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                                                                 Exhibit (10)(o)

                              EMPLOYMENT AGREEMENT

         This EMPLOYMENT AGREEMENT (this "Agreement"), dated as of January 1,
2003, by and between The Lubrizol Corporation, an Ohio corporation (the
"Company"), and Charles P. Cooley (the "Executive");

                                   WITNESSETH:

         WHEREAS, the Executive is a senior executive of the Company and has
made and is expected to continue to make major contributions to the
profitability, growth and financial strength of the Company;

         WHEREAS, the Company desires to encourage Executive to remain with the
Company for a number of years.

         WHEREAS, this Agreement is not intended to alter materially the
compensation and benefits which the Executive could reasonably expect to receive
from the Company that are not addressed within this Agreement; and

         WHEREAS, the Executive is willing to render services to the Company on
the terms and subject to the conditions set forth in this Agreement;

         NOW, THEREFORE, the Company and the Executive agree as follows:

1. If the Executive remains in the employ of the Company until January 1, 2008,
he will receive 15,000 Lubrizol Common Shares

2. Executive will not have voting or dividend rights in number of shares listed
in 1. above, unless and until the Shares are issued.

3. The number of Shares listed in 1. above will be issued before January 1, 2008
if the Employee is employed by the Company upon the occurrence of any of the
following events:

         A.       At the discretion of the Organization and Compensation
                  Committee of the Board of Directors, upon the death of the
                  Executive.

         B.       If there is a Change of Control of the Company and Executive's
                  employment terminates prior to the earlier of January 1, 2008
                  or the third anniversary of the Change of Control, by the
                  Company for other than Good Cause or by the Executive for Good
                  Reason, or if there is a Change of Control and the Executive
                  terminates his employment for any reason during the 90 day
                  period commencing on the first anniversary of the Change in
                  Control.

                  i.       For purposes of this Agreement, there will be a
                           "Change in Control" if any of the following events
                           occurs:

                           (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 aggregate
                                    by the holders of Voting Stock

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                                    (as that term is hereafter defined) 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, 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-1 (or any successor schedule,
                                    form or report), each as promulgated
                                    pursuant to the Securities Exchange Act of
                                    1934, as amended (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
                                    13d-3 or any successor rule or regulation
                                    promulgated under the Exchange Act) of
                                    securities representing 20% or more of the
                                    combined voting power of the
                                    then-outstanding securities entitled to vote
                                    generally in the election of directors of
                                    the Company ("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
                                    clause (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
                           3(B)(i)(c) or 3(B)(i)(d) hereof, unless otherwise
                           determined in a specific case by majority vote of the
                           Board of Directors of the Company (the "Board"), a
                           "Change in Control" shall not be deemed to have
                           occurred for purposes of this Agreement solely
                           because (I) the Company, (II) an entity in which the
                           Company directly or indirectly beneficially owns 50%
                           or more of the voting securities (a


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                           "Subsidiary"), or (III) any Company-sponsored
                           employee stock ownership plan or any other employee
                           benefit plan of the Company, either files or becomes
                           obligated to file a report or a proxy statement under
                           or in response to Schedule 13D, Schedule 14D-1, 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.

                  ii.      Good Cause means the Executive committed:

                           (a)      an intentional act of fraud, embezzlement or
                                    theft in connection with his duties or in
                                    the course of his employment with the
                                    Company and/or any of its subsidiaries;

                           (b)      intentional wrongful damage to property of
                                    the Company and/or any of its subsidiaries;

                           (c)      intentional wrongful disclosure of secret
                                    processes or confidential information of the
                                    Company and/or any Subsidiary; or

                           (d)      intentional wrongful engagement in any
                                    Competitive Activity;

                           and any such act was harmful to the Company. For
                           purposes of this Agreement, no act, or failure to
                           act, on the part of the Executive will be deemed
                           "intentional" if it was due primarily to an error in
                           judgment or negligence, but will be deemed
                           "intentional" only if done, or omitted to be done, by
                           the Executive not in good faith and without
                           reasonable belief that his action or omission was in
                           the best interest of the Company. Notwithstanding the
                           foregoing, the Executive will not be deemed to have
                           been terminated for "Good Cause" hereunder unless and
                           until there is delivered to the Executive a copy of a
                           resolution duly adopted by the affirmative vote of
                           not less than three-quarters of the Board then in
                           office at a meeting of the Board called and held for
                           such purpose (after reasonable notice to the
                           Executive and an opportunity for the Executive,
                           together with his counsel, to be heard before the
                           Board), finding that, in the good faith opinion of
                           the Board, the Executive had committed an act set
                           forth above in Section 3(B)(ii) and specifying the
                           particulars thereof in detail. Nothing herein limits
                           the right of the Executive or his beneficiaries to
                           contest the validity or propriety of any such
                           determination.

                  iii.     Good Reason means within three years after the Change
                           in Control upon the occurrence of any of the
                           following events:

                           (a)      Failure to elect or reelect or otherwise to
                                    maintain the Executive in the office or the
                                    position, or a substantially equivalent
                                    office or position, of or with the Company
                                    and/or a Subsidiary, as the case may be,
                                    which the


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                                    Executive held immediately prior to a Change
                                    in Control, or the removal of the Executive
                                    as a Director of the Company (or any
                                    successor thereto) if the Executive was a
                                    Director of the Company immediately prior to
                                    the Change in Control;

                           (b)      A significant adverse change in the nature
                                    or scope of the authorities, powers,
                                    functions, responsibilities or duties
                                    attached to the position with the Company
                                    and any Subsidiary which the Executive held
                                    immediately prior to the Change in Control,
                                    a reduction in the aggregate of the
                                    Executive's Base Pay and Incentive Pay
                                    received from the Company and any
                                    Subsidiary, or the termination or denial of
                                    the Executive's rights to Employee Benefits
                                    as herein provided, any of which is not
                                    remedied within 10 calendar days after
                                    receipt by the Company of written notice
                                    from the Executive of such change, reduction
                                    or termination, as the case may be;

                           (c)      A determination by the Executive made in
                                    good faith that as a result of a Change in
                                    Control and a change in circumstances
                                    thereafter significantly affecting his
                                    position, including without limitation a
                                    change in the scope of the business or other
                                    activities for which he was responsible
                                    immediately prior to a Change in Control, he
                                    has been rendered substantially unable to
                                    carry out, has been substantially hindered
                                    in the performance of, or has suffered a
                                    substantial reduction in, any of the
                                    authorities, powers, functions,
                                    responsibilities or duties attached to the
                                    position held by the Executive immediately
                                    prior to the Change in Control, which
                                    situation is not remedied within 10 calendar
                                    days after written notice to the Company
                                    from the Executive of such determination;

                           (d)      The liquidation, dissolution, merger,
                                    consolidation or reorganization of the
                                    Company or transfer of all or a significant
                                    portion of its business and/or assets,
                                    unless the successor or successors (by
                                    liquidation, merger, consolidation,
                                    reorganization or otherwise) to which all or
                                    a significant portion of its business and/or
                                    assets have been transferred (directly or by
                                    operation of law) shall have assumed all
                                    duties and obligations of the Company under
                                    this Agreement pursuant to Section 4 hereof;

                           (e)      The Company relocates its principal
                                    executive offices, or requires the Executive
                                    to have his principal location of work
                                    changed, to any location which is over 25
                                    miles from the location thereof immediately
                                    prior to the Change of Control or to travel
                                    away from his office in the course of
                                    discharging his responsibilities or duties
                                    hereunder significantly more (in terms of
                                    either consecutive days or aggregate days in
                                    any calendar year) than was required of him
                                    prior to the Change of Control without, in
                                    either case, his prior written consent; or



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                           (f)      Without limiting the generality or effect of
                                    the foregoing, any material breach of this
                                    Agreement by the Company or any successor
                                    thereto.

4.       Successors and Assigns to the Company

         A.       The Company will require any successor (whether direct or
                  indirect, by purchase, merger, consolidation, reorganization
                  or otherwise) to all or substantially all of the business
                  and/or assets of the Company, by agreement in form and
                  substance satisfactory to the Executive, expressly to assume
                  and agree to perform this Agreement in the same manner and to
                  the same extent the Company would be required to perform if no
                  such succession had taken place. This Agreement will be
                  binding upon and inure to the benefit of the Company and any
                  successor to the Company, including without limitation any
                  persons acquiring directly or indirectly all or substantially
                  all of the business and/or assets of the Company whether by
                  purchase, merger, consolidation, reorganization or otherwise
                  (and such successor will thereafter be deemed the "Company"
                  for the purposes of this Agreement), but will not otherwise be
                  assignable, transferable or delegable by the Company.

         B.       This Agreement inures to the benefit of and is enforceable by
                  the Executive's personal or legal representatives, executors,
                  administrators, successors, heirs, distributees and/or
                  legatees.

         C.       This Agreement is personal in nature and neither of the
                  parties hereto will, without the consent of the other, assign,
                  transfer or delegate this Agreement or any rights or
                  obligations hereunder except as expressly provided in Sections
                  4(A) and (B) above. Without limiting the generality of the
                  foregoing, the Executive's right to receive the benefits
                  hereunder is not assignable, transferable or delegable,
                  whether by pledge, creation of a security interest or
                  otherwise, other than by a transfer by his will or by the laws
                  of descent and distribution and, in the event of any attempted
                  assignment or transfer contrary to this Section 4(C), the
                  Company has no liability to pay any amount so attempted to be
                  assigned, transferred or delegated.

         D.       The Company and the Executive recognize that each party will
                  have no adequate remedy at law for breach by the other of any
                  of the agreements contained herein and, in the event of any
                  such breach, the Company and the Executive hereby agree and
                  consent that the other shall be entitled to a decree of
                  specific performance, mandamus or other appropriate remedy to
                  enforce performance of this Agreement.

5. For all purposes of this Agreement, all communications including without
limitation notices, consents, requests or approvals, provided for herein must be
in writing and will be deemed to have been duly given when delivered or five
business days after having been mailed by United States registered or certified
mail, return receipt requested, postage prepaid, addressed to the Company (to
the attention of the Secretary of the Company) at its principal executive office
and to the Executive at his principal residence, or to such other address as any
party may have furnished to the other in writing and in accordance herewith,
except that notices of change of address shall be effective only upon receipt.



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6. The validity, interpretation, construction and performance of this Agreement
is governed by the laws of the State of Ohio, without giving effect to the
principles of conflict of laws of such State.

7. If any provision of this Agreement or the application of any provision hereof
to any person or circumstances is held invalid, unenforceable or otherwise
illegal, the remainder of this Agreement and the application of such provision
to any other person or circumstances shall not be affected, and the provision so
held to be invalid, unenforceable or otherwise illegal shall be reformed to the
extent (and only to the extent) necessary to make it enforceable, valid and
legal.

8. No provision of this Agreement may be modified, waived or discharged unless
such waiver, modification or discharge is agreed to in writing signed by the
Executive and the Company. No waiver by either party hereto at any time of any
breach by the other party hereto or compliance with any condition or provision
of this Agreement to be performed by such other party shall be deemed a waiver
of similar or dissimilar provisions or conditions at the same or at any prior or
subsequent time. No agreements or representations, oral or otherwise, expressed
or implied with respect to the subject matter hereof have been made by either
party which are not set forth expressly in this Agreement, other than the
Employment Agreement between Executive and the Company dated July 24, 2000,
which remains in full force and effect.

9. This Agreement may be executed in one or more counterparts, each of which
shall be deemed to be an original but all of which together will constitute one
and the same agreement.

         IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
executed and delivered as of the date first above written.

EXECUTIVE                               THE LUBRIZOL CORPORATION


                                        By:
-----------------------------              ----------------------------------
                                                Chief Executive Officer

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