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                                                                   EXHIBIT 10.97

                                                                  EXECUTION COPY

                 ASSUMPTION REINSURANCE AND MARKETING AGREEMENT

      This Assumption Reinsurance and Marketing Agreement (this "Agreement"),
dated October 8, 2004, is among The Chesapeake Life Insurance Company
("CHESAPEAKE"), an Oklahoma domiciled health and life insurance corporation and
an indirect wholly owned subsidiary of UICI; HealthMarket Inc., a Delaware
corporation ("HMI"); and American Travelers Assurance Company ("ATAC"), a
District of Columbia domiciled health and life insurance company and a wholly
owned subsidiary of HMI. This Agreement shall be effective as of the Effective
Date (as such term is hereinafter defined).

      WHEREAS, The MEGA Life and Health Insurance Company ("MEGA") (a wholly
owned subsidiary of UICI and the direct parent of CHESAPEAKE), HMI and a wholly
owned subsidiary of HMI have entered into an Asset Purchase Agreement, dated as
of September 3, 2004 (the "Asset Purchase Agreement"), pursuant to which MEGA
has agreed, subject to the terms and conditions thereof, to purchase certain of
the operating assets of HMI, subject to certain liabilities, all as more
particularly described therein;

      WHEREAS, the Asset Purchase Agreement does not contemplate the purchase by
MEGA of any interest in the capital stock of ATAC;

      WHEREAS, pursuant to the terms of a Services Agreement (the "Services
Agreement"), dated as of April 30, 2002, as amended as of December 31, 2003, HMI
currently provides administrative and other services to ATAC;

      WHEREAS, pursuant to the terms of the Asset Purchase Agreement, HMI will
assign all of its right, title and interest in and to, and MEGA will agree to
assume HMI's obligations under, such Services Agreement;

      WHEREAS, subject to the terms and conditions hereof, ATAC desires to cede,
and CHESAPEAKE desires to reinsure on an assumption basis, 100% of the liability
associated with the ATAC Assumed Policies (as such term is hereinafter set
forth);

      WHEREAS, UICI, MEGA, CHESAPEAKE and HMI believe that, following the
assumption reinsurance of the ATAC Assumed Policies as herein contemplated, it
would be in the best interests of ATAC policyholders to enroll in a policy
underwritten by CHESAPEAKE after the close of the transaction contemplated by
the Asset Purchase Agreement, because CHESAPEAKE's A.M Best rating of "A-" and
its strong capital position can provide increased security to current customers
of ATAC; and

      WHEREAS, UICI, MEGA, CHESAPEAKE and HMI further believe that enabling
existing ATAC customers to receive substantially similar benefits and coverage
as provided by their existing in-force policies, including accumulated benefits
in their Health Reimbursement Accounts, will be in the best interest of ATAC
policyholders.

      NOW THEREFORE, for and in consideration of the mutual agreements and
covenants herein contained, the receipt and sufficiency of which is hereby
acknowledged, the parties hereto agree as follows:

      1.    Definitions. As used in this Agreement, the following capitalized
terms shall have the respective meanings hereafter set forth:

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      "Affiliate" of any Person shall mean and include any Person who controls,
is controlled by or is under common control with such Person.

      "ATAC Assumed Policies" shall mean all the policies and certificates of
group health insurance with respect to groups of 75 or fewer subscribers
directly issued by ATAC as a result of applications written by or on behalf of
ATAC, as more particularly set forth in Exhibit A attached hereto and made a
part hereof.

      "CHESAPEAKE Issued Policy" shall mean a policy or certificate of group
health insurance with respect to groups of 75 or fewer subscribers directly
issued by CHESAPEAKE in replacement or upon conversion of ATAC Assumed Policies
in accordance with Section 8 hereof.

      "Computation Period" shall have the meaning assigned to it in Section 8.3
hereof.

      "Effective Date" shall mean the later of (a) November 1, 2004, or (b) such
date as the parties shall have received applicable regulatory approvals for the
transactions contemplated hereby (including without limitation written
confirmation from the Texas Department of Insurance that, following the
transaction contemplated hereby, neither CHESAPEAKE nor the ATAC Assumed
Policies will be subject to the Texas reinsurance pool).

      "Incurred Claims" shall mean with respect to the ATAC Assumed Policies
claims paid for services rendered on or after the Effective Date plus any and
all outstanding claim liabilities (reserves) associated with such claims.

      "Membership Med-Loss Ratio" shall mean, with respect to ATAC Assumed
Policies and calculated with respect to the Computation Period, the ratio of (a)
medical benefits incurred during the Computation Period (including medical
claims, prescription drug claims and care management fees paid) to (b) earned
premium for the Computation Period.

      "Person" shall mean an individual, a corporation, partnership, limited
liability company, trust, unincorporated association or any other legal entity.

      2.    Cession and Transfer by ATAC. As of the Effective Date:

            2.1. ATAC agrees to transfer, assign, cede, deliver and convey to
      CHESAPEAKE all of the rights, privileges and prerogatives of ATAC in and
      to the ATAC Assumed Policies.

            2.2. ATAC agrees to cooperate with CHESAPEAKE with respect to the
      transfer of any records relating to or pertinent to the ATAC Assumed
      Policies that may be in the possession of ATAC.

            2.3. ATAC further agrees to use it best efforts to ensure that any
      reinsurance (other than the Texas voluntary reinsurance pool) that is in
      force with respect to the ATAC Assumed Policies on the Effective Date
      shall continue in force in accordance with its terms and be assigned to
      CHESAPEAKE.

            2.4. ATAC agrees to and does hereby assign and transfer to
      CHESAPEAKE all liability owing to agents for commissions that become due
      on or after the Effective Date as to the ATAC Assumed Policies.

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      3.    Assumption of Obligations by CHESAPEAKE. As of the Effective Date,
CHESAPEAKE agrees to fully reinsure and assume all of the rights and liabilities
of ATAC (including but not limited to the liability for agents' commissions)
under and or relating to the ATAC Assumed Policies and reinsurance agreements or
treaties related thereto, incurred on or after the Effective Date, subject in
each and every case to any and all defenses or offsets against claims and
actions under such ATAC Assumed Policies that would have been available to ATAC
had the parties not entered into this Agreement.

      4.    Premium Payment and Transfer of Funds.

            4.1. On and after the Effective Date, CHESAPEAKE shall be entitled
      to collect, retain and invest an amount equal to 100% of the premiums
      collected on the ATAC Assumed Policies less premiums refunded and
      commissions paid; provided, however, that CHESAPEAKE shall reimburse
      and/or hold ATAC harmless from and with respect to premium taxes or other
      taxes or assessments levied against or with respect to such premiums.

            4.2. CHESAPEAKE shall fund and maintain proper reserves against the
      liabilities relating to the ATAC Assumed Policies for obligations incurred
      on or after the Effective Date in accordance with applicable statutory
      requirements. CHESAPEAKE's assets constituting statutory reserves may be
      invested as permitted by applicable statutes and regulations. CHESAPEAKE
      shall be entitled to all income from any and all sources derived from
      premiums paid with respect to the ATAC Assumed Policies.

            4.3. ATAC shall fund and maintain proper reserves against the
      liabilities relating to the ATAC Assumed Policies for obligations incurred
      before the Effective Date in accordance with applicable statutory
      requirements. ATAC's assets constituting statutory reserves may be
      invested as permitted by applicable statutes and regulations.

      5. Notice to Policyholders and Administration. CHESAPEAKE agrees that it
will issue and mail a Certificate of Assumption or a Notice of Transfer (each
substantially in the forms attached hereto as Exhibit B and Exhibit C,
respectively) as soon as is practicable after the Effective Date to each owner
of an ATAC Assumed Policy at the owner's address last shown on the books and
records of ATAC. As provided in the Services Agreement, MEGA (as assignee of
HMI's rights and obligations under the Services Agreement) shall continue to
collect premiums due and otherwise continue to administer the business with
respect to coverage afforded under such ATAC Assumed Policies.

      6. Regulatory Approvals. It is understood and agreed that any required
submission and approval of this Agreement or the transactions contemplated
hereby to any applicable regulatory agency shall be the joint responsibility of
CHESAPEAKE and HMI. CHESAPEAKE and HMI will cooperate in this process and be
available for consultations, as necessary, with the applicable regulatory
agencies. Without limiting the generality of the foregoing, ATAC shall undertake
and be responsible for any and all regulatory compliance actions that may be
required in connection with such approval.

      7. Other Rights and Duties.

            7.1. On and after the Effective Date, CHESAPEAKE through its duly
      authorized representatives shall have the right to obtain and retain all
      records, books and data of ATAC relating to the ATAC Assumed Policies
      (including such records, books and data that may be essential to the
      proper administration of the business covered by this Agreement), to
      administer the business assumed hereunder, and to take any and all such
      other action as it shall deem necessary to effect the proper transfer of
      the administration of the ATAC Assumed Policies to

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CHESAPEAKE in accordance with the terms of this Agreement and the Services
Agreement. CHESAPEAKE shall, whenever reasonably requested by ATAC, permit ATAC
to have access to such records, books and data turned over to CHESAPEAKE
pursuant to this Agreement as may be required by ATAC in connection with any
audit or investigation by any governmental authority, or any matter relating to
insurance coverage or third party claims. CHESAPEAKE shall preserve and maintain
such records, books and data for at least three (3) years after the Effective
Date or such longer period as shall be required under applicable law and
regulations.

      7.2. On and after the Effective Date, ATAC agrees to cooperate with
CHESAPEAKE in the transfer of the administration of such business to CHESAPEAKE.

8.    Conversion of ATAC Assumed Policies.

      8.1. On and after the Effective Date and otherwise in accordance with and
subject to the terms of this Section 8, CHESAPEAKE shall market to and solicit,
at an appropriate premium rate, insureds under each and every ATAC Assumed
Policy in an effort to convert such ATAC Assumed Policy to a CHESAPEAKE Issued
Policy on such date as and when such ATAC Assumed Policy is, in accordance with
its terms, subject to renewal.

      8.2. Subject to adjustment as hereinafter set forth, CHESAPEAKE agrees to
pay to HMI a fee (the "Replacement Fee") in an amount equal to 15% of annualized
premium associated with each CHESAPEAKE Issued Policy, such fee to be paid in
cash on the last day of the calendar month immediately following the month
during which CHESAPEAKE first receives premium with respect to such CHESAPEAKE
Issued Policy.

      8.3. As hereinafter provided, the Replacement Fee payable by CHESAPEAKE
with respect to a CHESAPEAKE Issued Policy will be adjusted upward or downward
based on the cumulative performance of the corresponding ATAC Assumed Policy
during the period commencing on the Effective Date and ending on the date of
issue of such CHESAPEAKE Issued Policy (the "Computation Period").

            8.3.1. The Replacement Fee payable with respect to a CHESAPEAKE
      Issued Policy shall be adjusted on a dollar-for-dollar basis downward in
      an amount equal to the positive difference (if any) between (a) the actual
      Incurred Claims with respect to the corresponding ATAC Assumed Policy
      during the Computation Period and (b) the Incurred Claims that would have
      been paid with respect to such ATAC Assumed Policy during the Computation
      Period assuming the Membership Med-Loss Ratio during the Computation
      Period was 78.0%; or

            8.3.2. The Replacement Fee payable with respect to a CHESAPEAKE
      Issued Policy shall be adjusted on a dollar-for-dollar basis upward in an
      amount equal to the positive difference (if any) between (a) the Incurred
      Claims that would have been paid with respect to the corresponding ATAC
      Assumed Policy assuming the Membership Med-Loss Ratio during the
      Computation Period was 77.0% and (b) the actual Incurred Claims with
      respect to such ATAC Assumed Policy during the Computation Period; or

            8.3.3. There shall be no adjustment to the Replacement Fee if the
      terms of neither Sections 8.3.1 nor 8.3.2 shall be applicable.

      8.4. The calculation of the aggregate adjustments to the Replacement Fee
with respect to all CHESAPEAKE Issued Policies shall occur on a quarterly basis,
with a final "true up" to

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occur six months after the date of replacement of the last block of ATAC Assumed
Policies that result in the issue of the CHESAPEAKE Issued Policies. In
addition, CHESAPEAKE shall have the right to offset against any amounts due HMI
hereunder (whether or not such amounts are liquidated or reduced to judgment)
the amount of any moneys due it pursuant to the terms of the Asset Purchase
Agreement (including without limitation any amounts due MEGA upon the making of
any claim for indemnification under Section 12 thereof).

      8.5. CHESAPEAKE agrees to utilize actuarially acceptable reserving
standards for determining claim liability under each ATAC Assumed Policy. Each
of CHESAPEAKE and ATAC shall have the right to appoint an independent actuarial
firm to review and assess CHESAPEAKE's reserving methodology and determination
of claim liability with respect to the ATAC Assumed Policies during the
Computation Period.

9.    Representations and Warranties.

      9.1. Representations and Warranties of ATAC. ATAC represents and warrants
to CHESAPEAKE as follows:

            9.1.1. ATAC is a corporation duly organized, validly existing and in
      good standing under the laws of the District of Columbia, and has full
      power and authority to own, lease and operate its properties and assets
      and to conduct its business as presently conducted (except that ATAC is
      subject to a number of regulatory orders affecting its certificate of
      authority in certain states or ability to issue new and/or renewal
      policies, including without limitation, a Corrective Action Order issued
      by the District of Columbia Department of Insurance restricting ATAC from
      issuing new policies until ATAC receives additional capital), and to enter
      into this Agreement and to carry out the transactions contemplated by this
      Agreement.

            9.1.2. The execution, delivery and performance by ATAC of this
      Agreement have been duly authorized by all necessary corporate action, and
      this Agreement has been duly executed and delivered by ATAC. This
      Agreement constitutes the valid and binding obligation of ATAC, legally
      enforceable against ATAC in accordance with its terms, except as such
      enforcement may be limited by bankruptcy, receivership, insolvency or
      other similar laws affecting the enforcement of creditors' rights
      generally and except that the availability of equitable remedies is
      subject to the discretion of the court before which any proceeding
      therefor may be brought.

            9.1.3. The execution of and performance by ATAC of its obligations
      under this Agreement will not violate any provision of law or governmental
      rule or regulation, and will not conflict with or result in any breach of
      any of the terms, conditions or provisions of, or constitute a default
      under (i) ATAC's Certificate of Incorporation, (ii) ATAC's by laws as
      currently in effect, (iii) any judgment, decree or order to which ATAC is
      bound or (iv) any agreement, contract, lease, indenture or other
      instrument to which ATAC is bound.

      9.2. Representations and Warranties of CHESAPEAKE. CHESAPEAKE represents
and warrant to ATAC as follows:

            9.2.1. CHESAPEAKE is a corporation duly organized, validly existing
      and in good standing under the laws of the State of Oklahoma and has full
      power and authority to own, lease and operate its properties and assets
      and to conduct its business as presently

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      conducted, and to enter into this Agreement and to carry out the
      transactions contemplated by this Agreement.

            9.2.2. The execution, delivery and performance by CHESAPEAKE of this
      Agreement have been duly authorized by all necessary corporate action, and
      this Agreement has been duly executed and delivered by CHESAPEAKE. This
      Agreement constitutes the valid and binding obligation of CHESAPEAKE,
      legally enforceable against CHESAPEAKE in accordance with its terms,
      except as such enforcement may be limited by bankruptcy, receivership,
      insolvency or other similar laws affecting the enforcement of creditors'
      rights generally and except that the availability of equitable remedies is
      subject to the discretion of the court before which any proceeding
      therefor may be brought.

            9.2.3. The execution of and performance by CHESAPEAKE of its
      obligations under this Agreement will not violate any provision of law or
      governmental rule or regulation, and will not conflict with or result in
      any breach of any of the terms, conditions or provisions of, or constitute
      a default under (i) CHESAPEAKE's Certificate of Incorporation, (ii)
      CHESAPEAKE's by-laws as currently in effect, (iii) any judgment, decree or
      order to which CHESAPEAKE is bound or (iv) any agreement, contract, lease,
      indenture or other instrument to which CHESAPEAKE is bound.

      9.3. Representations and Warranties of HMI. HMI represents and warrant to
CHESAPEAKE as follows:

            9.3.1. HMI is a corporation duly organized, validly existing and in
      good standing under the laws of the State of Delaware and has full power
      and authority to own, lease and operate its properties and assets and to
      conduct its business as presently conducted, and to enter into this
      Agreement and to carry out the transactions contemplated by this
      Agreement.

            9.3.2. The execution, delivery and performance by HMI of this
      Agreement have been duly authorized by all necessary corporate action, and
      this Agreement has been duly executed and delivered by HMI. This Agreement
      constitutes the valid and binding obligation of HMI, legally enforceable
      against HMI in accordance with its terms, except as such enforcement may
      be limited by bankruptcy, receivership, insolvency or other similar laws
      affecting the enforcement of creditors' rights generally and except that
      the availability of equitable remedies is subject to the discretion of the
      court before which any proceeding therefor may be brought.

            9.3.3. The execution of and performance by HMI of its obligations
      under this Agreement will not violate any provision of law or governmental
      rule or regulation, and will not conflict with or result in any breach of
      any of the terms, conditions or provisions of, or constitute a default
      under (i) HMI's Certificate of Incorporation, (ii) HMI's by-laws as
      currently in effect, (iii) any judgment, decree or order to which HMI is
      bound or (iv) any agreement, contract, lease, indenture or other
      instrument to which HMI is bound.

10.   Indemnification.

      10.1. Indemnification by CHESAPEAKE. CHESAPEAKE agrees to indemnify and
hold harmless each of HMI and ATAC and HMI's and ATAC's directors, officers,
successors, agents, employees, partners, representatives, heirs, assigns,
affiliates and subsidiaries harmless

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from and against any and all losses, damages (excluding punitive and
consequential damages), liabilities, regulatory fines, penalties, costs and
expenses (including, without limitation, attorneys' fees, investigation costs
and all other reasonable costs associated with the defense thereof)
(collectively, "Losses"), as incurred, arising out of or relating to (a) all of
the rights and liabilities of ATAC under the ATAC Assumed Policies incurred on
or after the Effective Date (including without limitation claims for insurance
benefits thereunder, liability for agents' commissions thereunder, and any other
liabilities and undertakings assumed by CHESAPEAKE hereunder with respect
thereto); (b) breach of any of the other covenants or agreements to be performed
by CHESAPEAKE hereunder; and (c) breaches of any representation or warranty made
by CHESAPEAKE hereunder.

      10.2. Indemnification by ATAC and HMI. Each of HMI and ATAC agrees to
indemnify and hold harmless CHESAPEAKE and CHESAPEAKE's directors, officers,
successors, agents, employees, partners, representatives, heirs, assigns,
affiliates and subsidiaries harmless from and against any and all Losses, as
incurred, arising out of or relating to (a) all of the rights and liabilities of
ATAC under the ATAC Assumed Policies incurred prior to the Effective Date
(including without limitation claims for insurance benefits thereunder,
liability for agents' commissions thereunder); (b) breach of any of the
respective covenants or agreements to be performed by ATAC and HMI hereunder;
and (c) breaches of any representation or warranty made by HMI or ATAC hereunder

      10.3. Conduct of Indemnification Proceedings.

            10.3.1. If any proceeding shall be brought or asserted against any
      person entitled to indemnification hereunder (an "Indemnified Party"),
      such Indemnified Party promptly shall notify the person from whom
      indemnity is sought (the "Indemnifying Party") in writing, and the
      Indemnifying Party shall assume the defense thereof, including the
      employment of counsel reasonably satisfactory to the Indemnified Party and
      the payment of all fees and expenses incurred in connection with defense
      thereof; provided, however, that the failure of any Indemnified Party to
      give such notice shall not relieve the Indemnifying Party of its
      obligations or liabilities pursuant to this Agreement, except (and only)
      to the extent that it shall be finally determined by a court of competent
      jurisdiction (which determination is not subject to appeal or further
      review) that such failure shall have proximately and materially adversely
      prejudiced the Indemnifying Party.

            10.3.2. An Indemnified Party shall have the right to employ separate
      counsel in any such proceeding and to participate in the defense thereof,
      but the fees and expenses of such counsel shall be at the expense of such
      Indemnified Party or Parties unless: (1) the Indemnifying Party has agreed
      in writing to pay such fees and expenses; or (2) the Indemnifying Party
      shall have failed promptly to assume the defense of such Proceeding and to
      employ counsel reasonably satisfactory to such Indemnified Party in any
      such Proceeding; or (3) the named parties to any such proceeding
      (including any impleaded parties) include both such Indemnified Party and
      the Indemnifying Party, and such Indemnified Party shall have been advised
      by counsel that a conflict of interest is likely to exist if the same
      counsel were to represent such Indemnified Party and the Indemnifying
      Party (in which case, if such Indemnified Party notifies the Indemnifying
      Party in writing that it elects to employ separate counsel at the expense
      of the Indemnifying Party, the Indemnifying Party shall not have the right
      to assume the defense thereof and such counsel shall be at the reasonable
      expense of the Indemnifying Party). The Indemnifying Party shall not be
      liable for any settlement of any such proceeding effected without its

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      written consent, which consent shall not be unreasonably withheld. No
      Indemnifying Party shall, without the prior written consent of the
      Indemnified Party, effect any settlement of any pending proceeding in
      respect of which any Indemnified Party is a party, unless such settlement
      includes an unconditional release of such Indemnified Party from all
      liability on claims that are the subject matter of such proceeding,

            10.3.3. All fees and expenses of the Indemnified Party (including
      reasonable fees and expenses to the extent incurred in connection with
      investigating or preparing to defend such proceeding in a manner not
      inconsistent with this Section) shall be paid to the Indemnified Party, as
      incurred, within ten (10) business days of a detailed written notice
      thereof to the Indemnifying Party (regardless of whether it is ultimately
      determined that an Indemnified Party is not entitled to indemnification
      hereunder; provided, that the Indemnifying Party may require such
      Indemnified Party to undertake to reimburse all such fees and expenses to
      the extent it is finally judicially determined that such Indemnified Party
      is not entitled to indemnification hereunder).

      11.   Confidentiality. Each of the parties hereto agrees that the terms of
this Agreement, the negotiations leading to this Agreement, and this Agreement
shall be treated as strictly confidential, and that no such party shall
disclose, disseminate, or publicize, or cause or permit to be disclosed,
disseminated, or publicized the terms of this Agreement, the negotiations
leading to this Agreement or the Agreement to any Person; provided, however,
nothing hereunder shall be deemed to prevent or restrict disclosure of such
information by a party (a) confidentially to such party's legal counsel and tax
advisors under such circumstances where such persons have a need to know; (b) to
the extent necessary to report income to appropriate taxing authorities; (c) to
an applicable state department of insurance or other regulatory authority having
jurisdiction over such party; and (d) in response to an order or subpoena of a
court or governmental agency of competent jurisdiction, provided in such case
that notice of receipt of any such order or subpoena shall be immediately
communicated to the other parties hereto so that they may have an opportunity to
intervene and assert their rights with respect to non-disclosure prior to such
party's response to such order or subpoena. Notwithstanding the foregoing, the
confidentiality obligations of this Section shall not apply to information (i)
which either party is compelled to disclose by judicial or administrative
process, or, in the opinion of counsel, by other mandatory requirements of law;
(ii) which can be shown to have been generally available to the public other
than as a result of a breach of this Section; or (iii) which can be shown to
have been provided to either party by a third party who obtained such
information other than from the other party or other than as a result of a
breach of this Section.

      12. Dispute Resolution.

            12.1. If any party to this Agreement has any claim, right or cause
      of action against any other party to this Agreement, which the parties
      shall be unable to settle by agreement between themselves, such claim,
      right or cause of action, to the extent that the relief sought by such
      party is for monetary damages or awards, shall be determined by
      arbitration in accordance with the provisions of this Section 12 and the
      Commercial Arbitration Rules of the American Arbitration Association.

            12.2. The party or parties requesting arbitration shall serve upon
      the other or others a demand therefor, in writing, specifying the matter
      to be submitted to arbitration, and nominating a competent disinterested
      person (who shall be a then current or former officer of a life insurance
      company or reinsurance company) to act as an arbitrator. Within twenty
      (20) days after receipt of such written demand and nomination, the other
      party or parties shall, in writing, nominate a competent disinterested
      person, and the two (2) arbitrators so designated shall, within twenty
      (20)

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      days thereafter, select a third arbitrator. The three (3) arbitrators
      shall give immediate written notice of such selection to the parties and
      shall fix in said notice a time and place of the meeting of the
      arbitrators which shall be as soon as conveniently possible (but in no
      event later than twenty days after the appointment of the third
      arbitrator), at which time and place the parties to the controversy shall
      appear and be heard with respect to the right, claim or cause of action.

            12.3. In case the notified party or parties shall fail to make a
      selection upon notice within the time period specified, the party
      asserting such claim shall appoint an arbitrator on behalf of the notified
      party. If the first two (2) arbitrators selected shall fail to agree upon
      a third arbitrator within twenty (20) days after their selection, then
      such arbitrator may, upon application made by either of the parties to the
      controversy, be appointed by any judge of any United States court of
      record having jurisdiction in the State of Texas.

            12.4. Each party shall present such testimony, examinations and
      investigations in accordance with such procedures and regulations as may
      be determined by the arbitrators and shall also recommend to the
      arbitrators a monetary award to be adopted by the arbitrators as the
      complete disposition of such claim, right or cause of action. After
      hearing the parties in regard to the matter in dispute, the arbitrators
      shall adopt as their determination with respect to such claim, right or
      cause of action, within twenty (20) days of the completion of the
      examination, by majority decision signed in writing (together with a brief
      written statement of the reasons for adopting such recommendation), one of
      the recommendations submitted by the parties to the dispute and shall
      grant no other relief or remedy. The decision of said arbitrators, absent
      fraud, duress or manifest error, shall be final and binding upon the
      parties to such controversy and may be enforced in any court of competent
      jurisdiction.

            12.5. The expense and cost of such arbitration shall be borne by the
      party or parties whose recommendation was not adopted by the arbitrators.
      Each party shall pay the fees and expenses of its own counsel.

            12.6. Notwithstanding any other provisions of this Section 12 if a
      party against whom any claim, right or cause of action is asserted
      commences, or has commenced against it, bankruptcy, insolvency or similar
      proceedings, the party or parties asserting such claim, right or cause of
      action shall have no obligations under this Section 12 and may assert such
      claim, right or cause of action in the manner and forum it deems
      appropriate, subject to applicable laws. No determination or decision by
      the arbitrators pursuant to this Section 12 shall limit or restrict the
      ability of any party hereto to obtain or seek in any appropriate forum,
      any relief or remedy that is not a monetary award or money damages.

      13.   General Matters.

            13.1. Any notice, request, instruction or other document to be given
      hereunder shall be in writing and: (a) delivered personally; (b) sent by
      registered or certified United States mail, postage prepaid, return
      receipt requested; (c) sent by Federal Express or other similarly
      reputable overnight courier; or (d) transmitted by facsimile, according to
      the instructions set forth below. Such notices shall be sent to the
      following addresses and/or facsimile numbers and shall be deemed given:
      (w) if delivered personally, at the time delivered; (x) if sent by
      registered or certified United States mail, at the time deposited in the
      United States mail; (y) if sent by Federal Express or other similarly
      reputable overnight courier, at the time sent, or (z) if transmitted by
      facsimile, at the time when receipt is confirmed by the sending facsimile
      machine.

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                         If to CHESAPEAKE, to:

                         The Chesapeake Life Insurance Company
                         9151 Grapevine Hwy
                         North Richland Hills, Texas 76180
                         Attention: William J. Gedwed, Chairman

                         With a copy to:

                         UICI
                         9151 Grapevine Hwy
                         North Richland Hills, Texas 76180
                         Attention: Glenn W. Reed, Executive Vice President and
                                     General Counsel

                         If to ATAC, to:

                         American Travelers Assurance Company
                         c/o HealthMarket Inc.
                         20 Glover Ave.
                         5th Floor
                         Norwalk, Connecticut 06850

                         If to HMI, to:

                         HealthMarket Inc,
                         20 Glover Ave.
                         5th Floor
                         Norwalk, Connecticut 06850

      or to such other address as such party may indicate by a notice delivered
      to the other parties hereto in accordance with the provisions of this
      Section 13.1.

            13.2. This Agreement contains the entire understanding of the
      parties hereto with regard to the subject matter contained herein or
      therein, and supersedes all prior written or oral agreements,
      understandings or letters of intent between or among any of the parties
      hereto. This Agreement shall not be amended, modified or supplemented
      except by a written instrument signed by an authorized representative of
      each of the parties hereto.

            13.3. The rights of each party under this Agreement shall not be
      assignable without the written consent of each of the other parties.

            13.4. This Agreement shall be binding upon and inure to the benefit
      of the parties hereto and their successors and permitted assigns. Nothing
      in this Agreement, expressed or implied, is intended or shall be construed
      to confer upon any Person other than the parties and successors and
      assigns permitted by this Section 13.4 any right, remedy or claim under or
      by reason of this Agreement.

            13.5. Headings to sections herein are inserted for convenience of
      reference only and are not intended to be part of or to affect the meaning
      or interpretation of this Agreement.

                                       10

<PAGE>

            13.6. This Agreement has been mutually prepared, negotiated and
      drafted by each of the parties hereto and thereto. The parties agree that
      the terms of this Agreement shall be construed and interpreted against
      each party in the same manner and that no such provisions shall be
      construed or interpreted more strictly against one party on the assumption
      that an instrument is to be construed more strictly against the party
      which drafted the agreement. Any term or provision of this Agreement may
      be waived, or the time for its performance may be extended, pursuant to a
      written action by the party or parties entitled to the benefit thereof.
      Any such waiver shall be validly and sufficiently authorized for purposes
      of this Agreement if, as to any party, it is authorized in writing by an
      authorized representative of such party. The failure of any party hereto
      to enforce at any time any provision of this Agreement shall not be
      construed to be a waiver of such provision, nor in any way to affect the
      validity of this Agreement or any part hereof or the right of any party
      thereafter to enforce each and every such provision. No waiver of any
      breach of this Agreement shall be held to constitute a waiver of any other
      or subsequent breach.

            13.7. Regardless of whether the transactions provided for in this
      Agreement are consummated, each party hereto will pay its own costs and
      expenses incident to the negotiation, preparation and performance of this
      Agreement, including the fees, expenses and disbursements of its counsel,
      financial advisors, and accountants.

            13.8. Wherever possible, each provision hereof shall be interpreted
      in such manner as to be effective and valid under applicable law, but in
      case any one or more of the provisions contained herein shall, for any
      reason, be held to be invalid, illegal or unenforceable in any respect,
      such provision shall be ineffective to the extent, but only to the extent,
      of such invalidity, illegality or unenforceability without invalidating
      the remainder of such invalid, illegal or unenforceable provision or
      provisions or any other provisions hereof, unless such a construction
      would be unreasonable.

            13.9. This Agreement may be executed in one or more counterparts,
      each of which shall be considered an original instrument, and shall become
      binding when one or more counterparts have been signed by each of the
      parties hereto and delivered to each of the parties hereto.

            13.10. This Agreement shall be governed by and construed in
      accordance with the internal laws of the State of Texas, without giving
      effect to any choice of laws provisions that may direct the application of
      the laws of another jurisdiction.

            13.11. Subject to the provisions of Section 12 hereof, each of the
      parties hereby: (a) agrees that any action arising out of or related to
      this Agreement or any of the transactions contemplated hereby or thereby
      shall be filed and shall proceed exclusively in the federal and state
      courts located in Dallas, Texas; (b) irrevocably consents to jurisdiction
      in such courts; and (c) waives any and all objections to jurisdiction and
      venue in such courts that they may have under the federal or state laws of
      the United States.

            13.12. The provisions of this Agreement are intended for the sole
      benefit of the parties hereto and shall not inure to the benefit of any
      other Person, other than successors and permitted assigns of parties
      hereto, whether as third party or otherwise.

                                     * * * *

                                       11

<PAGE>

      IN WITNESS WHEREOF, the undersigned have executed this Assumption
Reinsurance and Marketing Agreement on the date first above written.

                                      AMERICAN TRAVELERS ASSURANCE COMPANY

                                      By:______________________________________
                                      Name:____________________________________
                                      Its:_____________________________________

                                      HEALTHMARKET INC.

                                      By:______________________________________
                                      Name:____________________________________
                                      Its:_____________________________________

                                      THE CHESAPEAKE LIFE INSURANCE COMPANY

                                      By:______________________________________
                                      Name:____________________________________
                                      Its:_____________________________________

                                       12

<PAGE>



                                 AMENDMENT No. 1

                TO ASSUMPTION REINSURANCE AND MARKETING AGREEMENT

      This Amendment No, 1 to Assumption Reinsurance and Marketing Agreement
(this "Agreement"), dated March 1, 2005, is among The Chesapeake Life Insurance
Company ("CHESAPEAKE"), an Oklahoma domiciled health and life insurance
corporation and an indirect wholly owned subsidiary of UICI; HEI Exchange, Inc.
(formerly HealthMarket Inc.), a Delaware corporation ("HMI"); and American
Travelers Assurance Company ("ATAC"), a District of Columbia domiciled health
and life insurance company and a wholly owned subsidiary of HMI.

      WHEREAS, CHESAPEAKE, HMI and ATAC have entered into an Assumption
Reinsurance and Marketing Agreement, dated as of October 8, 2004 (the
"Agreement"), pursuant to which ATAC ceded, and CHESAPEAKE reinsured on an
assumption basis, 100% of the liability associated with certain ATAC Assumed
Policies (as such term is defined in the Agreement);

      WHEREAS, CHESAPEAKE, HMI and ATAC desire to amend the Agreement in
accordance with the terms hereof;

      NOW THEREFORE, for and in consideration of the mutual agreements and
covenants herein contained, the receipt and sufficiency of which is hereby
acknowledged, the parties hereto agree as follows:

      1. Definitions. Unless otherwise defined herein, all capitalized terms
used herein shall have the respective meanings assigned to them in the
Agreement.

      2. Amendments. Effective as of October 8, 2004, Sections 8.2, 8.3 and 8.4
of the Agreement are hereby deleted in their entirety and the following new
Sections 8.2, 8.3 and 8.4 shall be and are hereby inserted in lieu thereof:

            "8.2 CHESAPEAKE agrees to pay to HMI a fee (the "Replacement Fee")
      in an amount equal to 15% of annualized premium associated with each
      CHESAPEAKE Issued Policy, such Replacement Fee to be paid in cash on the
      last day of the calendar month immediately following the month during
      which CHESAPEAKE first receives premium with respect to such CHESAPEAKE
      Issued Policy.

            8.3 As hereinafter provided. CHESAPEAKE and HMI agree to make an
      adjustment to the Replacement Fee based on the cumulative profit/loss
      performance of each ATAC Assumed Policy during the period commencing on
      the Effective Date and ending on the date such ATAC Assumed Policy
      terminates (the "Computation Period").

                  8.3.1 HMI shall owe CHESAPEAKE (a "Loss Adjustment") with
            respect to an ATAC Assumed Policy if and to the extent that there is
            a positive difference between (a) the actual Incurred Claims with
            respect to such ATAC Assumed Policy during the Computation Period
            and (b) the Incurred Claims that would have been paid with respect
            to such ATAC Assumed Policy during the Computation Period assuming
            the Membership Med-Loss Ratio during the Computation Period was
            78.0%; or
<PAGE>
                  8.3.2. CHESAPEAKE shall owe HMI (a "Profit Adjustment") with
            respect to an ATAC Assumed Policy if and to the extent that there is
            a positive difference between (a) the Incurred Claims that would
            have been paid with respect to such ATAC Assumed Policy assuming the
            Membership Med-Loss Ratio during the Computation Period was 77.0%
            and (b) the actual Incurred Claims with respect to such ATAC Assumed
            Policy during the Computation Period; or

                  8.3.3 There shall be no Loss Adjustment or Profit Adjustment
            on any ATAC Assumed Policy if the terms of neither Sections 8.3.1
            nor 8.3.2 shall be applicable.

                  8.3.4. The calculation of the aggregate Profit Adjustments and
            Loss Adjustments on all ATAC Assumed Policies shall be made on a
            quarterly basis, and for purposes of payment hereunder Profit
            Adjustments and Loss Adjustments may be netted against each other
            and the resulting amount due to (from) CHESAPEAKE netted against
            (added to) the Replacement Fee payable from time to time by
            CHESAPEAKE to ATAC in accordance with the terms of Section 8.2
            above. A final "true up" shall occur with respect to the Profit
            Adjustment and Loss Adjustment applicable to ATAC Assumed Policies
            six months after the last ATAC Assumed Policy shall have lapsed or
            terminated.

            8.4. CHESAPEAKE shall have the right to offset against any amounts
      due HMI under this Agreement (whether or not such amounts are liquidated
      or reduced to judgment) the amount of any moneys due it pursuant to the
      terms of the Asset Purchase Agreement (including without limitation any
      amounts due MEGA upon the making of any claim for indemnification under
      Section 12 thereof)."

      3. General Matters.

            3.1. Except to the extent as herein amended or supplemented, the
      terms of the Agreement are confirmed in all respects and shall be and
      remain in full force and effect.

            3.2. This Amendment No. 1 contains the entire understanding of the
      parties hereto with regard to the subject matter contained herein or
      therein, and supersedes all prior written or oral agreements,
      understandings or letters of intent between or among any of the parties
      hereto. This Agreement shall not be amended, modified or supplemented
      except by a written instrument signed by an authorized representative of
      each of the parties hereto.

            3.3. Headings to sections herein are inserted for convenience of
      reference only and are not intended to be part of or to affect the meaning
      or interpretation of this Agreement.

                                      -2-
<PAGE>
            3.4. This Amendment No. 1 shall be governed by and construed in
      accordance with the internal laws of the State of Texas, without giving
      effect to any choice of laws provisions that may direct the application of
      the laws of another jurisdiction.

                                      ****

      IN WITNESS WHEREOF, the undersigned have executed this Amendment No. 1 to
Assumption Reinsurance and Marketing Agreement on the date first above written.

                                       AMERICAN TRAVELERS ASSURANCE COMPANY

                                       By: /s/ Stephen F. Wiggins
                                           -----------------------
                                       Name: Stephen F. Wiggins
                                       Its: President

                                       HEI EXCHANGE, INC.
                                       (formerly HealthMarket Inc.)

                                       By: /s/ Stephen F. Wiggins
                                           -----------------------
                                       Name: Stephen F. Wiggins
                                       Its: President

                                       THE CHESAPEAKE LIFE INSURANCE COMPANY

                                       By: /s/ Glenn W. Reed
                                           -----------------------
                                       Name: Glenn W. Reed
                                       Its: Vice President

                                      -3-