<PAGE>   1
                       FIRST AMENDMENT TO RIGHTS AGREEMENT

         THIS AMENDMENT (this "Amendment"), dated as of July 30, 2001 to the
Rights Agreement, dated as of July 26, 2001 (the "Rights Agreement"), by and
between Kerr-McGee Holdco, Inc., a Delaware corporation (the "Company"), and UMB
Bank, N.A., as Rights Agent (the "Rights Agent").

                                 R E C I T A L S

         WHEREAS, the Company and the Rights Agent have heretofore executed and
entered into the Rights Agreement;

         WHEREAS, pursuant to Section 27 of the Rights Agreement, the Company
may from time to time supplement or amend the Rights Agreement in accordance
with the provisions thereof; and

         WHEREAS, the Board of Directors has determined that it is in the best
interest of the Company and its stockholders to amend the Rights Agreement as
set forth below.

                                A G R E E M E N T

         NOW THEREFORE, the Company hereby amends the Rights Agreement as
follows:

         1. Section 1(n) of the Rights Agreement is hereby amended by deleting
the words "Certificate of Designation" in the third line thereof and by
inserting the text "Amended and Restated Certificate of Incorporation".

         2. Exhibit A to the Rights Agreement is hereby amended by deleting the
text of such exhibit in its entirety and replacing it with Exhibit A to this
Amendment.

         3. This Amendment 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.

         4. This Amendment may be executed in any number of counterparts, each
of which shall be an original, but such counterparts shall together constitute
one and the same instrument.

         5. Terms not defined herein shall, unless the context otherwise
requires, have the meanings assigned to such terms in the Rights Agreement.
<PAGE>   2
                                                                               2

         6. In all respects not inconsistent with the terms and provisions of
this Amendment, the Rights Agreement is hereby ratified, adopted, approved and
confirmed. In executing and delivering this Amendment, the Rights Agent shall be
entitled to all the privileges and immunities afforded to the Rights Agreement
under the terms and conditions of the Rights Agreement.

         [The remainder of this page has been intentionally left blank]
<PAGE>   3
                                                                               3

         IN WITNESS WHEREOF, this Amendment has been duly executed by the
Company and the Rights Agent as of the day and year first written above.

                                       KERR-McGEE HOLDCO, INC.


                                       By:
                                             GREGORY F. PILCHER
                                       -----------------------------------------
                                       Name:  Gregory F. Pilcher
                                       Title: Senior Vice President,
                                              Secretary and General Counsel


                                       UMB BANK, N.A.


                                       By:
                                              K. SCOTT MATHEWS
                                       -----------------------------------------
                                       Name:  K. Scott Mathews
                                       Title: Vice President
<PAGE>   4
                                                                       Exhibit A

                              AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                             KERR-MCGEE HOLDCO, INC.

(ORIGINALLY INCORPORATED ON MAY 11, 2001 UNDER THE NAME KING HOLDCO, INC. THIS
AMENDED AND RESTATED CERTIFICATE OF INCORPORATION WAS DULY ADOPTED IN ACCORDANCE
WITH SECTIONS 242 AND 245 OF THE GENERAL CORPORATION LAW OF THE STATE OF
DELAWARE)

         FIRST:   The name of the corporation is:

                             KERR-MCGEE CORPORATION

         SECOND: The registered office of the corporation in the State of
Delaware is located at No. 1209 Orange Street, in the City of Wilmington, County
of New Castle. The name and address of its resident agent is The Corporation
Trust Company, No. 1209 Orange Street, Wilmington, Delaware 19801.

         THIRD: The purpose of the corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware.

         FOURTH: (1) The total number of shares of all classes of stock which
the corporation shall have the authority to issue is 340,000,000, of which
40,000,000 shares shall be preferred stock, without par value, and 300,000,000
shall be common stock of the par value of $1.00 per share.

         Each holder of common stock, as such, shall be entitled to one vote for
each share of common stock held of record by such holder on all matters on which
stockholders generally are entitled to vote; provided, however, that, except as
otherwise required by law, holders of common stock, as such, shall not be
entitled to vote on any amendment to this certificate of incorporation
(including any certificate of designations relating to any series of preferred
stock) that relates solely to the terms of one or more outstanding series of
preferred stock if the holders of such affected series are entitled, either
separately or together with the holders of one or more other such series, to
vote thereon pursuant to this certificate of incorporation (including any
certificate of designations relating to any series of preferred stock) or
pursuant to the General Corporation Law of the State of Delaware.

         (2) The preferred stock may be issued from time to time in one or more
series. The resolution or resolutions of the Board of Directors providing for
the issue of


                                       1
<PAGE>   5
shares of a particular series shall fix, subject to applicable laws and
provisions of this certificate of incorporation, the voting power, designation,
preferences and relative, participating, optional or other special rights, and
qualifications, limitations or restrictions of the shares of such series. The
authority of the Board of Directors with respect to each series shall include,
but not be limited to, determination of the following:

                  i)       the number of shares constituting such series,
                           including the authority to increase or decrease such
                           number, and the distinctive designation of such
                           series;

                  ii)      the rate of dividends payable on shares of such
                           series, the dates on which such dividends shall be
                           paid, and whether such dividends shall be cumulative
                           or noncumulative;

                  iii)     the full or limited voting power, if any, for such
                           series and the terms and conditions under which such
                           voting power may be exercised;

                  iv)      the right, if any, of the corporation to redeem
                           shares of such series and the terms and conditions of
                           such redemption;

                  v)       the obligations, if any, of the corporation to retire
                           shares of such series pursuant to a retirement or
                           sinking fund of a similar nature or otherwise and the
                           terms and conditions of such obligation;

                  vi)      the terms and conditions, if any, upon which the
                           shares of such series shall be convertible into
                           shares of stock of any other class or series
                           including the conversion rate and the term of
                           adjustment thereof, if any;

                  vii)     the amount which the holders of the shares of such
                           series shall be entitled to receive in case of a
                           liquidation, dissolution or winding up of the
                           corporation;

                  viii)    the relative priority of the shares of such series to
                           shares of other classes or series with respect to
                           dividends or upon the dissolution of or the
                           distribution of assets of the corporation; and

                  ix)      and other rights and qualifications, preferences and
                           limitations or restrictions of the shares of such
                           series;

                           so far as not inconsistent with the provisions of
                           this certificate of incorporation and to the full
                           extent now or hereafter permitted by the laws of the
                           State of Delaware.

         (3) Except as otherwise provided in this paragraph (3), no direct or
indirect purchase by the corporation from any Interested Stockholder (as
hereinafter defined) of shares of common stock of the corporation beneficially
owned by such Interested Stockholder for less than two years prior to the date
of such purchase shall be made at a per share price in excess of Fair Market
Value (as hereinafter defined) at the time of such purchase unless such


                                       2
<PAGE>   6
purchase is approved by the affirmative vote of not less than a majority of the
Voting Stock (as defined in Article THIRTEENTH) held by Disinterested
Stockholders (as hereinafter defined).

         The provisions of this paragraph (3) shall not apply to (i) any offer
to purchase made by the corporation which is made on the same terms and
conditions of the holders of all shares of common stock of the corporation, or
(ii) any open market purchases by the corporation of shares of its common stock
at prevailing market prices.

         The provisions of this paragraph (3) shall not be amended without the
affirmative vote of (a) not less than a majority of the Voting Stock entitled to
vote thereon and (b) not less than a majority of the Voting Stock entitled to
vote thereon held by Disinterested Stockholders.

         For purposes of this paragraph (3); I) the terms "INTERESTED
STOCKHOLDER" shall have the meaning of "Related Person" set forth in paragraph
(B)(3) of Article THIRTEENTH except that the percent of Voting Stock referred to
in clauses (a) and (b) of such definition shall be five percent (5%) rather than
ten percent (10%); (ii) the term "FAIR MARKET VALUE" shall have the meaning set
forth in paragraph (B)(9) of Article THIRTEENTH except that "Fair Market Value"
shall mean the highest sale price or bid quotation during the five-trading day
period preceding the date of the purchase of the stock; and (iii) the terms
"DISINTERESTED STOCKHOLDERS" means those holders of the Voting Stock, none of
which is an Interested Stockholder.

         (4)      SERIES B PREFERRED STOCK

                  SECTION 1. DESIGNATION AND AMOUNT. There shall be designated a
series of preferred stock as "Series B Junior Participating Preferred Stock"
(the "Series B Preferred Stock") and the number of shares constituting the
Series B Preferred Stock shall be 1,000,000. Such number of shares may be
increased or decreased by resolution of the Board of Directors; provided, that
no decrease shall reduce the number of shares of Series B Preferred Stock to a
number less than the number of shares then outstanding plus the number of shares
reserved for issuance upon the exercise of outstanding options, rights or
warrants or upon the conversion of any outstanding securities issued by the
corporation convertible into Series B Preferred Stock.

                  SECTION  2. DIVIDENDS AND DISTRIBUTIONS.

                  (A) Subject to the rights of the holders of any shares of any
series of preferred stock of the corporation (the "Preferred Stock") (or any
similar stock) ranking prior and superior to the Series B Preferred Stock with
respect to dividends, the holders of shares of Series B Preferred Stock, in
preference to the holders of common stock of the corporation (the "Common
Stock") and of any other stock of the corporation ranking junior to the Series B
Preferred Stock, 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 January, April, July, and October
in each year (each such date being referred to herein as a "Dividend Payment
Date"), commencing on the first Dividend Payment Date after the first issuance
of a share or fraction of a share of Series B Preferred Stock, in an amount per
share (rounded to the nearest cent) equal to the greater of (a) $1 or (b)
subject to the provision for adjustment hereinafter set forth, 100 times the
aggregate per share amount of all


                                       3
<PAGE>   7
cash dividends, and 100 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, declared on the Common Stock since the immediately
preceding Dividend Payment Date or, with respect to the first Dividend Payment
Date, since the first issuance of any share or fraction of a share of Series B
Preferred Stock. In the event the corporation shall at any time after July 9,
1996 declare or pay any dividend on the Common Stock payable in shares of Common
Stock, or effect a subdivision or combination or consolidation of the
outstanding shares of Common Stock (by reclassification or otherwise than by
payment of a dividend in shares of Common Stock) into a greater or lesser number
of shares of Common Stock, then in each such case the amount to which holders of
shares of Series B Preferred Stock were entitled immediately prior to such event
under clause (b) of the preceding sentence shall be adjusted by multiplying such
amount by a fraction, the numerator of which is the number of shares of Common
Stock outstanding immediately after such event and the denominator of which is
the number of shares of Common Stock that were outstanding immediately prior to
such event.

                  (B) The corporation shall declare a dividend or distribution
on the Series B Preferred Stock as provided in paragraph (A) of this Section
immediately after it declares a dividend or distribution on the Common Stock
(other than a dividend payable in shares of Common Stock); provided that, in the
event no dividend or distribution shall have been declared on the Common Stock
during the period between any Dividend Payment Date and the next subsequent
Dividend Payment Date, a dividend of $1 per share on the Series B Preferred
Stock shall nevertheless be payable, when, as and if declared, on such
subsequent Dividend Payment Date.

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

                  SECTION 3. VOTING RIGHTS. The holders of shares of Series B
Preferred Stock shall have the following voting rights:

                  (A) Subject to the provision for adjustment hereinafter set
         forth and except as otherwise provided in this certificate of
         incorporation or required by law, each share of Series B Preferred
         Stock shall entitle the holder thereof to 100 votes on


                                       4
<PAGE>   8
         all matters upon which the holders of the Common Stock of the
         corporation are entitled to vote. In the event the corporation shall at
         any time after July 9, 1996 declare or pay any dividend on the Common
         Stock payable in shares of Common Stock, or effect a subdivision or
         combination or consolidation of the outstanding shares of Common Stock
         (by reclassification or otherwise than by payment of a dividend in
         shares of Common Stock) into a greater or lesser number of shares of
         Common Stock, then in each such case the number of votes per share to
         which holders of shares of Series B Preferred Stock were entitled
         immediately prior to such event shall be adjusted by multiplying such
         number by a fraction, the numerator of which is the number of shares of
         Common Stock outstanding immediately after such event and the
         denominator of which is the number of shares of Common Stock that were
         outstanding immediately prior to such event.

                  (B) Except as otherwise provided herein, in this certificate
         of incorporation or in any other certificate of designations creating a
         series of Preferred Stock or any similar stock, and except as otherwise
         required by law, the holders of shares of Series B Preferred Stock and
         the holders of shares of Common Stock and any other capital stock of
         the corporation having general voting rights shall vote together as one
         class on all matters submitted to a vote of stockholders of the
         corporation.

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

                  SECTION 4. CERTAIN RESTRICTIONS.

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

                           (i) declare or pay dividends, or make any other
                  distributions, on any shares of stock ranking junior (as to
                  dividends) to the Series B Preferred Stock;

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

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


                                       5
<PAGE>   9
                  junior (as to dividends and upon dissolution, liquidation or
                  winding up) to the Series B Preferred Stock or rights,
                  warrants or options to acquire such junior stock;

                           (iv) redeem or purchase or otherwise acquire for
                  consideration any shares of Series B Preferred Stock, or any
                  shares of stock ranking on a parity (either as to dividends or
                  upon liquidation, dissolution or winding up) with the Series B
                  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 such shares 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
                  determine in good faith will result in fair and equitable
                  treatment among the respective series or classes.

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

                  SECTION 5. REACQUIRED SHARES. Any shares of Series B Preferred
Stock purchased or otherwise acquired by the corporation in any manner
whatsoever shall be retired and cancelled promptly after the acquisition
thereof. All such shares shall upon their 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.

                  SECTION 6. LIQUIDATION, DISSOLUTION OR WINDING UP. Upon any
liquidation, dissolution or winding up of the corporation, no distribution shall
be made (A) to the holders of the Common Stock or of shares of any other stock
of the corporation ranking junior, upon liquidation, dissolution or winding up,
to the Series B Preferred Stock unless, prior thereto, the holders of shares of
Series B Preferred Stock shall have received $100 per share, plus an amount
equal to accrued and unpaid dividends and distributions thereon, whether or not
earned or declared, to the date of such payment, provided that the holders of
shares of Series B Preferred Stock shall be entitled to receive an aggregate
amount per share, subject to the provision for adjustment hereinafter set forth,
equal to 100 times the aggregate amount to be distributed per share to holders
of shares of Common Stock, or (B) to the holders of shares of stock ranking on a
parity upon liquidation, dissolution or winding up with the Series B Preferred
Stock, except distributions made ratably on the Series B Preferred Stock and all
such parity stock in proportion to the total amounts to which the holders of all
such shares are entitled upon such liquidation, dissolution or winding up. In
the event, however, that there are not sufficient assets available to permit
payment in full of the Series B 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 B Preferred Stock in respect thereof, then
the assets available for such distribution shall be distributed ratably to the
holders of the Series B Preferred Stock and the holders of such parity shares in
the proportion to their respective liquidation preferences. In the event the
corporation shall at any time after July 9,


                                       6
<PAGE>   10
1996 declare or pay any dividend on the Common Stock payable in shares of Common
Stock, or effect a subdivision or combination or consolidation of the
outstanding shares of Common Stock (by reclassification or otherwise than by
payment of a dividend in shares of Common Stock) into a greater or lesser number
of shares of Common Stock, then in each such case the aggregate amount to which
holders of shares of Series B Preferred Stock were entitled immediately prior to
such event under the proviso in clause (A) of the preceding sentence shall be
adjusted by multiplying such amount by a fraction the numerator of which is the
number of shares of Common Stock outstanding immediately after such event and
the denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

                  SECTION 7. CONSOLIDATION, MERGER, ETC. In case the corporation
shall enter into any consolidation, merger, combination or other transaction in
which the shares of Common Stock are converted into, exchanged for or changed
into other stock or securities, cash and/or any other property, then in any such
case each share of Series B Preferred Stock shall at the same time be similarly
converted into, exchanged for or changed into an amount per share (subject to
the provision for adjustment hereinafter set forth) equal to 100 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 converted, exchanged or converted. In the event the corporation shall at any
time after July 9, 1996 declare or pay any dividend on the Common Stock payable
in shares of Common Stock, or effect a subdivision or combination or
consolidation of the outstanding shares of Common Stock (by reclassification or
otherwise than by payment of a dividend in shares of Common Stock) into a
greater or lesser number of shares of Common Stock, then in each such case the
amount set forth in the preceding sentence with respect to the conversion,
exchange or change of shares of Series B Preferred Stock shall be adjusted by
multiplying such amount by a fraction, the numerator of which is the number of
shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

                  SECTION 8. NO REDEMPTION. The shares of Series B Preferred
Stock shall not be redeemable from any holder.

                  SECTION 9. RANK. The Series B Preferred Stock shall rank, with
respect to the payment of dividends and the distribution of assets upon
liquidation, dissolution or winding up of the corporation, junior to all other
series of Preferred Stock and senior to the Common Stock.

                  SECTION 10. AMENDMENT. If any proposed amendment to this
certificate of incorporation would alter, change or repeal any of the
preferences, powers or special rights given to the Series B Preferred Stock so
as to affect the Series B Preferred Stock adversely, then the holders of the
Series B Preferred Stock shall be entitled to vote separately as a class upon
such amendment, and the affirmative vote of two-thirds of the outstanding shares
of the Series B Preferred Stock, voting separately as a class, shall be
necessary for the adoption thereof, in addition to such other vote as may be
required by the General Corporation Law of the State of Delaware.

                                       7
<PAGE>   11
                  SECTION 11. FRACTIONAL SHARES. Series B 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 B Preferred Stock.

         (5) PREEMPTIVE RIGHTS. Neither the holders of preferred stock nor the
holders of common stock shall have any preemptive rights, and the corporation
shall have the right to issue and sell to any person or persons any shares of
its capital stock or any option rights or any securities having conversion or
option rights, without first offering such shares, rights or securities to any
holders of preferred stock or common stock.

         FIFTH: (1) The business and affairs of the corporation shall be managed
by a Board of Directors. The number of directors shall be fixed from time to
time by resolution adopted by affirmative vote of the majority of the Board of
Directors, but shall not be fixed at a number less than three.

                  The directors shall be classified, with respect to the time
for which they severally hold office, into three classes, as nearly equal in
number as possible, with the term of the first class to expire at the 1999
annual meeting of the stockholders, the term of office of the second class to
expire at the 2000 annual meeting of the stockholders, and the term of office of
the third class to expire at the 2001 annual meeting of the stockholders, with
the members of each class to hold office until their successors are elected and
qualified. At each succeeding annual meeting of the stockholders of the
corporation, the successors to the class of directors whose term expires at the
meeting shall be elected to hold office for a term expiring st the annual
meeting of the stockholders held in the third year following the year of their
election.

                  Newly created directorships resulting from any increase in the
number of directors and any vacancies on the Board of Directors resulting from
death, resignation, disqualification, removal or other cause shall be filled by
the affirmative vote of a majority of the remaining directors then in office,
even though less than a quorum of the Board of Directors. Any director elected
in accordance with the preceding sentence shall hold office for the remainder of
the full term of the class of directors in which the new directorship was
created or the vacancy occurred until such director's successor shall have been
elected and qualified. No decrease in the number of directors constituting the
Board of Directors shall shorten the term of any incumbent director.

                  Directors may be removed only for cause, and then only by the
affirmative vote of at least 75 percent in voting power of all shares of the
corporation entitled to vote generally in the election of directors, voting as a
single class.

         (2) Notwithstanding the foregoing, whenever the holders of any one or
more series of preferred stock issued by the corporation shall have the right,
voting separately as a series or separately as a class with one or more such
other series, to elect directors at an annual or special meeting of
stockholders, the election, term of office, removal, filling of vacancies and
other features of such directorships shall be governed by the terms of this
certificate of incorporation (including any certificate of designations relating
to any series of preferred


                                       8
<PAGE>   12
stock) applicable thereto, and such directors so elected shall not be divided
into classes pursuant to this Article FIFTH unless expressly provided by such
terms.

         SIXTH: The Board of Directors shall be authorized to make, amend,
alter, change, add to or repeal the By-Laws of the corporation in any manner not
inconsistent with the laws of the State of Delaware, subject to the power of the
stockholders to amend, alter, change, add to or repeal the By-Laws made by the
Board of Directors. Notwithstanding anything contained in this certificate of
incorporation to the contrary, the affirmative vote of the holders of at least
75 percent in voting power of all the shares of the corporation entitled to vote
generally in the election of directors, voting together as a single class, shall
be required in order for the stockholders to alter, amend or repeal any
provision of the By-Laws which is to the same effect as Article FIFTH, Article
SIXTH, and Article FOURTEENTH of this certificate of incorporation or to adopt
any provision inconsistent therewith.

         SEVENTH: (1) (a) The corporation shall, to the full extent permitted by
the Laws of the State of Delaware as then in effect or, if less stringent, in
effect on December 31, 1985 ("Delaware Law"), and as more fully described in the
By-Laws, indemnify any person (the "Indemnitee") made or threatened to be made a
party to any threatened, pending or completed action, suit or proceeding,
whether civil, criminal, administrative or investigative and whether or not by
or in the right of the corporation, by reason of the fact that the Indemnitee is
or was a director, officer or employee of the corporation or is or was serving
at the request of the corporation as a director, officer, employee, trustee,
partner, or other agent of any other enterprise or legal person (any such
action, suit or proceeding being herein referred to as a "Legal Action") against
all expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by the Indemnitee in connection with
such Legal Action or its investigation, defense or appeal (herein called
"Indemnified Expenses"), if the Indemnitee has met the standard of conduct
necessary under Delaware Law to permit such indemnification. Rights to
indemnification shall extend to the heirs, beneficiaries, administrators and
executors of any deceased Indemnitee.

                  For purposes of this Section, reference to "any other
enterprise or legal person" shall include employee benefit plans; references to
"fines" shall include any excise taxes assessed on a person with respect to an
employee benefit plan; and references to "serving at the request of the
corporation" shall include any service as a director, officer, employee or agent
of the corporation which imposes duties on, or involves services by, such
director, officer, employee, or agent with respect to an employee benefit plan,
its participants, or beneficiaries.

                  (b) The Indemnified Expenses shall be paid by the corporation
in advance as shall be appropriate to permit Indemnitee to defray such expenses
currently as incurred, provided the Indemnitee agrees in writing that in the
event it shall ultimately be determined as provided hereunder that Indemnitee
was not entitled to be indemnified, then Indemnitee shall promptly repay to the
corporation such amounts so paid.

                  (c) Any amendment, repeal or modification of this Article
SEVENTH, the corporation's By-Laws or any applicable provision of Delaware Law,
or any other instrument, which eliminates or diminishes the indemnification
rights provided for in this Article


                                       9
<PAGE>   13
SEVENTH shall be ineffective as against an Indemnitee with respect to any Legal
Action based upon actions taken or not taken by the Indemnitee prior to such
repeal or the adoption of such modification or amendment. The provisions of this
Article SEVENTH, Section (1) shall be applicable to all Legal Actions made or
commenced after the adoption hereof, whether arising from acts or omissions to
act occurring before or after its adoption. The provisions of this Article
SEVENTH, Section (1) shall be deemed to be a contract between the corporation
and each director or officer who serves in such capacity at any time while this
Article SEVENTH, Section (1) and the relevant provisions of Delaware Law and
other applicable law, if any, are in effect. If any provision of this Article
SEVENTH, Section (1) shall be found to be invalid or limited in application by
reason of any law or regulation, it shall not affect the validity of the
remaining provisions hereof. The rights of indemnification provided in this
Article SEVENTH, Section (1) shall neither be exclusive of, nor be deemed in
limitation of, any rights to which an officer, director, employee or agent may
otherwise be entitled or permitted by contract, this certificate of
incorporation, vote of stockholders or directors or otherwise, or as a matter of
law, both as to actions in such person's official capacity and actions in any
other capacity while holding such office, it being the policy of the corporation
that indemnification of any person whom the corporation is obligated to
indemnify pursuant to subsection (a) of this Article SEVENTH, Section (1) shall
be made to the fullest extent permitted by law.

                  (d) The corporation may purchase and maintain insurance on
behalf of any person described in subsection (a) of this Article SEVENTH,
Section (1) against any liability asserted against such person, whether or not
the corporation would have the power to indemnify such person against such
liability under the provisions of this Article SEVENTH, Section (1) or
otherwise.

         (2) To the full extent permitted by the General Corporation Law of the
State of Delaware as the same exists or may hereafter be amended, a director of
the corporation shall not be liable to the corporation or its stockholders for
monetary damages for breach of fiduciary duty as a director. No repeal,
amendment or modification of this Article, whether direct or indirect, shall
eliminate or reduce its effect with respect to any act or omission of a director
of the corporation occurring prior to such repeal, amendment or modification.

         EIGHTH: Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this corporation under
Section 291 of Title 8 of the Delaware Code or on the application of trustees in
dissolution or of any receiver or receivers appointed for this corporation under
Section 79 of Title 8 of the Delaware Code order a meeting of the creditors or
class of creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, to be summoned in such manner as the said court
directs. If a majority in number representing three-fourths in value of the
creditors or class of creditors, and/or of the stockholders or class of
stockholders of this corporation, as the case may be, agree to any compromise or
arrangement and to any reorganization of this corporation as a consequence of
such compromise or arrangement, the said compromise or arrangement and the said
reorganization shall, if sanctioned by the court to


                                       10
<PAGE>   14
which the said application has been made, be binding on all the creditors or
class of creditors, and/or on all the stockholders or class of stockholders, of
this corporation, as the case may be, and also on this corporation.

         NINTH:    [Reserved]

         TENTH:    [Reserved]

         ELEVENTH: [Reserved]

         TWELFTH:  [Reserved]

         THIRTEENTH: The vote of the stockholders of the corporation required to
approve any Business Transaction shall be as set forth in this Article
THIRTEENTH. Each capitalized term shall have the meaning ascribed to it in
Paragraph (B) of this Article.

         (A) Notwithstanding any provision of law or any other provision of this
certificate of incorporation or any agreement with any national securities
exchange or otherwise which might permit a lesser vote or no vote and in
addition to any affirmative vote required of the holders of any particular class
or series of Voting Stock by law or by this certificate of incorporation, the
affirmative vote of the holders of not less than 51% of the outstanding shares
of Voting Stock of the corporation beneficially owned by stockholders other than
the Related Person shall be required for the approval or authorization of any
Business Transaction; provided, however, that such 51% voting requirement shall
not be applicable to any Business Transaction, and such Business Transaction
shall require only such affirmative vote as is required by law, any other
provision of this certificate of incorporation, any preferred stock designation
or any agreement with any national securities exchange, if, in the case of a
Business Transaction that does not involve any cash or other consideration being
received by the stockholders of the corporation solely in respect of their
ownership of shares of Voting Stock of the corporation, the condition specified
in the following paragraph (1) is satisfied, or, in the case of any other
Business Transaction, the conditions specified in either of the following
paragraphs (1) and (2) are satisfied.

                  (1) The Continuing Directors at the time of such Business
         Transaction constitute at least a majority of the Board of Directors of
         the corporation and such Business Transaction shall have been approved
         by a majority vote of the Continuing Directors; or

                  (2)(a) The consideration to be received by holders of a
         particular class or series of outstanding Voting Stock (including
         common stock) shall be in cash or in the same form as was previously
         paid in order to acquire beneficially shares of such class or series of
         Voting Stock that are beneficially owned by the Related Person and, if
         the Related Person beneficially owns shares of any class or series of
         Voting Stock that were acquired with varying forms of consideration,
         the form of consideration to be received by holders of such class or
         series of Voting Stock shall be either cash or the form used to acquire
         beneficially the largest number of shares of such class or series of
         Voting Stock beneficially acquired by it prior to the Announcement
         Date; and


                                       11
<PAGE>   15
                  (b) The aggregate amount of the cash and the Fair Market Value
         as of the Consummation Date of any consideration other than cash to be
         received per share by holders of common stock in such Business
         Transaction shall be at least equal to the highest of the following (it
         being intended that the requirements of this clause (A)(2)(b) shall be
         required to be met with respect to all shares of common stock
         outstanding whether or not the Related Person has acquired any shares
         of the common stock):

                           i) If applicable, the highest per share price
                  (including any brokerage commissions, transfer taxes and
                  soliciting dealers' fees) paid in order to acquire any shares
                  of common stock beneficially owned by the Related Person which
                  were acquired beneficially by such Related Person (x) with in
                  the two-year period immediately prior to the Announcement Date
                  or (y) in the transaction in which it became a Related Person,
                  whichever is higher; or

                           ii) The Fair Market Value per share of common stock
                  on the Announcement Date or on the Determination Date,
                  whichever is higher; and

                  (c) The aggregate amount of the cash and the Fair Market Value
         as of the Consummation Date of any consideration other than cash to be
         received per share by holders of shares of any other class or series of
         Voting Stock, other than common stock, shall be at least equal to the
         highest of the following (it being intended that the requirements of
         this clause (A)(2)(c) shall be required to be met with respect to every
         class and series of such outstanding Voting Stock, whether or not the
         Related Person has previously acquired any shares of a particular class
         or series of Voting Stock):

                           i) If applicable, the highest per share price
                  (including any brokerage commissions, transfer taxes and
                  soliciting dealers' fees) paid in order to acquire any shares
                  of such class or series of Voting Stock beneficially owned by
                  the Related Person which were acquired beneficially by such
                  Related Person (x) with the two-year period immediately prior
                  to the Announcement Date or (y) in the transaction in which it
                  became a Related Person, whichever is higher;

                           ii) If applicable, the highest preferential amount
                  per share to which the holders of share of such class or
                  series of Voting Stock are entitled in the event of any
                  voluntary or involuntary liquidation, dissolution or winding
                  up of the corporation; or

                           iii) The Fair Market Value per share of such class or
                  series of Voting Stock on the Announcement Date or the
                  Determination Date, whichever is higher; and

                  (d) After such Related Person has become a Related Person and
         prior to the consummation of such Business Transaction:

                           i) Such Related Person shall not have become the
                  Beneficial Owner of any additional shares of Voting Stock of
                  the corporation, except as part of the


                                       12
<PAGE>   16
                  transaction in which it became a Related Person or upon
                  conversion of convertible securities acquired by it prior to
                  becoming a Related Person or as a result of a pro rata stock
                  dividend or stock split; and

                           ii) Such Related Person shall not have received the
                  benefit, directly or indirectly (except proportionately as a
                  stockholder), of any loans, advances, guarantees, pledges or
                  other financial assistance or tax credits or other tax
                  advantages provided by the corporation or any Subsidiary,
                  whether in anticipation of or in connection with such Business
                  Transaction or otherwise; and

                           iii) Such Related Person shall not have caused any
                  material change in the corporation's business or capital
                  structure, including, without limitation, the issuance of
                  shares of capital stock of the corporation to any third party;
                  and

                           iv) There shall have been (aa) no failure to declare
                  and pay at the regular date therefor any full quarterly
                  dividends (whether or not cumulative) on any outstanding
                  preferred stock, and (bb) no reduction in the annual rate of
                  dividends paid on common stock (after giving effect to any
                  reclassification, including any reverse stock split,
                  recapitalization, reorganization or similar transaction which
                  has the effect of enlarging or reducing the number of
                  outstanding shares of common stock), unless such failure or
                  reduction shall have been approved by a majority of the
                  Continuing Directors; and

                  (e) A proxy or information statement describing the proposed
         Business Transaction and complying with the requirements of the
         Securities Exchange Act of 1934 and the rules and regulations
         thereunder (or any subsequent provisions replacing such Act, rules and
         regulations), whether or not the corporation is then subject to such
         requirements, shall be mailed at least thirty (30) days prior to the
         consummation of such Business Transaction to the public stockholders of
         the corporation and shall contain at the front thereof in a prominent
         place (i) any recommendations as to the advisability (or
         inadvisability) of the Business Transaction which the Continuing
         Directors, if any, may choose to state and (ii) the opinion of a
         reputable national investment banking firm as to the fairness (or not)
         of such Business Transaction from the point of view of the remaining
         public stockholders of the corporation (such investment banking firm to
         be engaged solely on behalf of the remaining public stockholders, to be
         paid a reasonable fee for their services by the corporation upon
         receipt of such opinion, to be unaffiliated with such Related Person,
         and, if there are at the time any Continuing Directors, to be selected
         by a majority of the Continuing Directors).

         (B)      or purposes of this Article THIRTEENTH:

                  (1)      The term "BUSINESS TRANSACTION" shall mean:

                           (a) Any merger or consolidation of the corporation or
                  any Subsidiary with (i) any Related Person or (ii) any other
                  corporation or entity (whether or


                                       13
<PAGE>   17
                  not itself a Related Person) which is, or after such merger or
                  consolidation, would be, an Affiliate of a Related Person;

                           (b) Any sale, lease, exchange, mortgage, pledge,
                  transfer or other disposition (in one transaction or in a
                  series of transactions) to or with any Related Person or any
                  Affiliate of any Related Person of assets of the corporation
                  or any Subsidiary having an aggregate Fair Market Value of
                  $10,000,000 or more;

                           (c) The adoption of any plan or proposal for the
                  liquidation or dissolution of the corporation proposed by or
                  on behalf of a Related Person or any Affiliate of the Related
                  Person;

                           (d) The issuance of or transfer by the corporation or
                  any Subsidiary (in one transaction or in a series of related
                  transactions) of any securities of the corporation or any
                  Subsidiary to a Related Person, or any Affiliate of a Related
                  Person, in exchange for cash, securities or other property (or
                  a combination thereof) having a Fair Market Value of
                  $10,000,000 or more, other than the issuance of securities
                  upon the conversion of convertible securities of the
                  corporation or any Subsidiary which were not acquired by such
                  Related Person (or such Affiliate) from the corporation or a
                  Subsidiary;

                           (e) Any reclassification of securities (including any
                  reverse stock split), or recapitalization or reorganization of
                  the corporation, or any merger or consolidation of the
                  corporation with any of its Subsidiaries or any self tender
                  offer for or repurchase of securities of the corporation or
                  any Subsidiary by the corporation or any Subsidiary or any
                  other transaction (whether or not with or into or otherwise
                  involving a Related Person) which in any such case has the
                  effect, directly or indirectly, of increasing the
                  proportionate share of the outstanding shares of any class or
                  series of stock or securities convertible into stock of the
                  corporation or any Subsidiary which is directly or indirectly
                  beneficially owned by any Related Person or any Affiliate of
                  any Related Person;

                  (2) A "PERSON" shall mean any individual, firm, corporation,
         group (as such term is used in Rule 13d of the General Rules and
         Regulations under the Securities Exchange Act of 1934, as in effect on
         December 31, 1984) or other entity.

                  (3) "RELATED PERSON" shall mean any person (other than the
         corporation or any Subsidiary or any employee benefit plan of the
         corporation or any Subsidiary) who or which:

                           (a) Is the beneficial owner, directly or indirectly,
                  of more than ten percent of the combined voting power of the
                  then outstanding shares of Voting Stock; or

                                       14
<PAGE>   18
                           (b) Is an Affiliate of the corporation and at anytime
                  within the two-year period immediately prior to the date in
                  question was the beneficial owner, directly or indirectly, of
                  ten percent or more of the combined voting power of the then
                  outstanding shares of Voting Stock; or

                           (c) Is an assignee of or has otherwise succeeded to
                  the beneficial ownership of any shares of Voting Stock that
                  were at any time within the two-year period immediately prior
                  to the date in question beneficially owned by a Related
                  Person, if such assignment or succession shall have occurred
                  in the course of a transaction or series of transactions not
                  involving a public offering within the meaning of the
                  Securities Act of 1933.

                  (4)      A person shall be a "BENEFICIAL OWNER" of any Voting
                           Stock:

                           (a) Which such person or any of its Affiliates or
                  Associates beneficially owns, directly or indirectly; or

                           (b) which such person or any of its Affiliates or
                  Associates has (a) the right to acquire (whether or not such
                  right is exercisable immediately), pursuant to any agreement,
                  arrangement or understanding or upon the exercise of
                  conversion rights, exchange rights, warrants or options, or
                  otherwise, or (b) the right to vote or direct the vote
                  pursuant to any agreement, arrangement or understanding; or

                           (c) which are beneficially owned, directly or
                  indirectly, by any other person with which such person or any
                  of its Affiliates or Associates has any agreement, arrangement
                  or understanding for the purpose of acquiring, holding, voting
                  or disposing of any shares of Voting Stock.

                  (5) For the purposes of determining whether a person is a
         Related Person pursuant to Paragraph (B)(3) of this Article THIRTEENTH,
         the number of shares of Voting Stock deemed to be outstanding shall
         include shares deemed owned by such Related Person through application
         of Paragraph (B)(4) of this Article but shall not include any other
         shares of Voting Stock that may be issuable pursuant to any agreement,
         arrangement or understanding, or upon exercise of conversion rights,
         warrants or options, or otherwise.

                  (6) "AFFILIATE" and "ASSOCIATE" shall have the respective
         meanings ascribed to such terms in Rule 12b-2 of the General Rules and
         Regulations under the Securities Exchange Act of 1934, as in effect on
         December 31, 1984.

                  (7) "SUBSIDIARY" shall mean any corporation more than 50% of
         whose outstanding stock having ordinary voting power in the election of
         directors is owned, directly or indirectly, by this corporation or by a
         Subsidiary or by this corporation and one or more Subsidiaries;
         provided, however, that for the proposes of the definition of Related
         Person set forth in Paragraph (B)(3) of this Article THIRTEENTH, the
         term


                                       15
<PAGE>   19
         "Subsidiary" shall mean only a corporation of which a majority of each
         class of equity security is owned, directly or indirectly, by this
         corporation.

                  (8) "CONTINUING DIRECTOR" shall mean any member of the Board
         of Directors of this corporation who is unaffiliated with, and not a
         nominee of, the Related Person and was a member of the Board prior to
         the time that the Related Person became a Related Person, and any
         successor of a Continuing Director who is unaffiliated with, and not a
         nominee of, the Related Person and who is recommended to succeed a
         Continuing Director by a majority of Continuing Directors then on the
         Board of Directors.

                  (9) "FAIR MARKET VALUE" shall mean: (1) in the case of stock,
         the highest closing sale price during the 30-day period preceding the
         date in question of a share of such stock on the Composite Tape of New
         York Stock Exchange-Listed stocks, or, if such stock is not quoted on
         the New York Stock Exchange-Composite Tape, on the principal United
         States securities exchange registered under the Securities Exchange Act
         of 1934 on which such stock is listed, or, if such stock is not listed
         on any such exchange, the highest closing sales price or bid quotation
         with respect to a share of such stock during the 30-day period
         preceding the date in question on the National Association of
         Securities Dealers, Inc. Automated Quotation System or any system then
         in use, or if no such quotations are available, the fair market value
         on the date in question of a share of such stock as determined by a
         majority of the Continuing Directors in good faith; and (2) in the case
         of stock of any class or series which is not traded on any United
         States registered securities exchange nor in the over-the-counter
         market or in the case of property other than cash or stock, the fair
         market value of such property on the date in question as determined by
         a majority of the Continuing Directors in good faith.

                  (10) In the event of any Business Transaction in which the
         corporation survives, the phrase "any consideration other than cash to
         be received" as used in Paragraph (A)(2)(b) and (A)(2)(c) of this
         Article THIRTEENTH shall include the shares of common stock and/or the
         share of any other class of outstanding Voting Stock retained by the
         holders of such shares.

                  (11) "ANNOUNCEMENT DATE" shall mean the date of first public
         announcement of the proposed Business Transaction.

                  (12) "DETERMINATION DATE" shall mean the date on which the
         Related Person became a Related Person.

                  (13) "CONSUMMATION DATE" shall mean the date of the
         consummation of the Business Transaction.

                  (14) The terms "VOTING STOCK" shall mean all outstanding
         shares of capital stock of all classes and series of the corporation
         entitled to vote generally in the election of directors of the
         corporation, in each case voting together as a single class.

                                       16
<PAGE>   20
         (C) If the Continuing Directors constitute at least a majority of the
Board of Directors of the corporation, a majority of such Continuing Directors
shall have the power and duty to determine, on the basis of information known to
them after reasonable inquiry, all facts necessary to determine compliance with
this Article THIRTEENTH, including, without limitation:

                  (1) Whether a person is a Related Person;

                  (2) The number of shares of Voting Stock beneficially owned by
         any person;

                  (3) Whether a person is an Affiliate or Associate of another
         person;

                  (4) Whether the requirements of (A) of this Article THIRTEENTH
         have been met with respect to any Business Transaction; and

                  (5) Whether the assets which are the subject of any Business
         Transaction have, or the consideration to be received for the issuance
         or transfer of securities by the corporation or any Subsidiary in any
         Business Transaction has, an aggregate Fair Market Value of $10,000,000
         or more. The good faith determination of a majority of the Continuing
         Directors on such matters shall be conclusive and binding for all
         purposes of this Article THIRTEENTH.

         (D) Nothing contained in this Article THIRTEENTH shall be construed to
relieve any Related Person from any fiduciary obligation imposed by law.

         (E) Notwithstanding anything contained in this certificate of
incorporation to the contrary, the affirmative vote of (1) the holders of at
least 51% of the Voting Stock, voting together as a single class, and (2) the
holders of a least 51% of the Voting Stock, voting together as a single class,
other than shares of Voting Stock beneficially owned by a Related Person, shall
be required to alter, amend or repeal this Article THIRTEENTH or to adopt any
provision inconsistent therewith.

         FOURTEENTH: Any action required or permitted to be taken by the holders
of the common stock of the corporation must be effected at a duly called annual
or special meeting of such holders and may not be effected by any consent in
writing by such holders. Except as otherwise required by law and subject to the
rights of the holders of any series of preferred stock, special meetings of
stockholders of the corporation may be called only by the Chief Executive
Officer of the corporation or by the Board of Directors pursuant to a resolution
approved by the Board of Directors.

         FIFTEENTH: Notwithstanding anything contained in this certificate of
incorporation to the contrary, the affirmative vote of the holders of at least
75 percent in voting power of all the shares of the corporation entitled to vote
generally in the election of directors, voting together as a single class, shall
be required to alter, amend or repeal Article FIFTH, Article SIXTH, Article
FOURTEENTH or this Article FIFTEENTH or to adopt any provision inconsistent
therewith.

                                       17
<PAGE>   21
I, the undersigned, _________________________________, Secretary of KERR-MCGEE
HOLDCO, INC. a Delaware corporation, do hereby certify that the foregoing is a
full, true, and correct copy of the Restated Certificate of Incorporation of
said Corporation in effect on the date of this certificate.

Given under my hand and seal of the Corporation this ______ day of
_________________, _____.



                                                 -------------------------------
                                                 Secretary

(SEAL)




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