<PAGE>   1
                                                                   EXHIBIT 4





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

                            HARKEN ENERGY CORPORATION
                                       and
             CHASEMELLON SHAREHOLDER SERVICES L.L.C. as Rights Agent

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

                                RIGHTS AGREEMENT

                            Dated as of April 6, 1998

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





<PAGE>   2



                                TABLE OF CONTENTS
<TABLE>
<CAPTION>

                                                                                                      Page
                                                                                                      ----

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

Section 2.       Appointment of Rights Agent............................................................5

Section 3.       Issue of Right Certificates............................................................5

Section 4.       Form of Right Certificates.............................................................7

Section 5.       Countersignature and Registration......................................................7

Section 6.       Transfer, Split Up, Combination and Exchange of Right Certificates;
                 Mutilated, Destroyed, Lost or Stolen Right Certificates................................7

Section 7.       Exercise of Rights, Purchase Price; Expiration Date of Rights..........................8

Section 8.       Cancellation and Destruction of Right Certificates.....................................9

Section 9.       Availability of Shares of Preferred Stock..............................................9

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

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

Section 12.      Certificate of Adjusted Purchase Price or Number of Shares............................18

Section 13.      Consolidation, Merger or Sale or Transfer of Assets or Earning Power..................18

Section 14.      Fractional Rights and Fractional Shares...............................................21

Section 15.      Rights of Action......................................................................22

Section 16.      Agreement of Right Holders............................................................22

Section 17.      Right Certificate Holder Not Deemed a Stockholder.....................................23

Section 18.      Concerning the Rights Agent...........................................................23

Section 19.      Merger or Consolidation or Change of Name of Rights Agent.............................24

Section 20.      Duties of Rights Agent................................................................24
</TABLE>

                                        i

<PAGE>   3

<TABLE>


<S>               <C>                                                                                   <C>
Section 21.       Change of Rights Agent................................................................26

Section 22.       Issuance of New Right Certificates....................................................27

Section 23.       Redemption............................................................................27

Section 24.       Exchange..............................................................................28

Section 25.       Notice of Certain Events..............................................................29

Section 26.       Notices...............................................................................29

Section 27.       Supplements and Amendments............................................................30

Section 28.       Successors............................................................................30

Section 29.       Benefits of this Agreement............................................................30

Section 30.       Determinations and Actions by the Board of Directors..................................30

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

Section 32.       Governing Law.........................................................................31

Section 33.       Counterparts..........................................................................31

Section 34.       Descriptive Headings..................................................................31

Section 35.       Termination...........................................................................31
</TABLE>



                                       ii

<PAGE>   4



                                RIGHTS AGREEMENT


                  Rights Agreement, dated as of April 6, 1998 ("Agreement"),
between Harken Energy Corporation, a Delaware corporation (the "Company"), and
ChaseMellon Shareholder Services L.L.C., as Rights Agent (the "Rights Agent").

                  The Board of Directors of the Company has authorized and
declared a dividend of one preferred share purchase right (a "Right") for each
share of Common Stock (as hereinafter defined) of the Company outstanding as of
the Close of Business (as defined below) on April 17, 1998 (the "Record Date"),
each Right representing the right to purchase one one-thousandth (subject to
adjustment) of a share of Preferred Stock (as hereinafter defined), upon the
terms and subject to the conditions herein set forth, and has further authorized
and directed the issuance of one Right (subject to adjustment as provided
herein) with respect to each share of Common Stock that shall become outstanding
between the Record Date and the earlier of the Distribution Date and the
Expiration Date (as such terms are hereinafter defined); provided, however, that
Rights may be issued with respect to shares of Common Stock that shall become
outstanding after the Distribution Date and prior to the Expiration Date in
accordance with Section 22.

                  Accordingly, 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 meaning indicated:

                  (a) "Acquiring Person" shall mean any Person (as such term is
hereinafter defined) who or which shall be the Beneficial Owner (as such term is
hereinafter defined) of 15% or more of the shares of Common Stock then
outstanding, but shall not include an Exempt Person (as such term is hereinafter
defined); provided, however, that (i) if the Board of Directors of the Company
determines in good faith that a Person who would otherwise be an "Acquiring
Person" became such inadvertently (including, without limitation, because (A)
such Person was unaware that it beneficially owned a percentage of Common Stock
that would otherwise cause such Person to be an "Acquiring Person" or (B) such
Person was aware of the extent of its Beneficial Ownership of Common Stock but
had no actual knowledge of the consequences of such Beneficial Ownership under
this Agreement) and without any intention of changing or influencing control of
the Company, and if such Person as promptly as practicable divested or divests
itself of Beneficial Ownership of a sufficient number of shares of Common Stock
so that such Person would no longer be an "Acquiring Person," then such Person
shall not be deemed to be or to have become an "Acquiring Person" for any
purposes of this Agreement; (ii) if, as of the date hereof, any Person is the
Beneficial Owner of 15% or more but less than 20% of the shares of Common Stock
outstanding, such Person shall not be or become an "Acquiring Person" unless and
until such time as such Person shall become the Beneficial Owner of additional
shares of Common Stock (other than pursuant to a dividend or distribution paid
or made by the Company on the outstanding Common Stock in shares of Common Stock
or pursuant to a split or subdivision of the outstanding Common Stock), unless,
upon becoming the Beneficial Owner of such additional shares of Common Stock,
such Person is not then the Beneficial Owner of 15% or more of the shares of
Common Stock then outstanding; and


<PAGE>   5


(iii) no Person shall become an "Acquiring Person" as the result of an
acquisition of shares of Common Stock by the Company which, by reducing the
number of shares outstanding, increases the proportionate number of shares of
Common Stock beneficially owned by such Person to 15% or more of the shares of
Common Stock then outstanding, provided, however, that if a Person shall become
the Beneficial Owner of 15% or more of the shares of Common Stock then
outstanding by reason of such share acquisitions by the Company and shall
thereafter become the Beneficial Owner of any additional shares of Common Stock
(other than pursuant to a dividend or distribution paid or made by the Company
on the outstanding Common Stock in shares of Common Stock or pursuant to a split
or subdivision of the outstanding Common Stock), then such Person shall be
deemed to be an "Acquiring Person" unless upon becoming the Beneficial Owner of
such additional shares of Common Stock such Person does not beneficially own 15%
or more of the shares of Common Stock then outstanding. 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)(1)(i) of the General Rules and Regulations under the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), as in effect on the date
hereof.

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

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

                           (i)      which such Person or any of such Person's
Affiliates or Associates is deemed to beneficially own, directly or indirectly,
within the meaning of Rule l3d-3 of the General Rules and Regulations under the
Exchange Act as in effect on the date hereof;

                           (ii)     which such Person or any of such Person's 
Affiliates or Associates has (A) 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 upon the exercise of conversion rights,
exchange rights, rights, warrants or options, or otherwise; provided, however,
that a Person shall not be deemed the Beneficial Owner of, or to beneficially
own, (x) 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, (y) securities which such
Person has a right to acquire upon the exercise of Rights at any time prior to
the time that any Person becomes an Acquiring Person or (z) securities issuable
upon the exercise of Rights from and after the time that any Person becomes an
Acquiring Person if such 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 ("Original Rights") or pursuant to Section
11(i) or Section 11(n) with respect to an adjustment to Original Rights; or (B)
the right to vote pursuant to any agreement, arrangement or understanding;
provided, however, that a Person shall not be deemed the Beneficial Owner of, or
to beneficially own, any security by reason of such agreement, arrangement or
understanding if the agreement, arrangement or




                                       2
<PAGE>   6


understanding to vote such security (1) arises solely from a revocable proxy or
consent given to such Person in response to a public proxy or consent
solicitation made pursuant to, and in accordance with, the applicable rules and
regulations promulgated under the Exchange Act and (2) is not also then
reportable 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 and with respect to 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)
for the purpose of acquiring, holding, voting (except to the extent contemplated
by the proviso to Section 1(c)(ii)(B)) or disposing of such securities of the
Company; provided, however, that no Person who is an officer, director or
employee of an Exempt Person shall be deemed, solely by reason of such Person's
status or authority as such, to be the "Beneficial Owner" of, to have
"Beneficial Ownership" of or to "beneficially own" any securities that are
"beneficially owned" (as defined in this Section l(c)), including, without
limitation, in a fiduciary capacity, by an Exempt Person or by any other such
officer, director or employee of an Exempt Person.

                  (d)      "Business Day" shall mean any day other than a
Saturday, a Sunday or a day on which banking institutions in the State of New
York or the city in which the principal office of the Rights Agent is located
are authorized or obligated by law or executive order to close.

                  (e)      "Close of Business" on any given date shall mean 5:00
P.M., New York City time, on such date; provided, however, that if such date is
not a Business Day it shall mean 5:00 P.M., New York City time, on the next
succeeding Business Day.

                  (f)      "Common Stock" when used with reference to the
Company shall mean the Common Stock, presently par value $.01 per share, of the
Company. "Common Stock" when used with reference to any Person other than the
Company shall mean the common stock (or, in the case of an unincorporated
entity, the equivalent equity interest) with the greatest voting power of such
other Person or, if such other Person is a subsidiary of another Person, the
Person or Persons which ultimately control such first-mentioned Person.

                  (g)      "Common Stock Equivalents" shall have the meaning set
forth in Section 11(a)(iii) hereof.

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

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

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

                  (k)      "Exempt Person" shall mean the Company or any 
Subsidiary (as such term is hereinafter defined) of the Company, in each case
including, without limitation, in its fiduciary capacity, or any employee
benefit plan of the Company or of any Subsidiary of the Company, or any 



                                        3

<PAGE>   7




entity or trustee holding Common Stock for or pursuant to the terms of any such
plan or for the purpose of funding any such plan or funding other employee
benefits for employees of the Company or of any Subsidiary of the Company.

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

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

                  (n)      "Flip-In Event" shall have the meaning set forth in
Section 11(a)(ii) hereof.

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

                  (p)      "NASDAQ" shall mean the National Association of
Securities Dealers, Inc. Automated Quotation System.

                  (q)      "New York Stock Exchange" shall mean the New York 
Stock Exchange, Inc.

                  (r)      "Person" shall mean any individual, firm, 
corporation, partnership, limited liability company, trust or other entity, and
shall include any successor (by merger or otherwise) to such entity.

                  (s)      "Preferred Stock" shall mean the Series E Junior
Participating Preferred Stock, par value $1.00 per share, of the Company having
the rights and preferences set forth in the Form of Certificate of Designation
attached to this Agreement as Exhibit A.

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

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

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

                  (w)      "Right Certificate" shall have the meaning set forth
in Section 3 hereof.

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

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

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

                  (aa)     "Stock Acquisition Date" shall mean the first date of
public announcement (which, for purposes of this definition, shall include,
without limitation, a report filed pursuant to Section 13(d) of the Exchange
Act) by the Company or an Acquiring Person that an Acquiring Person has become
such, or such earlier date as a majority of the Board of Directors shall become
aware of the existence of an Acquiring Person.


                                        4

<PAGE>   8



                  (bb)     "Subsidiary" of any Person shall mean any corporation
or other entity of which securities or other ownership interests having ordinary
voting power sufficient to elect a majority of the board of directors or other
persons performing similar functions are beneficially owned, directly or
indirectly, by such Person, and any corporation or other entity that is
otherwise controlled by such Person.

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

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

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

                  Section 2.    Appointment of Rights Agent. The Company hereby
appoints the Rights Agent to act as agent for the Company 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.

                  Section 3.    Issue of Right Certificates.

                  (a)      Until the Close of Business on the earlier of (i) the
tenth day after the Stock Acquisition Date or (ii) the tenth Business Day (or
such later date as may be determined by action of the Board of Directors prior
to such time as any Person becomes an Acquiring Person) after the date of the
commencement by any Person (other than an Exempt Person) of, or of the first
public announcement of the intention of such Person (other than an Exempt
Person) to commence, a tender or exchange offer the consummation of which would
result in any Person (other than an Exempt Person) becoming the Beneficial Owner
of shares of Common Stock aggregating 15% or more of the Common Stock then
outstanding (the earlier of such dates being herein referred to as the
"Distribution Date"; provided, however, that if either of such dates occurs
after the date of this Agreement and on or prior to the Record Date, then the
Distribution Date shall be the Record Date), (x) the Rights will be evidenced
(subject to the provisions of Section 3(b) hereof) by the certificates for
Common Stock registered in the names of the holders thereof and not by separate
Right Certificates, and (y) the Rights will be transferable only in connection
with the transfer of Common Stock. As soon as practicable after the Distribution
Date, the Company will prepare and execute, the Rights Agent will countersign
and the Company will send or cause to be sent (and the Rights Agent will, if
requested, send) by first-class, insured, postage-prepaid mail, to each record
holder of Common Stock as of the close of business on the Distribution Date
(other than any Acquiring Person or any Associate or Affiliate of an Acquiring
Person), at the address of such holder shown on the records of the Company, a
Right Certificate, in substantially the form of Exhibit B hereto (a "Right
Certificate"), evidencing one Right (subject to adjustment as provided herein)
for each share of Common Stock so held. As of the Distribution Date, the Rights
will be evidenced solely by such Right Certificates.

                  (b)      On the Record Date, or as soon as practicable 
thereafter, the Company will send a copy of a Summary of Rights to Purchase
Shares of Preferred Stock, in substantially the form of Exhibit C hereto (the
"Summary of Rights"), by first-class, postage-prepaid mail, to each record

                                        5

<PAGE>   9



holder of Common Stock as of the Close of Business on the Record Date (other
than any Acquiring Person or any Associate or Affiliate of any Acquiring
Person), at the address of such holder shown on the records of the Company. With
respect to certificates for Common Stock outstanding as of the Record Date,
until the Distribution Date, the Rights will be evidenced by such certificates
registered in the names of the holders thereof together with the Summary of
Rights. Until the Distribution Date (or, if earlier, the Expiration Date), the
surrender for transfer of any certificate for Common Stock outstanding on the
Record Date, with or without a copy of the Summary of Rights, shall also
constitute the transfer of the Rights associated with the Common Stock
represented thereby.

                  (c)      Certificates issued for Common Stock (including, 
without limitation, upon transfer of outstanding Common Stock, disposition of
Common Stock out of treasury stock or issuance or reissuance of Common Stock out
of authorized but unissued shares) after the Record Date but prior to the
earlier of the Distribution Date and the Expiration Date shall have impressed
on, printed on, written on or otherwise affixed to them the following legend:

                  This certificate also evidences and entitles the
                  holder hereof to certain rights as set forth in a
                  Rights Agreement between Harken Energy Corporation
                  (the "Company") and ChaseMellon Shareholder Services
                  L.L.C., as Rights Agent, dated as of April 6, 1998
                  as the same may be amended 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 executive 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 without charge after receipt
                  of a written request therefor. Under certain
                  circumstances, as set forth in the Rights Agreement,
                  Rights owned by or transferred to any Person who is
                  or becomes an Acquiring Person (as defined in the
                  Rights Agreement) and certain transferees thereof
                  will become null and void and will no longer be
                  transferable.

With respect to such certificates containing the foregoing legend, until the
Distribution Date the Rights associated with the Common Stock represented by
such certificates shall be evidenced by such certificates alone, and the
surrender for transfer of any such certificate, except as otherwise provided
herein, shall also constitute the transfer of the Rights associated with the
Common Stock represented thereby. In the event that the Company purchases or
otherwise acquires any Common Stock after the Record Date but prior to the
Distribution Date, any Rights associated with such Common Stock shall be deemed
canceled and retired so that the Company shall not be entitled to exercise any
Rights associated with the Common Stock which are no longer outstanding.

                  Notwithstanding this paragraph (c), the omission of a legend
shall not affect the enforceability of any part of this Agreement or the rights
of any holder of the Rights.


                                        6

<PAGE>   10



                  Section 4.    Form of Right Certificates. The Right
Certificates (and the forms of election to purchase shares and of assignment to
be printed on the reverse thereof) shall 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 interdealer quotation system on which the Rights may from time to
time be listed or quoted, or to conform to usage. Subject to the provisions of
Sections 11, 13 and 22 hereof, the Right Certificates 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 per one one-thousandth of a
share of Preferred Stock set forth therein (the "Purchase Price"), but the
number of such one one-thousandths of a share of Preferred Stock and the
Purchase Price shall be subject to adjustment as provided herein.

                  Section 5.    Countersignature and Registration.

                  (a)      The Right Certificates shall be executed on behalf of
the Company by the President of the Company, either manually or by facsimile
signature, shall have affixed thereto the Company's seal or a facsimile thereof
and shall be attested by the Secretary of the Company, either manually or by
facsimile signature. The Right Certificates shall be manually countersigned by
the Rights Agent and shall not be valid for any purpose unless countersigned. In
case any officer of the Company who shall have signed any of the Right
Certificates shall cease to be such officer of the Company before
countersignature by the Rights Agent and issuance and delivery by the Company,
such Right 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 Right Certificates had not ceased to be such officer
of the Company; and any Right Certificate may be signed on behalf of the Company
by any Person who, at the actual date of the execution of such Right
Certificate, shall be a proper officer of the Company to sign such Right
Certificate, although at the date of the execution of this Agreement any such
Person was not such an officer.

                  (b)      Following the Distribution Date, the Rights Agent 
will keep or cause to be kept, at an office or agency designated for such
purpose, books for registration and transfer of the Right Certificates issued
hereunder. Such books shall show the names and addresses of the respective
holders of the Right Certificates, the number of Rights evidenced on its face by
each of the Right Certificates and the date of each of the Right Certificates.

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

                  (a)      Subject to the provisions of Sections 7(e), 11(a)
(ii), 13 and 14 hereof, at any time after the Distribution Date and prior to the
Expiration Date, any Right Certificate or Right Certificates may be transferred,
split up, combined or exchanged for another Right Certificate or Right
Certificates, entitling the registered holder to purchase a like number of one
one-thousandths of a share of Preferred Stock as the Right Certificate or Right
Certificates surrendered then entitled such holder to purchase. Any registered
holder desiring to transfer, split up, combine or exchange any Right Certificate
or Right Certificates shall make such request in writing delivered to the Rights


                                       7

<PAGE>   11

Agent, and shall surrender the Right Certificate or Right Certificates to be
transferred, split up, combined or exchanged at the office or agency of the
Rights Agent designated for such purpose. Thereupon the Rights Agent shall
countersign and deliver to the Person entitled thereto a Right Certificate or
Right 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
Right Certificates.

                  (b)      Subject to the provisions of Section 11(a)(ii) 
hereof, at any time after the Distribution Date and prior to the Expiration
Date, upon receipt by the Company and the Rights Agent of evidence reasonably
satisfactory to them of the loss, theft, destruction or mutilation of a Right
Certificate, and, in case of loss, theft or destruction of indemnity or security
reasonably satisfactory to them, and, at the Company's request, 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 Right Certificate
if mutilated, the Company will make and deliver a new Right Certificate of like
tenor to the Rights Agent for delivery to the registered holder in lieu of the
Right Certificate so lost, stolen, destroyed or mutilated.

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

                  (a)      Except as otherwise provided herein, the Rights shall
become exercisable on the Distribution Date, and thereafter the registered
holder of any Right Certificate may, subject to Section 11(a)(ii) hereof and
except as otherwise provided herein, exercise the Rights evidenced thereby in
whole or in part upon surrender of the Right Certificate, with the form of
election to purchase on the reverse side thereof duly executed, to the Rights
Agent at the office or agency 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
securities, cash or other assets, as the case may be) as to which the Rights are
exercised, at any time which is both after the Distribution Date and prior to
the time (the "Expiration Date") that is the earliest of (i) the Close of
Business on April 6, 2008 (the "Final Expiration Date"), (ii) the time at which
the Rights are redeemed as provided in Section 23 hereof (the "Redemption Date")
or (iii) the time at which such Rights are exchanged as provided in Section 24
hereof.

                  (b)      The Purchase Price shall be initially $35.00 for each
one one-thousandth of a share of Preferred Stock purchasable upon the exercise
of a Right. The Purchase Price and the number of one one-thousandths of a share
of Preferred Stock or other securities or property to be acquired upon exercise
of a Right shall be subject to adjustment from time to time as provided in
Sections 11 and 13 hereof and shall be payable in lawful money of the United
States of America in accordance with paragraph (c) of this Section 7.

                  (c)      Except as otherwise provided herein, upon receipt of
a Right Certificate representing exercisable Rights, with the form of election
to purchase duly executed, accompanied by payment of the aggregate Purchase
Price for the shares of Preferred Stock to be purchased and an amount equal to
any applicable transfer tax required to be paid by the holder of such Right
Certificate in accordance with Section 9 hereof, in cash or by certified check,
cashier's check or money order payable to the order of the Company, the Rights
Agent shall thereupon promptly (i) (A) requisition from any transfer agent of
the Preferred Stock certificates for the number of shares of


                                        8

<PAGE>   12



Preferred Stock to be purchased and the Company hereby irrevocably authorizes
its transfer agent to comply with all such requests, or (B) requisition from the
depositary agent depositary receipts representing interests in such number of
one one-thousandths of a share of Preferred Stock as are to be purchased (in
which case certificates for the 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 request, (ii)
when appropriate, requisition from the Company the amount of cash to be paid in
lieu of issuance of fractional shares in accordance with Section 14 hereof,
(iii) promptly 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
Right Certificate, registered in such name or names as may be designated by such
holder and (iv) when appropriate, after receipt, promptly deliver such cash to
or upon the order of the registered holder of such Right Certificate.

                  (d)      Except as otherwise provided herein, in case the
registered holder of any Right Certificate shall exercise less than all of the
Rights evidenced thereby, a new Right Certificate evidencing Rights equivalent
to the exercisable Rights remaining unexercised shall be issued by the Rights
Agent to the registered holder of such Right Certificate or to his duly
authorized assigns, subject to the provisions of Section 14 hereof.

                  (e)      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 of Rights upon the
occurrence of any purported transfer or exercise of Rights pursuant to Section 6
hereof or this Section 7 unless such registered holder shall have (i) completed
and signed the certificate contained in the form of assignment or form of
election to purchase set forth on the reverse side of the Rights Certificate
surrendered for such transfer or exercise and (ii) provided such additional
evidence of the identity of the Beneficial Owner (or former Beneficial Owner)
thereof as the Company shall reasonably request.

                  Section 8.    Cancellation and Destruction of Right 
Certificates.  All Right Certificates surrendered for the purpose of exercise, 
transfer, split up, combination or exchange shall, if surrendered to the Company
or to any of its agents, be delivered to the Rights Agent for cancellation or in
canceled form, or, if surrendered to the Rights Agent, shall be canceled by it,
and no Right 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 Right Certificate purchased or acquired by the
Company otherwise than upon the exercise thereof. The Rights Agent shall deliver
all canceled Right Certificates to the Company, or shall, at the written request
of the Company, destroy such canceled Right Certificates, and in such case shall
deliver a certificate of destruction thereof to the Company.

                  Section 9.    Availability of Shares of Preferred 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 or any shares of Preferred Stock held in its treasury, the
number of shares of Preferred Stock that will be sufficient to permit the
exercise in full of all outstanding Rights.


                                        9

<PAGE>   13



                  (b)      So long as the shares of Preferred Stock issuable
upon the exercise of Rights may be listed or admitted to trading on any national
securities exchange, or quoted on NASDAQ, 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 listed or admitted to trading on such exchange,
or quoted on NASDAQ, upon official notice of issuance upon such exercise.

                  (c)      From and after such time as the Rights become
exercisable, the Company shall use its best efforts, if then necessary to permit
the issuance of shares of Preferred Stock upon the exercise of Rights, to
register and qualify such shares of Preferred Stock under the Securities Act and
any applicable state securities or "Blue Sky" laws (to the extent exemptions
therefrom are not available), cause such registration statement and
qualifications to become effective as soon as possible after such filing and
keep such registration and qualifications effective until the earlier of the
date as of which the Rights are no longer exercisable for such securities and
the Expiration Date. The Company may temporarily suspend, for a period of time
not to exceed 90 days, the exercisability of the Rights in order to prepare and
file a registration statement under the Securities Act and permit it to become
effective. 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 qualification in such jurisdiction shall have been obtained and until
a registration statement under the Securities Act (if required) shall have been
declared effective.

                  (d)      The Company covenants and agrees that it will take
all such action as may be necessary to ensure that all shares of Preferred Stock
delivered upon exercise of Rights shall, at the time of delivery of the
certificates therefor (subject to payment of the Purchase Price), be duly and
validly authorized and issued and fully paid and nonassessable shares.

                  (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 which may be payable in respect of the issuance or delivery of the Right
Certificates or of any shares of Preferred Stock upon the exercise of Rights.
The Company shall not, however, be required to pay any transfer tax which may be
payable in respect of any transfer or delivery of Right Certificates to a Person
other than, or the issuance or delivery of certificates or depositary receipts
for the Preferred Stock in a name other than that of, the registered holder of
the Right Certificate evidencing Rights surrendered for exercise or to issue or
deliver any certificates or depositary receipts for Preferred Stock upon the
exercise of any Rights until any such tax shall have been paid (any such tax
being payable by that holder of such Right Certificate at the time of surrender)
or until it has been established to the Company's reasonable satisfaction that
no such tax is due.

                  Section 10.       Preferred Stock Record Date. Each Person in
whose name any certificate for Preferred Stock is issued upon the exercise of
Rights shall for all purposes be deemed to have become the holder of record of
the shares of Preferred Stock represented thereby on, and such certificate shall
be dated, the date upon which the Right Certificate evidencing such Rights was
duly surrendered and payment of the Purchase Price (and any applicable transfer
taxes) was made; provided, however, that if the date of such surrender and
payment is a date upon which the Preferred Stock transfer books of the Company
are closed, such Person shall be deemed to have become the


                                       10

<PAGE>   14



record holder of such shares on, and such certificate shall be dated, the next
succeeding Business Day on which the Preferred Stock transfer books of the
Company are open. Prior to the exercise of the Rights evidenced thereby, the
holder of a Right Certificate shall not be entitled to any rights of a holder of
Preferred Stock for which the Rights shall be exercisable, including, without
limitation, the right to vote or to receive dividends or other distributions,
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 and Number of Rights. The Purchase Price, the number of shares of
Preferred Stock or other securities or property purchasable upon exercise of
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 and pay 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 of Preferred Stock 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),
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 capital stock issuable on such date, shall be
proportionately adjusted so that the holder of any Right exercised after such
time shall be entitled to receive the aggregate number and kind of shares of
capital stock 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, the holder would have owned upon such exercise and been entitled to
receive by virtue of such dividend, subdivision, combination or
reclassification; provided, however, that in no event shall the consideration to
be paid upon the exercise of one Right be less than the aggregate par value of
the shares of capital stock of the Company issuable upon exercise of one Right.

                  (ii)     Subject to Section 24 of this Agreement, in the 
event any Person becomes an Acquiring Person (the first occurrence of such event
being referred to hereinafter as the "Flip-In Event"), then (A) the Purchase
Price shall be adjusted to be the Purchase Price in effect immediately prior to
the Flip-In Event multiplied by the number of one one-thousandths of a share of
Preferred Stock for which a Right was exercisable immediately prior to such
Flip-In Event, whether or not such Right was then exercisable, and (B) each
holder of a Right, except as otherwise provided in this Section 11(a)(ii) and
Section 11(a)(iii) hereof, shall thereafter have the right to receive, upon
exercise thereof at a price equal to the Purchase Price (as so adjusted), in
accordance with the terms of this Agreement and in lieu of shares of Preferred
Stock, such number of shares of Common Stock as shall equal the result obtained
by dividing the Purchase Price (as so adjusted) by 50% of the current per share
market price of the Common Stock (determined pursuant to Section 11(d) hereof)
on the date of such Flip-In Event; provided, however, that the Purchase Price
(as so adjusted) and the number of shares of Common Stock so receivable upon
exercise of a Right shall, following the Flip-In Event, be subject to further
adjustment as appropriate in accordance with Section 11(f) hereof.
Notwithstanding anything in this Agreement to the contrary, however, from and
after the Flip-In Event, any Rights that are beneficially owned by (x) any
Acquiring Person (or any Affiliate or Associate of any Acquiring Person), (y) a
transferee of any Acquiring Person (or any such Affiliate



                                       11

<PAGE>   15



or Associate) who becomes a transferee after the Flip-In Event or (z) a
transferee of any Acquiring Person (or any such Affiliate or Associate) who
became a transferee prior to or concurrently with the Flip-In Event pursuant to
either (i) a transfer from the Acquiring Person to holders of its equity
securities or to any Person with whom it has any continuing agreement,
arrangement or understanding regarding the transferred Rights or (ii) a transfer
which the Board of Directors has determined is part of a plan, arrangement or
understanding which has the purpose or effect of avoiding the provisions of this
paragraph, and subsequent transferees of such Persons, shall be void without any
further action and any holder of such Rights shall thereafter have no rights
whatsoever with respect to such Rights under any provision of this Agreement.
The Company shall use all reasonable efforts to ensure that the provisions of
this Section 11(a)(ii) are complied with, but shall have no liability to any
holder of Right 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. From and after the Flip-In Event, no Right
Certificate shall be issued pursuant to Section 3 or Section 6 hereof that
represents Rights that are or have become void pursuant to the provisions of
this paragraph, and any Right Certificate delivered to the Rights Agent that
represents Rights that are or have become void pursuant to the provisions of
this paragraph shall be canceled. From and after the occurrence of an event
specified in Section 13(a) hereof, any Rights that theretofore have not been
exercised pursuant to this Section 11(a)(ii) shall thereafter be exercisable
only in accordance with Section 13 and not pursuant to this Section 11(a)(ii).

                  (iii)    The Company may at its option substitute for a share
of Common Stock issuable upon the exercise of Rights in accordance with the
foregoing subparagraph (ii) a number of shares of Preferred Stock or fraction
thereof such that the current per share market price of one share of Preferred
Stock multiplied by such number or fraction is equal to the current per share
market price of one share of Common Stock. In the event that there shall not be
sufficient shares of Common Stock issued but not outstanding or authorized but
unissued to permit the exercise in full of the Rights in accordance with the
foregoing subparagraph (ii), the Board of Directors shall, to the extent
permitted by applicable law and any material agreements then in effect to which
the Company is a party, (A) determine the excess (such excess, the "Spread") of
(1) the value of the shares of Common Stock issuable upon the exercise of a
Right in accordance with the foregoing subparagraph (ii) (the "Current Value")
over (2) the Purchase Price (as adjusted in accordance with the foregoing
subparagraph (ii)), and (B) with respect to each Right (other than Rights which
have become void pursuant to the foregoing subparagraph (ii)), make adequate
provision to substitute for the shares of Common Stock issuable in accordance
with the foregoing subparagraph (ii) upon exercise of the Right and payment of
the Purchase Price (as adjusted in accordance therewith), (1) cash, (2) a
reduction in such Purchase Price, (3) shares of Preferred Stock or other equity
securities of the Company (including, without limitation, shares or fractions of
shares of preferred stock which, by virtue of having dividend, voting and
liquidation rights substantially comparable to those of the shares of Common
Stock, are deemed in good faith by the Board of Directors to have substantially
the same value as the shares of Common Stock (such shares of Preferred Stock and
shares or fractions of shares of preferred stock are hereinafter referred to as
"Common Stock Equivalents")), (4) debt securities of the Company, (5) other
assets, or (6) any combination of the foregoing, having a value which, when
added to the value of the shares of Common Stock issued upon exercise of such
Right, shall have an aggregate value equal to the Current Value (less the amount
of any reduction in such Purchase Price), where such aggregate value has been
determined by the Board of Directors upon the advice of a nationally recognized
investment banking firm selected in good faith by the



                                       12

<PAGE>   16



Board of Directors; provided, however, that if the Company shall not make
adequate provision to deliver value pursuant to clause (B) above within thirty
(30) days following the Flip-In Event (the "Section 11(a)(ii) Trigger Date"),
then the Company shall be obligated to deliver, to the extent permitted by
applicable law and any material agreements then in effect to which the Company
is a party, upon the surrender for exercise of a Right and without requiring
payment of such Purchase Price, shares of Common Stock (to the extent
available), and then, if necessary, such number or fractions of shares of
Preferred Stock (to the extent available) and then, if necessary, cash, which
shares and/or cash have an aggregate value equal to the Spread. If, upon the
occurrence of the Flip-In Event, the Board of Directors 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, then, if the
Board of Directors so elects, 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 stockholder
approval for the authorization of such additional shares (such thirty (30) day
period, as it may be extended, is herein called the "Substitution Period"). To
the extent that the Company determines that some action need be taken pursuant
to the second and/or third sentence of this Section 11(a)(iii), the Company (x)
shall provide, subject to Section 11(a)(ii) hereof and the last sentence of this
Section 11(a)(iii) 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 second 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 shares of
Common Stock shall be the current per share market price (as determined pursuant
to Section 11(d)(i)) on the Section 11(a)(ii) Trigger Date and the per share or
fractional value of any "Common Stock Equivalent" shall be deemed to equal the
current per share market price of the Common Stock. The Board of Directors of
the Company may, but shall not be required to, establish procedures to allocate
the right to receive shares of Common Stock upon the exercise of the Rights
among holders of Rights pursuant to this Section 11(a)(iii).

                  (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 (for a period expiring within 45 calendar days after such record
date) to subscribe for or purchase Preferred Stock (or shares having the same
rights, privileges and preferences as the Preferred Stock ("equivalent preferred
shares")) or securities convertible into Preferred Stock or equivalent preferred
shares at a price per share of Preferred Stock or equivalent preferred shares
(or having a conversion price per share, if a security convertible into shares
of Preferred Stock or equivalent preferred shares) less than the then current
per share market price of the Preferred Stock (determined pursuant to Section
11(d) hereof) 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 and equivalent preferred shares
outstanding on such record date plus the number of shares of Preferred Stock and
equivalent preferred shares which the aggregate offering price of the total
number of shares of Preferred Stock and/or equivalent preferred shares 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



                                       13

<PAGE>   17



the number of shares of Preferred Stock and equivalent preferred shares
outstanding on such record date plus the number of additional shares of
Preferred Stock and/or equivalent preferred shares to be offered for
subscription or purchase (or into which the convertible securities so to be
offered are initially convertible); provided, however, that in no event shall
the consideration to be paid upon the exercise of one Right be less than the
aggregate par value of the shares of capital stock of the Company issuable upon
exercise of one Right. In case such subscription price may be paid in a
consideration part or all of which shall be in a form other than cash, the value
of such consideration shall be as determined in good faith by the Board of
Directors of the Company, whose determination shall be described in a statement
filed with the Rights Agent. Shares of Preferred Stock and equivalent preferred
shares 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 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 the
making of a distribution to all holders of the Preferred Stock (including any
such distribution made in connection with a consolidation or merger in which the
Company is the continuing or surviving corporation) of evidences of indebtedness
or assets (other than a regular quarterly cash dividend or a dividend payable in
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
then current per share market price of the Preferred Stock (determined pursuant
to Section 11(d) hereof) on such record date, less the fair market value (as
determined in good faith by the Board of Directors of the Company whose
determination shall be described in a statement filed with the Rights Agent) of
the portion of the assets or evidences of indebtedness so to be distributed or
of such subscription rights or warrants applicable to one share of Preferred
Stock, and the denominator of which shall be such current per share market price
(determined pursuant to Section 11(d) hereof) of the Preferred Stock; provided,
however, that in no event shall the consideration to be paid upon the exercise
of one Right be less than the aggregate par value of the shares of capital stock
of the Company to be issued upon exercise of one Right. 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 again be adjusted to
be the Purchase Price which would then be in effect if such record date had not
been fixed.

                  (d)(i)   Except as otherwise provided herein, for the purpose
of any computation hereunder, the "current per share market price" of any
security (a "Security" for the purpose of this Section 11(d)(i)) on any date
shall be deemed to be the average of the daily closing prices per share of such
Security for the 30 consecutive Trading Days (as such term is hereinafter
defined) immediately prior to such date; provided, however, that in the event
that the current per share market price of the Security is determined during a
period following the announcement by the issuer of such Security of (A) a
dividend or distribution on such Security payable in shares of such Security or
securities convertible into such shares, or (B) any subdivision, combination or
reclassification of such Security, and prior to the expiration of 30 Trading
Days after the ex-dividend date for such dividend or distribution, or the record
date for such subdivision, combination or reclassification, then, and in each
such case, the current per share market price shall be appropriately adjusted to



                                       14

<PAGE>   18



reflect the current market price per share equivalent of such Security. 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 by the principal
consolidated transaction reporting system with respect to securities listed or
admitted to trading on the New York Stock Exchange or, if the Security is not
listed or admitted to trading on the New York Stock Exchange, as reported in the
principal consolidated transaction reporting system with respect to securities
listed on the principal national securities exchange on which the Security is
listed or admitted to trading or, if the Security is 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 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 Security is 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 Security selected by the Board of Directors of the
Company. The term "Trading Day" shall mean a day on which the principal national
securities exchange on which the Security is listed or admitted to trading is
open for the transaction of business or, if the Security is not listed or
admitted to trading on any national securities exchange, a Business Day.

                  (ii)     For the purpose of any computation hereunder, if the
Preferred Stock is publicly traded, the "current per share market price" of the
Preferred Stock shall be determined in accordance with the method set forth in
Section 11(d)(i). If the Preferred Stock is not publicly traded but the Common
Stock is publicly traded, the "current per share market price" of the Preferred
Stock shall be conclusively deemed to be the current per share market price of
the Common Stock as determined pursuant to Section 11(d)(i) multiplied by the
then applicable Adjustment Number (as defined in and determined in accordance
with the Certificate of Designation for the Preferred Stock). If neither the
Common Stock nor the Preferred Stock is publicly traded, "current per share
market price" shall mean the fair value per share as determined in good faith by
the Board of Directors of the Company, whose determination shall be described in
a statement filed with the Rights Agent.

                  (e)      No adjustment in the Purchase Price shall be required
unless such adjustment would require an increase or decrease of at least 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 one
hundred-thousandth of a share of Preferred Stock or one-hundredth of a share of
Common Stock or other share or 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 requires such adjustment or (ii) the Expiration Date.

                  (f)      If as a result of an adjustment made pursuant to 
Section 11(a) hereof, the holder of any Right thereafter exercised shall become
entitled to receive any shares of capital stock of the Company other than the
Preferred Stock, thereafter the Purchase Price and the number of such other
shares so receivable upon exercise of a Right 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), 11(b), 11(c), 11(e), 11(h), 11(i) and 11(m) hereof, as applicable, 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 shares.



                                       15

<PAGE>   19




                  (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 11(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 one
hundred-thousandth of a share of Preferred Stock) obtained by (i) multiplying
(x) the number of one one-thousandths of a share purchasable upon the exercise
of a Right immediately prior to such 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 pursuant to Sections 11(b) or 11(c) hereof to
adjust the number of Rights, in substitution for 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 such adjustment of 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-hundredth) 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. Such record date may be the date on which the Purchase
Price is adjusted or any day thereafter, but, if the Right Certificates have
been issued, shall be at least 10 days later than the date of the public
announcement. If Right Certificates have been issued, upon each adjustment of
the number of Rights pursuant to this Section 11(i), the Company may, as
promptly as practicable, cause to be distributed to holders of record of Right
Certificates on such record date Right 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 the Company, shall cause to
be distributed to such holders of record in substitution and replacement for the
Right Certificates held by such holders prior to the date of adjustment, and
upon surrender thereof, if required by the Company, new Right Certificates
evidencing all the Rights to which such holders shall be entitled after such
adjustment. Right Certificates so to be distributed shall be issued, executed
and countersigned in the manner provided for herein and shall be registered in
the names of the holders of record of Right 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 a Right, the Right Certificates theretofore
and thereafter issued may continue to express the Purchase Price and the number
of one one-thousandths of a share of Preferred Stock which were expressed in the
initial Right Certificates issued hereunder.




                                       16

<PAGE>   20




                  (k)      Before taking any action that would cause an
adjustment reducing the Purchase Price below the then par value, if any, of the
fraction of Preferred Stock or other shares of capital stock issuable upon
exercise of a Right, 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 fully paid and nonassessable shares of Preferred Stock or
other such shares 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 issuing to the holder of any Right exercised after such record date
the Preferred Stock and other capital stock or securities of the Company, if
any, issuable upon such exercise over and above the 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 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 adjustments in the
Purchase Price, in addition to those adjustments expressly required by this
Section 11, as and to the extent that it in its sole discretion shall determine
to be advisable in order that any consolidation or subdivision of the Preferred
Stock, issuance wholly for cash of any shares of Preferred Stock at less than
the current market price, issuance wholly for cash of Preferred Stock or
securities which by their terms are convertible into or exchangeable for
Preferred Stock, dividends on Preferred Stock payable in shares of Preferred
Stock or issuance of rights, options or warrants referred to hereinabove in
Section 11(b), hereafter made by the Company to holders of its Preferred Stock
shall not be taxable to such stockholders.

                  (n)      Anything in this Agreement to the contrary
notwithstanding, in the event that at any time after the date of this Rights
Agreement and prior to the Distribution Date, the Company shall (i) declare and
pay any dividend on the Common Stock payable in Common Stock or (ii) effect a
subdivision, combination or consolidation of the Common Stock (by
reclassification or otherwise than by payment of a dividend payable in Common
Stock) into a greater or lesser number of shares of Common Stock, then, in each
such case, the number of Rights associated with each share of Common Stock then
outstanding, or issued or delivered thereafter, 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 total number of shares of Common Stock outstanding immediately prior to the
occurrence of the event and the denominator of which shall be the total number
of shares of Common Stock outstanding immediately following the occurrence of
such event.

                  (o)      The Company agrees that, after the earlier of the
Distribution Date or the Stock Acquisition Date, it will not, except as
permitted by Sections 23, 24 or 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 eliminate the
benefits intended to be afforded by the Rights.

                           

                                       17

<PAGE>   21




                  Section 12.   Certificate of Adjusted Purchase Price or Number
of Shares. Whenever an adjustment is made as provided in Section 11 or 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 Common Stock
and the Preferred Stock a copy of such certificate and (c) mail a brief summary
thereof to each holder of a Right Certificate in accordance with Section 25
hereof (if so required under Section 25 hereof). The Rights Agent shall be fully
protected in relying on any such certificate and on any adjustment therein
contained and shall not be deemed to have knowledge of any such 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, directly or indirectly, at any time
after the Flip-In Event (i) the Company shall consolidate with or shall merge
into any other Person, (ii) any Person shall merge with and into the Company and
the Company shall be the continuing or surviving corporation of such merger and,
in connection with such merger, all or part of the Common Stock shall be changed
into or exchanged for stock or other securities of any other Person (or of the
Company) or cash or any other property, or (iii) the Company shall sell or
otherwise transfer (or one or more of its Subsidiaries shall sell or otherwise
transfer), in one or more transactions, assets or earning power aggregating 50%
or more of the assets or earning power of the Company and its Subsidiaries
(taken as a whole) to any other Person (other than the Company or one or more
wholly-owned Subsidiaries of the Company), then upon the first occurrence of
such event, proper provision shall be made so that: (A) each holder of a Right
(other than Rights which have become void pursuant to Section 11(a)(ii) hereof)
shall thereafter have the right to receive, upon the exercise thereof at the
Purchase Price (as theretofore adjusted in accordance with Section 11(a)(ii)
hereof), in accordance with the terms of this Agreement and in lieu of shares of
Preferred Stock or Common Stock of the Company, 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), not
subject to any liens, encumbrances, rights of first refusal or other adverse
claims, as shall equal the result obtained by dividing the Purchase Price (as
theretofore adjusted in accordance with Section 11(a)(ii) hereof) by 50% of the
current per share market price of the Common Stock of such Principal Party
(determined pursuant to Section 11(d) hereof) on the date of consummation of
such consolidation, merger, sale or transfer; provided, however, that the
Purchase Price (as theretofore adjusted in accordance with Section 11(a)(ii)
hereof) and the number of shares of Common Stock of such Principal Party so
receivable upon exercise of a Right shall be subject to further adjustment as
appropriate in accordance with Section 11(f) hereof to reflect any events
occurring in respect of the Common Stock of such Principal Party after the
occurrence of such consolidation, merger, sale or transfer; (B) such Principal
Party shall thereafter be liable for, and shall assume, by virtue of such
consolidation, merger, sale or transfer, all the obligations and duties of the
Company pursuant to this Rights Agreement; (C) the term "Company" shall
thereafter be deemed to refer to such Principal Party; and (D) such Principal
Party shall take such steps (including, but not limited to, the reservation of a
sufficient number of its shares of Common Stock in accordance with Section 9
hereof) in connection with such 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 the shares of its Common Stock
thereafter deliverable upon the exercise of the Rights; provided that, upon the
subsequent occurrence of any consolidation, merger, sale or transfer of assets
or other


                                       18

<PAGE>   22



extraordinary transaction in respect of such Principal Party, each holder of a
Right shall thereupon be entitled to receive, upon exercise of a Right and
payment of the Purchase Price as provided in this Section 13(a), such cash,
shares, rights, warrants and other property which such holder would have been
entitled to receive had such holder, at the time of such transaction, owned the
Common Stock of the Principal Party receivable upon the exercise of a Right
pursuant to this Section 13(a), and such Principal Party shall take such steps
(including, but not limited to, reservation of shares of stock) as may be
necessary to permit the subsequent exercise of the Rights in accordance with the
terms hereof for such cash, shares, rights, warrants and other property.

                  (b)      "Principal Party" shall mean:

                           (i)      in the case of any transaction described in
(i) or (ii) of the first sentence of Section 13(a) hereof: (A) the Person that
is the issuer of the securities into which the shares of Common Stock are
converted in such merger or consolidation, or, if there is more than one such
issuer, the issuer the shares of Common Stock of which have the greatest
aggregate market value of shares outstanding, or (B) if no securities are so
issued, (x) the Person that is the other party to the merger, if such Person
survives said merger, or, if there is more than one such Person, the Person the
shares of Common Stock of which have the greatest aggregate market value of
shares outstanding or (y) if the Person that is the other party to the merger
does not survive the merger, the Person that does survive the merger (including
the Company if it survives) or (z) the Person resulting from the consolidation;
and

                           (ii)     in the case of any transaction described in
(iii) of the first sentence in Section 13(a) hereof, the Person that is the
party receiving the greatest portion of the assets or earning power transferred
pursuant to such transaction or transactions, or, if each Person that is a party
to such transaction or transactions receives the same portion of the assets or
earning power so transferred or if the Person receiving the greatest portion of
the assets or earning power cannot be determined, whichever of such Persons is
the issuer of Common Stock having the greatest aggregate market value of shares
outstanding; provided, however, that in any such case described in the foregoing
clause (b)(i) or (b)(ii), if the Common Stock of such Person is not at such time
or has not been continuously over the preceding 12-month period registered under
Section 12 of the Exchange Act, then (1) if such Person is a direct or indirect
Subsidiary of another Person the Common Stock of which is and has been so
registered, the term "Principal Party" shall refer to such other Person, or (2)
if such Person is a Subsidiary, directly or indirectly, of more than one Person,
the Common Stock of all of which is and has been so registered, the term
"Principal Party" shall refer to whichever of such Persons is the issuer of
Common Stock having the greatest aggregate market value of shares outstanding,
or (3) if 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 clauses (1) and (2) above shall apply to
each of the owners having an interest in the venture as if the Person owned by
the joint venture was a Subsidiary of both or all of such joint venturers, and
the Principal Party in each such case shall bear the obligations set forth in
this Section 13 in the same ratio as its interest in such Person bears to the
total of such interests.

                  (c)      The Company shall not consummate any consolidation,
merger, sale or transfer referred to in Section 13(a) hereof unless prior
thereto the Company and the Principal Party involved therein shall have executed
and delivered to the Rights Agent an agreement confirming that



                                       19

<PAGE>   23



the requirements of Sections 13(a) and (b) hereof shall promptly be performed in
accordance with their terms and that such consolidation, merger, sale or
transfer of assets shall not result in a default by the Principal Party under
this Agreement as the same shall have been assumed by the Principal Party
pursuant to Sections 13(a) and (b) hereof and providing that, as soon as
practicable after executing such agreement pursuant to this Section 13, the
Principal Party will:

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

                           (ii)     use its best efforts, if the Common Stock of
the Principal Party shall be listed or admitted to trading on the New York Stock
Exchange or on another national securities exchange, to list or admit to trading
(or continue the listing of) the Rights and the securities purchasable upon
exercise of the Rights on the New York Stock Exchange or such securities
exchange, or, if the Common Stock of the Principal Party shall not be listed or
admitted to trading on the New York Stock Exchange or a national securities
exchange, to cause the Rights and the securities receivable upon exercise of the
Rights to be authorized for quotation on NASDAQ or on such other system then in
use;

                           (iii)            deliver to holders of the Rights 
historical financial statements for the Principal Party which comply in all
respects with the requirements for registration on Form 10 (or any successor
form) under the Exchange Act; and

                           (iv)     obtain waivers of any rights of first
refusal or preemptive rights in respect of the Common Stock of the Principal
Party subject to purchase upon exercise of outstanding Rights.

                  (d)      In case the Principal Party has provision in any of
its authorized securities or in its certificate of incorporation or by-laws or
other instrument governing its corporate affairs, which provision would have the
effect of (i) causing such Principal Party to issue (other than to holders of
Rights pursuant to this Section 13), in connection with, or as a consequence of,
the consummation of a transaction referred to in this Section 13, shares of
Common Stock or Common Stock Equivalents of such Principal Party at less than
the then current market price per share thereof (determined pursuant to Section
11(d) hereof) or securities exercisable for, or convertible into, Common Stock
or Common Stock Equivalents of such Principal Party at less than such then
current market price, or (ii) providing for any special payment, tax or similar
provision in connection with the issuance of the Common Stock of such Principal
Party pursuant to the provisions of Section 13, then, in such event, the Company
hereby agrees with each holder of Rights that it shall not consummate any such
transaction unless prior thereto the Company and such Principal Party shall have
executed and delivered to the Rights Agent a supplemental agreement providing
that the provision in question of such Principal Party shall have been canceled,
waived or amended, or that the authorized securities shall be redeemed, so that
the applicable provision will have no effect in connection with, or as a
consequence of, the consummation of the proposed transaction.



                                       20

<PAGE>   24




                  (e)      The Company covenants and agrees that it shall not,
at any time after the Flip-In Event, enter into any transaction of the type
described in clauses (i) through (iii) of Section 13(a) hereof if (i) at the
time of or immediately after such consolidation, merger, sale, transfer or other
transaction there are any rights, warrants or other instruments or securities
outstanding or agreements in effect which would substantially diminish or
otherwise eliminate the benefits intended to be afforded by the Rights, (ii)
prior to, simultaneously with or immediately after such consolidation, merger,
sale, transfer or other transaction, the stockholders of the Person who
constitutes, or would constitute, the Principal Party for purposes of Section
13(b) hereof shall have received a distribution of Rights previously owned by
such Person or any of its Affiliates or Associates or (iii) the form or nature
of organization of the Principal Party would preclude or limit the
exercisability of the Rights.

                  Section 14.   Fractional Rights and Fractional Shares.

                  (a)      The Company shall not be required to issue fractions
of Rights or to distribute Right Certificates which evidence fractional Rights
(except prior to the Distribution Date in accordance with Section 11(n) hereof).
In lieu of such fractional Rights, there shall be paid to the registered holders
of the Right 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 the 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 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 New York
Stock Exchange or, if the Rights are not listed or admitted to trading on the
New York Stock Exchange, as reported in the principal consolidated transaction
reporting system with respect to securities listed 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 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 of Directors of the Company. If on any such date no such
market maker is making a market in the Rights, the fair value of the Rights on
such date as determined in good faith by the Board of Directors of the Company
shall be used.

                  (b)      The Company shall not be required to issue fractions
of Preferred Stock (other than fractions which are integral multiples of one
one-thousandth of a share of Preferred Stock) or to distribute certificates
which evidence fractional shares of Preferred Stock (other than fractions which
are integral multiples of one one-thousandth of a share of Preferred Stock) upon
the exercise or exchange of Rights. Interests in fractions 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, pursuant to an
appropriate agreement between the Company and a depositary selected by it;
provided, that such agreement shall provide that the holders of such depositary
receipts shall have all the rights, privileges and preferences to which they are
entitled as beneficial owners of the Preferred Stock represented by such
depositary receipts. In lieu of fractional shares



                                       21

<PAGE>   25



of Preferred Stock that are not integral multiples of one one-thousandth of a
share of Preferred Stock, the Company shall pay to the registered holders of
Right Certificates at the time such Rights are exercised or exchanged as herein
provided an amount in cash equal to the same fraction of the current market
value of a whole share of Preferred Stock (as determined in accordance with
Section 14(a) hereof) for the Trading Day immediately prior to the date of such
exercise or exchange.

                  (c)      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 upon the exercise or exchange of Rights. In
lieu of such fractional shares of Common Stock, the Company shall pay 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 (as determined in accordance with Section 14(a) hereof) for the
Trading Day immediately prior to the date of such exercise or exchange.

                  (d)      The holder of a Right by the acceptance of the Right
expressly waives his right to receive any fractional Rights or any fractional
shares upon exercise or exchange of a Right (except as provided above).

                  Section 15.   Rights of Action. All rights of action in 
respect of this Agreement, excepting the rights of action given to the Rights
Agent under Section 18 hereof, are vested in the respective registered holders
of the Right Certificates (and, prior to the Distribution Date, the registered
holders of the Common Stock); and any registered holder of any Right 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 Right Certificate (or, prior
to the Distribution Date, of the Common Stock), on his own behalf and for his
own benefit, may 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 Right Certificate (or, prior to
the Distribution Date, such Common Stock) in the manner provided therein 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
will be entitled to specific performance of the obligations under, and
injunctive relief against actual or threatened violations of, the obligations of
any Person subject to this Agreement.

                  Section 16.   Agreement of Right 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 the Common Stock;

                  (b)      after the Distribution Date, the Right Certificates 
are transferable only on the registry books of the Rights Agent if surrendered
at the office or agency of the Rights Agent designated for such purpose, duly
endorsed or accompanied by a proper instrument of transfer; and

                  (c)      the Company and the Rights Agent may deem and treat 
the Person in whose name the Right Certificate (or, prior to the Distribution
Date, the Common Stock certificate) is



                                       22

<PAGE>   26



registered as the absolute owner thereof and of the Rights evidenced thereby
(notwithstanding any notations of ownership or writing on the Right Certificates
or the 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 shall be affected by any notice to the contrary.

                  Section 17.   Right Certificate Holder Not Deemed a

Stockholder.  No holder, as such, of any Right Certificate shall be entitled to
vote, receive dividends or be deemed for any purpose the holder of the Preferred
Stock or any other securities of the Company which may at any time be issuable
on the exercise or exchange of the Rights represented thereby, nor shall
anything contained herein or in any Right Certificate be construed to confer
upon the holder of any Right 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 this Agreement), or
to receive dividends or subscription rights, or otherwise, until the Rights
evidenced by such Right Certificate shall have been exercised or exchanged 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 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 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 arising therefrom, directly or indirectly.

                  (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
Right Certificate or certificate for the Preferred Stock or 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 stock transfer or corporate trust powers 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,

                           

                                       23

<PAGE>   27



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 Right Certificates shall have been countersigned but not delivered,
any such successor Rights Agent may adopt the countersignature of the
predecessor Rights Agent and deliver such Right Certificates so countersigned;
and in case at that time any of the Right Certificates shall not have been
countersigned, any successor Rights Agent may countersign such Right
Certificates either in the name of the predecessor Rights Agent or in the name
of the successor Rights Agent; and in all such cases such Right Certificates
shall have the full force provided in the Right 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 Right Certificates shall have been
countersigned but not delivered, the Rights Agent may adopt the countersignature
under its prior name and deliver Right Certificates so countersigned; and in
case at that time any of the Right Certificates shall not have been
countersigned, the Rights Agent may countersign such Right Certificates either
in its prior name or in its changed name and in all such cases such Right
Certificates shall have the full force provided in the Right 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
Right 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 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 President and the 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 to the 
Company and any other Person only for its own negligence, bad faith or willful
misconduct. Anything to the contrary notwithstanding, in no event shall the
Rights Agent be liable for special, indirect, consequential or incidental loss
or damage of any kind whatsoever (including but not limited to lost profits),
even if the Rights Agent has been advised of the likelihood of such loss or
damage.

                  (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 Right Certificates (except its countersignature thereof) or be required to
verify the same, but all such statements and recitals are and shall be deemed to
have been made by the Company only.



                                       24

<PAGE>   28




                  (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 Right 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 Right
Certificate; nor shall it be responsible for any change in the exercisability of
the Rights (including the Rights becoming void pursuant to Section 11(a)(ii)
hereof) or any adjustment in the terms of the Rights provided for in Sections 3,
11, 13, 23 and 24, or the ascertaining of the existence of facts that would
require any such change or adjustment (except with respect to the exercise of
Rights evidenced by Right Certificates after receipt of a certificate furnished
pursuant to Section 12, describing such change or adjustment); 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 Preferred Stock or other
securities to be issued pursuant to this Agreement or any Right Certificate or
as to whether any shares of Preferred Stock or other securities will, when
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
any person reasonably believed by the Rights Agent to be one of the President or
the Secretary 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 by it in good faith in accordance with instructions of
any such officer or for any delay in acting while waiting for those
instructions. 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 under this Agreement
and the date on and/or after which such action shall be taken or such omission
shall be effective. The Rights Agent shall not be liable for any action taken
by, or omission of, the Rights Agent in accordance with a proposal included in
any such application on or after the date specified in such application (which
date shall not be less than five Business Days after the date any officer of the
Company actually receives such application unless any such officer shall have
consented in writing to an earlier date) unless, prior to taking any such action
(or the effective date in the case of an omission), the Rights Agent shall have
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



                                       25

<PAGE>   29



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
reasonable care was exercised in the selection and continued employment thereof.

                  (j)      If, with respect to any Rights Certificate
surrendered to the Rights Agent for exercise or transfer, the certificate
contained in the form of assignment or the form of election to purchase set
forth on the reverse thereof, as the case may be, has not been completed to
certify the holder is not an Acquiring Person (or an Affiliate or Associate
thereof), the Rights Agent shall not take any further action with respect to
such requested exercise or transfer without first consulting with the Company.

                  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 30 days' notice in writing mailed to the Company and to each
transfer agent of the Common Stock or Preferred Stock by registered or certified
mail, and, following the Distribution Date, to the holders of the Right
Certificates by first-class mail. The Company may remove the Rights Agent or any
successor Rights Agent upon 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 or Preferred Stock by registered or certified mail, and,
following the Distribution Date, to the holders of the Right Certificates by
first-class mail. 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 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 Right Certificate (who shall,
with such notice, submit his Right Certificate for inspection by the Company),
then the registered holder of any Right 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
either (a) a corporation organized and doing business under the laws of the
United States or the laws of any state of the United States or the District of
Columbia, in good standing, having an office in the State of Texas or the State
of New York, 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 million or (b) an affiliate of such
a corporation. 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 or Preferred Stock, and, following the Distribution Date, mail
a notice thereof in writing to the registered holders of the Right 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.




                                       26

<PAGE>   30



                  Section 22.   Issuance of New Right Certificates.
Notwithstanding any of the provisions of this Agreement or of the Rights to the
contrary, the Company may, at its option, issue new Right Certificates
evidencing Rights in such forms as may be approved by its Board of Directors to
reflect any adjustment or change in the Purchase Price and the number or kind or
class of shares or other securities or property purchasable under the Right
Certificates made in accordance with the provisions of this Agreement. In
addition, in connection with the issuance or sale of Common Stock following the
Distribution Date and prior to the Expiration Date, the Company may with respect
to shares of Common Stock so issued or sold pursuant to (i) the exercise of
stock options, (ii) under any employee plan or arrangement, (iii) upon the
exercise, conversion or exchange of securities, notes or debentures issued by
the Company or (iv) a contractual obligation of the Company, in each case
existing prior to the Distribution Date, issue Rights Certificates representing
the appropriate number of Rights in connection with such issuance or sale.

                  Section 23.   Redemption.

                  (a)      The Board of Directors of the Company may, at any 
time prior to the Flip-In Event, redeem all but not less than all the then
outstanding Rights at a redemption price of $.01 per Right, appropriately
adjusted to reflect any stock split, stock dividend or similar transaction
occurring after the date hereof (the redemption price being hereinafter referred
to as the "Redemption Price"). The redemption of the Rights may be made
effective at such time, on such basis and with such conditions as the Board of
Directors in its sole discretion may establish. The Redemption Price shall be
payable, at the option of the Company, in cash, shares of Common Stock, or such
other form of consideration as the Board of Directors shall determine.

                  (b)      Immediately upon the action of the Board of Directors
ordering the redemption of the Rights pursuant to paragraph (a) of this Section
23 (or at such later time as the Board of Directors may establish for the
effectiveness of such redemption), and without any further action and without
any notice, the right to exercise the Rights will terminate and the only right
thereafter of the holders of Rights shall be to receive the Redemption Price.
The Company shall promptly give public notice of any such redemption; provided,
however, that the failure to give, or any defect in, any such notice shall not
affect the validity of such redemption. Within 10 days after such action of the
Board of Directors ordering the redemption of the Rights (or such later time as
the Board of Directors may establish for the effectiveness of such redemption),
the Company shall mail a notice of redemption to all the holders of the then
outstanding Rights at their last addresses as they appear 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 shall state the method by
which the payment of the Redemption Price will be made.

                  Section 24.   Exchange.

                  (a)      The Board of Directors of the Company may, at its
option, at any time after the Flip-In Event, exchange all or part of the then
outstanding and exercisable Rights (which shall not include Rights that have
become void pursuant to the provisions of Section 11(a)(ii) hereof) for 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



                                       27

<PAGE>   31



hereof (such amount per Right being hereinafter referred to as the "Exchange
Ratio"). Notwithstanding the foregoing, the Board of Directors shall not be
empowered to effect such exchange at any time after an Acquiring Person shall
have become the Beneficial Owner of shares of Common Stock aggregating 50% or
more of the shares of Common Stock then outstanding. From and after the
occurrence of an event specified in Section 13(a) hereof, any Rights that
theretofore have not been exchanged pursuant to this Section 24(a) shall
thereafter be exercisable only in accordance with Section 13 and may not be
exchanged pursuant to this Section 24(a). The exchange of the Rights by the
Board of Directors may be made effective at such time, on such basis and with
such conditions as the Board of Directors in its sole discretion may establish.

                  (b)      Immediately upon the effectiveness of the action of
the Board of Directors of the Company ordering the exchange of any Rights
pursuant to paragraph (a) of this Section 24 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
shall promptly mail a notice of any such exchange to all of the holders of the
Rights so exchanged 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 will state the method by which the exchange of the
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 11(a)(ii)
hereof) held by each holder of Rights.

                  (c)      The Company may at its option substitute, and, in the
event that there shall not be sufficient shares of Common Stock issued but not
outstanding or authorized but unissued to permit an exchange of Rights for
Common Stock as contemplated in accordance with this Section 24, the Company
shall substitute to the extent of such insufficiency, for each share of Common
Stock that would otherwise be issuable upon exchange of a Right, a number of
shares of Preferred Stock or fraction thereof (or equivalent preferred shares,
as such term is defined in Section 11(b)) such that the current per share market
price (determined pursuant to Section 11(d) hereof) of one share of Preferred
Stock (or equivalent preferred share) multiplied by such number or fraction is
equal to the current per share market price of one share of Common Stock
(determined pursuant to Section 11(d) hereof) as of the date of such exchange.

                  Section 25.   Notice of Certain Events.

                  (a)      In case the Company shall at any time after the
earlier of the Distribution Date or the Stock Acquisition Date propose (i) to
pay any dividend payable in stock of any class to the holders of its Preferred
Stock or to make any other distribution to the holders of its Preferred Stock
(other than a regular quarterly cash dividend), (ii) to offer to the holders of
its 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, (iii) to effect any reclassification of its
Preferred Stock (other than a reclassification involving only the subdivision or
combination of outstanding



                                       28

<PAGE>   32



Preferred Stock), (iv) to effect the liquidation, dissolution or winding up of
the Company, or (v) to pay any dividend on the Common Stock payable in Common
Stock or to effect a subdivision, combination or consolidation of the Common
Stock (by reclassification or otherwise than by payment of dividends in Common
Stock), then, in each such case, the Company shall give to each holder of a
Right Certificate, 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, or distribution of rights or warrants, or the date on which such
liquidation, dissolution or winding up is to take place and the date of
participation therein by the holders of the Common Stock and/or 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 10 days prior to the
record date for determining holders of the Preferred Stock for purposes of such
action, and in the case of any such other action, at least 10 days prior to the
date of the taking of such proposed action or the date of participation therein
by the holders of the Common Stock and/or Preferred Stock, whichever shall be
the earlier.

                  (b)      In case any event described in Section 11(a)(ii) or
Section 13 shall occur then the Company shall as soon as practicable thereafter
give to each holder of a Right Certificate (or if occurring prior to the
Distribution Date, the holders of the Common Stock) in accordance with Section
26 hereof, a notice of the occurrence of such event, which notice shall describe
such event and the consequences of such event to holders of Rights under Section
11(a)(ii) and Section 13 hereof.

                  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 Right
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:

                                Harken Energy Corporation
                                5605 N. MacArthur Boulevard, Suite 400
                                Irving, TX  75038
                                Attention: President

Subject to the provisions of Section 21 hereof, any notice or demand authorized
by this Agreement to be given or made by the Company or by the holder of any
Right 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:

                                ChaseMellon Shareholder Services L.L.C.
                                2323 Bryan Street, Suite 2300
                                Dallas, Texas 75201
                                Attention: Barbara J. Robbins

Notices or demands authorized by this Agreement to be given or made by the
Company or the Rights Agent to the holder of any Right Certificate 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.


                                      29
                                      
<PAGE>   33



                  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, 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 to (i) cure any
ambiguity, (ii) correct or supplement any provision contained herein which may
be defective or inconsistent with any other provision herein, (iii) shorten or
lengthen any time period hereunder, or (iv) change or supplement the provisions
hereunder in any manner which the Company may deem necessary or desirable;
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), and no such amendment may cause
the Rights again to become redeemable or cause the Agreement again to become
amendable other than in accordance with this sentence. Notwithstanding anything
contained in this Agreement to the contrary, no supplement or amendment shall be
made which changes the Redemption Price. 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.

                  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.   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 Right Certificates (and, prior to
the Distribution Date, 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 Right Certificates (and, prior to the Distribution Date, the Common Stock).

                  Section 30.   Determinations and Actions by the Board of
Directors. The Board of Directors of the Company shall have the exclusive power
and authority to administer this Agreement and to exercise the rights and powers
specifically granted to the Board of Directors of the Company 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, without
limitation, 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) that are done or made by the Board of Directors of the Company in
good faith, shall (x) be final, conclusive and binding on the Company, the
Rights Agent, the holders of the Rights, as such, and all other parties, and (y)
not subject the Board of Directors to any liability to the holders of the
Rights.

                  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



                                       30

<PAGE>   34



unenforceable, the remainder of the terms, provisions, covenants and
restrictions of this Agreement shall remain in full force and effect and shall
in no way be affected, impaired or invalidated.

                  Section 32.   Governing Law. This Agreement and each Right
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 such State applicable to contracts to
be made and performed entirely within such State.

                  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.



                                       31

<PAGE>   35




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

                                       HARKEN ENERGY CORPORATION


                                       By:  /s/ Bruce N. Huff
                                          -------------------------------------
                                                Bruce N. Huff,
                                                President and Chief Operating 
                                                Officer

                                       CHASEMELLON SHAREHOLDER SERVICES L.L.C.
                                       as Rights Agent


                                       By:  /s/ Margaret W. Grubb
                                          -------------------------------------
                                                Margaret W. Grubb,             
                                                Assistant Vice President



                                            


                                       32

<PAGE>   36


                                                                       Exhibit A


                                     FORM OF
                           CERTIFICATE OF DESIGNATION

                                       of

                  SERIES E JUNIOR PARTICIPATING PREFERRED STOCK

                                       of

                            HARKEN ENERGY CORPORATION

             Pursuant to Section 151 of the General Corporation Law
                            of the State of Delaware

                  Harken Energy Corporation, a corporation organized and
existing under the General Corporation Law of the State of Delaware, in
accordance with the provisions of Section 103 thereof, DOES HEREBY CERTIFY:

                  That pursuant to the authority vested in the Board of
Directors in accordance with the provisions of the Certificate of Incorporation
of the said Corporation, the said Board of Directors on April 6, 1998 adopted
the following resolution creating a series of 175,000 shares of Preferred Stock
designated as "Series E Junior Participating Preferred Stock":

                           RESOLVED, that pursuant to the authority
                  vested in the Board of Directors of this Corporation in
                  accordance with the provisions of the Certificate of
                  Incorporation, a series of Preferred Stock, par value $1.00
                  per share, of the Corporation be and hereby is created, and
                  that the designation and number of shares thereof and the
                  voting and other powers, preferences and relative,
                  participating, optional or other rights of the shares of such
                  series and the qualifications, limitations and restrictions
                  thereof are as follows:

                      Series E Junior Participating Preferred Stock

                  1.       Designation and Amount. There shall be a series of
Preferred Stock that shall be designated as "Series E Junior Participating
Preferred Stock," and the number of shares constituting such series shall be
175,000. Such number of shares may be increased or decreased by resolution of
the Board of Directors; provided, however, that no decrease shall reduce the
number of shares of Series E Junior Participating Preferred Stock to less than
the number of shares then issued and outstanding plus the number of shares
issuable upon exercise of outstanding rights, options or warrants or upon
conversion of outstanding securities issued by the Corporation.


                                  A-1

<PAGE>   37



                  2.       Dividends and Distribution.

                           (A)      Subject to the prior and superior rights of
the holders of any shares of any class or series of stock of the Corporation
ranking prior and superior to the shares of Series E Junior Participating
Preferred Stock with respect to dividends, the holders of shares of Series E
Junior Participating Preferred Stock, in preference to the holders of shares of
any class or series of stock of the Corporation ranking junior to the Series E
Junior Participating Preferred Stock in respect thereof, shall be entitled to
receive, when, as and if declared by the Board of Directors out of funds legally
available for the purpose, quarterly dividends payable in cash on the last day
of March, June, September and December, 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 E Junior Participating Preferred Stock, in an
amount per share (rounded to the nearest cent) equal to the greater of (a)
$10.00 or (b) the Adjustment Number (as defined below) times the aggregate per
share amount of all cash dividends, and the Adjustment Number 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, par value $.01 per share, of the
Corporation (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 E
Junior Participating Preferred Stock. The "Adjustment Number" shall initially be
1000. In the event the Corporation shall at any time after April 6, 1998 (the
"Rights Declaration Date") (i) declare and pay any dividend on Common Stock
payable in shares of Common Stock, (ii) subdivide the outstanding Common Stock
or (iii) combine the outstanding Common Stock into a smaller number of shares,
then in each such case the Adjustment Number in effect immediately prior to such
event shall be adjusted by multiplying such Adjustment 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.

                           (B)      The Corporation shall declare a dividend or
distribution on the Series E Junior Participating Preferred Stock as provided in
paragraph (A) above immediately after it declares a dividend or distribution on
the Common Stock (other than a dividend payable in shares of Common Stock).

                           (C)      Dividends shall begin to accrue and be 

cumulative on outstanding shares of Series E Junior Participating Preferred
Stock from the Quarterly Dividend Payment Date next preceding the date of issue
of such shares of Series E Junior Participating Preferred Stock, unless the date
of issue of such shares is prior to the record date for the first 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 E Junior Participating 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
E Junior Participating Preferred Stock in an amount less than the total amount
of such


                                       A-2

<PAGE>   38



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 of Directors may fix a record date for the determination of holders of
shares of Series E Junior Participating Preferred Stock entitled to receive
payment of a dividend or distribution declared thereon, which record date shall
be no more than 60 days prior to the date fixed for the payment thereof.

                  3.       Voting Rights. The holders of shares of Series E 
Junior Participating Preferred Stock shall have the following voting rights:

                           (A)  Each share of Series E Junior Participating
Preferred Stock shall entitle the holder thereof to a number of votes equal to
the Adjustment Number on all matters submitted to a vote of the stockholders of
the Corporation.

                           (B)  Except as required by law and by Section 10
hereof, holders of Series E Junior Participating 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.

                  4.       Certain Restrictions.

                           (A)  Whenever quarterly dividends or other dividends
or distributions payable on the Series E Junior Participating 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
E Junior Participating Preferred Stock outstanding shall have been paid in full,
the Corporation shall not:

                                (i)     declare or pay dividends on, make any
other distributions on, or redeem or purchase or otherwise acquire for
consideration any shares of stock ranking junior (either as to dividends or upon
liquidation, dissolution or winding up) to the Series E Junior Participating
Preferred Stock;

                                (ii)    declare or pay dividends on 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 E
Junior Participating Preferred Stock, except dividends paid ratably on the
Series E Junior Participating 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; or

                                (iii)   purchase or otherwise acquire for 
consideration any shares of Series E Junior Participating Preferred Stock, or
any shares of stock ranking on a parity with the Series E Junior Participating
Preferred Stock, except in accordance with a purchase offer made in writing or
by publication (as determined by the Board of Directors) to all holders of
Series E Junior Participating Preferred Stock, or to such holders and holders of
any such shares ranking on a parity therewith, upon such terms as the Board of
Directors, after consideration of the respective annual dividend rates and other
relative rights and preferences of the respective series and classes, shall



                                       A-3

<PAGE>   39



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.

                  5.       Reacquired Shares. Any shares of Series E Junior
Participating Preferred Stock purchased or otherwise acquired by the Corporation
in any manner whatsoever shall be retired promptly after the acquisition
thereof. All such shares shall upon their retirement become authorized but
unissued shares of Preferred Stock and may be reissued as part of a new series
of Preferred Stock to be created by resolution or resolutions of the Board of
Directors, subject to any conditions and restrictions on issuance set forth
herein.

                  6.       Liquidation, Dissolution or Winding Up.

                           (A)  Upon any liquidation, dissolution or winding up
of the Corporation, voluntary or otherwise, no distribution shall be made to the
holders of shares of stock ranking junior (either as to dividends or upon
liquidation, dissolution or winding up) to the Series E Junior Participating
Preferred Stock unless, prior thereto, the holders of shares of Series E Junior
Participating Preferred Stock shall have received an amount per share (the
"Series E Liquidation Preference") equal to the greater of (i) $1,000.00 plus an
amount equal to accrued and unpaid dividends and distributions thereon, whether
or not declared, to the date of such payment, or (ii) the Adjustment Number
times the per share amount of all cash and other property to be distributed in
respect of the Common Stock upon such liquidation, dissolution or winding up of
the Corporation.

                           (B)  In the event, however, that there are not
sufficient assets available to permit payment in full of the Series E
Liquidation Preference and the liquidation preferences of all other classes and
series of stock of the Corporation, if any, that rank on a parity with the
Series E Junior Participating Preferred Stock in respect thereof, then the
assets available for such distribution shall be distributed ratably to the
holders of the Series E Junior Participating Preferred Stock and the holders of
such parity shares in proportion to their respective liquidation preferences.

                           (C)  Neither the merger or consolidation of the
Corporation into or with another corporation nor the merger or consolidation of
any other corporation into or with the Corporation shall be deemed to be a
liquidation, dissolution or winding up of the Corporation within the meaning of
this Section 6.

                  7.       Consolidation, Merger, Etc. In case the Corporation
shall enter into any consolidation, merger, combination or other transaction in
which the outstanding 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 E Junior Participating Preferred Stock shall at the same
time be similarly exchanged or changed in an amount per share equal to the
Adjustment Number



                                       A-4

<PAGE>   40



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 exchanged.

                  8.       No Redemption. Shares of Series E Junior 
Participating Preferred Stock shall not be subject to redemption by the Company.

                  9.       Ranking. The Series E Junior Participating Preferred
Stock shall rank junior to all other series of the Preferred Stock as to the
payment of dividends and as to the distribution of assets upon liquidation,
dissolution or winding up, unless the terms of any such series shall provide
otherwise, and shall rank senior to the Common Stock as to such matters.

                  10.      Amendment. At any time that any shares of Series E
Junior Participating Preferred Stock are outstanding, the Certificate of
Incorporation 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 E Junior Participating Preferred Stock so as to affect them adversely
without the affirmative vote of the holders of two-thirds of the outstanding
shares of Series E Junior Participating Preferred Stock, voting separately as a
class.

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

                  IN WITNESS WHEREOF, the undersigned has executed this
Certificate this __ day of April, 1998.

                                            HARKEN ENERGY CORPORATION



                                            By:
                                               -------------------------------- 
                                                 Bruce N. Huff
                                                 President and Chief Operating 
                                                 Officer



                                       A-5


<PAGE>   41


                                                                       Exhibit B


                            Form of Right Certificate

Certificate No. R-______

              NOT EXERCISABLE AFTER APRIL 6, 2008 OR EARLIER IF
              REDEMPTION OR EXCHANGE OCCURS. THE RIGHTS ARE SUBJECT TO
              REDEMPTION AT $.01 PER RIGHT AND TO EXCHANGE ON THE
              TERMS SET FORTH IN THE RIGHTS AGREEMENT. UNDER CERTAIN
              CIRCUMSTANCES, AS SET FORTH IN THE RIGHTS AGREEMENT,
              RIGHTS OWNED BY OR TRANSFERRED TO ANY PERSON WHO IS OR
              BECOMES AN ACQUIRING PERSON (AS DEFINED IN THE RIGHTS
              AGREEMENT) AND CERTAIN TRANSFEREES THEREOF WILL BECOME
              NULL AND VOID AND WILL NO LONGER BE TRANSFERABLE.


                                RIGHT CERTIFICATE

                            HARKEN ENERGY CORPORATION

                  This certifies that ____________________________ or registered
assigns, is the registered owner of the number of Rights set forth above, each
of which entitles the owner thereof, subject to the terms, provisions and
conditions of the Rights Agreement, dated as of April 6, 1998, as the same may
be amended from time to time (the "Rights Agreement"), between Harken Energy
Corporation, a Delaware corporation (the "Company"), and ChaseMellon Shareholder
Services L.L.C., as Rights Agent (the "Rights Agent"), to purchase from the
Company at any time after the Distribution Date (as such term is defined in the
Rights Agreement) and prior to 5:00 P.M., New York City time, on April 6, 2008
at the office or agency of the Rights Agent designated for such purpose, or of
its successor as Rights Agent, one one-thousandth of a fully paid non-assessable
share of Series E Junior Participating Preferred Stock, par value $1.00 per
share (the "Preferred Stock"), of the Company at a purchase price of $35.00 per
one one-thousandth of a share of Preferred Stock (the "Purchase Price"), upon
presentation and surrender of this Right Certificate with the Form of Election
to Purchase duly executed. The number of Rights evidenced by this Rights
Certificate (and the number of one one-thousandths 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 April 6, 1998,
based on the Preferred Stock as constituted at such date. As provided in the
Rights Agreement, the Purchase Price, the number of one one-thousandths of a
share of Preferred Stock (or other securities or property) which may be
purchased upon the exercise of the Rights and the number of Rights evidenced by
this Right Certificate are subject to modification and adjustment upon the
happening of certain events.

                                       B-1

<PAGE>   42




                  This Right 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 Right Certificates.
Copies of the Rights Agreement are on file at the principal executive offices of
the Company and the above-mentioned office or agency of the Rights Agent. The
Company will mail to the holder of this Right Certificate a copy of the Rights
Agreement without charge after receipt of a written request therefor.

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

                  Subject to the provisions of the Rights Agreement, the Rights
evidenced by this Certificate (i) may be redeemed by the Company at a redemption
price of $.01 per Right or (ii) may be exchanged in whole or in part for shares
of the Company's Common Stock, par value $.01 per share, or shares of Preferred
Stock.

                  No fractional shares of Preferred Stock or Common Stock will
be issued upon the exercise or exchange of any Right or Rights evidenced hereby
(other than fractions of Preferred Stock 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 depository receipts), but in lieu thereof a cash
payment will be made, as provided in the Rights Agreement.

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

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


                                       B-2

<PAGE>   43



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


                                        HARKEN ENERGY CORPORATION



                                        By:
                                           ------------------------------------ 
                                                      

ATTEST:




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


Countersigned:


CHASEMELLON SHAREHOLDER SERVICES L.L.C., as Rights Agent




By:
   ---------------------------------  




                                       B-3

<PAGE>   44



                    Form of Reverse Side of Right Certificate

                               FORM OF ASSIGNMENT

                (To be executed by the registered holder if such
                holder desires to transfer the Right Certificate)

                  FOR VALUE RECEIVED __________________________ hereby sells,
assigns and transfers unto
___________________________________________________________________ (Please
print name and address of transferee) _________________________________________
Rights represented by this Right Certificate, together with all right, title and
interest therein, and does hereby irrevocably constitute and appoint
_____________________ Attorney, to transfer said Rights on the books of the
within-named Company, with full power of substitution.

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


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

Signature Guaranteed:


                  Signatures must be guaranteed by a bank, trust company,
broker, dealer or other eligible institution participating in a recognized
signature guarantee medallion program.

 ................................................................................
                                (To be completed)

                  The undersigned hereby certifies that the Rights evidenced by
this Right Certificate are not beneficially owned by, were not acquired by the
undersigned from, and are not being assigned to an Acquiring Person or an
Affiliate or Associate thereof (as defined in the Rights Agreement).



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




                                       B-4

<PAGE>   45



              Form of Reverse Side of Right Certificate - continued

                          FORM OF ELECTION TO PURCHASE

                  (To be executed if holder desires to exercise
                  Rights represented by the Rights Certificate)

To HARKEN ENERGY CORPORATION:

                  The undersigned hereby irrevocably elects to exercise ________
Rights represented by this Right Certificate to purchase the shares of Preferred
Stock (or other securities or property) issuable upon the exercise of such
Rights and requests that certificates for such shares of Preferred Stock (or
such other securities) be issued in the name of:


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


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


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

Please insert social security
or other identifying number


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


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


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

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

        (Signature must conform to holder specified on Right Certificate)

Signature Guaranteed:

                  Signature must be guaranteed by a bank, trust company, broker,
dealer or other eligible institution participating in a recognized signature
guarantee medallion program.




                                       B-5

<PAGE>   46



              Form of Reverse Side of Right Certificate - continued


--------------------------------------------------------------------------------
                                (To be completed)

                  The undersigned certifies that the Rights evidenced by this
Right Certificate are not beneficially owned by, and were not acquired by the
undersigned from, an Acquiring Person or an Affiliate or Associate thereof (as
defined in the Rights Agreement).

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


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


                                     NOTICE

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

                  In the event the certification set forth above in the Form of
Assignment or the Form of Election to Purchase, as the case may be, is not
completed, such Assignment or Election to Purchase will not be honored.





                                       B-6

<PAGE>   47


                                                                       Exhibit C



              UNDER CERTAIN CIRCUMSTANCES, AS SET FORTH IN THE RIGHTS
              AGREEMENT, RIGHTS OWNED BY OR TRANSFERRED TO ANY PERSON
              WHO IS OR BECOMES AN ACQUIRING PERSON (AS DEFINED IN THE
              RIGHTS AGREEMENT) AND CERTAIN TRANSFEREES THEREOF WILL 
              BECOME NULL AND VOID AND WILL NO LONGER BE TRANSFERABLE.

                          SUMMARY OF RIGHTS TO PURCHASE
                          SHARES OF PREFERRED STOCK OF
                            HARKEN ENERGY CORPORATION

                  On April 6, 1998, the Board of Directors of Harken Energy
Corporation (the "Company") declared a dividend of one preferred share purchase
right (a "Right") for each outstanding share of common stock, par value $.01 per
share, of the Company (the "Common Stock"). The dividend is payable on April 17,
1998 (the "Record Date") to the stockholders of record on that date. Each Right
entitles the registered holder to purchase from the Company one one-thousandth
of a share of Series E Junior Participating Preferred Stock, par value $1.00 per
share, of the Company (the "Preferred Stock") at a price of $35.00 per one
one-thousandth of a share of Preferred Stock (the "Purchase Price"), subject to
adjustment. The description and terms of the Rights are set forth in a Rights
Agreement dated as of April 6, 1998, as the same may be amended from time to
time (the "Rights Agreement"), between the Company and ChaseMellon Shareholder
Services L.L.C., as Rights Agent (the "Rights Agent").

                  Until the earlier to occur of (i) 10 days following a public
announcement that a person or group of affiliated or associated persons (with
certain exceptions, an "Acquiring Person") has acquired beneficial ownership of
15% or more of the outstanding shares of Common Stock or (ii) 10 business days
(or such later date as may be determined by action of the Board of Directors
prior to such time as any person or group of affiliated persons becomes an
Acquiring Person) following the commencement of, or announcement of an intention
to make, a tender offer or exchange offer the consummation of which would result
in the beneficial ownership by a person or group of 15% or more of the
outstanding shares of Common Stock (the earlier of such dates being called the
"Distribution Date"), the Rights will be evidenced, with respect to any of the
Common Stock certificates outstanding as of the Record Date, by such Common
Stock certificate together with a copy of this Summary of Rights.

                  The Rights Agreement provides that, until the Distribution
Date (or earlier expiration of the Rights), the Rights will be transferred with
and only with the Common Stock. Until the Distribution Date (or earlier
expiration of the Rights), new Common Stock certificates issued after the Record
Date upon transfer or new issuances of Common Stock will contain a notation
incorporating the Rights Agreement by reference. Until the Distribution Date (or
earlier expiration of the Rights), the surrender for transfer of any
certificates for shares of Common Stock outstanding

            
                                       C-1

<PAGE>   48



as of the Record Date, even without such notation or a copy of this Summary of
Rights, will also constitute the transfer of the Rights associated with the
shares of Common Stock represented by such certificate. As soon as practicable
following the Distribution Date, separate certificates evidencing the Rights
("Right Certificates") will be mailed to holders of record of the Common Stock
as of the close of business on the Distribution Date and such separate Right
Certificates alone will evidence the Rights.

                  The Rights are not exercisable until the Distribution Date.
The Rights will expire on April 6, 2008 (the "Final Expiration Date"), unless
the Final Expiration Date is advanced or extended or unless the Rights are
earlier redeemed or exchanged by the Company, in each case as described below.

                  The Purchase Price payable, and the number of shares of
Preferred Stock or other securities or property issuable, upon exercise of the
Rights is 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) upon the grant to holders of the Preferred Stock
of certain rights or warrants to subscribe for or purchase Preferred Stock at a
price, or securities convertible into Preferred Stock with a conversion price,
less than the then-current market price 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 or dividends payable in
Preferred Stock) or of subscription rights or warrants (other than those
referred to above).

                  The number of outstanding Rights is subject to adjustment in
the event of a stock dividend on the Common Stock payable in shares of Common
Stock or subdivisions, consolidations or combinations of the Common Stock
occurring, in any such case, prior to the Distribution Date.

                  Shares of Preferred Stock purchasable upon exercise of the
Rights will not be redeemable. Each share of Preferred Stock will be entitled,
when, as and if declared, to a minimum preferential quarterly dividend payment
of $10.00 per share but will be entitled to an aggregate dividend of 1000 times
the dividend declared per share of Common Stock. In the event of liquidation,
dissolution or winding up of the Company, the holders of the Preferred Stock
will be entitled to a minimum preferential payment of $1,000.00 per share (plus
any accrued but unpaid dividends) but 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.
Finally, in the event of any merger, consolidation or other transaction in which
outstanding shares of Common Stock are converted 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 the one one-thousandth interest in a
share of Preferred Stock purchasable upon exercise of each Right should
approximate the value of one share of Common Stock.


                                       C-2

<PAGE>   49



                  In the event that any person or group of affiliated or
associated persons becomes an Acquiring Person, each holder of a Right, other
than Rights beneficially owned by the Acquiring Person (which will thereupon
become void), will thereafter have the right to receive upon exercise of a Right
that number of shares of Common Stock having a market value of two times the
exercise price of the Right.

                  In the event that, after a person or group has become an
Acquiring Person, the Company is acquired in a merger or other business
combination transaction or 50% or more of its consolidated assets or earning
power are sold, proper provisions will be made so that each holder of a Right
(other than Rights beneficially owned by an Acquiring Person which will have
become void) will thereafter have the right to receive upon the exercise of a
Right that number of shares of common stock of the person with whom the Company
has engaged in the foregoing transaction (or its parent) that at the time of
such transaction have a market value of two times the exercise price of the
Right.

                  At any time after any person or group becomes an Acquiring
Person and prior to the earlier of one of the events described in the previous
paragraph or the acquisition by such Acquiring Person of 50% or more of the
outstanding shares of Common Stock, the Board of Directors of the Company may
exchange the Rights (other than Rights owned by such Acquiring Person which will
have become void), in whole or in part, for shares of Common Stock or Preferred
Stock (or a series of the Company's preferred stock having equivalent rights,
preferences and privileges), at an exchange ratio of one share of Common Stock,
or a fractional share of Preferred Stock (or other preferred stock) equivalent
in value thereto, per Right.

                  With certain exceptions, no adjustment in the Purchase Price
will be required until cumulative adjustments require an adjustment of at least
1% in such Purchase Price. No fractional shares of Preferred Stock or Common
Stock will be issued (other than fractions of Preferred Stock 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), and in lieu
thereof an adjustment in cash will be made based on the current market price of
the Preferred Stock or the Common Stock.

                  At any time prior to the time an Acquiring Person becomes
such, the Board of Directors of the Company may redeem the Rights in whole, but
not in part, at a price of $.01 per Right (the "Redemption Price"). The
redemption of the Rights may be made effective at such time, on such basis and
with such conditions as the Board of Directors in its sole discretion may
establish. Immediately upon any redemption of the Rights, the right to exercise
the Rights will terminate and the only right of the holders of Rights will be to
receive the Redemption Price.

                  For so long as the Rights are then redeemable, the Company
may, except with respect to the redemption price, amend the Rights Agreement in
any manner. After the Rights are no longer redeemable, the Company may, except
with respect to the redemption price, amend the Rights Agreement in any manner
that does not adversely affect the interests of holders of the Rights.


                                       C-3

<PAGE>   50


                  Until a Right is exercised or exchanged, 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.

                  A copy of the Rights Agreement has been filed with the
Securities and Exchange Commission as an Exhibit to a Registration Statement on
Form 8-A dated April 6, 1998. 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, as the same may be amended from time to time, which is hereby
incorporated herein by reference.



                                       C-4