution Date will occur, upon the earlier of (i) 10
business days following the later of (a) the first date of a public announcement
that a person or group of affiliated or associated persons (an "Acquiring
Person") has acquired, or obtained the right to acquire, beneficial ownership of
20% or more of the outstanding shares of Common Stock or (b) the first date on
which an executive officer of the Company has actual knowledge that an Acquiring
Person has become such (the "Stock Acquisition Date") or (ii) 10 business days
following the commencement of a tender offer or exchange offer that would result
in a person or group beneficially owning 20% or more of the outstanding shares
of Common Stock. The Distribution Date may be deferred in circumstances
determined by the Board of Directors. In addition, certain inadvertent
acquisitions will not trigger the occurrence of the Distribution Date. Until the
Distribution Date (or earlier redemption or expiration of the Rights), (i) the
Rights will be evidenced by the Common Stock certificates outstanding on the
Record Date, together with this Summary of Rights, or by new Common Stock
certificates issued after the Record Date which contain a notation incorporating
the Rights Agreement by reference, (ii) the Rights will be transferred with and
only with such Common Stock certificates, and (iii) the surrender for transfer
of any certificates for Common Stock outstanding (with or without a copy of this
Summary of Rights or such notation) will also constitute the transfer of the
Rights associated with the Common Stock represented by such certificate.

The Rights are not exercisable until the Distribution Date and will expire upon
the close of business on July 13, 2015 (the "Final Expiration Date") unless
earlier redeemed or exchanged as described below. As soon as practicable after
the Distribution Date, separate Rights Certificates will be mailed to holders of
record of the Common Stock as of the close of business on the Distribution Date
and, thereafter, the separate Rights Certificates alone will represent the
Rights. Except as otherwise determined by the Board of Directors, and except for
shares of Common Stock issued upon exercise, conversion or exchange of then
outstanding options, convertible or exchangeable securities or other contingent
obligations to issue shares or pursuant to any employee benefit plan or
arrangement, only shares of Common Stock issued prior to the Distribution Date
will be issued with Rights.

                                      C-1
<PAGE>

In the event that any Person becomes an Acquiring Person, unless the event
causing the 20% threshold to be crossed is a Permitted Offer (as defined in the
Rights Agreement), then, promptly following the first occurrence of such event,
each holder of a Right (except as provided below and in Section 7(e) of the
Rights Agreement) shall thereafter have the right to receive, upon exercise,
that number of shares of Common Stock of the Company (or, in certain
circumstances, cash, property or other securities of the Company) which equals
the exercise price of the Right divided by 50% of the current market price (as
defined in the Rights Agreement) per share of Common Stock at the date of the
occurrence of such event. However, Rights are not exercisable following such
event until such time as the Rights are no longer redeemable by the Company as
described below. Notwithstanding any of the foregoing, following the occurrence
of such event, all Rights that are, or (under certain circumstances specified in
the Rights Agreement) were, beneficially owned by any Acquiring Person will be
null and void. The event summarized in this paragraph is referred to as a
"Section 11(a)(ii) Event."

For example, at an exercise price of $80 per Right, each Right not owned by an
Acquiring Person (or by certain related parties) following a Section 11(a)(ii)
Event would entitle its holder to purchase for $80 such number of shares of
Common Stock (or other consideration, as noted above) as equals $80 divided by
one-half of the current market price (as defined in the Rights Agreement) of the
Common Stock. Assuming that the Common Stock had a market price of $20 per share
at such time, the holder of each valid Right would be entitled to purchase eight
shares of Common Stock, having a market value of 8 x $20, or $160, for $80.

In the event that, at any time after any Person becomes an Acquiring Person, (i)
the Company is consolidated with, or merged with and into, another entity and
the Company is not the surviving entity of such consolidation or merger (other
than a consolidation or merger which follows a Permitted Offer) or if the
Company is the surviving entity, but shares of its outstanding Common Stock are
changed or exchanged for stock or securities (of any other person) or cash or
any other property, or (ii) more than 50% of the Company's assets or earning
power is sold or transferred, each holder of a Right (except Rights which
previously have been voided as set forth above) shall thereafter have the right
to receive, upon exercise, that number of shares of common stock of the
acquiring company which equals the exercise price of the Right divided by 50% of
the current market price (as defined in the Rights Agreement) of such common
stock at the date of the occurrence of the event. The events summarized in this
paragraph are referred to as "Section 13 Events." A Section 11(a)(ii) Event and
Section 13 Events are collectively referred to as "Triggering Events."

For example, at an exercise price of $80 per Right, each valid Right following a
Section 13 Event would entitle its holder to purchase for $80 such number of
shares of common stock of the acquiring company as equals $80 divided by
one-half of the current market price (as defined in the Rights Agreement) of
such common stock. Assuming that such common stock had a market price of $20 per
share at such time, the holder of each valid Right would be entitled to purchase
eight shares of common stock of the acquiring company, having a market value of
8 x $20, or $160, for $80.

At any time after the occurrence of a Section 11(a)(ii) Event, when no person
owns a majority of the Common Stock, the Board of Directors of the Company may
exchange the Rights (other than

                                      C-2
<PAGE>

Rights owned by such Acquiring Person which have become void), in whole or in
part, at an exchange ratio of one share of Common Stock, or one one-thousandth
of a share of Preferred Stock (or of a share of a class or series of the
Company's preferred stock having equivalent rights, preferences and privileges),
per Right (subject to adjustment).

The Purchase Price payable, and the number of units of Preferred Stock or other
securities or property issuable, upon exercise of the Rights are subject to
adjustment from time to time to prevent dilution (i) in the event of a stock
dividend on, or a subdivision, combination or reclassification of, the Preferred
Stock, (ii) if holders of the Preferred Stock are granted certain rights or
warrants to subscribe for Preferred Stock or convertible securities at less than
the then-current market price (as defined in the Rights Agreement) of the
Preferred Stock, or (iii) upon the distribution to holders of the Preferred
Stock of evidences of indebtedness or assets (excluding regular periodic cash
dividends paid out of earnings or retained earnings) or of subscription rights
or warrants (other than those referred to above). The number of Rights
associated with each share of Common Stock is also subject to adjustment in the
event of a stock split of the Common Stock or a stock dividend on the Common
Stock payable in Common Stock or subdivisions, consolidations or combinations of
the Common Stock occurring, in any such case, prior to the Distribution Date.

With certain exceptions, no adjustment in the Purchase Price will be required
until cumulative adjustments amount to at least 1% of the Purchase Price. No
fractional shares of Preferred Stock (other than fractions which are integral
multiples of one one-thousandth of a share of Preferred Stock) will be issued
and, in lieu thereof, an adjustment in cash will be made based on the market
price of the Preferred Stock on the last trading date prior to the date of
exercise.

Preferred Stock purchasable upon exercise of the Rights will not be redeemable.
Each share of Preferred Stock will be entitled to receive, when, as and if
declared by the Board of Directors, a minimum preferential quarterly dividend
payment of $10 per share or, if greater, an aggregate dividend of 1000 times the
dividend declared per share of Common Stock. In the event of liquidation, the
holders of the Preferred Stock will be entitled to a minimum preferential
liquidation payment of $1000 per share, plus an amount equal to accrued and
unpaid dividends, and will be entitled to an aggregate payment of 1000 times the
payment made per share of Common Stock. Each share of Preferred Stock will have
1000 votes, voting together with the Common Stock. In the event of any merger,
consolidation or other transaction in which Common Stock is changed or
exchanged, each share of Preferred Stock will be entitled to receive 1000 times
the amount received per share of Common Stock. These rights are protected by
customary antidilution provisions. Because of the nature of the Preferred
Stock's dividend, liquidation and voting rights, the value of one one-thousandth
of a share of Preferred Stock purchasable upon exercise of each Right should
approximate the value of one share of Common Stock.

At any time prior to the earlier of the tenth Business Day (or such later date
as may be determined by the Board of Directors of the Company) after the Stock
Acquisition Date, the Company may redeem the Rights in whole, but not in part,
at a price of $0.001 per Right (the "Redemption Price"), payable in cash or
stock. Immediately upon the redemption of the Rights or such earlier time as
established by the Board in the resolution ordering the redemption of the

                                      C-3
<PAGE>

Rights, the Rights will terminate and the only right of the holders of Rights
will be to receive the Redemption Price.

At least once every three years, a committee of independent directors will
evaluate the Rights Agreement in order to consider whether the maintenance of
the Rights Agreement continues to be in the interests of the Company and its
stockholders.

Until a Right is exercised, the holder thereof, as such, will have no rights as
a stockholder of the Company, including, without limitation, the right to vote
or to receive dividends. Although the distribution of the Rights should not be
taxable to stockholders or to the Company, stockholders may, depending upon the
circumstances, recognize taxable income in the event that the Rights become
exercisable for Common Stock (or other consideration) of the Company or for
common stock of the acquiring company as set forth above.

Any provision of the Rights Agreement, other than the redemption price, may be
amended by the Board prior to such time as the Rights are no longer redeemable.
Once the Rights are no longer redeemable, the Board's authority to amend the
Rights is limited to correcting ambiguities or defective or inconsistent
provisions in a manner that does not adversely affect the interest of holders of
Rights.

The Rights are intended to protect the stockholders of the Company in the event
of an unfair or coercive offer to acquire the Company and to provide the Board
with adequate time to evaluate unsolicited offers. The Rights may have
anti-takeover effects. The Rights will cause substantial dilution to a person or
group that attempts to acquire the Company without conditioning the offer on a
substantial number of Rights being acquired. The Rights, however, should not
affect any prospective offeror willing to make an offer at a fair price and
otherwise in the best interests of the Company and its stockholders, as
determined by the Board. The Rights should not interfere with any merger or
other business combination approved by the Board.

A copy of the Rights Agreement has been filed with the Securities and Exchange
Commission as an Exhibit to the Company's Current Report on Form 8-K dated July
14, 2005. A copy of the Rights Agreement is available free of charge from the
Company. This summary description of the Rights does not purport to be complete
and is qualified in its entirety by reference to the Rights Agreement, which is
incorporated herein by reference.

                                      C-4<PAGE>

                                                                   EXHIBIT 10.16

Date: 28th October 2002

PRIVATE & CONFIDENTIAL

Mr S Lewis
28 Mickleton Road
Earlsdon
Coventry
CV5 6PQ

Dear Steve,

Further to our recent discussions, I take pleasure in offering you a Temporary
International Assignment in the USA on accompanied status.

In addition, National Grid (USA) will provide employment for your accompanying
partner/spouse, Karen Manukonga, currently an employee of National Grid UK. With
minor exception, Karen's expatriate contract will mirror that of an accompanying
partner/spouse for as long as you remain on expatriate assignment and she
remains your partner/spouse.

If you accept this offer, with effect from 1st November 2002 you will take up
the position of VP and Head of Northeast Transmission Business for the National
Grid (USA) Inc in Westborough, USA. You will report to the Executive Vice
President and Chief Operating Officer National Grid (USA), currently Mike
Jesanis.

Your UK base salary will remain as (pound)80,000 gross pa. This gives a Net
Assignment Salary of (pound)71,687 per annum, other eligible benefits are as
indicated in the attached Temporary International Assignment Contract.

The Statement sets out your terms and conditions of employment. During your
assignment, your existing UK contract with the Company will be varied in
accordance with the Statement and the following documents:

      -     NGG International Assignment Policy document;

      -     Financial summary;

      -     Tax Equalisation Policy

      -     Code of Conduct.

For the duration of the assignment you and your accompanying partner/spouse will
be entitled to home leave return trips to the UK as set out in the NG policy
document. However, I am pleased to inform you that in recognition of your
forthcoming wedding you and your accompanying partner/spouse will be entitled to
an additional home leave return trip to the UK in 2003.

This offer is subject to the following conditions:

(i)   You and your partner holding valid passports

(ii)  The Company obtaining any necessary work and residency permit or other

<PAGE>

      appropriate visa from the host country for you and your accompanying
      partner

(iii) You and your accompanying partner consulting the Company's own medical
      adviser and a) being passed as fit for this assignment and b) receiving
      all inoculations/immunisations recommended by him [in accordance with good
      medical practice] for the area you are visiting. Any costs incurred in
      meeting any necessary medical requirements may be recovered from the
      Company.

If you have any questions regarding the temporary International Assignment
please let me know as soon as possible and I will do all I can to ensure they
are answered.

If you would like to accept this offer I should be grateful if you would sign
and return a copy of this letter as confirmation that you agree with the terms
of this offer by no later than 31st October 2002.

Yours sincerely

Maggie Hurt
Director of Human Resources

I accept the employment terms set out in this letter and the enclosed temporary
international assignment contract. I have also enclosed, duly signed by myself,
a copy of the contract signature acceptance sheet.

Signed: /s/ S. Lewis
Print Name Stephen P. Lewis
Dated: 29th October 2002

<PAGE>

                   TEMPORARY INTERNATIONAL ASSIGNMENT CONTRACT

THE NATIONAL GRID GROUP plc (the "Company") and THE NATIONAL GRID COMPANY plc
whose registered offices are at 15 Marylebone Road, London NW1 5JD and National
Grid House, Kirby Comer Road, Coventry, CV4 8JY respectively and

TO THE.EMPLOYEE: Stephen Lewis of 28 Mickleton Road, Earlsdon, Coventry, CV5
6PQ.

ON 21st October 2003

1.    Appointment and Term

1.1   You will be appointed to undertake a temporary overseas assignment VP and
      Head of Northeast Transmission Business for the National Grid (USA) Inc
      based in Westborough, USA. During the assignment you will report to the
      Executive Vice President and Chief Operating Office National Grid (USA),
      currently Mike Jesanis, who will discuss the precise nature of your duties
      and responsibilities with you. For all practical assignment issues covered
      in this contract you should refer to International Personnel Management
      Ltd (IPM), whom National Grid have appointed to undertake all expatriate
      administration. IPM can be contacted on +44 1733 352235.

1.2   This assignment and the provisions in this contract are effective from 1st
      November 2002. The assignment is expected to last for a period of 3 years,
      however, the Company may vary the duration of the contract if required.
      Any substantial alteration or variation to the length of the assignment
      will be by agreement and fully discussed with you before the changes are
      made.

1.3   This is an accompanied assignment. Your assignment terms and conditions as
      set out in this document have been prepared on that basis.

1.4   Throughout the period of your assignment the terms and conditions of your
      existing UK employment contract with the Company shall be varied in
      accordance with the terms and conditions placed on you while overseas as
      set out or referred to in this contract. But otherwise the terms and
      conditions of your existing UK employment contract shall continue to
      apply. At the expiration of this temporary international assignment
      contract, and subject to clause 10, you will return to the UK, and your
      existing UK employment contract will be modified to include any
      modifications made to the employment conditions of the Company's UK staff
      in the period of absence will become fully effective once again.

1.5   For the duration of your assignment John Carlton, Director of Network
      Strategy, will act in the role of mentor. This role will be to maintain
      regular professional contact with you during the assignment and to take
      managerial responsibility for your career management and repatriation.

2.    Hours of Work.

      The normal hours of work will be the same as those applying to local staff
      of the overseas company. However, you will be expected to work such other
      hours as may be

<PAGE>

      required for the proper performance of your duties and you will not be
      entitled to receive additional remuneration for work over and above normal
      hours.

3.    Pay

3.1   Salary

      3.1.1 During the assignment you will receive a salary equivalent to your
            Base Salary (specified in your Assignment Offer letter enclosed with
            this contract) net of Hypothetical Tax in accordance with the NG's
            International Tax Policy referred to in clause 7.

      3.1.2 In addition to your Base Salary, you will receive International
            Allowances as appropriate, which are calculated by reference to your
            Base Salary, and benefits, as set out below. These allowances will
            be paid to you without deducting hypothetical tax.

      3.1.3 Your Base Salary will be used to calculate your pension
            contributions throughout the period of your assignment in accordance
            with the NG's normal UK salary review policy.

3.2   Bonus

      For the duration of the assignment you will be eligible for a bonus. The
      maximum bonus you may earn is that percentage of your Base Salary set out
      in the attached financial summary based on achieving the performance
      targets agreed with Mike Jesanis. The amount of your bonus earned whilst
      on an international assignment will be subject to a hypothetical tax
      deduction at the time it is paid, as detailed in the International Tax
      Policy.

4.    International Allowances

      4.1   International and Cost of Living Allowances

            You are entitled to receive an international and cost of living
            allowances in accordance with NG's policy on your overseas location.
            Details of the allowances applicable to your assignment location are
            set out in the attached financial summary document. These allowances
            are paid to the individual monthly in arrears for the period of the
            assignment spent overseas in rented accommodation. The Company will
            be responsible for any taxes payable on these allowances.

      4.2   Disturbance Allowance

            4.2.1 A disturbance allowance of (pound)8,000 will be paid to you at
                  the start of your assignment, as set out in the attached
                  Financial Summary document. This amount will be made as a lump
                  sum upon you signing the contract.

<PAGE>

                  This is an accompanied level allowance to account for Karen
                  Manukonga, a National Grid employee, as your partner/spouse.

            4.2.2 This is intended to assist with the cost of settling into
                  overseas accommodation and in defraying the additional expense
                  incurred in moving away from the UK. The Company will be
                  responsible for any taxes payable on this allowance.

4.3   Terminal Bonus

      4.3.1 10% of your Base Salary per annum pro rata for the duration of the
            assignment will be paid to you as a one-off lump sum on completion
            of the assignment up to a maximum of three years. The Company will
            be responsible for any taxes payable on this bonus.

      4.3.2 No payment will be made if you terminate the assignment before the
            agreed term has been completed or if NG terminate the assignment in
            circumstances including gross misconduct by you or a serious or
            repeated breach by you of the Code of Conduct.

5.    Benefits

5.1   Accommodations/Utilities

      5.1.1 You will be responsible for determining arrangements for your UK
            home and all costs, taxes or other expenses related to your UK home
            are to your account.

      5.1.2 You may be required to spend a short period of time in hotel
            accommodation on arrival in the overseas location while furnished
            rented accommodation is secured. Details of NG's policy on temporary
            accommodation are set out in the NG policy document.

      5.1.3 NG will assist you in finding suitable fully furnished or
            unfurnished (as appropriate) accommodation in the overseas country.
            NG's policy on accommodation/rent allowance is set out in the NG
            policy document.

      5.1.4 The cost of reasonable utilities i.e. gas, water, electricity,
            telephone rental and business calls will be paid by NG in accordance
            with the NG policy document.

      5.1.5 You will remain responsible for obtaining appropriate Household
            Contents insurance as stated in the NG policy document.

5.2   Travel and Transport

      Air tickets to the destination at the start and end of the assignment will
      be provided for you and your partner/spouse. Details of NG's policy on
      flights, company cars and local transportation are set out in the NG
      policy document.

<PAGE>

5.3   Freight Allowances and Storage in the UK

      The Company will provide for the transportation of your personal baggage
      from the UK to the overseas country and subsequent return to the UK at the
      end of your assignment. Storage of some personal effects in the UK may be
      supported. Details of this policy are set out in the NG policy document.

5.4   Pension

      For the period of the assignment you will remain a member of the National
      Grid section of the Electricity Supply Pension Scheme. The Company will
      continue to make contributions and the appropriate deductions for your
      contributions will be made based on your Base salary.

5.5   Insurance

      Private international medical and dental insurance, including emergency
      repatriation, will be provided for you and your accompanying
      partner/spouse from the respective times of departure from your UK home to
      your destination and subsequent return. Further details of this general
      insurance coverage are set out in NG's policy document.

6.    Payment Arrangements

6.1   You should indicate the monthly amount in (pound) sterling, which you wish
      to be paid into a local bank account in the USA. This amount will be paid
      in local currency, calculated by reference to the exchange rate determined
      by our bankers in the UK on the day it is transferred. All transfer costs
      will be borne by the Company. The balance of your monthly salary will be
      paid into your nominated UK bank account in UK Sterling. Any changes to
      the location for payment should be made in line with NG's policy document.

6.2   The international and cost of living allowances ("the combined
      allowances") will be reviewed annually, currently in July. In this review
      the Company will take account of data provided by ECA International in
      respect of exchange rate movements, inflation and changes in any other
      appropriate measures. As a result of this review, the Company reserves the
      right to make changes to the amount of the combined allowances as
      appropriate. These changes will be implemented with immediate effect. You
      accept that your combined allowances may fluctuate up or down in July of
      each year and you accept that this fluctuation, if any, is in accordance
      with NG's policy as set out in the NG policy document.

7.    Taxation

7.1   The Company's approach to taxation is set out in the attached
      "International Tax" Policy.

7.2   In that you are on accompanied status with a National Grid employee, the
      Company may allocate shared non-salary benefits in kind for tax efficiency
      purposes.

8.    National Insurance Contributions

<PAGE>

8.1   NG will apply for the necessary certificate of coverage to exempt you from
      contributions to the Social Security Scheme.

8.2   In the unlikely event that any social security federal, state or local
      taxes equivalent to UK National Insurance Contributions become payable in
      the USA, the Company will reimburse you for those payments.

9.    Leave

9.1   Annual Leave: Your annual leave will remain unchanged from your total UK
      entitlement.

9.2   Public Holidays: During your assignment in the USA, UK fixed public
      holidays will be replaced by local public holidays. These days will be
      taken either as local holidays arise or as agreed with the Assignment
      Manager.

9.3   Home Leave: With effect from 1st November 2002 for the duration of the
      assignment you and your accompanying partner/spouse will be entitled to
      home leave return trips to the UK as set out in the NG policy document. In
      recognition of your forthcoming wedding you and your accompanying
      partner/spouse will be entitled to an additional home leave return trip to
      the UK in 2003.

10.   Termination

10.1  For the avoidance of doubt, the termination provisions in your existing UK
      contract will continue to apply notwithstanding your temporary assignment
      overseas.

10.2  Where possible, reasonable notice of any premature termination of
      assignment will always be given. However, the company reserves the right
      to terminate the Temporary Overseas Assignment at any time without
      indemnity, compensation or notice where NG deems it necessary or
      desirable. Non-exhaustive examples of reasons for termination are as
      follows:

      (a)   serious or repeated breach of the Code of Conduct;

      (b)   behaviour by you or accompanying partner/spouse in a manner which
            will bring you, the Company, or Overseas Company into disrepute;

      (c)   any change in the business need for the assignment or in the
            contractual/financial relationships supporting a particular project;

      (d)   if the company received advice that your continued employment in the
            USA would be likely to endanger your health or safety or that of
            accompanying partner/spouse.

10.3  Your return to the United Kingdom on premature termination or expiry of
      your assignment will be dealt with in accordance with Section 8.11 of the
      NG International Assignment Policy.

11.   Company Credit Card

      You will be issued with a company credit card to facilitate business
      expenditure abroad in accordance with NG's policy as set out in the NG
      policy document.

<PAGE>

12.   Financial

      You will be responsible for all financial obligations incurred by you
      during the term of your assignment, except where this expressly provides
      that the Company shall be liable for such expenses.

13.   Repatriation

      Prior to the end of your assignment, discussions will take place with NG
      Representatives to explore your skills, experience and aspirations as well
      as potential opportunities within National Grid Group to try to find you a
      suitable position within the Group, either in the UK, or elsewhere, as
      appropriate. Details of your repatriation are set out in the NG policy
      document.

14.   Jurisdiction

      Your assignment shall be governed by and all assignment documents shall be
      interpreted in accordance with the laws of England and Wales. All
      disputes, claims or proceedings between the parties relating to the
      validity, construction or performance of this Agreement are subject to the
      non-exclusive jurisdiction of the High Court of Justice in England and
      Wales.

Signed for and on behalf of The National Grid Company plc

Signed /s/ Maggie Hurt
Maggie Hurt
Director of Human Resources

Date 23.10.02

I have read the foregoing terms and conditions of employment and wish to accept
the temporary overseas assignment with the National Grid Group plc on those
terms and conditions.

Signed /s/ S Lewis
Stephen Lewis
Date 28.10.2002

<PAGE>

                                FINANCIAL SUMMARY

          YOUR ASSIGNMENT CONTRACT, EXCLUSIVE OF BENEFITS, IN THE FIRST
                   YEAR, IS WORTH APPROXIMATELY P 79,687

<TABLE>
<CAPTION>
             RENUMERATION                              ANNUAL
             ------------                              ------
<S>                                                 <C>
Assignment Salary
Base Salary                                         P 80,000.00
Deductions
Hypothetical Tax/PAYE                               P 25,409.84
SUB TOTAL                                           P 54,590.16
Assignment Allowances
International allowance                             P  8,000.00
Cost of living adjustment                           P  9,096.90
TOTAL RENUMERATION                                  P 71,687.06

TOTAL RENUMERATION (MONTHLY)                        P  5,973.92

Other Assignment Benefits:
Disturbance Allowance (tax free)                    P  8,000.00
One off payment at start of assignment

Bonuses
Performance
Potential to achieve a maximum of 25%
annual bonus, a notional tax of 40% will
be deducted from your bonus earned
whilst on assignment

Terminal
10% p.a. payable upon completion of this assignment
</TABLE>

These other benefits provide additional value and support to you and your
family:

Pre Assignment Visit
Cultural Briefing
Accommodation costs
Utility Costs
Removal costs
One return Business Class flight per annum to the UK for yourself and your
accompanying partner/spouse (or equivalent value in economy class tickets)
One additional flight to the UK for yourself and your accompanying
partner/spouse in 2003 for your wedding (this will be Economy Class)
Tax Assistance with tax returns for UK in the year of departure and return and
host country in each relevant year or part year
BUPA International Healthcare cover
Company Car/Transport Allowance
Assistance selling a privately owned car in the UK up to P 2,000 Two return
Economy flights per annum for each of your two dependent children to enable them
to visit you in the US

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