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                                                                   EXHIBIT 10.11

        AMENDMENT TO THE AMENDED AND RESTATED CHANGE IN CONTROL AGREEMENT

                   This Amendment (the "Amendment") to the Amended and Restated
Change in Control Agreement dated October 26, 2000 (the "Agreement") between
OSCA, Inc., a Delaware corporation (the "Company"), together with any of its
subsidiaries or successors in interest, including a successor in a Change in
Control (as defined in the Agreement), (the "Employer"), and __________________
(the "Executive") is made as of _____________, 2001.

                   WHEREAS, the parties desire to amend the Agreement changing
the definition of "Annual Compensation" and adding a provision requiring to
Employer to pay certain legal fees incurred by the Executive pertaining to this
Agreement.

                   NOW THEREFORE, for and in good and valuable consideration,
the receipt of which is hereby acknowledged, the changes to the Change in
Control Agreement are in effect effective August 29, 2001 as follows:

         1. The current Agreement defines Annual Compensation as follows:
Section 3. Certain Definitions, (a) "Annual Compensation" currently states: (a)
"Annual Compensation" means Executive's annual base salary as in effect
immediately prior to the Change in Control, plus an amount equal to all other
amounts paid to Executive as wages, bonuses, commissions, profit sharing or
other cash compensation for services rendered during the twelve month period
immediately prior to the Change in Control.

                  By this Amendment Section 3. Certain Definitions, (a) "Annual
Compensation" is replaced by the following provision:

                  (a) "Annual Compensation" means Executive's annual base
salary, plus bonus, deferred bonus, 401(K) contributions matched by the Company,
profit sharing contributions, make whole payments regarding 401(K) and profit
sharing contributions, plus payments made under the executive car program and an
amount equal to all other amounts paid to Executive as wages, and other cash
compensation for services rendered on an annualized basis. For purposes of
calculating an Executive's Annual Compensation, the calculation shall include
the highest amount for each category stated above paid by the Company to the
Executive for the last three years.

         2. In addition, a new paragraph, Section 11 Legal Fees, is added as
follows:

                  "11. Legal Fees. If after a Change in Control, the Executive
institutes any legal action in seeking to obtain or enforce or is required to
defend in any legal action the validity or enforceability of any right or
benefit provided by this Agreement, the Company shall pay for all actual legal
fees and expenses reasonably incurred (as incurred) by such Executive,
regardless of the outcome of such action."


         In WITNESS WHEREOF, the parties hereto have executed this Amendment to
the Agreement effective as of the date first written above. All other terms and
conditions of your Agreement remain unchanged.

         OSCA, Inc.


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         Executive:


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         Agreed and accepted