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                                                                    Exhibit 10.3

                      PHARMACY BENEFIT MANAGEMENT AGREEMENT

                                     between

                                UNITED HEALTHCARE
                                 SERVICES, INC.

                                       and

                                   MERCK MEDCO
                              MANAGED CARE, L.L.C.


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                      PHARMACY BENEFIT MANAGEMENT AGREEMENT

         This PHARMACY BENEFIT MANAGEMENT AGREEMENT (this "Agreement") is
between UNITED HEALTHCARE SERVICES, INC., on behalf of itself and its affiliates
from time to time, located at 9900 Bren Road East, Minnetonka, Minnesota 55343
(hereinafter "United HealthCare"), and MERCK MEDCO MANAGED CARE, L.L.C. located
at 100 Summit Avenue, Montvale, New Jersey 07645-1753 (hereinafter "PBM"). This
Agreement is effective on the date the parties have each executed it (the
"Effective Date"). It concerns services provided as of the "Commencement Date,"
as hereinafter defined. This Agreement supersedes and replaces any existing
agreements between the parties related to the same subject matter.

                              W I T N E S S E T H:

         WHEREAS, United HealthCare desires to contract with a pharmaceutical
benefits management entity for pharmaceutical benefit management and related
services that United HealthCare will make available, together with other United
HealthCare services, to Health Plans, as hereinafter defined, and other
non-Health Plan business (affiliated with United HealthCare or to which United
HealthCare provides services) through contracts with United HealthCare; and

         WHEREAS, PBM provides pharmaceutical benefits management and related
services and desires to contract with United HealthCare to provide such
management and services.

         NOW, THEREFORE, in consideration of the terms and conditions set forth
in this Agreement, the undersigned parties agree as follows:

         SECTION 1. DEFINITIONS

         1.1. Definitions. In addition to the capitalized terms defined
elsewhere in this Agreement, the following terms shall have the following
meanings:

         (a) "Average Wholesale Price" or "AWP" means the average wholesale
         price of the Covered Prescription Drug Services dispensed, utilizing
         the current price list in the Blue Book and its supplements. If PBM
         ceases to use the Blue Book and its supplements, PBM shall use such
         other nationally recognized pricing source as PBM uses for all of its
         remaining customers; or, if PBM uses more than one source, then the
         source used for United HealthCare shall be the source mutually agreed
         to by the parties. Under the Retail Pharmacy Program, AWP is based on
         the package size submitted. Under the Mail Service Program, AWP is
         based on package sizes of 100 units or 16 oz. quantities, or smaller
         quantities if such quantities are not commercially available.

         (b) "Benefit Contract" means a benefit plan that: (i) is sponsored,
         purchased, issued or administered by Payor and (ii) contains the terms
         and conditions of a Covered Person's coverage. A Benefit Contract is
         also known as a certificate of coverage, summary plan description,
         evidence of coverage, or group services agreement.

         (c) "Commencement Date" means June 1, 2000 or such earlier date on
         which PBM begins to provide services under this Agreement in accordance
         with Section 3.24.



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         (d) "Copayment or Coinsurance or Deductible or Other Charge"
         collectively known as "Copayment" means the charge, in addition to the
         premium, which a Covered Person is required to pay for certain covered
         services provided under the Benefit Contract and Pharmacy Rider.
         Copayment or Coinsurance or Deductible or Other Charge may be either a
         defined dollar amount or a percentage of eligible expenses. A Covered
         Person is responsible for the payment of any Copayment directly to the
         pharmacy at the time the prescription is dispensed.

         (e) "Covered Person" means an individual eligible to receive coverage
         for outpatient prescription pharmacy benefits who is currently enrolled
         under a United HealthCare or Payor Benefit Contract that includes a
         Pharmacy Rider.

         (f) "Covered Prescription Drug Services" means those covered outpatient
         prescription drugs and covered pharmacy products, services and supplies
         pursuant to a Covered Person's Benefit Contract and/or Pharmacy Rider.

         g) "Health Plan" means a licensed health maintenance organization
         ("HMO") or other similar organization that is either (i) owned by
         United HealthCare where "Owned" means that United HealthCare owns not
         less than a majority of the voting securities; or (ii) managed by
         United HealthCare, where "Managed" means that United HealthCare manages
         the pharmacy program or provides other management or administrative
         services such as claims processing services, where the local managed
         health plan assumes medical risk other than as defined below. Health
         Plan includes an HMO or other similar organization Owned or Managed
         that offers an array of products including but not limited to
         fully-insured, self-insured products (where such self-insured products
         use the provider networks, medical management and other similar
         services used by the HMO or similar organization), commercial HMO
         products, Medicare risk products (Medicare+ Choice), Medicaid, EPO
         products, PPO products, and all combination products that include an
         in-network and out-of-network component such as point-of-service
         ("POS") products. When such organization is Managed by United
         HealthCare, not Owned by United HealthCare, Health Plan includes such
         organization only to the extent it has elected to receive services
         pursuant to this Agreement. The term Health Plan is not intended to
         include: (i) United HealthCare Insurance Company (UHI) products unless:
         (A) such products use provider networks, medical management and other
         similar services in a manner comparable to the HMOs or similar
         organization; and (B) United HealthCare is responsible for medical
         underwriting risk; or (ii) fully insured or self-funded products sold
         through United HealthCare's Strategic Business Services division; or
         (iii) Medicare supplemental products (MediGap); or (iv) the consumer
         funded pharmacy program addressed in Section 3.18 of this Agreement.

         (h) "Intellectual Property" means all patents, patents pending,
         trademarks, service marks, trade names, service names, slogans,
         registered copyrights, commercially significant unregistered
         copyrights, technology rights and licenses, computer software
         (including, without limitation, any source or object codes or related
         documentation), trade secrets, franchises, know-how, and inventions and
         all improvements to such intellectual property.

         (i) "Mail Service Program" means a program contemplated by this
         Agreement in which Covered Persons may mail a prescription together
         with the applicable Copayment to PBM for dispensing of a 90 day maximum
         supply of a covered drug via mail service.



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         (j) "Maximum Allowable Cost" or "MAC" means a list established by PBM
         for its book of business showing the maximum allowable cost for a list
         of prescription drug ingredients. Any generic or branded generic drug
         on the MAC list dispensed at retail will be reimbursed at the maximum
         allowed by such list.

         (k) "Participating Pharmacy" means a pharmacy, including a retail or
         mail service pharmacy, which has entered into an agreement with PBM
         under which pharmacy has agreed to provide Covered Prescription Drug
         Services to Covered Persons and to comply with (i) contractual
         requirements pursuant to this Agreement; and (ii) regulatory
         requirements.

         (l) "Payor" means United HealthCare or the entity or person that has
         the financial responsibility to United HealthCare for payment for
         services covered by a Benefit Contract and/or Pharmacy Rider.

         (m) "Pharmacy Rider" means that rider to the Covered Person's Benefit
         Contract that in addition to the Benefit Contract, states the details
         of Covered Person's prescription drug coverage. The Benefit Contract
         and Pharmacy Rider are used by PBM in processing outpatient
         prescription drug claims in connection with this Agreement.

         (n) "Pharmacy & Therapeutics Committee" or "P&T Committee" means that
         United HealthCare committee that: (i) reviews a prescription drug for
         inclusion on the United HealthCare Preferred Drug List or other
         comparable formularies; and, (ii) develops other criteria, procedures
         and rules for the Program including but not limited to quantity level
         and prior authorization.

         (o) "Preferred Drug List" or "PDL" means a list that identifies those
         Federal Drug Administration ("FDA") approved prescription drug products
         that are preferred by United HealthCare for dispensing to Covered
         Persons.

         (p) "Program" means all pharmacy services provided under the Benefit
         Contract and Pharmacy Rider to Covered Persons, including days supply
         limitation, Copayment, Preferred Drug List and other program
         specifications set forth in this Agreement or otherwise agreed to, in
         writing, between or among the parties.

         (q) "PDL Rebate(s)" means those monies received by PBM through PBM's
         rebate contracts with pharmaceutical manufacturers as a result of
         inclusion of such manufacturer's drugs on the PDL, which monies are
         paid to and earned by United HealthCare pursuant to Section 5.5 and its
         subparts.

         (r) "Retail Pharmacy Program" means that part of the pharmacy program
         where Covered Persons may purchase a maximum of a 34 day supply (except
         as otherwise mutually agreed) of Covered Prescription Drug Services
         from a retail Participating Pharmacy upon providing verification of
         eligibility and payment of the applicable Copayment.

         (s) "Substantial Change" means a change in law or regulation applicable
         to a party to this Agreement that materially adversely affects the
         benefits such party reasonably expected to receive under this
         Agreement.



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         (t) "United HealthCare" means the party to this Agreement or another
         wholly owned affiliate, subsidiary or business division to whom United
         HealthCare may assign this Agreement.

SECTION 2.  REPRESENTATIONS AND WARRANTIES

         2.1.     Representations and Warranties of PBM.

                  2.1.1. Organization and Qualification. PBM represents and
                  warrants to United HealthCare that it is a limited liability
                  company duly organized, validly existing and in good standing
                  under the laws of New Jersey. PBM has the corporate power and
                  authority necessary to own and operate its properties and to
                  carry on its business as now conducted. PBM is qualified to do
                  business as a foreign corporation in every jurisdiction in
                  which the nature of its business and/or its ownership of
                  property requires it to be so qualified.

                  2.1.2. Corporate Authorization. PBM represents and warrants to
                  United HealthCare that the execution, delivery, and
                  performance of this Agreement and the provision of the
                  services contemplated hereby are within its corporate powers.
                  All requisite authority necessary to enter into this Agreement
                  has been obtained, and PBM has duly and validly executed and
                  delivered this Agreement. Assuming this Agreement constitutes
                  the valid and binding agreement of United HealthCare, this
                  Agreement constitutes a valid and binding agreement of PBM
                  enforceable against PBM in accordance with its terms.

                  2.1.3. No Conflict; Required Filings and Consents. PBM
                  represents and warrants to United HealthCare that the
                  execution, delivery and performance of this Agreement does
                  not, and the provision of the services contemplated hereby
                  will not: (a) conflict with the Articles of Organization or
                  Bylaws of PBM; (b) conflict with or violate any laws
                  applicable to PBM or by which any of its properties is bound
                  or affected; or (c) result in any breach of or constitute a
                  default (or an event that with notice or lapse of time or both
                  would become a default) under, or give to others any rights of
                  termination, amendment, acceleration or cancellation of, or
                  result in the creation of a lien or encumbrance on any of the
                  properties or assets of PBM pursuant to any note, bond,
                  mortgage, indenture, contract, agreement, lease, license,
                  permit, franchise or other instrument or obligation to which
                  PBM is a party, or by which PBM or any of its properties is
                  bound or affected. The execution and delivery of this
                  Agreement by PBM does not, and the performance of this
                  Agreement by PBM and the provision of the services
                  contemplated hereby by PBM will not, require any consent,
                  approval, authorization or permit of, or filing with or
                  notification to, any third party, except for certain filings
                  required by certain state governmental entities.

         2.2.     Representations and Warranties of United HealthCare.

                  2.2.1. Organization and Qualification. United HealthCare
                  represents and warrants to PBM that it is a corporation duly
                  incorporated, validly existing and in good standing under the
                  laws of Minnesota. United HealthCare has the corporate power
                  and authority necessary to own and operate its properties and
                  to carry on its business as now conducted. United HealthCare
                  is qualified to do



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                  business as a foreign corporation in every jurisdiction in
                  which the nature of its business or its ownership of property
                  requires it to be so qualified.

                  2.2.2. Corporate Authorization. United HealthCare represents
                  and warrants to PBM that the execution, delivery, and
                  performance of this Agreement are within its corporate powers.
                  All requisite authority necessary to enter into this Agreement
                  has been obtained, and United HealthCare has duly and validly
                  executed and delivered this Agreement. Assuming this Agreement
                  constitutes the valid and binding agreement of PBM, this
                  Agreement constitutes a valid and binding agreement of United
                  HealthCare enforceable against United HealthCare in accordance
                  with its terms.

                  2.2.3. No Conflict; Required Filings and Consents. United
                  HealthCare represents and warrants to PBM that the execution,
                  delivery and performance of this Agreement does not, and the
                  performance of this Agreement by United HealthCare will not:
                  (a) conflict with the Articles of Incorporation or Bylaws of
                  United HealthCare; (b) conflict with or violate any laws
                  applicable to United HealthCare or by which any of its
                  properties is bound or affected; or (c) result in any breach
                  of or constitute a default (or an event that with notice or
                  lapse of time or both would become a default) under, or give
                  to others any rights of termination, amendment, acceleration
                  or cancellation of, or result in the creation of a lien or
                  encumbrance on any of the properties or assets of United
                  HealthCare pursuant to any note, bond, mortgage, indenture,
                  contract, agreement, lease, license, permit, franchise or
                  other instrument or obligation to which United HealthCare is a
                  party, or by which United HealthCare or any of its properties
                  is bound or affected. The execution and delivery of this
                  Agreement by United HealthCare does not, and the performance
                  of this Agreement by United HealthCare will not, require any
                  consent, approval, authorization or permit of, or filing with
                  or notification to any third party, except for certain filings
                  required by certain state governmental entities.

SECTION 3. OBLIGATIONS OF PBM: PHARMACY MANAGEMENT AND SERVICES

         3.1. General PBM Services. PBM shall provide to United HealthCare the
         services described in this Agreement and in Exhibit A. PBM acknowledges
         that its position as a premier company capable and desirous of
         providing industry leading products and services is an inducement on
         which United HealthCare is relying in entering into this Agreement.

         3.2. Laws, Regulations and Licenses. PBM, at its own cost, shall: (a)
         maintain all federal, state, and local licenses that are materially
         necessary to provide services under this Agreement and the lack of
         which could adversely affect United HealthCare; (b) shall comply with
         all applicable statutes and regulations in providing all services
         pursuant to this Agreement; and (c) require all Participating
         Pharmacies employed by or under contract with PBM to comply with (a)
         and (b).

         3.3. Personnel and Other Resources. PBM shall provide sufficient,
         dedicated personnel, information systems support and other resources,
         as reasonably required to successfully administer a high quality,
         cost-effective Program for United HealthCare pursuant to this
         Agreement. PBM and United HealthCare shall review the



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         appropriateness of resource allocation on a regular basis, no less
         often than quarterly. United HealthCare has the right to interview and
         approve of any recommended new hires for the Dedicated Pharmacy
         Management Unit discussed below. United HealthCare also has the right
         to have a PBM employee removed from providing services for United
         HealthCare. PBM shall be responsible for all compensation, benefits and
         taxes of PBM's employees. If the parties agree to locate any PBM
         employees at a United HealthCare location, United HealthCare shall be
         responsible to provide workspace, supplies and equipment to PBM within
         a mutually agreed upon reasonable time frame and at a mutually agreed
         upon cost.

                  3.3.1. PBM agrees to have a Dedicated Pharmacy Management Unit
                  located in Minneapolis as part of the pharmacy management
                  services provided for United HealthCare. PBM agrees to have
                  this unit fully operational prior to the Commencement Date.
                  United HealthCare will designate the name of this dedicated
                  unit, subject to the approval of PBM.

                  3.3.2. PBM agrees that the senior management team dedicated to
                  United HealthCare shall be located in Minneapolis and shall
                  consist of a senior level employee who has decision-making
                  authority. In addition to general PBM management expertise,
                  PBM shall have individuals located in the Dedicated Pharmacy
                  Management Unit with expertise in: (a) clinical and analytical
                  services, (b) customer account services, (c) marketing and
                  sales support, (d) pharmacists to work with the Health Plans,
                  and (e) account management for Health Plan and non-Health Plan
                  business. PBM shall also provide the following support to the
                  Dedicated Pharmacy Management Unit's activities for United
                  HealthCare from PBM's corporate or other offices: customer
                  service, legal and regulatory compliance, information systems,
                  network management, operational support, underwriting,
                  manufacturer activity and clinical programs.

                  3.3.3. PBM agrees that the services provided by PBM's
                  dedicated pharmacy management services include: (a) work with
                  United HealthCare to position United HealthCare's prescription
                  drug Programs for economic and service success in a changing
                  competitive market place; (b) formulate appropriate pharmacy
                  goals with and for United HealthCare; (c) develop and execute
                  a pharmacy marketing plan that will enable United HealthCare
                  to meet its sales and growth goals; and (d) help with pharmacy
                  cost management including United HealthCare's trend management
                  and per member per month (pmpm) cost management.

                  3.3.4. PBM agrees to provide dedicated management and sales
                  support as reasonably requested to optimize the value of
                  United HealthCare's Program and to attain United HealthCare's
                  identified goals. PBM's marketing and sales support shall
                  include but not be limited as the market changes from time to
                  time, to the following: (a) strategic consultation, training
                  and education; (b) advanced training modules for sales
                  representatives; (c) continuing education programs; (d) site
                  visits and video presentations; (e) focus groups and related
                  consulting; (f) press release development and recommendations;
                  (g) strategies to successfully market against competitors; (h)
                  presentation and reference materials for use by sales
                  representatives; (i) client sales support during finalist
                  presentations; (j) professionally designed marketing
                  literature that effectively positions United HealthCare and
                  communicates the clients' prescription benefit programs; and
                  (k) customized communication programs to motivate and inform
                  selected audiences.



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                  3.3.5. PBM agrees that different marketing strategies will be
                  provided to United HealthCare for growth goals based on
                  revenue, profit, and membership.

         3.4. Retail Participating Pharmacy Network. PBM agrees to provide
         national networks of retail Participating Pharmacies under contract
         with PBM to provide dispensing services to Covered Persons under the
         Retail Pharmacy Program. PBM agrees that United HealthCare may require
         the termination of a specific retail pharmacy for good cause including
         quality of care issues. PBM shall notify United HealthCare of any
         terminations in the Participating Pharmacy network. PBM shall send
         letters to Covered Persons, who have utilized a Participating Pharmacy
         in the prior twelve months, notifying them of the termination of such
         Participating Pharmacy, after receiving from United HealthCare: (a) the
         addresses of the affected Covered Persons; and (b) the approval of the
         letters by United HealthCare. United HealthCare shall be responsible
         for the postage costs of any mailings to Covered Persons when a
         Participating Pharmacy is terminated at United HealthCare's request.
         PBM shall be responsible for the postage costs of any mailings to
         Covered Persons when Participating Pharmacy is terminated at PBM's
         request.

                  3.4.1. PBM will provide United HealthCare with at least three
                  network alternatives by the Commencement Date as described in
                  the Financial Appendix:

                           3.4.1.1. PBM shall provide and maintain a
                           Participating Provider network that is taken as a
                           whole no less favorable in terms of number, location,
                           and quality of providers than the network available
                           to United HealthCare as of the period just prior to
                           the Commencement Date and PBM shall guarantee no
                           deterioration in reimbursement during the term of
                           this Agreement as compared to the period just prior
                           to the Commence Date. This network may upon parties'
                           mutual written consent be contracted through United
                           HealthCare.

                           3.4.1.2. PBM shall make available its CCNIII network.

                           3.4.1.3.  PBM shall make available its CCN+ network.

                  3.4.2. PBM agrees to use reasonable commercial efforts to
                  create alternative retail networks for any new products or
                  other offerings that may be developed by United HealthCare
                  from time to time.

                  3.4.3. For the network described in Section 3.4.1.1, PBM
                  agrees that during the term of this Agreement all PBM
                  customized pharmacy provider agreements for such retail
                  pharmacy network shall be assignable to United HealthCare.
                  Such assignment shall be made at United HealthCare's sole
                  discretion and at a time determined by United HealthCare.

         3.5. Mail Service. PBM shall provide to United HealthCare and Health
         Plans shall use PBM's mail service program as its exclusive mail
         service program, as more fully described in the Financial Appendix.
         United HealthCare shall use its reasonable commercial efforts to
         encourage non-Health Plan business to use PBM's mail service. PBM
         agrees to interface with other mail service vendors utilized by
         non-Health Plan business as reasonably requested using PBM's
         specifications.



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         3.6. Customized Installation Materials. PBM agrees to provide to United
         HealthCare customized installation materials for United HealthCare that
         are accurate and support the specific language in the Benefit Contract
         and Pharmacy Rider. PBM is responsible for administering the Benefit
         Contract and Pharmacy Rider accurately and in accordance with all
         regulatory requirements. At United HealthCare's option and approval,
         PBM shall produce brochures, and other Covered Person materials for
         Covered Persons specific to Covered Prescription Drug Services. PBM
         agrees to provide an accompanying explanatory brochure and direct
         reimbursement claim forms for use by Covered Persons who have not
         received or who have lost their Identification Cards. PBM agrees that
         any Covered Person materials must be approved by United HealthCare.
         United HealthCare shall be responsible for all postage costs related to
         mailings to Covered Persons except as otherwise provided in this
         Agreement.

         3.7. Eligibility. PBM agrees to administer eligibility of Covered
         Persons according to eligibility information provided by United
         HealthCare via tape or telecommunication or such other reasonably
         practicable method in a mutually agreeable acceptable format. PBM
         agrees to provide toll-free access for Covered Persons to PBM's
         Customer Service Department for eligibility and claims processing
         assistance. PBM may rely on eligibility information provided by United
         HealthCare for all purposes related to this Agreement.

         3.8. Covered Person Protection Provision. PBM hereby agrees that it
         shall not seek payment, other than Copayments, from any Covered Person
         for Covered Prescription Drug Services under any circumstances. This
         Section shall survive the Agreement.

         3.9. Communications. PBM agrees that all written communications sent to
         United HealthCare Covered Persons, participating providers or
         facilities that relate in any way to United HealthCare's Benefit
         Contract or Pharmacy Rider must be reviewed and approved by United
         HealthCare before such communications are sent out to any such
         individuals or groups. PBM agrees that all program communication
         protocols to be used with United HealthCare participating physician
         providers will be reviewed and approved by United HealthCare prior to
         use. United HealthCare shall approve or disapprove all such materials
         within a reasonable time after submission by PBM.

         3.10.    Claims Processing.

                  3.10.1. PBM shall process Covered Persons' Covered
                  Prescription Drug Services claims in accordance with
                  regulatory requirements, the Benefit Contract and Pharmacy
                  Rider, and PBM's standard operating procedure.

                  3.10.2. At the end of each bi-weekly claims cycle, or other
                  processing time period as mutually agreed to by the parties,
                  PBM shall provide claims reports and written notice to United
                  HealthCare of the amount necessary to pay claims processed and
                  fees due to PBM for claims processed.

                  3.10.3. Any disputes over claims shall be resolved prior to
                  payment by PBM. If PBM makes an error or omission in claims
                  processing, PBM shall be solely responsible for any related
                  costs.



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                  3.10.4. All postage costs related to payment or denial of
                  direct reimbursement claims is the responsibility of PBM.

         3.11. Claim Appeals. In the event of a claim denial by PBM, PBM shall
         promptly communicate to the Covered Person the right to appeal
         according to the Covered Person's Benefit Contract and Pharmacy Rider
         and applicable law.

         3.12. Claims and Pharmacy Auditing. PBM shall regularly audit its
         electronic and on-site claim processing activities and shall regularly
         audit its retail pharmacies, in accordance with PBM's standard audit
         procedures. PBM shall provide United HealthCare with a report on such
         audits containing specific audit information and containing such other
         information as United HealthCare reasonably requests. United HealthCare
         shall receive one hundred percent of any such audit recoveries that
         were incorrectly paid pursuant to the United HealthCare Program. When
         any such overpayment was the result of errors or omissions by PBM,
         payment of such audit recovery shall include interest at the prevailing
         prime rate of interest as determined by the Wall Street Journal for the
         period of time from the payment of the claim to receiving recovery from
         PBM.

         3.13. Reports. PBM agrees to provide aggregate reports and
         Payor-specific reports in a format and containing such information as
         United HealthCare reasonably requests; provided in no event shall PBM
         be required to incur costs substantially in excess of expenses incurred
         by the PBM industry generally to provide such reports. This reporting
         shall include PBM's EXPERxT and Standard PLUS Reports and reports
         pursuant to Exhibit A.

         3.14. Coordination of Benefits. When United HealthCare provides
         required information, PBM agrees to process Level I and II coordination
         of benefits in accordance with PBM's coordination of benefits rules.

         3.15. Health Management Program. PBM agrees to provide Health
         Management Programs to Covered Persons at United HealthCare's option.
         Health Management Programs developed during the term of this Agreement
         by PBM shall be made available to United HealthCare. * At United
         HealthCare's reasonable request, PBM will work with United HealthCare
         to obtain incremental funding from pharmaceutical companies for such
         Health Management Programs as mutually agreed. * If United HealthCare
         requests assistance to develop its own health management program, PBM
         shall assist United HealthCare in obtaining external funding for
         development. At United HealthCare's option and if PBM is willing, PBM
         shall develop with United HealthCare and shall share revenues with
         United HealthCare on any programs involving health management, outcome
         research, clinical trials development and post market surveillance.
         Nothing in this section requires United HealthCare to utilize PBM's
         Health Management Program or prohibits United HealthCare from
         developing or seeking funding for health management programs and other
         related programs outside of PBM and this Agreement.

         3.16. Physician-based Pharmaceutical Care Application Information
         System. PBM agrees to fund * by end of year 2002, for the development
         and implementation of a pharmaceutical care application of physician
         based information systems in conjunction


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



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         with United HealthCare, utilizing mutually agreed upon vendors. This
         systems program shall be a knowledge-based system for physicians which
         includes but is not limited to PDL compliance and drug compatibility
         capabilities.

         3.17. Demand Management Services. PBM agrees to utilize reasonable
         efforts to contract exclusively with United HealthCare for Demand
         Management Services by the Commencement Date. *

         3.18. Consumer Funded Pharmacy Program. PBM will develop, in
         conjunction with United HealthCare, a consumer funded pharmacy program,
         also known as a 100% copayment program for primary use with United
         HealthCare's seniors' division. PBM will use reasonable efforts to have
         such program generally include the aspects of: (a) pharmacy network
         discounts; and (b) PDL Rebates, together with such other provisions as
         the parties mutually agree. PBM agrees this product shall be developed
         by July 1, 1999. PBM agrees that such program developed specifically
         for United HealthCare will be for the exclusive use of United
         HealthCare.

         3.19. National Accounts. The parties agree to use reasonable commercial
         efforts to work together to increase joint pharmacy National Account
         business. United HealthCare agrees to utilize PBM as United
         HealthCare's exclusive PBM for National Accounts to the extent required
         under Section 9. * Both parties will agree to mutually acceptable rules
         and protocols regarding the quoting of mutual current clients and
         future prospects. Both parties agree to use reasonable commercial
         efforts to address special and unique administrative requirements of
         National Account clients and prospects. By the Commencement Date and
         during the term of this Agreement, the parties agree to work together
         to establish performance standards and guarantees for National Account
         clients including customized performance standards when appropriate.

         3.20. Service Performance Standards. United HealthCare and PBM shall
         each use good faith and reasonable commercial efforts to perform their
         respective duties and obligations in a diligent, professionally
         responsible and efficient manner. The parties agree to cooperate with
         and assist each other as reasonably necessary in the performance of
         their respective duties and in developing timely responses to the needs
         of United HealthCare's business. Notwithstanding the general and
         specific Service Performance Standards and Guarantees applicable to PBM
         identified in Exhibit B, PBM shall perform the services for which it is
         responsible under this Agreement using the same degree of skill and
         care in such performance as a prudent person engaged in pharmacy
         benefit management services would use under substantially similar
         circumstances in the management of a similar pharmacy benefit
         management business of United HealthCare's magnitude. PBM agrees to
         accept the Service Performance Standards and Guarantees set forth in
         Exhibit B, including the dollars which shall be at risk should PBM's
         aggregate performance or guarantees be below the indicated targets. PBM
         shall provide to United HealthCare: (a) monthly or quarterly reports as
         applicable of PBM's performance; and (b) annual statistics, within
         ninety (90) days of the end of the calendar year, demonstrating whether
         PBM met the Service Performance Standards and Guarantees described in
         Exhibit B. At the same time PBM provides such statistics to


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.


                                       10

<PAGE>



         United HealthCare, PBM shall reimburse United HealthCare any monies
         owed because of PBM's failure to meet such Service Performance
         Standards and Guarantees.

         3.21. Insurance. PBM shall procure by the Effective Date and shall
         maintain, at its own expense: (a) professional liability insurance in
         the amount of $5,000,000.00 per occurrence and $10,000,000.00 annual
         aggregate including coverage for errors and omissions; (b) general
         liability insurance in the amount of $1,000,000.00 per each occurrence
         and $3,000,000.00 annual aggregate; and (c) umbrella/excess liability
         insurance in the amount of $10,000,000.00 each occurrence and
         aggregate. United HealthCare must be named as an "additional insured"
         on the policies referenced above for claims affecting United
         HealthCare's interests.

         3.22. Guaranty. PBM's and United HealthCare's parent corporations will
         guaranty the fulfillment of all of the parties' financial and other
         obligations by the delivery of a fully executed Guaranty Agreement in
         the form set forth at Attachment 1 and Attachment 2.

         3.23. Claims and Regulatory Inquiries. PBM shall promptly, within ten
         (10) days, provide information to United HealthCare about all
         non-routine inquiries by regulatory departments, pharmaceutical
         manufacturers, attorneys, Covered Persons, or other individuals or
         entities with respect to PBM's services pursuant to this Agreement
         including but not limited to the denial of any claims or any causes of
         action.

         3.24. *

SECTION 4. OBLIGATIONS OF UNITED HEALTHCARE

         4.1.     Obligations of United HealthCare.

                  4.1.1. United HealthCare will be the entity that contracts
                  with Health Plans and non-Health Plans related to the services
                  provided under this Agreement. Non-Health Plans include but
                  are not limited to entities, groups, competitors and
                  individuals. Such agreements between United HealthCare and
                  Health Plans and non-HealthPlans may provide for additional
                  services by United HealthCare and shall make provision for
                  fees and other terms that United HealthCare, in its
                  discretion, determines to establish.

                  4.1.2. United HealthCare agrees to provide information
                  reasonably needed by PBM to administer its responsibilities
                  under this Agreement including (a) Benefit Contract and
                  Pharmacy Rider documents; (b) timely eligibility and
                  enrollment data on Covered Persons; (c) specific United
                  HealthCare customer information and needs; (d) participating
                  pharmacy information when PBM's pharmacy network is not
                  utilized or is used in addition to another participating
                  pharmacy network; (e) patient identifiable prescription drug
                  claims (including prescription drug claims from prior pharmacy
                  benefit management vendors); and (f) patient identifiable
                  medical claims reasonably necessary for PBM to implement and


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



                                       11

<PAGE>


                  operate its clinical management programs for United
                  HealthCare. Information shall be provided in a mutually
                  agreeable format.

                  4.1.3. United HealthCare or Payor shall be solely responsible
                  for drafting United HealthCare's Benefit Contract and Pharmacy
                  Rider.

                  4.1.4. United HealthCare shall identify its targeted pharmacy
                  growth and benefit objectives on at least an annual basis and
                  provide such objectives to PBM.

         4.2. Claims Payment. United HealthCare shall establish a bank
         account(s) (the "Program Account") from which PBM will make claims
         payments as set forth below, using United HealthCare check stock.
         United HealthCare will pay PBM Administrative Fee payments, as set
         forth below through Automated Clearing House transfer. Banking
         arrangements may change from time to time subject to the mutual
         agreement of the parties.

                  4.2.1. Claims. PBM shall provide United HealthCare with a
                  bi-weekly consolidated statement of expected payments to be
                  made from the Program Account for services provided by PBM
                  under the Program during such claim cycle, in accordance with
                  the Program Pricing set forth Provisions 1 and 2 of the
                  Financial Appendix.

                  4.2.2. Administrative Fees. PBM will provide United HealthCare
                  with an Administrative Fee statement in accordance with PBM's
                  four (4) week administrative fee cycle pursuant to Provision 3
                  of the Financial Appendix. Within two (2) days after receipt
                  of each statement from PBM as set forth in this Section 4.2.2
                  above, United HealthCare shall transfer such funds via
                  Automated Clearing House transfer.

         4.3. Regulatory Compliance. United HealthCare shall (a) maintain all
         material federal, state, and local licenses that are reasonably
         required to operate its business; (b) comply with all material
         applicable statutes and regulations; and, (c) make reasonable
         commercial efforts to cause Health Plans to comply with (a) and (b).

         4.4. Insurance. United HealthCare agrees to maintain adequate insurance
         related to the operation of its business and its obligations under the
         Agreement.

         4.5. Claims and Regulatory Inquiries. United HealthCare shall promptly
         provide information to PBM within ten days about all non-routine
         inquiries by regulatory departments, pharmaceutical manufacturers,
         Covered Persons, or other individuals or entities with respect to the
         services provided by PBM under this Agreement.

         4.6. Minimum PDL Enrollment. United HealthCare agrees that it shall
         maintain a minimum of * Health Plan Covered Persons and * non-Health
         Plan Covered Persons receiving services under this Agreement including
         participating in United HealthCare's PDL by January 1, 2001 and
         throughout the term of this Agreement. *


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



                                       12

<PAGE>


SECTION 5. MUTUAL OBLIGATIONS

5.1. Pharmacy Strategic Council. United HealthCare and PBM shall create a
Pharmacy Strategic Council ("Strategic Council"), the members of which shall be
three or four representatives from and designated by each of United HealthCare
and PBM. The Strategic Council shall meet no less frequently than quarterly
throughout the term of this Agreement and shall be responsible for (a)
overseeing the performance of the parties under this Agreement; (b) enhancing
communication of decisions made by the parties or the Strategic Council, (c)
resolving disputes as directed by this Agreement; and (d) establishing a forum
for the discussion of common strategic objectives of United HealthCare and PBM.
United HealthCare shall be responsible to convene meetings of the Strategic
Council.

5.2. Expenses. Except as expressly set forth in this Agreement, each of the
parties shall bear the expenses incurred by it in connection with its
performance under this Agreement.

         5.3.     Audits.

                  5.3.1. United HealthCare shall keep reasonable documentation
                  of all Covered Persons related to this Agreement. PBM shall
                  have the right to review such data at reasonable times upon
                  reasonable notice

                  5.3.2. PBM shall maintain adequate medical, financial and
                  administrative records related to Program services in a manner
                  consistent with the standards of the community and in
                  accordance with all applicable statutes and regulations
                  including, but not limited to, reasonable documentation of all
                  the data of Covered Persons related to PBM's services under
                  this Agreement to determine that PBM is performing its
                  obligation under the Agreement and correctly billing United
                  HealthCare. United HealthCare shall have the right to review
                  such data at reasonable times and upon reasonable notice. If
                  any audit reveals an underpayment or overpayment by United
                  HealthCare to PBM such discrepancy will be reported to PBM and
                  PBM will respond within forty-five (45) days. Any amounts PBM
                  deemed payable as a result thereof shall be promptly repaid to
                  the appropriate party with accrued interest (whether or not
                  this Agreement has terminated). If the parties disagree on the
                  amount to be repaid, the matter shall be sent to the Strategic
                  Council. This obligation shall survive the expiration or
                  earlier termination of this Agreement.

                  5.3.3. PBM's agreements with pharmaceutical manufacturers are
                  subject to confidentiality agreements. Any audit of PBM's
                  agreements with pharmaceutical manufacturers conducted
                  pursuant to this Agreement, shall be conducted by a third
                  party public accounting firm reasonably acceptable to PBM
                  whose audit department is a separate stand alone function of
                  its business, subject to execution of a confidentiality
                  agreement, and shall include only those portions of such
                  pharmaceutical manufacturer agreements as necessary to
                  determine PBM's compliance with Section 5.5.2 in respect to
                  PDL Rebates.

         5.4. Preferred Drug List. Beginning on the Commencement Date and
         continuing through the term of this Agreement, PBM shall administer the
         United HealthCare PDL or other formularies as developed by United
         HealthCare from time to time pursuant to the



                                       13

<PAGE>


         Benefit Contract, Pharmacy Rider and this Agreement. All Health Plans
         shall participate in the PDL unless otherwise agreed, in writing, by
         United HealthCare and PBM. United HealthCare agrees to make reasonable
         commercial efforts to have non-Health Plan business utilize this PDL.

                  5.4.1. United HealthCare Preferred Drug List. The Preferred
                  Drug List ("PDL") is a list that identifies those Federal Drug
                  Administration ("FDA") approved prescription drug products
                  that are preferred by United HealthCare for dispensing to
                  Covered Persons.

                           5.4.1.1. United HealthCare and its P&T Committee have
                           complete control in deciding what prescription drugs
                           are placed on the PDL from time to time.

                           5.4.1.2 PBM shall have the right to present clinical
                           data and rationale to the P&T Committee in
                           conjunction with its evaluation of prescription
                           drugs, but shall not be a voting member of the P&T
                           Committee.

                  5.4.2. Preferred Drug List Compliance. United HealthCare has
                  in effect certain Program features designed to promote
                  prescribing of PDL drugs by participating providers,
                  dispensing of PDL drugs by Participating Pharmacies, and
                  awareness of the advantages of the PDL by Covered Persons.
                  Such features include, but are not limited to, incented
                  benefit plan designs and corresponding levels of Copayments.
                  United HealthCare shall notify PBM, in advance, of any
                  proposed Program modifications that are reasonably anticipated
                  to have a material effect on PDL compliance. Additionally,
                  United HealthCare shall participate in PBM's formulary
                  communications programs, which may include communications with
                  United HealthCare Covered Persons, Participating Pharmacies
                  and/or physicians, and financial incentives to Participating
                  Pharmacies for their participation in the PDL. PBM shall
                  notify United HealthCare, in advance, of all PDL
                  communications programs. United HealthCare shall approve and
                  may make reasonable changes to the content of such PDL
                  communication programs before they are provided to the above
                  United HealthCare groups and individuals.

                  5.4.3. Exclusive PDL Administration. Beginning on the
                  Commencement Date, United HealthCare agrees that PBM will be
                  the exclusive administrator of the United HealthCare PDL for
                  those entities covered by the exclusivity requirements of
                  Section 9 of this Agreement. After the Commencement Date,
                  United HealthCare agrees not to accept any funds the receipt
                  of which would influence the selection of prescription drugs
                  for inclusion on United HealthCare's PDL without the express
                  written consent of PBM.

         5.5. PDL Rebate Program. Pursuant to agreements entered into between
         PBM and certain pharmaceutical manufacturers ("Manufacturer
         Agreements"), PBM receives PDL Rebates from certain drug manufacturers
         as a result of the inclusion of such manufacturer's branded products on
         the PDL ("PDL Rebates"). PBM will assure that United HealthCare
         receives PBM's most favorable applicable PDL Rebates as compared to
         other PBM customers based upon comparable PDL configuration. PBM shall
         pay United HealthCare *of the estimated PDL Rebates earned by PBM based
         on the dispensing of each such manufacturer's prescription drugs under
         United

     ----------

     *    Represents text deleted pursuant to a confidentiality treatment claim
          filed with the Securities and Exchange Commission pursuant to Rule 406
          under the Securities Act of 1933, as amended.

                                       14

<PAGE>



         HealthCare's Program *. United HealthCare acknowledges that PBM also
         receives and retains additional rebates and/or fees from certain
         manufacturers which may take into account various factors including the
         utilization of certain drugs within their respective therapeutic
         categories for PBM's book of business in aggregate as a result of
         various commitments, services and programs including, but not limited
         to, formularies, e.g. cost effective, incentive, volume, and
         market-share rebates.

                  5.5.1. Guaranteed PDL Rebates. PBM guarantees a minimum level
                  of PDL Rebates each year of this Agreement. The guaranteed
                  level of PDL Rebate per PDL branded prescription claim for
                  Health Plan business shall be as follows: First, the total
                  number of Health Plan prescription claims for 1999 will be
                  multiplied by *. Second, the resulting sum will be divided by
                  the number of Health Plan PDL branded prescription claims for
                  the same period. Third, an additional * per claim will be
                  added to the resulting per PDL branded prescription claim
                  rebate level. This will be the PDL Rebate Guarantee level for
                  the year 2000. Each calendar year thereafter, the PDL Rebate
                  level will be increased by *. This is the "Adjusted Level" of
                  the PDL Rebate Guarantee. After each full contract year
                  beginning on the Commencement Date, PBM shall calculate the
                  total PDL Rebates applicable to PDL branded prescription
                  claims dispensed for United HealthCare's Health Plan business
                  during such contract year. If such PDL Rebates for any
                  contract year are less than (a) the Adjusted Level of PDL
                  Rebate per PDL branded prescription claim multiplied by (b)
                  the total number of PDL branded prescription claims paid for
                  Health Plan business during the contract year, then PBM shall
                  pay such difference ("Guaranteed PDL Rebates") to United
                  HealthCare. *

                  5.5.2. Good Faith Rebate Negotiations and Distribution. *

                  5.5.3. Customer ERISA Requirements. As part of the standard
                  Administrative Fee, PBM agrees to provide a report to United
                  HealthCare, which discloses ERISA required information about
                  rebates for United HealthCare customers. PBM agrees to assist
                  United HealthCare as reasonably requested in providing
                  disclosure information to each of its self-insured customers.
                  PBM acknowledges that as required by ERISA, United
                  HealthCare's self-insured customers retain the right to
                  terminate use of the PDL if customer does not agree with a PDL
                  selection.

                  5.5.4. Drug Formulary Only Administration. PBM shall, at
                  United HealthCare's request, provide drug formulary only
                  rebate administration for no additional fee for pharmacy
                  claims processed by other entities, if such business qualifies
                  for PDL Rebates. Such entities shall comply with PBM's data
                  format requirements and processes. The PDL Rebate Guarantee
                  shall not apply to Drug Formulary Only accounts.

                  5.5.5. Government and Other Actions. In the event any
                  government action, including a change in statute or regulation
                  or a change in the interpretation of statute or regulation
                  that has a material adverse affect on the availability of PDL


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.


                                       15

<PAGE>



                  Rebates, parties shall negotiate in good faith to modify the
                  Guaranteed PDL Rebate terms to reflect the effect of such
                  event.

         5.6. Conversion Costs and Services. It is the intent of this Agreement
         that PBM shall provide the majority of services required to convert
         United HealthCare's present pharmacy benefit management service from
         its current vendor to PBM. The parties agree that such costs for
         conversion services are included in the Administrative Fee. The
         conversion services provided by PBM shall include, but are not limited
         to: (a) communications to Covered Persons, physicians, pharmacies; (b)
         group training of United HealthCare pharmacy, sales and other staff;
         (c) development of Covered Person materials; (d) required modification
         of PBM's information systems; (e) development of the Minnesota
         Dedicated Pharmacy Management Unit; (f) analytical support for the
         conversion of models and tools for rebates, networks and guarantees;
         and (g) printing of physician and Covered Person PDLs. United
         HealthCare's only responsibility for conversion costs and services is
         limited to postage, pharmacy management implementation leadership,
         internal United HealthCare communications, limited internal United
         HealthCare information system programming, state filings, and servicing
         of customer calls coming directly into United HealthCare. The parties
         agree that if the conversion to PBM services results in unanticipated
         problems, the parties shall commit such additional resources, as
         mutually agreed, in order to implement this program in accordance with
         the terms of this Agreement.

SECTION 6. CONFIDENTIALITY

         6.1. Confidential and Proprietary Information. In fulfilling the
         objectives of this Agreement, United HealthCare and PBM may provide to
         each other or learn (directly or indirectly) certain information which
         a party considers to be confidential or proprietary ("Confidential
         Information"). Confidential Information shall include, without
         limitation, information relating to Covered Person and provider
         identities; reimbursement procedures; claims adjudication procedures;
         software and financial systems; the specific financial sections and
         provisions, specific operational aspects, financial guarantees
         contained in this Agreement, and other information relating to each
         party's business which is not generally available to the public. Each
         party's Confidential Information shall also include confidential,
         proprietary information which a third party has disclosed to a party,
         and which such party is obligated to maintain as confidential.
         Notwithstanding the foregoing, PBM and United HealthCare acknowledge
         the other party's obligation to provide its pharmaceutical
         manufacturers and customers with information generally regarding this
         Agreement and consistent with the foregoing agrees that such parties
         may disclose generally the terms of this Agreement.

                  6.1.1. Neither party shall have any obligation to disclose its
                  Confidential Information to the other party, unless such an
                  obligation is set forth elsewhere in this Agreement.

                  6.1.2. Each party agrees to maintain the secrecy of and not to
                  use or disclose the other party's Confidential Information,
                  except as required in order for a party to perform under this
                  Agreement. A party may disclose the other party's Confidential
                  Information only to the receiving party's directors, officer,
                  employees, agents and representatives (collectively, the
                  "Representatives"), but only if a Representative needs to know
                  the Confidential Information in order for



                                       16

<PAGE>



                  the receiving party to perform under this Agreement. The
                  parties agree to inform their Representatives of the
                  confidential nature of the disclosing party's Confidential
                  Information, and each party shall require any Representative,
                  who is not an employee of the receiving party to sign an
                  appropriate confidentiality agreement to protect the
                  disclosing party's Confidential Information from unauthorized
                  use or disclosure. Each party shall direct its Representatives
                  to treat the other party's Confidential Information
                  confidentially, and not to use it, other than to perform under
                  this Agreement. Each party shall be responsible for its
                  Representatives' use and disclosure of the other party's
                  Confidential Information.

                  6.1.3. The restrictions in this Section 6.1 shall not apply
                  to: (a) information which is or becomes generally available to
                  the public, other than as a result of a disclosure by the
                  receiving party; (b) information a party obtains from a third
                  party which has no obligation to keep the information
                  confidential; (c) information which a party had in its
                  possession prior to receiving Confidential Information from
                  the disclosing party; (d) information which is independently
                  developed by a party without reference to the Confidential
                  Information disclosed by the other party; or (e) information
                  required to be disclosed by law, subject to compliance with
                  Section 6.1.4.

                  6.1.4. The parties agree that if a party is required (by
                  subpoena, civil investigative demand or similar process) to
                  disclose the other party's Confidential Information, the
                  disclosing party shall notify the other party of the request
                  or requirement so that the other party may seek an appropriate
                  protective order or waive compliance with the sections or
                  provisions of this Agreement. The parties agree to exercise
                  their commercially reasonable efforts to assist each other in
                  obtaining a protective order or other reliable assurance that
                  confidential treatment will be accorded the Confidential
                  Information.

                  6.1.5. Upon termination of this Agreement each party will
                  immediately discontinue use of the other party's Confidential
                  Information, and shall return the other party's Confidential
                  Information to it, or destroy the other party's Confidential
                  Information in its possession or control. However, each party
                  may retain the other party's Confidential Information to the
                  extent such Confidential Information has been used in or
                  integrated into reports, studies, analyses, compilations or
                  other documents in the receiving party's possession or
                  control. Any oral Information will continue to be subject to
                  the terms of this letter agreement. The parties agree that the
                  Confidentiality obligations of this Section 6 shall survive
                  termination of this Agreement.

         6.2. Privacy of Individually Identifiable Health Information. United
         HealthCare and PBM will maintain the privacy and confidentiality of all
         individually identifiable information regarding Covered Persons and
         non-Covered Persons in accordance with all applicable statutes and
         regulations. PBM and United HealthCare shall require all employees to
         comply with this section. PBM agrees that all Covered Person
         information provided to PBM by United HealthCare belongs exclusively to
         United HealthCare.

         6.3. United HealthCare's Database. Subject to Section 6.4 below, PBM
         agrees that all data of United HealthCare and its affiliates, including
         but not limited to Covered Person, customer, and provider related data,
         which is in PBM's possession, whether



                                       17

<PAGE>


         obtained by PBM in the course of providing services for United
         HealthCare or as a result of a data transfer between United HealthCare
         and PBM, belongs solely to United HealthCare. PBM has the right to
         possess and use such data only to the extent permitted by contracts
         between the parties or as otherwise provided in this Agreement subject
         to applicable legal restrictions. All information contained in United
         HealthCare's database and systems belongs exclusively to United
         HealthCare. PBM shall not have direct access to United HealthCare's
         database and systems without signing a separate agreement with United
         HealthCare. PBM and United HealthCare recognize and agree that only
         information necessary for PBM performance under the Agreement shall be
         supplied by United HealthCare to PBM and PBM agrees that such data
         belongs exclusively to United HealthCare.

         6.4 PBM Use of Data. Notwithstanding the foregoing provisions of this
         Section 6, PBM may incorporate prescription data into PBM's
         prescription database when that database is used by PBM or provided to
         others for research, statistical, marketing, sales tracking or similar
         purposes. PBM agrees that if such prescription data is identifiable as
         to (a) Covered Persons, (b) employers and/or customers, and/or (d)
         United HealthCare, such identifiable information will be deleted or
         encrypted before it is provided to others. This section only applies to
         PBM's use of prescription data and does not apply to medical data.

SECTION 7. INTELLECTUAL PROPERTY

         7.1. Any Intellectual Property developed solely by PBM without using
         United HealthCare's Confidential Information shall remain the property
         of PBM. United HealthCare's right to use such PBM Intellectual Property
         shall be limited to those permitted by this Agreement or as otherwise
         agreed to in writing by the parties.

         7.2. Any Intellectual Property developed solely by United HealthCare,
         without utilizing PBM's Confidential Information shall remain the
         property of United HealthCare. PBM's right to use such Intellectual
         Property shall be limited to those permitted by this Agreement or as
         otherwise agreed to in writing by the parties.

         7.3. The parties agree that any Intellectual Property or work product:
         (a) created jointly by the parties; or (b) created by PBM under this
         Agreement; or (c) created by PBM upon United HealthCare's request (the
         "Work Product"), shall be the joint property of PBM and United
         HealthCare.

SECTION 8. YEAR 2000 WARRANTY

PBM and United HealthCare warrant that (a) the goods and services to be provided
under this Agreement are in a state of Year 2000 Compliance, (b) the delivery of
the goods or services provided under this Agreement to parties will not be
adversely affected by Year 2000 Compliance (including without limitation the
Year 2000 Compliance of parties' information and/or operating systems or those
of any third parties that assist parties in the fulfillment of its obligations
under this Agreement); (c) the goods or services provided under this Agreement
to the parties will not affect or impair the Year 2000 Compliance of the parties
or any third party that has a business relationship with parties; and (d) The
parties have taken all necessary or appropriate steps to insure that it is in
compliance with the foregoing warranties. "Year 2000


                                       18

<PAGE>



Compliance" means the ability of information or other systems to: (x) record,
store, process, provide, and insert true and accurate dates and calculations for
dates including and following January 1, 2000; and (y) process records
containing dates after January 1, 2000; and (z) be interoperable in such
respects with other systems used by the parties PBM, the PBM's parties' vendors
of any kind, or the parties , including without limitation those which may
deliver records to, receive records from or otherwise interact with the goods or
services provided by the parties.

SECTION 9. EXCLUSIVITY

         9.1 Except as defined in Section 9 and its subparts, United HealthCare
         Services, Inc. agrees that it shall not enter into a contract, or any
         other similar arrangement, for pharmacy benefit management services
         with a third party other than PBM with respect to services beginning
         with the Commencement Date and continuing until the term of this
         Agreement expires or until the Agreement is terminated.

         9.2 This exclusivity section does not apply to any entities who: (a)
         are acquired by or merged with United HealthCare Services, Inc. and its
         affiliates and subsidiaries after this Agreement is executed; and (b)
         have a contractual relationship with another pharmacy benefit
         management company, at the time this Agreement is executed. The parties
         agree that in no event will United HealthCare be required to terminate
         another pharmacy benefit management vendor prior to the expiration of
         such vendor's contract. United HealthCare agrees to convert any such
         entity to coverage under this Agreement as soon as said entity's
         contract with such other pharmacy benefit manager expires or can be
         reasonably terminated without the payment of any additional fees,
         fines, penalties, or damages. United HealthCare shall use its
         reasonable commercial efforts to include such entities under this
         Agreement. Within sixty (60) days after execution of this Agreement,
         United HealthCare shall provide PBM with the name of any such entity
         that has a contractual relationship in effect with another pharmacy
         benefit manager, the termination date of said contract and the
         approximate number of persons covered under such contract.

         9.3 Notwithstanding the foregoing, United HealthCare shall not be
         required to include government-defined benefit programs or any entity
         for which United HealthCare provides management or administrative
         services but does not own a controlling interest unless such entity
         agrees to utilize the services contemplated by this Agreement.

         9.4 The parties acknowledge and agree that United HealthCare may not be
         able to transition all Covered Persons and participating Health Plans
         to PBM: (a) on the Commencement Date; and/or (b) immediately in the
         event of an acquisition, merger or similar transaction that occurs
         prior to or during the term of this Agreement. The parties agree that a
         reasonable transition of Covered Persons and participating Health Plans
         related to (a) and (b) of this section shall not be considered a breach
         of this Section 9 or of this Agreement. Notwithstanding the foregoing,
         United HealthCare shall transition all existing Health Plans that will
         be covered under this Agreement within a six (6) month period of the
         Commencement Date unless otherwise mutually agreed to by the parties.
         This is not meant to restrict United HealthCare's ability to add other
         Health Plans and non-Health Plans during the term of this Agreement.

SECTION 10. RENEGOTIATION DUE TO SUBSTANTIAL CHANGE



                                       19

<PAGE>


In the event of a Substantial Change the parties agree to renegotiate in good
faith so as to reflect as nearly as possible the economic factors that were the
basis for this Agreement prior to the Substantial Change. In the event such
renegotiations do not result in a mutually agreeable economic solution or the
parties are not able to agree as to whether a Substantial Change has occurred,
such issue shall be submitted pursuant to the dispute resolution procedure set
forth in Section 13. 6.

SECTION 11. INDEMNIFICATION

         11.1. United HealthCare agrees to indemnify and hold PBM, its
         subsidiaries and affiliates, and their respective officers, directors,
         agents and employees harmless from and against any and all liabilities,
         losses, proceedings, actions, damages, claims or expenses of any kind,
         including reasonable attorneys' fees, which result from (a) a breach by
         United HealthCare of any of its obligations under this Agreement or (b)
         the negligence or willful acts or omissions by United HealthCare, its
         agents, directors, officers, or employees, in connection with the
         representations, duties and obligations of United HealthCare under this
         Agreement.

         11.2. PBM agrees to indemnify and hold United HealthCare, its
         subsidiaries and affiliates, and their respective officers, directors,
         agents and employees harmless from and against any and all liabilities,
         losses, proceedings, actions, damages, claims or expenses of any kind,
         including reasonable attorneys' fees, which result from (a) a breach by
         PBM of any of its obligations under this Agreement or (b) the
         negligence or willful acts or omissions by PBM, its agents, directors,
         officers, or employees, in connection with the representations, duties
         and obligations of PBM under this Agreement.

SECTION 12. TERM AND TERMINATION

         12.1. Term. The term of this Agreement is for the period commencing on
         the Effective Date and ending December 31, 2005, with performance
         beginning on the Commencement Date, unless terminated earlier as
         outlined in Section 12.2.

         12.2. Termination. This Agreement may be terminated as follows:

                  12.2.1. By either party, after a ten day notice period, in the
                  event of a payment default, unless such default is cured
                  within such notice period, unless the defaulting party is able
                  to give assurances to the other party's reasonable
                  satisfaction.

                  12.2.2. By either party, effective 30 days after not less than
                  60 days written notice and cure period in the event of a
                  material breach other than a payment default of this Agreement
                  by the other party.

                  12.2.3. By either party, effective immediately upon provision
                  of written notice to the other party, if the other party has
                  become insolvent or has been dissolved or liquidated, or makes
                  a general assignment for the benefit of creditors or has a
                  receiver appointed for a substantial portion of its assets.



                                       20

<PAGE>


                  12.2.4. Automatically and without any notice or other action
                  on the part of either party if either party files, or has
                  filed against it, a petition in bankruptcy and such petition
                  is not dismissed within 60 days of the filing unless the party
                  which is not subject to such petition elects to waive such
                  termination prior to the expiration of such 60 day period.

                  12.2.5. By either party immediately due to loss of insurance
                  or inability to self-insure as required under this Agreement.

                  12.2.6. By United HealthCare, effective at a time reasonable
                  to transferring the pharmacy management services to a new
                  vendor but no later than 180 days after notice to PBM, if a
                  change of control of PBM occurs. For purposes of this Section,
                  "Change of Control" means: (a) any transaction or series of
                  transactions that cause 50% or more of the stock of PBM or
                  United HealthCare, as the case may be, to be held by
                  individuals or entities who are not stockholders of PBM or
                  United HealthCare, as the case may be, on the date hereof; or
                  (b) any sale of PBM assets or United HealthCare, as the case
                  may be, that are essential to the business of PBM or United
                  HealthCare, as the case may be; or (c) any merger where PBM or
                  United HealthCare, as the case may be, is not the surviving
                  entity.

         12.3. United HealthCare Change of Control. If during the term of the
         Agreement, there is a Change of Control of United HealthCare, as
         defined above, United HealthCare has the option to terminate the
         Agreement by providing PBM with ninety (90) days prior written notice
         and by paying to PBM within sixty days of termination date an amount
         equal to the aggregate payments that have been made to United
         HealthCare by PBM under Trend Guarantee and PDL Rebate Guarantee as
         addressed in the Financial Appendix. If any such termination occurs
         prior to payment by PBM of any Trend Guarantee or PDL Rebate Guarantee,
         United HealthCare shall pay to PBM within 60 days after such
         termination date an amount equal to the transition costs paid by PBM to
         United HealthCare pursuant to Provision 8 of the Financial Appendix.

         12.4. Information to Covered Persons. PBM acknowledges the right of
         United HealthCare to inform Covered Persons of PBM's termination.

         12.5. End of Term or Termination. In the event this Agreement is
         terminated for any reason prior to its expiration or upon the end of
         the term, PBM and United HealthCare shall cooperate reasonably with
         each other for up to a six month period following such termination or
         expiration to effect a quality, cost-effective and smooth transition of
         United HealthCare's business previously operated or managed by PBM to
         United HealthCare or United HealthCare's designee. At the end of the
         term, United HealthCare has the following options: (a) re-negotiate the
         Agreement with PBM; (b) contract with a new pharmacy benefit management
         vendor; or (c). *.

                  12.5.1. Renegotiate the Agreement with PBM. Parties agree to
                  begin negotiating a new agreement at a time mutually agreed to
                  by the parties.

---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.


                                       21

<PAGE>


                  12.5.2. Contract with a new pharmacy benefit management
                  vendor. If United HealthCare chooses the option of contracting
                  with a new pharmacy benefit management vendor or chooses to
                  manage its own pharmacy services, the parties agree to the
                  following:

                           12.5.2.1     *

                           12.5.2.2.    *

                           12.5.2.3.    *

                           12.5.2.4.    *

12.5.3.  *.

SECTION 13. GENERAL PROVISIONS

         13.1. Notices. All notices or other communications required or
         permitted hereunder shall be in writing and shall be delivered
         personally, by commercial overnight delivery service, by facsimile or
         sent by certified, registered or express air mail, postage prepaid, and
         shall be deemed given when so delivered personally, by overnight
         delivery service or by facsimile, or if mailed, five days after the
         date of mailing, addressed as follows:

<TABLE>
<CAPTION>
        ------------------------------------------------------- ---------------------------------------------------
        If to PBM:                                              If to United HealthCare:
        ------------------------------------------------------- ---------------------------------------------------
        <S>                                                     <C>
        Merck Medco Managed Care, L.L.C.                        United HealthCare Services, Inc.
        100 Summit Avenue                                       9900 Bren Road East, P.O. Box 1459
        Montvale, New Jersey  07645-1753                        Minnetonka, Minnesota 55343
        Attention: Jim Cooper, Esq.                             Attention:  David Lubben, Esq.
        General Counsel                                         General Counsel
        Facsimile No. (201) 782-7878                            Facsimile No. (612) 936-0044
        ------------------------------------------------------- ---------------------------------------------------
</TABLE>


         or to such other address or to such other person as may be designated
         by written notice given from time to time during the term of the
         Agreement by one party to the other.

         13.2. Right of First Offer. Subject to such confidentiality
         arrangements as PBM may reasonably propose, PBM agrees to provide
         United HealthCare with reasonable prior notice of any event that might
         lead to a change of control of PBM (which shall include any sale of
         more than 10% of the voting securities to an entity not wholly owned by
         Parent. Any notice herein contemplated shall be given to the Chief
         Executive Officer or General Counsel of United HealthCare. Such advance
         notification shall be maintained strictly confidential to the Chief
         Executive Officer and General Counsel, except with the written consent
         of the person giving notification.

         13.3. Force Majeure. Noncompliance with the obligations of this
         Agreement due to force majeure, laws or regulations of any government,
         war, civil commotion, destruction of production facilities and
         materials, fire, earthquake or storm, labor disturbances, shortage of
         materials, failure of public utilities or common carriers, and any
         other causes beyond the reasonable control of the applicable party,
         shall not constitute breach of contract.

----------
*    Represents text deleted pursuant to a confidentiality treatment claim
     filed with the Securities and Exchange Commission pursuant to Rule 406
     under the Securities Act of 1933, as amended.

                                       22

<PAGE>


         13.4. Assignment. United HealthCare may assign all or any of its rights
         and responsibilities under this Agreement to any entity controlling,
         controlled by or under common control with United HealthCare. United
         HealthCare may make such an assignment that is effective only after the
         party to which such rights or responsibilities are assigned (the
         "Assignee") no longer controls, is controlled by or is under common
         control of such party; provided, however, that any such entity is
         reasonably able to perform any responsibilities which it assumes.
         United HealthCare may assign its rights and responsibilities in such a
         way that both United HealthCare and Assignee share in the rights and
         responsibilities that, prior to such assignment, were solely those of
         United HealthCare. PBM may assign all or any of its rights and
         responsibilities under this Agreement to any entity controlling,
         controlled by, or under common control with such party. PBM and United
         HealthCare each acknowledge that persons and entities under contract
         with such party or in the case of United HealthCare, a Participating
         Plan, may perform certain administrative services under this Agreement.
         Other than above, United HealthCare and PBM agree that they shall not
         assign any of the rights and responsibilities under this Agreement
         without the prior written consent of the other party.

         13.5. Amendment. Any amendments to this Agreement shall require written
         approval of the parties.

         13.6. Dispute Resolution. Any controversy or claim arising out of or
         relating to this Agreement or a breach of the Agreement shall initially
         be submitted to the Strategic Council for resolution. The Strategic
         Council shall have the authority to: (a) waive the controversy, claim
         or breach; (b) designate specific corrective or alternative action; (c)
         set a time period for certain performance; (d) submit the matter to
         mediation; or (e) allow a party to litigate the issue. Any action taken
         by the Strategic Council shall be evidenced by a written notice to both
         parties. During the period of time in which such issues are being
         examined by the Strategic Council or are under mediation or litigation,
         the parties shall proceed diligently with the performance of their
         duties under this Agreement in a businesslike and efficient manner. In
         the event the Strategic Council cannot resolve the matter within sixty
         days or the matter is not one which must be submitted to the Strategic
         Council, then within a reasonable time, a party or the Strategic
         Council may submit the matter to mediation or litigation in
         Minneapolis, Minnesota.

         13.7. Relationship Between United HealthCare and PBM. The relationship
         between United HealthCare and PBM is solely that of independent
         contractors and nothing in this Agreement or otherwise will be
         construed or deemed to create any other relationship, including one of
         employment, agency or joint venture.

         13.8. Invalidity/Governing Law. If any section or provision of this
         Agreement is finally declared or found to be illegal or unenforceable
         by a court of competent jurisdiction, both parties shall be relieved of
         all obligations arising under such section or provision, but if capable
         of performance, the remainder of this Agreement shall not be affected
         by such declaration or finding.

         13.9. Accreditation Compliance. PBM agrees to provide United HealthCare
         with reasonable assistance and cooperation in meeting all accreditation
         standards, including but not limited to National Committee for Quality
         Assurance and Joint Commission, applicable to the services provided
         pursuant to this Agreement.



                                       23

<PAGE>


         13.10. Name, Symbol and Service Mark. During the term of this
         Agreement, PBM and United HealthCare agree that they shall not use each
         other's name, symbol or logo, or service mark for any purpose
         whatsoever including without limitation in connection with marketing or
         publications describing, explaining, or otherwise discussing the
         Program without the prior approval of the other party.

         13.11. Headings. The headings of the various sections herein are for
         convenience of reference only and shall not define, limit or otherwise
         affect any of the terms or sections or provisions hereof.

         13.12. Original Agreement. The parties agree that they shall execute
         two identical originals of this Agreement. Each party shall retain one
         of the originals. Each identical original shall serve as an original of
         the Agreement but all such originals together shall constitute a single
         original contract.

         13.13. Governing Law. This Agreement shall be governed by and construed
         in accordance with applicable Minnesota law without giving effect to
         conflict of law principle.

         13.14. Entire Agreement. This Agreement and its Financial Appendix,
         Exhibits A and B, and Attachments 1 and 2 constitute the entire
         Agreement between the parties in regard to its subject matter.

         13.15. Regulatory Approval. The parties agree and acknowledge that the
         terms of this Agreement may be subject to review by state regulators.

         13.16. Approvals. Approvals required under this agreement shall not be
         unreasonably delayed or withheld.

         13.17. Additional Agreements. Upon request, PBM agrees to enter into an
         additional separate agreement with any United HealthCare affiliate
         receiving services hereunder reflecting the services received and
         obligations of such affiliate.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first set forth above.

UNITED HEALTHCARE SERVICES, INC.                MERCK MEDCO MANAGED CARE, L.L.C.
9900 Bren Road East                             100 Summit Avenue
Minnetonka, Minnesota  55343                    Montvale, New Jersey  07645-1753

By:/s/ Steve Hemsley                            By:/s/ James Cooper
   -------------------------                       ----------------

Date: November 11, 1998                         Date: November 10, 1998
      -----------------                               -------------------


                                       24

<PAGE>




                               FINANCIAL APPENDIX

1. Retail Pharmacies: Charges for Dispensed Covered Prescription Drug Services

United HealthCare will pay PBM for Covered Prescription Drug Services under the
Retail Pharmacy Program per the processing logic and rates indicated below:

*

<TABLE>
<CAPTION>
------------------------------------- ----------------------------------- -----------------------------------
              Network                            AWP Discount                       Dispensing Fee
------------------------------------- ----------------------------------- -----------------------------------
<S>                                   <C>                                 <C>
                                      *                                   *
------------------------------------- ----------------------------------- -----------------------------------
CCNIII                                *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Brand                             *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Generic                           *                                   *
------------------------------------- ----------------------------------- -----------------------------------
                                      *                                   *
------------------------------------- ----------------------------------- -----------------------------------
CCN+                                  *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Brand                             *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Generic                           *                                   *
------------------------------------- ----------------------------------- -----------------------------------
                                      *                                   *
------------------------------------- ----------------------------------- -----------------------------------
United HealthCare Custom              *                                   *
------------------------------------- ----------------------------------- -----------------------------------
  Urban                               *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Brand                             *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Generic                           *                                   *
------------------------------------- ----------------------------------- -----------------------------------
  Rural                               *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Brand                             *                                   *
------------------------------------- ----------------------------------- -----------------------------------
    Generic                           *                                   *
------------------------------------- ----------------------------------- -----------------------------------
                                      *                                   *
------------------------------------- ----------------------------------- -----------------------------------
</TABLE>

Key: Rural pharmacies are those independent pharmacies that are the only
pharmacy in the rural pharmacy's zip code. Urban pharmacies refer to all other
pharmacies.

Note 1:  Measured against all generic products
Note 2.  Measured against MAC listed drugs only




---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.


                                       25

<PAGE>



2.       Mail Service:  Charges for Covered Prescription Drug Services

A.       United HealthCare will pay PBM for Covered Prescription Drug Services
         under the Mail Service Pharmacy Program an amount equal to a * discount
         off AWP for generic drugs and a * discount off AWP for brand drugs
         minus Covered Person's Copayment. No dispensing fees or other fees will
         be charged for Mail Service prescriptions.

B.       Within sixty (60) days following the end of each Trend Period, PBM will
         calculate and report to United HealthCare the number of prescriptions
         that PBM has dispensed to Covered Persons in such Trend Period under
         the Mail Service Program. If the number is greater than * PBM will pay
         United HealthCare * in immediately available funds within ten (10)
         business days of receiving such report. If the number is greater than *
         PBM will pay United HealthCare * in immediately available funds within
         ten (10) business days of receiving such report. PBM will pay United
         HealthCare an additional * for every * such dispensed prescriptions in
         excess of *. Payments for mail service claim volume of * or more will
         be represented by the following formula:

         Bonus = *

3.       Base Administrative Fee

United HealthCare shall pay PBM an Base Administrative Fee of * per prescription
for retail and mail services. This fee is for a retail card program and includes
out of network paper claims and encompasses the services described in Exhibit A
to this Agreement, and Sections 3 and 5 of this Agreement. This Base
Administrative Fee shall remain fixed for the duration of the contract term,
unless reduced pursuant to Provision 7 of this Financial Appendix.

4.       Additional Administrative Fees

United HealthCare shall pay PBM for additional administrative services United
HealthCare utilizes as follows:

  -----------------------------------------------------------------------------
  Service                                            Additional Fee
  -----------------------------------------------------------------------------
                                                     *
  -----------------------------------------------------------------------------
  Optional explanation of benefits (EOB)             *
  -----------------------------------------------------------------------------
  Annual prescription benefit record (PBR)           *
  -----------------------------------------------------------------------------
  Managed prior authorization Level I                *
  -----------------------------------------------------------------------------
  Managed prior authorization Level II               *
  -----------------------------------------------------------------------------
  Physician profiling                                *
  -----------------------------------------------------------------------------
  ID Card                                            *
  -----------------------------------------------------------------------------
  Paid Direct                                        *
  -----------------------------------------------------------------------------
                                                     *
  -----------------------------------------------------------------------------



---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.


                                       26

<PAGE>



5.       *

6.       Drug Utilization Review (DUR) Savings Guarantee

United HealthCare Health Plans and non-Health Plans may choose to participate in
PBM's Drug Utilization Review ("DUR") Savings Guarantee during the term of this
Agreement. PBM's DUR programs consist of Concurrent DUR, Managed Rx,
Retrospective DUR and Electronic POS Edits designed to promote cost effective,
medically appropriate prescription drug therapy.

         A.       Non-Health Plans. During the term of this Agreement, PBM will
                  calculate and report to United HealthCare (the "DUR Report"),
                  within ninety (90) days after the end of each full calendar
                  year during the term of this Agreement, the total savings to
                  United HealthCare resulting from participation in the DUR
                  Program for United HealthCare's non-Health Plan business
                  segments that participate in the DUR Program, and which (i)
                  participate in the PDL, and (ii) cooperate with PBM's DUR
                  protocols, ("Qualifying Plans"), for such contract year ("DUR
                  Savings"). DUR Savings will be reported, and the DUR Savings
                  Guarantee will apply, on an individual stand alone basis for
                  Qualifying Plans consisting of * or more Covered Persons. DUR
                  Savings will be reported, and the DUR Savings Guarantee will
                  apply, on an aggregate basis for Qualifying Plans consisting
                  of less than * Covered Persons, and shall be deemed a single
                  Qualifying Plan.

                  (1)      PBM guarantees that the DUR Savings for Qualifying
                           Plans each full contract year during the term of this
                           Agreement will equal or exceed the applicable
                           percentage of * for all Qualifying Plans for such
                           Contract Year ("Guaranteed DUR Savings"), as set
                           forth below:

                                                     Guaranteed DUR Savings*
                             Contract Year           (as % of Net Plan Costs)
                             -------------           ------------------------
                             1st Contract Year       *
                             2nd Contract Year       *
                             3rd Contract Year       *
                             4th Contract Year       *
                             5th Contract Year       *

                             * Contingent upon PBM's review of Qualifying Plan
                               data

                  (2)      For the amount, if any, in any contract year that the
                           DUR Savings for any Qualifying Plan(s) are less than
                           the Guaranteed DUR Savings, PBM will pay such
                           difference to United HealthCare on a
                           dollar-for-dollar basis. For example, if DUR Savings
                           for a Qualifying Plan for the 1st contract year are *
                           PBM shall pay United HealthCare an amount equal to *
                           of the * for such Qualifying Plan for such contract
                           year.

                  (3)      For the amount, if any, in any contract year that the
                           DUR Savings for any Qualifying Plan(s) exceed the
                           Guaranteed DUR Savings, United HealthCare shall pay
                           PBM an amount equal to * of the dollar amount of


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



                                       27

<PAGE>

                           such excess. For example, if DUR Savings for a
                           Qualifying Plan for the 1st contract year are *
                           United HealthCare shall pay PBM an amount equal to *
                           of * for such Qualifying Plan for such contract year.

                  (4)      Any payment required by PBM under this Provision 6
                           shall be made within * days after provision of the
                           applicable DUR Report to United HealthCare. Any
                           payment required by United HealthCare pursuant to
                           this Provision 6 shall, at United HealthCare's
                           option, either (a) be paid within * days of United
                           HealthCare's receipt of the applicable DUR Report, or
                           (b) be retained by PBM from PDL Rebates payable to
                           United HealthCare pursuant of Section 5.5 and its
                           subparts of this Agreement.

7.       *
8.       Transition Costs

To cover costs incurred by United HealthCare in transitioning its Covered
Persons from its current vendor to PBM, PBM shall pay United HealthCare as
follows:

*

9.       *



---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



                                       28

<PAGE>




                                    Exhibit A

                 PBM INTEGRATED RETAIL AND MAIL PROGRAM SERVICES

The services listed below will be performed exclusively by PBM for United
HealthCare's Health Plan business. United HealthCare shall make best efforts to
utilize PBM services for its non-Health Plan business. United HealthCare can
request the discontinuation of any service listed below and/or may perform any
services listed below internally at United HealthCare but may not contract with
another organization to perform these services. From time to time PBM
acknowledges that it will modify the services on this Agreement or add new
services to be more effective. Such modified or new services will be provided to
United HealthCare.

1.   Claims Processing

     o    Electronic Processing in Network
     o    Paper Claims Processing in-network and out-of-network
     o    Mail Service Dispensing and Adjudication
     o    In-network claims adjudication via TelePAIDsm on-line claims
          adjudication system
     o    Coordination of Benefits Administration Level I & II when flagged on
          eligibility records
     o    Concurrent Drug Utilization Review (DUR) via TelePAIDsm
     o    Managed Rx (for Health Plan, and also for non-Health Plan businesses
          that choose to participate in the DUR Guarantee
     o    High Utilization Management program (Identification Module)
     o    Retrospective Drug Utilization Review (DUR)
     o    Pharmacy Payment Processing (edits/quality management)
     o    Twelve month on-line claims history retention
     o    Monitor Participating Pharmacy compliance including submission of
          usual and customer, generic dispensing rates, PDL conformance, DUR
          intervention, conformance, patient utilization and drug mix
     o    On-line viewing access to claims history

2.   Eligibility Management

     o    Administration of eligibility submitted by multiple sources per tape
          or electronically with variable United HealthCare formats with
          reasonable notice of changes to such formats
     o    Dependent Eligibility Certification System (DECS)
     o    PBM's client support system (CAS) for on-line access to eligibility,
          claims history for add/deletes/changes o Toll-free access to PBM's
          help desk for eligibility/claims processing assistance
     o    Administration of paper adds/deletes/changes
     o    24 hour eligibility/claims processing support



                                       29

<PAGE>



3.   Benefits Management

     o    Customized Program Installation Materials
     o    Administration of benefits submitted electronically or by tape or by
          paper
     o    Administration of paper adds/deletes/changes
     o    Administration of benefit designs that include single or tiered
          copayments, coinsurance or deductible, maximum limits, out-of-pocket
          limits.
     o    Managed Prior Authorization Level I and II (programs, installation and
          administration) for Health Plans

4.   Reporting: Aggregate and Individual Payor Reporting
     (for groups in excess of * Covered Persons)

     o    Production Reporting/Paper Reports/Ad hoc reports
     o    PBM's Standard PLUS Report Series
     o    Claim history tape following each check write
     o    EXPERxT/TM/ - PBM's enhanced Claims Analysis Product for in-depth
          analysis and ad-hoc reporting including on-line analytic reports/tools

5.   Pharmacy Network Management

     o    Establish, credential, contract, and maintain Participating Provider
          networks for United HealthCare
     o    Develop and distribute communications to Participating Providers
          following review by United HealthCare
     o    Audit Participating Provider Network and Program by retrospective
          review and on-site review using the PBM's Pharmacy Audit Program

6.       Call Center Services

     o    24 hour, seven day a week live customer service (or less if mutually
          agreed)
     o    Toll-free telephone access to Customer Service for the Program for use
          by Covered Persons, benefits personnel, pharmacists and physicians
     o    Toll-free access to pharmacists for DUR assistance
     o    Toll-free telephone access to voice response unit for location of
          network Participating Pharmacies in zip code areas
     o    24 hour access to a pharmacist via toll-free telephone service for
          Covered Persons
     o    TDD-TTY services for hearing impaired
     o    Telephonic/fax-back PDL (physician) o Telecommunications support for
          800 numbers (up to * lines)
     o    Clinical program support for the 800 numbers

7.   Support Staff


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



                                       30

<PAGE>



     o    Pharmacy Management Support Teams (clinical/sales/operations/services)
          for United HealthCare
     o    Pharmacy Network Management
     o    Manufacturer Rebate Contracts
     o    Customer Service including Covered Person/pharmacy support and
          clinical program support at an 800 number
     o    Corporate Consulting Support for

          (a)  P&T Committee
          (b)  Benefit design analysis
          (c)  Pipeline analysis
          (d)  Manufacturer relations
          (e)  Communications/marketing support
          (f)  Legal support
          (g)  Underwriting support

8.   Account Management

     o    Clinical and Program consulting, analysis and cost projections
     o    Annual review and analysis of:

          (a)  Program
          (b)  Utilization
          (c)  Plan design and impact of design
          (d)  Recommendations; interventions

9.   Utilization: PBM will optimize generic utilization through the following
     PBM Programs:

     o    Physician DAW interventions via fax and telephone
     o    PBM proprietary MAC pricing
     o    Impact of PBM's performance retail network including provider
          relations review, pharmacy audit program and special pharmacy
          incentives and messaging to drive generic substitution
     o    "Mandatory generic" or "patient pays the difference" plan design
     o    Brand name to generic retail patient education mailings
     o    Brand name to generic mail service patient education inserts o Mail
          service auto substitution

10.  Other Services
     o    Participant materials
     o    Printing/distribution of PDLs
     o    Mailing of payments - direct Covered Person reimbursement under a
          retail card program



                                       31

<PAGE>

                                    EXHIBIT B

                  SERVICE PERFORMANCE STANDARDS AND GUARANTEES

PBM is committed to providing the highest level of service in the industry and
will guarantee essential services to assure professional, responsive service to
United HealthCare and its Covered Persons. PBM recognizes the challenges
associated with changing pharmacy benefit management services vendors and has
supplemented these service performance guarantees with an implementation
guarantee to demonstrate PBM's commitment towards making the transition smooth
and trouble free. PBM guarantees the following performance specifically for the
United HealthCare Program:

         1.       Audits

                  PBM will guarantee that * of retail pharmacies will be audited
                  on site each calendar year. PBM will be assessed a penalty of
                  * of Base Administrative Fees paid by United HealthCare during
                  such calendar year if this target is not met.

         2.       System Availability

                  PBM will guarantee a * systems availability (other than
                  scheduled maintenance times) during normal service hours each
                  calendar year. PBM will be assessed a penalty of * of Base
                  Administrative Fees paid by United HealthCare during such
                  calendar year if this target is not met.

         3.       Eligibility

                  PBM will guarantee that * of processable maintenance
                  eligibility transactions received by PBM via host to host,
                  tape or floppy disk on any business day by 2 p.m. EST will be
                  processed within one business day each calendar year. PBM will
                  be assessed a penalty of * of Base Administrative Fees paid by
                  United HealthCare during such calendar year if this target is
                  not met.

         4.       Accuracy of Prescriptions

                  PBM will guarantee an overall mail service pharmacy accuracy
                  rating of * based upon collected and tracked external feedback
                  from individuals receiving prescriptions from such mail
                  service pharmacy each calendar year. PBM will be assessed a
                  penalty of * of Base Administrative Fees paid by United
                  HealthCare during such calendar year if this target is not
                  met.


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



                                       32

<PAGE>


         5.       Correspondence

                  PBM will guarantee that * of Covered Person correspondence
                  will be finalized and responded to within * business days
                  after receipt by PBM and * of Covered Person correspondence
                  will be responded to within * business days after receipt by
                  PBM each calendar year. PBM will be assessed a penalty of * of
                  Base Administrative Fees paid by United HealthCare during such
                  calendar year if this target is not met.

         6.       Telephone Response

                  PBM will guarantee that Covered Person service representatives
                  will answer * of incoming telephone calls within * from the
                  initial ring each calendar year. PBM will be assessed a
                  penalty of * of Base Administrative Fees paid by United
                  HealthCare during such calendar year if this target is not
                  met.

         7.       Telephone Abandonment Rate

                  PBM will guarantee a customer call abandonment rate of * or
                  less each calendar year. PBM will be assessed a penalty of *
                  of Base Administrative Fees paid by United HealthCare during
                  such calendar year if this target is not met.

         8.       Paper Claims

                  PBM will guarantee that * of Covered Person submitted claims
                  will be responded to within * business days, and * of Covered
                  Person submitted claims will be responded to within * business
                  days each calendar year. Response means either a check or
                  reject notice has been mailed. PBM will be assessed a penalty
                  of * of Base Administrative Fees paid by United HealthCare
                  during such calendar year if this target is not met.

        Qualification: Total aggregate Service Performance Guarantees in any
                       contract year will not exceed * of the total Base
                       Administrative Fee.



---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.


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<PAGE>



                                  ATTACHMENT 1

                                    GUARANTY

     In consideration for United HealthCare Services, Inc. ("United HealthCare")
entering into the Pharmacy Benefit Management Agreement with Merck Medco Managed
Care, L.L.C., located at 100 Summit Avenue, Montvale, New Jersey 07645-1753
("PBM") dated November 11, 1998 (the "Agreement"), Merck & Co., Inc., a Delaware
corporation and holder of a 100% ownership interest in PBM ("Merck") hereby
guarantees the prompt and complete performance by said PBM of all of PBM's
obligations under the Agreement, including without limitation, performance of
all services, and payment of all sums payable thereunder, including but not
limited to the Rebate Guarantee, Trend Guarantee and Price Guarantee. This
Guaranty is made by Merck pursuant to Section 3.22 of the Agreement, and is
irrevocable as long as there are obligations of PBM remaining under the
Agreement.

     This is a continuing, absolute, primary and unconditional guaranty of
performance and payment and not of collection. Merck specifically waives any
right to subrogation, setoff or counterclaim, and any defense for changes in
applicable law or any other circumstances that might constitute a legal or
equitable defense or discharge of a guarantor or surety. Merck waives any right
to require a proceeding first against PBM or to exhaust any security for the
performance of the obligations of PBM, and waives notice of acceptance hereof
and of defaults hereunder.

     Merck agrees that its liability shall not be affected or decreased by any
amendment, termination, extension, renewal, waiver or modification of the
Agreement or the rejection or disaffirmance thereof in bankruptcy or like
proceedings. This Guaranty shall be binding upon Merck, its legal
representatives, and assigns, and shall inure to United HealthCare's benefit and
to the benefit of its successors and assigns. This Guaranty shall be governed by
and construed in accordance with applicable Minnesota law without giving effect
to conflict of law principle.

     Merck represents that the officer signing on its behalf has been duly
authorized to execute this Guaranty for and on behalf of Merck by its Board of
Directors.


Dated:                                     Merck & Co., Inc.



                                           By:

[Corporate Seal]                           Title:




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<PAGE>





                                  ATTACHMENT 2

*


---------------
* Represents text deleted pursuant to a confidentiality treatment claim filed
with the Securities and Exchange Commission pursuant to Rule 406 under the
Securities Act of 1933, as amended.



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