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                               AMENDMENT NO. 15
                                      TO
                          ATLANTIC RICHFIELD COMPANY
                    1985 EXECUTIVE LONG-TERM INCENTIVE PLAN
                         _____________________________

Pursuant to the power of amendment reserved therein, the Atlantic Richfield
Company 1985 Executive Long-Term Incentive Plan (the "Plan") is hereby amended,
effective immediately, with respect to any Anticipatory Change of Control or
Change of Control related to a merger of a subsidiary of BP Amoco p.l.c. with
and into Atlantic Richfield Company, as follows:

1.   Article I, Section 2(f) of the plan is amended to read as follows:

     "(f) "Comparison Group" means:

          (i)   Chevron Corporation, Conoco Inc., Exxon Mobil Corporation,
     Occidental Petroleum Corporation, Phillips Petroleum Company, Texaco Inc.
     and Unocal Corporation; provided, however, that if any member of the
     Comparison Group ceases to exist during a Performance Period ("Terminated
     Member") the Organization and Compensation Committee of the Board of
     Directors (the "Committee") shall designate another entity as a member of
     the Comparison Group ("New Member"), which entity shall have
     characteristics as common as possible with the existing members of the
     Comparison Group, as determined in the sole discretion of the Committee;
     provided, further that the performance of the Terminated Member shall be
     used to calculate the Company Performance Ranking through the date it
     ceased to exist and the performance of the New Member shall be used to
     calculate the Company Performance Ranking for the remainder of the
     Performance Period.

          (ii)  For the 1997-1999 Performance Period, a new company will not be
     selected to replace Mobil Corporation. Instead, the actual TSR performance
     of Mobil Corporation will be used through the day the Common Stock of Mobil
     Corporation ceases trading on the NYSE. In addition, for the time period
     commencing on the date when the Common Stock of Mobil Corporation ceases
     trading on the NYSE and ending on the close of an applicable Performance
     Period, as defined in Article I, Section 2(n) of the Plan, the TSR of Mobil
     Corporation will be measured by multiplying the price of a share of Common
     Stock of Exxon Mobil Corporation by 1.32015."

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2.   Article V, Section 9(d) of the Plan is amended to read as follows:

          "(d)  The Plan may not be amended or terminated on or after a Change
     of Control until all outstanding Stock Options have been exercised or
     expired and all payments of Contingent Restricted Stock under the Plan have
     been made, except as deemed necessary by BP Amoco to make administrative
     modifications provided that any such modification does not adversely affect
     the rights or benefits of any Participant, other than a modification which
     has a de minimis effect on a Participant's rights, benefits or
     obligations."


Executed this 15th day of February, 2000.

ATTEST                                        ATLANTIC RICHFIELD COMPANY



BY:  [signed by Armineh Simonian]      BY:  [signed by John H. Kelly]
   -------------------------------        ----------------------------
                                            JOHN H. KELLY
                                            Senior Vice President
                                            Human Resources

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