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                                                                     EXHIBIT 2.7

                       AMENDMENT NO. 6 TO THE AMENDED AND
                  RESTATED OPERATIONS AND SETTLEMENT AGREEMENT

                  This Amendment No. 6 ("Amendment") to the Amended and
Restated Operations and Settlement Agreement (the "Agreement") is entered into
as of December 10, 1999, among the Commissioner of the Department of
Corporations of the State of California (the "Commissioner" acting for himself
and the Department of Corporations of the State of California (collectively,
the "State")), J. Mark Abernathy, as Special Monitor-Examiner, Caremark Rx,
Inc., f/k/a/ MedPartners, Inc., a Delaware corporation, and its successors and
assigns ("MedPartners") and MedPartners Provider Network, Inc., a California
corporation ("MPN"), as a debtor and debtor in possession in the Bankruptcy
Case. Capitalized terms not otherwise defined herein shall have the meanings
ascribed to them in the Agreement.

                                    RECITALS

                  WHEREAS, the parties entered into the Agreement as of June
16, 1999;

                  WHEREAS, the parties entered into Amendment No. 1 to the
Agreement as of July 31, 1999;

                  WHEREAS, the parties entered into Amendment No. 2 to the
Agreement as of August 31, 1999;

                  WHEREAS, the parties entered into Amendment No. 3 to the
Agreement as of September 30, 1999;

                  WHEREAS, the parties entered into Amendment No. 4 to the
Agreement as of October 31, 1999;

                  WHEREAS, the parties entered into Amendment No. 5 to the
Agreement as of November 30, 1999; and

                  WHEREAS, the parties desire to clarify and amend certain
provisions of the Agreement as set forth herein.

                  NOW THEREFORE, in consideration of the mutual covenant and
agreements contained herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties agree as
follows:

                                   AGREEMENT

                  1.       The preamble in Section 3.5(a) is hereby deleted and
is amended in its entirety to read as follows:


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                  (a)      MedPartners Funding Commitment. Subject to the terms
                  and conditions of this Agreement, MedPartners shall be
                  responsible for the satisfaction of (e.g., by payment, offset,
                  or by causing to be paid) the following Provider Claims and
                  Plan Preserved Claims with respect to MPN and the Managed
                  Physician Practices, respectively:

                  2.       The first sentence of subsection (xiii) of Section
3.5(a) is hereby deleted and is amended in its entirety to read as follows:

                           (xiii)   Net Cash Proceeds received by MPN and the
                  Managed Physician Practices, respectively, following the
                  Agreement Date ((xi), (xii) and (xiii) collectively, the
                  "Funding Sources") less Permitted Expenses (as defined below)
                  are, in the aggregate, inadequate to satisfy such Provider
                  Claims and Plan Preserved Claims, assuming that the entire
                  amount of the Funding Sources for MPN and the Managed
                  Physician Practices, respectively, is applied to the
                  satisfaction of such Provider Claims and Plan Preserved
                  Claims.

                  3.       The last two sentences of subsection (c) of Section
3.5 are hereby deleted and are amended in their entirety to read as follows:

                           The funds deposited into the California Account
                  pursuant to this Section shall be used to pay Provider Claims
                  and Plan Preserved Claims as they become payable. In the
                  event the actual amount of applicable Provider Claims and
                  Plan Preserved Claims payable under the MedPartners Funding
                  Commitment with respect to MPN and the Managed Physician
                  Practices, respectively, exceeds the amount deposited
                  hereunder, MedPartners shall fulfill the MedPartners Funding
                  Commitment with respect to such Provider Claims in accordance
                  with Section 3.5(b) above, and with respect to Plan Preserved
                  Claims as provided for in Section 3.5(f) below.

                  4.       Subsection 3.5(d)(2) of the Agreement is amended and
restated in its entirety to read as follows:

                           (2)      In the event the MedPartners Funding
                  Commitment has been satisfied with respect to Provider Claims
                  and Plan Preserved Claims, and there are excess funds in
                  either of the California Accounts, any such excess shall not
                  be subject to withdrawal as excess funds and shall be used to
                  satisfy Provider Claims and Plan Preserved Claims otherwise
                  payable from the other California Account.

                  5.       Subsection 3.5(d)(3)(A) of the Agreement is amended
and restated in its entirety to read as follows:

                           (A)      as to the MPN California Account, when the
                  MedPartners Funding Commitment with respect to MPN Provider
                  Claims and Plan Preserved Claims against MPN has been fully
                  satisfied and there are adequate funds in the MedPartners
                  California Account to fulfill the MedPartners Funding
                  Commitment; and


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                  6.       Subsection 3.5(d)(3)(B) of the Agreement is amended
and restated in its entirety to read as follows:

                           (B) as to the MedPartners California Account, when
                  the MedPartners Funding Commitment with respect to the
                  Managed Physician Practice Provider Claims and Plan Preserved
                  Claims against the Managed Physician Practices has been fully
                  satisfied.

                  7.       Subsection 3.5(d)(4)(A) of the Agreement is amended
and restated in its entirety to read as follows:

                           (A)      The MedPartners Funding Commitment with
                  respect to MPN Provider Claims and Plan Preserved Claims
                  against MPN shall be deemed fully satisfied when an order of
                  the Bankruptcy Court has been entered making such finding,
                  following notice and hearing; and

                  8.       Subsection 3.5(d)(4)(B) of the Agreement is amended
and restated in its entirety to read as follows:

                           (B)      The MedPartners Funding Commitment with
                  respect to the Managed Physician Practice Provider Claims and
                  Plan Preserved Claims against Managed Physician Practices
                  shall be deemed satisfied upon the expiration of five
                  Business Days after the Special Monitor-Examiner gives the
                  Creditors Committee written notice thereof.

                  9.       The Agreement is amended and restated to include a
new Section 3.5(f), which is as follows;

                           (f)      Timing of Payment of Plan Preserved Claims.
                  With respect to each Consenting Plan and pursuant to the
                  MedPartners Funding Commitment, MedPartners shall cause Plan
                  Preserved Claims and Provider Claims held by Consenting Plans
                  to be paid in accordance with Section 20.18 of the
                  Supplemental Plan Agreement.

                  10.      The second sentence of Subsection 3.8(b) of the
Agreement is amended by deleting "December 15, 1999" and replacing it with
"February 15, 2000".

                  11.      Section 7.2(d) of the Agreement is amended and
restated in its entirety to read as follows:

                           Letter of Credit. The Special Monitor-Examiner shall
                  use any proceeds received pursuant to an irrevocable letter
                  of credit solely to fund payment of finally adjudicated and
                  valid Managed Physician Practice Provider Claims and Allowed
                  MPN Provider Claims of Consenting Providers and Consenting
                  Plans. In the event of a draw under the Letter of Credit, the
                  proceeds of such draw shall be made available to holders of
                  such Claims in accordance with this paragraph and
                  subparagraph (d) of the definitions of each of the MPN
                  Provider Release and the MPPP Release even if the draw was
                  triggered by nonpayment of an arbitration


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                  award. All proceeds of any draw shall be allocated between
                  holders of MPN Provider Claims and Managed Physician Practice
                  Provider Claims on the basis of the Special
                  Monitor-Examiner's determination of the respective estimated
                  amount remaining under the MedPartners Funding Commitment.
                  The portion of the draw allocated to MPN Provider Claims
                  shall be deposited into the MPN California Account. If all
                  finally adjudicated and valid Managed Physician Practice
                  Provider Claims of Consenting Providers and Consenting Plans
                  or Allowed MPN Provider Claims of Consenting Providers and
                  Consenting Plans are paid in full, any funds from such draw
                  for such Consenting Providers and Consenting Plans shall be
                  reallocated to be held for the other group of Consenting
                  Providers and Consenting Plans. Any amounts that are drawn
                  under the Letter of Credit by the Special Monitor-Examiner
                  that are not used to make payments on account of the
                  MedPartners Funding Commitment shall be returned to
                  MedPartners after the MedPartners Funding Commitment has been
                  finally satisfied in full. Any funds drawn under the Letter
                  of Credit allocated to the Claims shall be held by the
                  Special Monitor-Examiner in trust until used as provided
                  herein.

                  12.      Subsection 10.1(a) of the Agreement is amended and
restated in its entirety to read as follows:

                           (a)      Except as set forth in Section 10.1(b) or
                  (c) below, the failure of MedPartners to perform, in any
                  material respect, the obligations required to be performed by
                  it under this Agreement; provided, however, that a
                  determination by the Special Monitor-Examiner under Section
                  3.8(d), or the initiation of any arbitration by any
                  Representative under Section 12, shall not constitute the
                  failure by MedPartners to perform its obligations hereunder,
                  in any material respect, but (1) MedPartners failure to pay
                  the amount of any arbitration award under Section 12
                  (including an award obtained pursuant to the procedure set
                  forth in Section 15.14) by reason of such determination or
                  arbitration within five Business Days of such award, or (2)
                  the nonpayment of a Final Preserved Claim in favor of a
                  Consenting Plan in accordance with Section 20.18 of the
                  Supplemental Plan Agreement within five Business Days of the
                  determination of such Final Preserved Claim, shall constitute
                  a Default hereunder.

                  13.      Subsection 10.1(d) of the Agreement is amended and
restated in its entirety to read as follows:

                           (d)      For purposes of this Section 10,
                  MedPartners shall not be deemed to have failed to make a
                  payment or to have satisfied any obligations, where such
                  failure would constitute a Default, during the period that
                  MedPartners or MPN, as applicable, is adjudicating in good
                  faith the nature or amount of the payment or obligation,
                  provided that MedPartners shall fulfill the MedPartners
                  Funding Commitment in connection with any portion of any
                  Provider Claim or Plan Preserved Claim that is not contested
                  or subject to a setoff or recoupment asserted in good faith;
                  provided, however, to the extent any obligation of
                  MedPartners under this Agreement is contingent upon
                  performance by any third party, including satisfaction of any
                  condition precedent to the effectiveness of this


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                  Agreement, it shall not be a Default hereunder if MedPartners
                  fails to complete such obligation despite good faith efforts
                  to do so, by reason of such third party's non-performance.

                  14.      The condition set forth in Section 13.1(b) of the
Agreement is hereby waived.

                  15.      Subsection 15.14(a)(3) of the Agreement is amended
and restated in its entirety to read as follows:

                           (3)      The Plans to seek an order requiring a
                  party to specifically perform its obligations under this
                  Agreement including without limitation the payment of Plan
                  Preserved Claims or Provider Claims held by a Consenting
                  Plan; and

                  16.      Subsection 15.14(b) of the Agreement is amended and
restated in its entirety to read as follows:

                           (b)      Jurisdiction and Representative. Any
                  action under this Section 15.14 against MedPartners for
                  breach of this Agreement may only be brought on behalf of one
                  or more Beneficiaries by a representative of such Beneficiary
                  or group of Beneficiaries in the Los Angeles Superior Court,
                  or, with respect to MPN, the Bankruptcy Court; provided,
                  however, that in the event any Beneficiary asserts that
                  MedPartners or MPN has violated Section 3.5(b), its sole
                  remedy shall be arbitration pursuant to Section 12. The
                  representative in any such action can be any of the
                  following: (i) the Special Monitor-Examiner, (ii) one or more
                  MPN Provider Claim Beneficiaries as designated by the group,
                  (iii) one or more Managed Physician Practice Provider Claim
                  Beneficiaries as designated by the group, (iv) with respect
                  to Beneficiaries holding Managed Physician Practice Provider
                  Claims, a subcommittee of the Creditors Committee
                  representing such Beneficiaries, (v) with respect to
                  Beneficiaries holding MPN Provider Claims, a subcommittee of
                  the Creditors Committee representing such Beneficiaries, (vi)
                  the Creditors Committee, or (vii) a Plan acting on its own
                  behalf or otherwise with respect to its rights under Section
                  15.14(a)(3) (each, a "Representative").

                  17.      Subsection 15.14(c) of the Agreement is amended and
restated in its entirety to read as follows:

                           (c)      Threshold for Enforcement. An action to
                  enforce any right granted to a Beneficiary pursuant to this
                  Section may be commenced only by a Representative in the
                  following circumstances: (i) physician claimants who are
                  eligible Beneficiaries holding in aggregate not less than
                  $600,000 of nonadjudicated Managed Physician Practice
                  Provider Claims; (ii) physician claimants who are eligible
                  Beneficiaries holding in aggregate not less than $300,000 of
                  finally adjudicated Managed Physician Practice Provider
                  Claims; (iii) non-physician claimants who are eligible
                  Beneficiaries holding in aggregate not less than $5 million
                  in non-adjudicated Provider Claims; (iv) non-physician
                  claimants who are eligible Beneficiaries holding an aggregate
                  not less than $5 million in, with respect to the Managed
                  Physician Practices, finally adjudicated and


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                  liquidated Managed Physician Practice Provider Claims and,
                  with respect to MPN, MPN Provider Claims that have become
                  Allowed MPN Claims; or (v) any Plan with respect to its
                  rights under Section 15.14(a)(3). Notwithstanding the
                  foregoing, with respect to eligible Beneficiaries who hold
                  pre-petition MPN Provider Claims, no such enforcement action
                  may be commenced or maintained until the earlier to occur of:
                  (i) the effective date of a confirmed plan of reorganization
                  for MPN in the Bankruptcy Case, or (ii) November 30, 1999.

                  18.      Subsection 15.14(d) of the Agreement is amended and
restated in its entirety to read as follows:

                           (d)      Notice. Prior to bringing an action, the
                  Representative shall give notice of intent to sue to
                  MedPartners, MPN, the Creditors Committee and the Special
                  Monitor-Examiner. Such notice shall provide the name of each
                  eligible Beneficiary within the group and the amount of each
                  such Beneficiary's Provider Claim or Plan Preserved Claim or
                  the provision of the Agreement that such Representative is
                  seeking to enforce. MedPartners and/or MPN, as the case may
                  be, shall have ten Business Days after receipt of such notice
                  to cause such Provider Claims or Plan Preserved Claim to be
                  paid or to comply with the Agreement. If payment or other cure
                  is not made during such cure period, the Representative may
                  proceed with filing the action or initiating the arbitration,
                  as the case may be.

                  19.      Upon the occurrence of the SPA Effective Date (as
defined in the Supplemental Plan Agreement), the provisions of ss. 15.17 of the
Agreement shall be amended and superseded by the Supplemental Plan Agreement;
provided, however, that if the Supplemental Plan Agreement terminates pursuant
to either Section 12.4.1 or 12.6 of the Supplemental Plan Agreement, then
Section 15.17 shall be reinstated.

             The Agreement remains unchanged in all other respects.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date first above written.


                              CAREMARK RX, INC.
                              a Delaware corporation

                              By:      /s/ Edward L. Hardin, Jr.
                                 ----------------------------------------------
                              Title:  Executive Vice President
                                      ---------------------------------------

                              MEDPARTNERS PROVIDER NETWORK, INC.,
                              a California corporation

                              By       /s/ Don Garner
                                 -----------------------------------------------
                              Title   Secretary


                              COMMISSIONER OF THE DEPARTMENT OF
                              CORPORATIONS

                              By: /s/ William Kenefick
                                 -----------------------------------------------
                                      William Kenefick

                              Title:  Acting Commissioner of the Department of
                                      Corporations


                              J. MARK ABERNATHY,
                              as Special Monitor-Examiner and not individually

                              By      /s/  J. Mark Abernathy
                                 -----------------------------------------------
                              Title   J. Mark Abernathy,
                                      as Special Monitor-Examiner


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