Exhibit (10)(h)

               THE LUBRIZOL CORPORATION 1991 STOCK INCENTIVE PLAN
                                  (As Amended)

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, the date specified pursuant to Section 10 on which such Option
      is granted.



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.



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.



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



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



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



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 on which the Committee makes
      the annual grant to employees generally, 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 estate or by the person or persons to whom the
            Outside Director's rights under the



THE LUBRIZOL CORPORATION                                                  Page 8
1991 STOCK INCENTIVE PLAN

            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



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



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



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. The termination date of
the Plan is November 15, 2004, on which date the Plan shall expire but without
affecting any options then outstanding.