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                                                                  Exhibit (10(h)

               THE LUBRIZOL CORPORATION 1991 STOCK INCENTIVE PLAN
                         (As Amended November 10, 2003)


Section 1. Purpose.

     The purposes of The Lubrizol Corporation 1991 Stock Incentive Plan are to
encourage selected employees of The Lubrizol Corporation and its Subsidiaries
and directors of the Company to acquire a proprietary and vested interest in the
growth and performance of the Company, to generate an increased incentive to
contribute to the Company's future success and prosperity, thus enhancing the
value of the Company for the benefit of shareholders, and to enhance the ability
of the Company and its Subsidiaries to attract and retain individuals of
exceptional talent upon whom, in large measure, the sustained progress, growth
and profitability of the Company depends.

Section 2. Definitions.

     As used in the Plan, the following terms shall have the meanings set forth
below:

          (a) "Award" means any Option, Stock Appreciation Right, Restricted
     Stock Award, or Stock Award granted pursuant to the provisions of the Plan.

          (b) "Award Agreement" means a written document evidencing any Award
     granted hereunder, signed by the Company and delivered to the Participant
     or Outside Director, as the case may be.

          (c) "Board" means the Board of Directors of the Company.

          (d) "Code" means the Internal Revenue Code of 1986, as amended from
     time to time.

          (e) "Committee" means a committee of not less than three (3) Outside
     Directors of the Board, each of whom shall be a "disinterested person"
     within the meaning of Rule 16b-3(d)(3) promulgated by the Securities and
     Exchange Commission under the Securities Exchange Act of 1934, as amended
     (the "Exchange Act"), or any successor rule or statute.

          (f) "Company" means The Lubrizol Corporation.

          (g) "Employee" means any employee of the Company or of any Subsidiary.

          (h) "Fair Market Value" means the average of the high and low price of
     a Share on the New York Stock Exchange on the Grant Date (in the case of a
     Grant), or any other relevant date.

          (i) "Grant Date" means the date on which the Board approves the grant
     of an Option, Stock Appreciation Right, Restricted Stock Award, or Stock
     Award, and, with respect to an Option granted to an Outside Director
     pursuant to Section 10, the date of the Shareholders' Meeting on which such
     Option is granted.



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THE LUBRIZOL CORPORATION                                                  Page 2
1991 STOCK INCENTIVE PLAN


          (j) "Incentive Stock Option" means an Option that is intended to meet
     the requirements of Section 422A of the Code or any successor provision
     thereto.

          (k) "Non-Statutory Stock Option" means an Option that is not intended
     to be an Incentive Stock Option.

          (l) "Option" means an option to purchase Shares granted hereunder.

          (m) "Option Price" means the purchase price of each Share under an
     Option.

          (n) "Outside Director" means a member of the Board who is not an
     employee of the Company or of any Subsidiary.

          (o) "Participant" means an Employee who is selected by the Committee
     to receive an Award under the Plan.

          (p) "Plan" means The Lubrizol Corporation 1991 Stock Incentive Plan.

          (q) "Restricted Stock Award" means an award of restricted Shares under
     Section 8 hereof.

          (r) "Restriction Period" means the period of time specified in an
     Award Agreement during which the following conditions remain in effect: (i)
     certain restrictions on the sale or other disposition of Shares awarded
     under the Plan, (ii) subject to the terms of the applicable Award
     Agreement, the continued employment of the Participant, and (iii) such
     other conditions as may be set forth in the applicable Award Agreement.

          (s) "Shareholders' Meeting" means the annual meeting of shareholders
     of the Company in each year.

          (t) "Shares" means common shares without par value of the Company.

          (u) "Stock Appreciation Right" means the right to receive a payment in
     cash or in Shares, or in any combination thereof, from the Company equal to
     the excess of the Fair Market Value of a stated number of Shares at the
     exercise date over a fixed price for such Shares.

          (v) "Stock Award" means the grant of unrestricted Shares under the
     Plan.

          (w) "Subsidiary" means a corporation which is at least 80% owned,
     directly or indirectly, by the Company.

          (x) "Voting Stock" means the then-outstanding securities entitled to
     vote generally in the election of directors of the Company.



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THE LUBRIZOL CORPORATION                                                  Page 3
1991 STOCK INCENTIVE PLAN


Section 3. Administration.

     The Plan shall be administered by the Committee. Members of the Committee
shall be appointed by and serve at the pleasure of the Board, and may resign by
written notice filed with the Chairman of the Board or the Secretary of the
Company. A vacancy on the Committee shall be filled by the appointment of a
successor member by the Board. Subject to the express provisions of this Plan,
the Committee shall have conclusive authority to select Employees to be
Participants for Awards and determine the type and number of Awards to be
granted, to construe and interpret the Plan, any Award granted hereunder, and
any Award Agreement entered into hereunder, and to establish, amend, and rescind
rules and regulations for the administration of this Plan and shall have such
additional authority as the Board may from time to time determine to be
necessary or desirable. Notwithstanding the foregoing, the Committee shall not
have discretion with respect to Options granted to Outside Directors pursuant to
Section 10 such as to prevent any Award granted under this Plan from meeting the
requirements for exemption from Section 16(b) of the Exchange Act, as set forth
in Rule 16b-3 thereunder or any successor rule or statute.

Section 4. Shares Subject to the Plan.

          (a) Subject to adjustment as provided in the Plan, the total number of
     Shares available under the Plan in each calendar year shall be one percent
     (1%) of the total outstanding Shares as of the first day of any year for
     which the Plan is in effect; provided that such number shall be increased
     in any year by the number of Shares available for grant hereunder in
     previous years but not covered by Awards granted hereunder in such previous
     years; provided further, that a total of no more than two million
     (2,000,000) Shares shall be available for the grant of Incentive Stock
     Options under the Plan; and provided further, that no more than four
     hundred thousand (400,000) Shares shall be available for grant to any
     Participant during a calendar year. Settlement of an Award, whether by the
     issuance of Shares or the payment of cash, shall not be deemed to be the
     grant of an Award hereunder. In addition, any Shares issued by the Company
     through the assumption or substitution of outstanding grants from an
     acquired company shall not reduce the Shares available for grants under the
     Plan. Any Shares issued hereunder may consist, in whole or in part, of
     authorized and unissued Shares or treasury shares. If any Shares subject to
     any Award granted hereunder are forfeited or if such Award otherwise
     terminates without the issuance of such Shares or payment of other
     consideration in lieu of such Shares, the Shares subject to such Award, to
     the extent of any such forfeiture or termination, shall again be available
     for grant under the Plan as if such Shares had not been subject to an
     Award.

          (b) The number of Shares which remain available for grant pursuant to
     this Plan, together with Shares subject to outstanding Awards, at the time
     of any change in the Company's capitalization, including stock splits,
     stock dividends, mergers, reorganizations, consolidations,
     recapitalizations, or other changes in corporate structure, shall be
     appropriately and proportionately adjusted to reflect such change in
     capitalization.

Section 5. Eligibility.

     Any Employee shall be eligible to be selected as a Participant.


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THE LUBRIZOL CORPORATION                                                  Page 4
1991 STOCK INCENTIVE PLAN


Section 6. Stock Options.

     Non-Statutory Stock Options and Incentive Stock Options may be granted
hereunder to Participants either separately or in conjunction with other Awards
granted under the Plan. Any Option granted to a Participant under the Plan shall
be evidenced by an Award Agreement in such form as the Committee may from time
to time approve. Any such Option shall be subject to the following terms and
conditions and to such additional terms and conditions, not inconsistent with
the provisions of the Plan, as the Committee shall deem desirable.

          (a) Option Price. The purchase price per Share under an Option shall
     be fixed by the Committee in its sole discretion; provided that the
     purchase price shall not be less than one hundred percent (100%) of the
     Fair Market Value of the Share on the Grant Date of the Option. Payment of
     the Option Price may be made in cash, Shares, or a combination of cash and
     Shares, as provided in the Award Agreement relating thereto.

          (b) Option Period. The term of each Option shall be fixed by the
     Committee in its sole discretion; provided that no Incentive Stock Option
     shall be exercisable after the expiration of ten years from the Grant Date;
     and provided further, that no reload Option granted to a Participant
     pursuant to the terms of Section 6(e) shall be exercisable after the
     expiration of the term of the Option that gave rise to the grant of such
     reload Option.

          (c) Exercise of Option. Options shall be exercisable to the extent of
     fifty percent (50%) of the Shares subject thereto after one year from the
     Grant Date, seventy-five percent (75%) of such Shares after two years from
     the Grant Date, and one hundred percent (100%) of such Shares after three
     years from the Grant Date, subject to any provisions respecting the
     exercisability of Options that may be contained in an Award Agreement;
     provided that a reload Option granted to a Participant pursuant to the
     terms of Section 6(e) shall be exercisable to the extent of one hundred
     percent (100%) of such Shares from the Grant Date.

          (d) Incentive Stock Options. The aggregate Fair Market Value of the
     Shares with respect to which Incentive Stock Options held by any
     Participant which are exercisable for the first time by such Participant
     during any calendar year under the Plan (and under any other benefit plans
     of the Company, of any parent corporation, or Subsidiary) shall not exceed
     $100,000 or, if different, the maximum limitation in effect at the Grant
     Date under Section 422A of the Code, or any successor provision, and any
     regulations promulgated thereunder. The terms of any Incentive Stock Option
     granted hereunder shall comply in all respects with the provisions of
     Section 422A of the Code, or any successor provision, and any regulations
     promulgated thereunder.

          (e) Reload. In the event that a Participant or an Outside Director
     exercises an Option other than a reload Option granted pursuant to this
     Section 6(e), and pays some or all of the Option Price with Shares, the
     Committee in its discretion may grant to such Participant or Outside
     Director a reload Option to purchase the number of Shares equal to the
     number of Shares used as payment of the Option Price, subject to the
     limitations described below. Options granted to Participants pursuant to
     this Section 6(e) shall have terms and conditions as described in this
     Section 6 and Options granted to Outside Directors pursuant to this Section
     6(e) shall have terms and conditions as described in

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THE LUBRIZOL CORPORATION                                                  Page 5
1991 STOCK INCENTIVE PLAN


     Section 10. Options granted pursuant to this Section 6(e) shall be of the
     same character (i.e., Non-Statutory Stock Options or Incentive Stock
     Options) as the Option that is exercised to give rise to the grant of the
     reload Option, provided that if an Incentive Stock Option cannot be granted
     under this Section 6(e) in compliance with Section 422A of the Code, then a
     Non-Statutory Stock Option shall be granted in lieu thereof. Options may be
     granted pursuant to this Section 6(e) only to the extent that the number of
     Shares covered by such Option grants does not, when added to the number of
     Shares covered by Awards previously granted during such calendar year,
     exceed the limitation set forth in Section 4(a).

     Shares received upon the exercise of an Option granted pursuant to this
     Section 6(e) may not be sold or otherwise transferred (i) by a Participant
     until such Participant has met the Share ownership guideline for such
     Participant, if any, set by the Company, and then only to the extent that
     the Participant continues to meet such ownership guideline immediately
     after such sale, or (ii) by an Outside Director until such Outside Director
     ceases to be an Outside Director, provided, however, that a Participant or
     Outside Director may use such Shares as payment of the Option Price of
     Options granted under this Plan to the extent permitted by the applicable
     Award Agreement, in which case a number of the Shares (equal to the number
     of Shares used for such payment) purchased by the exercise of such Options
     also shall be subject to the same restrictions upon transferability.
     Certificates for such Shares with a transferability restriction shall bear
     a legend referencing such restriction.

     Notwithstanding the foregoing, effective for grants of Options on or after
     November 11, 2002, this Section 6(e) is deleted.

Section 7. Stock Appreciation Rights.

     Stock Appreciation Rights may be granted hereunder to Participants either
separately or in conjunction with other Awards granted under the Plan and may,
but need not, relate to a specific Option granted under Section 6. The
provisions of Stock Appreciation Rights need not be the same with respect to
each Participant. Any Stock Appreciation Right related to a Non-Statutory Stock
Option may be granted at the same time such Option is granted or at any time
thereafter before exercise or expiration of such Option. Any Stock Appreciation
Right related to an Incentive Stock Option must be granted at the same time such
Option is granted. Any Stock Appreciation Right related to an Option shall be
exercisable only to the extent the related Option is exercisable. In the case of
any Stock Appreciation Right related to any Option, the Stock Appreciation Right
or applicable portion thereof shall terminate and no longer be exercisable upon
the termination or exercise of the related Option. Similarly, upon exercise of a
Stock Appreciation Right as to some or all of the Shares covered by a related
Option, the related Option shall be canceled automatically to the extent of the
Stock Appreciation Rights exercised, and such Shares shall not thereafter be
eligible for grant under Section 4(a). The Committee may impose such conditions
or restrictions on the exercise of any Stock Appreciation Right as it shall deem
appropriate.

Section 8. Restricted Stock Awards.

          (a) Issuance. Restricted Stock Awards may be issued hereunder to
     Participants, either separately or in conjunction with other Awards granted
     under the Plan. Each Award


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THE LUBRIZOL CORPORATION                                                  Page 6
1991 STOCK INCENTIVE PLAN


     under this Section 8 shall be evidenced by an Award Agreement between the
     Participant and the Company which shall specify the vesting schedule, any
     rights of acceleration and such other terms and conditions as the Board
     shall determine, which need not be the same with respect to each
     Participant.

          (b) Registration. Shares issued under this Section 8 shall be
     evidenced by issuance of a stock certificate or certificates registered in
     the name of the Participant bearing the following legend and any other
     legend required by, or deemed appropriate under, any federal or state
     securities laws:

          The sale or other transfer of the common shares represented by this
          certificate is subject to certain restrictions set forth in the Award
          Agreement between ___________________ (the registered owner) and The
          Lubrizol Corporation dated _______________, under The Lubrizol
          Corporation 1991 Stock Incentive Plan. A copy of the Plan and Award
          Agreement may be obtained from the Secretary of The Lubrizol
          Corporation.

     Unless otherwise provided in the Award Agreement between the Participant
     and the Company, such certificates shall be retained by the Company until
     the expiration of the Restriction Period. Upon the expiration of the
     Restriction Period, the Company shall (i) cause the removal of the legend
     from the certificates for such Shares as to which a Participant is entitled
     in accordance with the Award Agreement between the Participant and the
     Company and (ii) release such Shares to the custody of the Participant.

          (c) Forfeiture. Except as otherwise determined by the Committee at the
     Grant Date, upon termination of employment of the Participant for any
     reason during the Restriction Period, all Shares still subject to
     restriction shall be forfeited by the Participant and retained by the
     Company; provided that in the event of a Participant's retirement,
     permanent disability, death, or in cases of special circumstances, the
     Committee may, in its sole discretion, when it finds that a waiver would be
     in the best interests of the Company, waive in whole or in part any or all
     remaining restrictions with respect to such Participant's Shares. In such
     case, unrestricted Shares shall be issued to the Participant at such time
     as the Committee determines.

          (d) Rights as Shareholders. At all times during the Restriction
     Period, Participants shall be entitled to full voting rights with respect
     to all Shares awarded under this Section 8 and shall be entitled to
     dividends with respect to such Shares.

Section 9. Stock Awards.

     Awards of Shares may be granted hereunder to Participants, either
separately or in conjunction with other Awards granted under the Plan. Subject
to the provisions of the Plan, the Committee shall have sole and complete
authority to determine (i) the Employees to whom such Awards shall be granted,
(ii) the time or times at which such Awards shall be granted, (iii) the number
of Shares to be granted pursuant to such Awards, and (iv) all other conditions
of the Awards. Such conditions may include issuance of Shares at the time of the
Award is granted or issuance of Shares at a time or times subsequent to the time
the Award is granted, which subsequent times may be specifically established by
the Committee and/or may be determined by



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THE LUBRIZOL CORPORATION                                                  Page 7
1991 STOCK INCENTIVE PLAN


reference to the satisfaction of one or more performance measures specified by
the Committee. The provisions of stock awards need not be the same with respect
to each Participant.

Section 10. Outside Directors' Options.

          On the close of business on the date of each Shareholders' Meeting,
     each Outside Director shall automatically be granted an Option to purchase
     2,500 Shares. In addition, on April 23, 2001, each Outside Director shall
     automatically be granted an Option to purchase 2,500 Shares. All Options
     granted under this Section 10 shall be Non-Statutory Stock Options and
     shall be subject to the following terms and conditions and to such
     additional terms and conditions, not inconsistent with the provisions of
     the Plan, as are contained in the applicable Award Agreement.

          (a) Option Price. The purchase price per Share shall be one hundred
     percent (100%) of the Fair Market Value of the Share on the Grant Date.
     Payment of the Option Price may be made in cash, Shares, or a combination
     of cash and Shares, as provided in the Award Agreement in effect from time
     to time.

          (b) Option Period. The term during which Options granted under this
     Section 10 shall be exercisable shall be ten (10) years from the Grant
     Date; provided that no reload Option granted to an Outside Director
     pursuant to the terms of Section 6(e) shall be exercisable after the
     expiration of the term of the Option that gave rise to the grant of such
     reload Option.

          (c) Exercise of Options. Subject to the provisions of this Section
     10(c), Options shall be exercisable to the extent of fifty percent (50%) of
     the Shares subject thereto after one year from the Grant Date, seventy-five
     percent (75%) of such Shares after two years from the Grant Date, and one
     hundred percent (100%) of such Shares after three years from the Grant
     Date; provided that a reload Option granted to an Outside Director pursuant
     to the terms of Section 6(e) shall be exercisable to the extent of one
     hundred percent (100%) of such Shares from the Grant Date. Options may be
     exercised by an Outside Director during the period that the Outside
     Director remains a member of the Board and under the circumstances
     described below.

               (i) If an Outside Director retires under a retirement plan or
          policy of the Company, then Options held by such Outside Director may
          be exercised for a period of thirty-six (36) months following
          retirement, to the extent of 100% of the Shares covered by such
          Options (notwithstanding the extent to which the Outside Director
          otherwise would have been entitled to exercise such Options at the
          date of retirement), provided that in no event shall an Option be
          exercisable after the expiration of the Option period provided in
          Section 10(b).

               (ii) In the event of the death of an Outside Director while
          serving as a director, Options held by such Outside Director may be
          exercised for a period of twelve (12) months following the date of
          death, (A) to the extent of 100% of the Shares covered by such Options
          (notwithstanding the extent to which the Outside Director otherwise
          would have been entitled to exercise the Option at the date of death),
          and (B) only by the executor or administrator of the Outside
          Director's


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THE LUBRIZOL CORPORATION                                                  Page 8
1991 STOCK INCENTIVE PLAN


          estate or by the person or persons to whom the Outside Director's
          rights under the Options shall pass by the Outside Director's will or
          the laws of descent and distribution, provided that in no event shall
          an Option be exercisable after the expiration of the Option period
          provided in Section 10(b).

               (iii) If an Outside Director shall cease to be a director for any
          reason other than retirement under a retirement plan or policy of the
          Company or death, Options held by such Outside Director may be
          exercised for a period of three (3) months following such cessation,
          to the extent of 100% of the Shares covered by such Options
          (notwithstanding the extent to which the Outside Director otherwise
          would have been entitled to exercise such Options at the date of such
          cessation), provided that in no event shall an Option be exercisable
          after the expiration of the Option period provided in Section 10(b).

               (iv) In the event an Outside Director, after ceasing to be a
          director, dies during and subject to one of the periods described in
          Section 10(c)(i) or (iii), while possessed of unexercised Options, the
          executor or administrator of the Outside Director's estate, or the
          person entitled by will or the applicable laws of descent and
          distribution, may exercise such Options held by the Outside Director
          at the time of the Outside Director's death during the period that is
          applicable, as follows:

                    (A) If Section 10(c)(i) was in effect, for one year after
               the Outside Director's death;

                    (B) If Section 10(c)(iii) was in effect, for three months
               after the Outside Director's death;

          provided that, in no event shall the Option be exercisable after the
          expiration of the Option period provided in Section 10(b).

Section 11. Change in Control.

     Notwithstanding the provisions of Sections 6(c) and 10(c), Options shall
become exercisable with respect to 100% of the Shares upon the occurrence of any
Change in Control (as hereafter defined) of the Company; except that no Options
shall be exercised prior to the end of six months from the Grant Date.

     Notwithstanding the provisions of Section 8 and the applicable Award
Agreement, any restricted Shares shall be 100% vested and without any
restrictions upon the occurrence of any Change in Control of the Company.

     For all purposes of the Plan, a "Change in Control" shall have occurred if
any of the following events shall occur:

          (a) The Company is merged, consolidated or reorganized into or with
     another corporation or other legal person, and immediately after such
     merger, consolidation or reorganization less than a majority of the
     combined voting power of the then-outstanding securities of such
     corporation or person immediately after such transaction are held in the


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THE LUBRIZOL CORPORATION                                                  Page 9
1991 STOCK INCENTIVE PLAN

     aggregate by the holders of Voting Stock of the Company immediately prior
     to such transaction;

          (b) The Company sells all or substantially all of its assets to any
     other corporation or other legal person, and less than a majority of the
     combined voting power of the then-outstanding securities of such
     corporation or person immediately after such sale are held in the aggregate
     by the holders of Voting Stock of the Company immediately prior to such
     sale;

          (c) There is a report filed on Schedule 13D or Schedule 14D-l (or any
     successor schedule, form or report), each as promulgated pursuant to the
     Exchange Act, disclosing that any person (as the term "person" is used in
     Section 13(d)(3) or Section 14(d)(2) of the Exchange Act) has become the
     beneficial owner (as the term "beneficial owner" is defined under Rule
     13(d)(3) or any successor rule or regulation promulgated under the Exchange
     Act) of securities representing 20% or more of the Voting Stock;

          (d) The Company files a report or proxy statement with the Securities
     and Exchange Commission pursuant to the Exchange Act disclosing in response
     to Form 8-K or Schedule 14A (or any successor schedule, form or report or
     item therein) that a change in control of the Company has or may have
     occurred or will or may occur in the future pursuant to any then-existing
     contract or transaction; or

          (e) If during any period of two consecutive years, individuals who at
     the beginning of any such period constitute the Directors of the Company
     cease for any reason to constitute at least a majority thereof, provided,
     however, that for purposes of this Section 11(e), each Director who is
     first elected, or first nominated for election by the Company's
     stockholders, by a vote of at least two thirds of the Directors of the
     Company (or a committee thereof) then still in office who were Directors of
     the Company at the beginning of any such period will be deemed to have been
     a Director of the Company at the beginning of such period.

     Notwithstanding the foregoing provisions of Section 11(c) or 11(d) hereof,
unless otherwise determined in a specific case by majority vote of the Board, a
"Change in Control" shall not be deemed to have occurred for purposes of the
Plan solely because (i) the Company, (ii) an entity in which the Company
directly or indirectly beneficially owns 50% or more of the voting securities,
or (iii) any employee stock ownership plan or any other employee benefit plan
sponsored by the Company, either files or becomes obligated to file a report or
a proxy statement under or in response to Schedule 13D, Schedule 14D-l, Form 8-K
or Schedule 14A (or any successor schedule, form or report or item therein)
under the Exchange Act, disclosing beneficial ownership by it of shares of
Voting Stock, whether in excess of 20% or otherwise, or because the Company
reports that a change in control of the Company has or may have occurred or will
or may occur in the future by reason of such beneficial ownership.

Section 12. Amendments and Termination.

     The Board may, at any time, amend, alter or terminate the Plan, but no
amendment, alteration, or termination shall be made that would impair the rights
of an Outside Director or


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THE LUBRIZOL CORPORATION                                                 Page 10
1991 STOCK INCENTIVE PLAN


Participant under an Award theretofore granted, without the Outside Director's
or Participant's consent, or that without the approval of the shareholders
would:

          (a) except as is provided in Sections 4(b) and 13(c) of the Plan,
     increase the total number of Shares which may be issued under the Plan;

          (b) change the class of employees eligible to participate in the Plan;
     or

          (c) materially increase the benefits accruing to Participants under
     the Plan;

so long as such approval is required by law or regulation; provided that, as
long as required by law or regulation, the provisions of Section 10 hereof may
not be amended or altered more than once every six (6) months, other than to
comport with changes in the Code, the Employee Retirement Income Security Act,
or the rules thereunder.

     The Committee may amend the terms of any Award heretofore granted (except,
with respect to Options granted pursuant to Section 10 hereof, only to the
extent not inconsistent with Rule 16b-3 under the Exchange Act or any successor
rule or statute), prospectively or retroactively, but no such amendment shall
impair the rights of any Participant or Outside Director without his consent.

Section 13. General Provisions.

          (a) No Option, Stock Appreciation Right, or Restricted Stock Award
     shall be assignable or transferable by a Participant or an Outside Director
     otherwise than by will or the laws of descent and distribution, and Options
     and Stock Appreciation Rights may be exercised during the Participant's or
     Outside Director's lifetime only by the Participant or the Outside Director
     or, if permissible under applicable law, by the guardian or legal
     representative of the Participant or Outside Director.

          (b) The term of each Award shall be for such period of months or years
     from its Grant Date as may be determined by the Committee or as set forth
     in the Plan; provided that in no event shall the term of any Incentive
     Stock Option or any Stock Appreciation Right related to any Incentive Stock
     Option exceed a period of ten (10) years from the Grant Date.

          (c) In the event of a merger, reorganization, consolidation,
     recapitalization, stock dividend or other change in corporate structure
     such that Shares are changed into or become exchangeable for a larger or
     smaller number of Shares, thereafter the number of Shares subject to
     outstanding Awards granted to Participants and to any Shares subject to
     Awards to be granted to Participants pursuant to this Plan shall be
     increased or decreased, as the case may be, in direct proportion to the
     increase or decrease in the number of Shares by reason of such change in
     corporate structure; provided, however, that the number of Shares shall
     always be a whole number, and the purchase price per Share of any
     outstanding Options shall, in the case of an increase in the number of
     Shares, be proportionately reduced, and, in the case of a decrease in the
     number of Shares, shall be proportionately increased. The above adjustment
     shall also apply to any



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THE LUBRIZOL CORPORATION                                                 Page 11
1991 STOCK INCENTIVE PLAN


     Shares subject to Options granted to Outside Directors pursuant to the
     provisions of Section 10.

          (d) No Employee shall have any claim to be granted any Award under the
     Plan and there is no obligation for uniformity of treatment of Employees or
     Participants under the Plan.

          (e) The prospective recipient of any Award under the Plan shall not,
     with respect to such Award, be deemed to have become a Participant, or to
     have any rights with respect to such Award, until and unless such recipient
     shall have executed an Award Agreement, and otherwise complied with the
     then applicable terms and conditions.

          (f) All certificates for Shares delivered under the Plan pursuant to
     any Award shall be subject to such stock-transfer orders and other
     restrictions as the Committee may deem advisable under the rules,
     regulations, and other requirements of the Securities and Exchange
     Commission, any stock exchange upon which the Shares are then listed, and
     any applicable federal or state securities law, and the Committee may cause
     a legend or legends to be put on any such certificates to make appropriate
     reference to such restrictions.

          (g) Except as otherwise required in any applicable Award Agreement or
     by the terms of the Plan, Participants shall not be required, under the
     Plan, to make any payment other than the rendering of services.

          (h) The Company shall be authorized to withhold from any payment under
     the Plan, whether such payment is in Shares or cash, all withholding taxes
     due in respect of such payment hereunder and to take such other action as
     may be necessary in the opinion of the Company to satisfy all obligations
     for the payment of such taxes.

          (i) Nothing contained in this Plan shall prevent the Board from
     adopting other or additional compensation arrangements, subject to
     shareholder approval if such approval is required; and such arrangements
     may be either generally applicable or applicable only in specific cases.

          (j) Nothing in the Plan shall interfere with or limit in any way the
     right of the Company or any Subsidiary to terminate any Participant's
     employment at any time, nor shall the Plan confer upon any Participant any
     right to continued employment with the Company or any Subsidiary.

Section 14. Effective Date and Term of Plan.

     The Plan shall be effective as of April 22, 1991. Options may be granted
after the effective date any time prior to April 22, 2006, on which date the
Plan shall expire but without affecting any options then outstanding.