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                                                                     EXHIBIT 4.4

                                   AETNA INC.
                          EMPLOYEE STOCK PURCHASE PLAN

1. PURPOSE OF THE PLAN. The purpose of the Plan is to provide employment
incentive through a capital accumulation opportunity, link employee and
shareholder interests, and provide an opportunity for employees of the Company
and its Participating Subsidiaries to purchase Common Stock through payroll
deductions.

2. DEFINITIONS.

      "BOARD" means the Company's Board of Directors.

      "CODE" means the Internal Revenue Code of 1986, as amended from time to
      time.

      "CHANGE-IN-CONTROL" means the happening of any of the following:

            (i) When any "person" as defined in Section 3(a)(9) of the
            Securities Exchange Act of 1934, as amended (the "Exchange Act"),
            and as used in Sections 13(d) and 14(d) thereof, including a "group"
            as defined in Section 13(d) of the Exchange Act but excluding the
            Company and any Subsidiary thereof and any employee benefit plan
            sponsored or maintained by the Company or any Subsidiary (including
            any trustee of such plan acting as trustee), directly or indirectly,
            becomes the "beneficial owner" (as defined in Rule 13d-3 under the
            Exchange Act, as amended from time to time), of securities of the
            Company representing 20 percent or more of the combined voting power
            of the Company's then outstanding securities;

            (ii) When, during any period of 24 consecutive months, the
            individuals who, at the beginning of such period, constitute the
            Board (the "Incumbent Directors") cease for any reason other than
            death to constitute at least a majority thereof, provided that a
            Director who was not a Director at the beginning of such 24-month
            period shall be deemed to have satisfied such 24-month requirement
            (and be an Incumbent Director) if such Director was elected by, or
            on the recommendation of or with the approval of, at least
            two-thirds of the Directors who then qualified as Incumbent
            Directors either actually (because they were Directors at the
            beginning of such 24-month period) or by prior operation of this
            paragraph (ii); or

            (iii) The occurrence of a transaction requiring shareholder approval
            for the acquisition of the Company by an entity other than the
            Company or a Subsidiary through purchase of assets, or by merger, or
            otherwise.

            Notwithstanding the foregoing, in no event shall a
            "Change-in-Control" be deemed to have occurred (i) as a result of
            the formation of a Holding Company, or (ii) with respect to any
            Employee, if such Employee is part of a "group", within the meaning
            of Section 13(d)(3) of the Exchange Act as in effect on the
            effective date, which consummates the Change-in-Control transaction.
            In addition, for purposes of the definition of "Change-in-Control" a
            person engaged in business as an underwriter of securities shall not
            be deemed to be the "beneficial owner" of, or to "beneficially own,"
            any securities acquired through such person's participation in good
            faith in a firm commitment underwriting until the expiration of
            forty days after the date of such acquisition.

      "COMMITTEE" means the Board's Committee on Compensation and Organization
      or such other committee of the Board designated by the Board to administer
      the Plan.

      "COMMON STOCK" means the common shares, $.01 par value of the Company.

      "COMPANY" means Aetna Inc., a Pennsylvania corporation.

      "COMPENSATION" means annual base salary during a Purchase Period and does
      not include any bonus, severance or overtime payment, disability payment,
      contributions to an employee benefit plan or other similar payment or
      contribution.

      "CONTINUOUS STATUS AS AN EMPLOYEE" means the absence of any interruption
      or termination of service as an Employee. Continuous Status as an Employee
      shall not be considered interrupted in the case of (i) sick leave, (ii)
      military leave, (iii) any other leave of absence approved by the Company,
      provided that such leave is for a period of not more than ninety (90)
      days, unless reemployment upon the expiration of such leave is guaranteed
      by contract or statute, or unless provided otherwise pursuant to Company
      policy adopted from time to time, or (iv) in the case of transfers between
      locations of the Company or between the Company and its Participating
      Subsidiaries.

      "EMPLOYEE" means any person, including an officer, who is an employee of
      the Company or one of its Participating Subsidiaries for tax purposes and
      who is employed at least twenty-one (21) days prior to the Grant Date of
      an Offering (or such shorter period as the Company, in its sole
      discretion, may determine).

      "EXPIRATION DATE" means the last day of an Offering as designated by the
      Committee, which, in any event, shall not be more than twenty-seven (27)
      months after the Grant Date.
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      "FAIR MARKET VALUE" shall mean on any date, with respect to a share of
      Common Stock, the closing price of a share of Common Stock as reported by
      the Consolidated Tape of New York Stock Exchange Listed Shares on such
      date, or, if no shares were traded on such Exchange on such date, on the
      next date on which the Common Stock is traded.

      "HOLDING COMPANY" means an entity that becomes a holding company for the
      Company or its business as part of any reorganization, merger,
      consolidation or other transaction, provided that the outstanding shares
      of common stock of such entity and the combined voting power of the then
      outstanding voting securities of such entity entitled to vote generally in
      the election of directors is, immediately after such reorganization,
      merger, consolidation or other transaction, beneficially owned, directly
      or indirectly, by all or substantially all of the individuals and entities
      who were the beneficial owners of the outstanding shares of common stock
      and the combined voting power of the outstanding voting securities,
      respectively, of the Company immediately prior to such reorganization,
      merger, consolidation or other transaction in substantially the same
      proportions as their ownership, immediately prior to such reorganization,
      merger, consolidation or other transaction, of such outstanding voting
      stock.

      "GRANT DATE" means the first business day of each Purchase Period of the
      Plan.

      "OFFERING" means the grant of Purchase Rights under the Plan.

      "PARTICIPATING SUBSIDIARY" means the Subsidiaries that have been
      designated by the Committee or the Board from time to time in its sole
      discretion as eligible to participate in one or more Offerings under the
      Plan; provided however that the Board shall only have the discretion to
      designate Subsidiaries if the grant of Purchase Rights to such Subsidiary
      Employees pursuant to the Plan would not cause the Company to incur
      material adverse accounting charges.

      "PLAN" means the Aetna Inc. Employee Stock Purchase Plan, a plan intended
      to qualify under Section 423 of the Code.

      "PURCHASE PERIOD" means the period of an Offering beginning on the Grant
      Date and ending on the Expiration Date.

      "PURCHASE RIGHTS" means rights to purchase shares of Common Stock under
      the Plan on the terms or conditions set forth herein and as determined by
      the Committee as provided hereunder.

      "SUBSIDIARY" means any company in an unbroken chain of companies beginning
      with (and including) the Company in which each company other than the last
      company in the unbroken chain owns stock possessing 50% or more of the
      total combined voting power of all classes of stock in one of the other
      companies in such chain.

3. ADMINISTRATION OF THE PLAN. The Committee shall administer the Plan. The
Committee shall have full power and authority to construe and interpret the Plan
and may from time to time adopt such rules and regulations for carrying out the
Plan, as it may deem best. Decisions of the Committee shall be final, conclusive
and binding upon all parties, including the Company, its shareholders and its
employees.

The Committee may in its sole discretion determine from time to time that the
Company shall grant Purchase Rights under an Offering to all of the then
eligible Employees, provided, however, that it shall be under no obligation to
do so.

4. PARTICIPATION IN THE PLAN. The individuals who shall be eligible to receive
grants of Purchase Rights under an Offering shall be all Employees of the
Company or of any Participating Subsidiary who are so employed by the Company or
Participating Subsidiary on the Grant Date of such Offering; provided, however,
that no individual shall be eligible to effect a purchase under an Offering if
immediately thereafter and after giving effect thereto, the aggregate value or
voting power of all shares of stock of the Company and any Subsidiary then owned
by such individual, either directly or indirectly, within the meaning of the
applicable sections of the Code and including all shares of stock with respect
to which such individual holds options, would equal or exceed in the aggregate
5% of the total value or combined voting power of all classes of stock of the
Company or any Subsidiary.

5. STOCK.

      (a) The stock subject to an Offering shall be authorized but unissued
      shares of Common Stock. Subject to adjustment in accordance with the
      provisions of paragraph 11(f) hereof, the total number of shares of Common
      Stock which may be the subject of Offerings under the Plan shall not
      exceed in the aggregate 6,500,000 shares.

      (b) In the event that any shares of Common Stock, which are the subject of
      an Offering, are not purchased, such unpurchased shares of Common Stock
      may again be available for subsequent Offerings.

6. NUMBER OF SHARES THAT AN EMPLOYEE MAY PURCHASE.

      (a) An eligible Employee may elect to purchase through payroll deductions
      under an Offering a number of whole shares of Common Stock determined by
      the Committee from time to time.
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      (b) The number of whole shares of Common Stock that a participating
      Employee may purchase on the Expiration Date shall be determined by
      dividing such Employee's contributions accumulated prior to such
      Expiration Date and retained in such Employee's account as of the
      Expiration Date by the applicable purchase price; provided, however, that
      such purchase shall be subject to the limitations set forth in this
      Section 6.

      (c) Notwithstanding the foregoing provisions of the Plan, no eligible
      Employee may elect to purchase under Offerings in any single calendar year
      a number of whole shares of Common Stock which, together with all other
      shares in the Company and Subsidiaries which the Employee may be entitled
      to purchase in such year pursuant to an Offering and under any other
      employee stock purchase plan, as defined in Section 423 of the Code, has
      an aggregate fair market value (measured in each case as of the Grant
      Date) in excess of $25,000.

7. PARTICIPATION.

      (a) An eligible Employee may become a participant in the Plan by
      completing a subscription agreement and any other required documents
      provided by the Company and submitting them in the form and manner
      designated by the Company.

      (b) Unless otherwise determined by the Company, payroll deductions in
      respect of an Offering shall commence on the first full payroll period
      beginning on or after the Grant Date of such Offering and shall end on the
      last payroll period ending prior to the Expiration Date of such Offering,
      unless sooner terminated by the participating Employee as provided in
      Section 10.

8. METHOD OF PAYMENT OF CONTRIBUTIONS.

      (a) A participating Employee shall elect to have payroll deductions made
      on each payday during the Offering in whole percentages from one percent
      (1%) to, and not exceeding, ten percent (10%) of such participating
      Employee's Compensation during the Offering. All payroll deductions made
      by a participating Employee shall be credited to his or her account under
      the Plan. A participating Employee may not make any additional payments
      into such account.

      (b) A participating Employee may discontinue his or her participation in
      the Plan as provided in Section 10.

      (c) Notwithstanding the foregoing, to the extent necessary to comply with
      Section 423(b)(8) of the Code and Section 6 hereof, the Company may cause
      a participant's payroll deductions to be decreased in respect of an
      Offering year to zero percent (0%).

9. EXERCISE OF PURCHASE RIGHTS. Unless a participating Employee withdraws from
the Plan as provided in Section 10, his or her right to purchase whole shares in
any Offering will be exercised automatically on each Expiration Date of an
Offering, and the maximum number of whole shares subject to the Purchase Right
will be purchased at the applicable purchase price with the accumulated
contributions in his or her account.

10. VOLUNTARY WITHDRAWALS; TERMINATION OF EMPLOYMENT.

      (a) A participating Employee may withdraw all but not less than all the
      contributions credited to his or her account under the Plan at any time
      prior to the Expiration Date of an Offering by notifying the Company in
      the form and manner designated by the Company. All of the participating
      Employee's contributions credited to his or her account will be paid to
      him or her not later than sixty (60) days after receipt of his or her
      notice of withdrawal and his or her Purchase Right for the then current
      Offering will be automatically terminated, and no further contributions
      for the purchase of Common Stock will be permitted or made during the
      Offering.

      (b) Upon termination of the participating Employee's Continuous Status as
      an Employee prior to the Expiration Date of an Offering for any reason,
      whether voluntary or involuntary, including retirement or death, the
      contributions credited to his or her account will be returned to him or
      her or, in the case of his or her death, to the Employee's estate, and his
      or her Purchase Right will be automatically terminated.

      (c) A participating Employee's withdrawal from an Offering will not have
      any effect upon his or her eligibility to participate in a succeeding
      Offering or in any similar plan that may hereafter be adopted by the
      Company.

11. TERMS AND CONDITIONS OF OFFERINGS.

      (a) General:

            The Offerings shall be in such form as the Committee shall from time
            to time approve, and shall contain such terms and conditions as the
            Committee shall prescribe not inconsistent with the Plan.

      (b) Purchase Price:
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            The purchase price per share will be established by the Committee
            for each offering but in no event will the purchase price per share
            be less than 85% of the lower of the Fair Market Value of a share of
            Common Stock on the Grant Date and the Expiration Date.

      (c) Term of Offerings:

            Each Offering shall commence on the Grant Date and terminate,
            subject to earlier termination by the Committee, on the Expiration
            Date.

      (d) Employee's Purchase Directions:

            Each Offering shall provide that the participating Employee at the
            conclusion of the Purchase Period may purchase all of the whole
            shares purchasable in such Offering with the contributions credited
            to such Employee's account unless such Employee shall, in the manner
            provided for in the Offering, notify the Company as set forth in
            Section 10 that the Employee does not desire to purchase any of such
            shares.

      (e) Change-in-Control:

            Upon a Change-in-Control, the Expiration Date shall be deemed to
            have occurred immediately prior to such Change-in-Control and,
            unless an Employee shall have withdrawn from the Plan as provided in
            Section 10, all then outstanding Purchase Rights shall be deemed to
            have been exercised on such Expiration Date as provided in Section
            9.

      (f) Adjustments:

            In the event that the Committee shall determine that any stock
            dividend, extraordinary cash dividend, recapitalization,
            reorganization, merger, consolidation, split-up, spin-off,
            combination, exchange of shares, offering to purchase Common Stock
            at a price substantially below Fair Market Value, or other similar
            event affects the Common Stock such that an adjustment is required
            in order to preserve or prevent an enlargement of the benefits or
            potential benefits intended to be made available under this Plan,
            then the Committee shall, in its sole discretion, and in such manner
            as the Committee may deem equitable, adjust any or all of (1) the
            number and kind of shares which thereafter may be made the subject
            of Offerings under the Plan, (2) the number and kind of shares
            subject to outstanding Offerings and (3) the purchase price with
            respect to any of the foregoing and/or, if deemed appropriate, make
            provision for a cash payment to a person who has outstanding
            Purchase Rights provided, however, that the number of shares subject
            to any such Purchase Rights shall always be a whole number.

      (g) Assignability:

            No rights hereunder shall be assignable or transferable.

      (h) Employee's Agreement:

            If, at the time of the purchase of shares which are covered by
            Purchase Rights under an Offering, in the opinion of counsel for the
            Company, it is necessary or desirable, in order to comply with any
            applicable laws or regulations relating to the sale of securities,
            that the Employee purchasing such shares shall agree that such
            Employee will purchase such shares for investment and not with any
            present intention to resell the same, the Employee will, upon the
            request of the Company, execute and deliver to the Company an
            agreement to such effect. The Company may also require that a legend
            setting forth such investment intention be stamped or otherwise
            written on the certificates for shares purchased pursuant to the
            Plan.

      (i) Rights as a Shareholder:

            An Employee who has been granted Purchase Rights hereunder shall
            have no rights as a shareholder with respect to shares covered by
            such Purchase Rights until the date of the issuance of the shares to
            the Employee. No adjustment will be made for dividends or other
            rights for which the record date is prior to the date of such
            issuance. For purposes of the Plan, the Company, in lieu of the
            issuance of certificates, may utilize a book entry account system
            for recording ownership of shares of Common Stock, subject to the
            rules generally applicable to such system.

      (j) Interest:

            No interest shall accrue on payroll deductions made under or
            pursuant to the Plan or any Offering hereunder.

12. TERM OF PLAN. No grant of Purchase Rights shall be made after July 1, 2006.

13. AMENDMENTS. The Plan is wholly discretionary in nature. As such, the Board
may, in its sole discretion, from time to time alter, amend, suspend, or
discontinue the Plan or alter or amend any and all Purchase Rights or terminate
any Offering; provided, however, that no such
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action of the Board may, without the approval of the shareholders, make any
amendment for which shareholder approval is necessary to comply with any tax or
regulatory requirement with which the Committee has determined it is necessary
or advisable to have the Company comply. Subject to the limitations in this
Section 13 relating to shareholder approval, the Committee may, in its sole
discretion, make such amendment or modification to the Plan or any Purchase
Rights granted hereunder as is necessary or desirable to comply with, or
effectuate administration of, the Plan under the laws, rules or regulations of
any foreign jurisdiction, the laws of which may be applicable to the Plan or its
participants hereunder.

14. APPLICATION OF FUNDS. The proceeds received by the Company from the sale of
the Common Stock pursuant to an Offering will be used for general corporate
purposes.

15. GOVERNING LAW. The Plan and all Offerings shall be construed in accordance
with and governed by the laws of the Commonwealth of Pennsylvania without regard
to the choice of law rules thereunder.

16. ADDITIONAL RESTRICTIONS OF RULE 16B-3. The terms and conditions of Purchase
Rights granted hereunder to, and the purchase of shares of Common Stock by,
persons subject to Section 16 of the Exchange Act shall comply with the
applicable provisions of Rule 16b-3 thereunder. The Plan shall be deemed to
contain, and such Purchase Rights shall contain, and the shares of Common Stock
issued upon exercise thereof shall be subject to, such additional conditions and
restrictions as may be required by such Rule 16b-3 to qualify for the maximum
exemption from such Section 16 with respect to Plan transactions.