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                                                                   EXHIBIT 10.13

                 SECOND AMENDMENT TO THE 1996 STOCK OPTION PLAN
                         FOR OFFICERS AND KEY EMPLOYEES

     This Second Amendment dated June 12, 2003 (the "Amendment"), to the 1996
Stock Option Plan For Officers and Key Employees (the "Plan") of PacifiCare
Health Systems, Inc. hereby amends the Plan as follows:

     1. Amendment to Section 8.4.  Section 8.4 is hereby deleted and replaced in
its entirety by the following:

     Section  8.4 - Withholding Tax Liability.

     (a) To the extent provided by the terms of an Award, the Participant may
     satisfy any federal, state or local tax withholding obligation relating to
     the exercise, vesting, or acquisition of any Award by any of the following
     means (in addition to the Company's right to withhold from any compensation
     paid to the Participant by the Company) or by a combination of such means:
     (i) tendering a cash payment; (ii) authorizing the Company to withhold
     shares of Common Stock from the shares of Common Stock otherwise issuable
     to the Participant as a result of the exercise or acquisition of Common
     Stock under the Award or allow the return of shares of Common Stock upon
     the vesting of an Award, in each case having a Fair Market Value as of the
     date of withholding or repurchase equal to such tax obligation; or (iii)
     delivering to the Company owned and unencumbered shares of Common Stock
     having a Fair Market Value on the date of delivery equal to such tax
     obligation.

     (b) A share withholding election shall be deemed made when written notice
     of such election, signed by the holder of the Award, has been delivered or
     transmitted by registered or certified mail to the Secretary or Chief
     Financial Officer of the Company at its then principal office.  Delivery of
     said notice shall constitute an irrevocable election to have shares
     withheld.

     (c) Upon exercise of an Award by a holder, the Company shall transfer the
     total number of shares of Common Stock of the Company subject to the Award
     to the holder on the date of exercise, less any shares the holder elects to
     withhold.

     (d) If a Participant disposes of shares acquired pursuant to an Incentive
     Stock Option in any transaction considered a disqualifying transaction
     under Sections 421 and 422 of the Code, the Participant must give the
     Company written notice of transfer and the Company shall have the right to
     deduct any taxes required by law to be withheld from the amounts otherwise
     payable to the Participant.

     2. Limitation on Amendment.  This Amendment was approved by the Board in
accordance with Section 8.5 and does not require the approval of the
stockholders of the Company.  Except as expressly provided in this Amendment, no
terms or provisions of this Plan are modified or changed and the terms and
provisions of the Plan, as amended by this Amendment, shall continue in full
force and effect.

     3. Capitalized Terms.  Capitalized Terms not defined herein shall have the
meanings ascribed to them in the Plan.