Document:

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                                                                   EXHIBIT 10.23

                               UNUM CORPORATION

                      1990 LONG-TERM STOCK INCENTIVE PLAN

SECTION 1.  Purpose.
            -------

The purpose of the UNUM Corporation 1990 Long-Term Stock Incentive Plan (the
"Plan") is to promote the interests of UNUM Corporation and its stockholders by
(i) attracting and retaining executive officers, other key employees and
corporation directors of outstanding ability; (ii) motivating such individuals,
by means of performance-related incentives, to achieve longer-range performance
goals; and (iii) enabling such individuals to participate in the long-term
growth and financial success of UNUM Corporation.

SECTION 2.  Definitions.
            -----------

"Affiliate" shall mean any corporation or other entity which is not a Subsidiary
but as to which the Corporation possesses a direct or indirect ownership
interest and has representation on the board of directors or any similar
governing body.

"Award" shall mean a grant or award under Sections 6 through 10, inclusive, of
the Plan, as evidenced in a written document delivered to a Participant.

"Board" shall mean the Board of Directors of the Corporation.

"Code" shall mean the Internal Revenue Code of 1986, as amended from time to
time.

"Committee" shall mean the Compensation Committee of the Board.

"Common Stock" or "Stock" shall mean the common stock, $.10 par value, of the
Corporation.

"Corporation" shall mean UNUM Corporation.

"Employee" shall mean any employee of the Employer.

"Employer" shall mean the Corporation and any Subsidiary or Affiliate.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended from
time to time.

"Fair Market Value" shall mean the average of the highest and lowest sales
prices reported for consolidated trading of the Stock on the New York Stock
Exchange on the date in question, or, if the Stock shall not have been traded on
such date, the average of such highest and lowest sales prices on the first day
prior thereto on which the Stock was so traded.

"Fiscal Year" shall mean the fiscal year of the Corporation.

"Incentive Stock Option" shall mean a stock option granted under Section 6 which
is intended to meet the requirements of Section 422A of the Code.

"Limited Right" shall mean a limited stock appreciation right granted under
Section 8.

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"Non-Qualified Stock Option" shall mean a stock option granted under Section 6
which is not intended to be an Incentive Stock Option.

"Option" shall mean an Incentive Stock Option or a Non-Qualified Stock Option.

"Participant" shall mean an Employee who is selected by the Committee to receive
an Award under the Plan.

"Restricted Period" shall mean the period of years selected by the Committee
during which a grant of Restricted Stock or Restricted Stock Unit Award may be
forfeited to the Corporation.

"Restricted Stock" shall mean shares of Common Stock contingently granted to a
Participant under Section 9 of the Plan.

"Restricted Stock Unit" shall have the meaning provided in 10(a).

"Subsidiary" shall mean any business entity in which the Corporation possesses
directly or indirectly fifty percent (50%) or more of the total combined voting
power.

SECTION 3.  Administration.
            --------------

Except as provided in Section 10, the Committee shall have full power to
interpret and administer the Plan and full authority to select the individuals
to whom Awards will be granted and to determine the type and amount of Award(s)
to be granted to each Participant, the terms and conditions of Awards granted
under the Plan and the terms and conditions of the agreements which will be
entered into with Participants.  As to the selection and grant of Awards to
Participants who are not subject to Sections 16(a) and 16(b) of the Exchange
Act, or any successor sections, the Committee may delegate its responsibilities
to members of the Company's management consistent with applicable law.

The Committee shall have the authority to adopt, alter and repeal such rules,
guidelines and practices governing the Plan as it shall, from time to time, deem
advisable; to interpret the terms and provisions of the Plan and any Award
issued under the Plan (and any agreements relating thereto); to direct employees
of the Corporation and its subsidiaries or other advisors to prepare such
materials or perform such analysis as the Committee deems necessary or
appropriate; and otherwise to supervise the administration of the Plan.

Any interpretation and administration of the Plan by the Committee, and all
actions of the Committee, shall be final, binding and conclusive on the
Corporation, its stockholders, Subsidiaries, Affiliates, all Participants, their
respective legal representatives, successors and assigns and upon all persons
claiming under or through any of them.  No member of the Board or of the
Committee shall incur any liability for any action taken or omitted, or any
determination made, in good faith in connection with the Plan.

SECTION 4.  Eligibility.
            -----------

Participation in the Plan shall be limited to those key employees of the
Corporation and any Subsidiary and Affiliate selected at the sole discretion of
the Committee.

SECTION 5.  Maximum Amount Available for Awards.
            -----------------------------------

Subject to adjustment as provided in Section 12(j), the maximum number of shares
of Stock in respect of which Awards may be made under the Plan shall be a total
of 13,600,000 shares of Common Stock.

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Shares of Common Stock may be made available from the authorized but unissued
shares of the Corporation or from shares reacquired by the Corporation,
including shares purchased in the open market. In the event that (i) an Option,
or Stock Appreciation Right, or Limited Right expires or is cancelled
unexercised as to any shares of Common Stock covered thereby, or (ii) any Award
in respect of shares is forfeited for any reason under the Plan, such shares
shall thereafter be again available for award pursuant to the Plan.

SECTION 6.  Stock Options.
            -------------

(a) Grant.  Subject to the provisions of the Plan, the Committee shall have sole
    -----
    and complete authority to determine the Employees to whom Options shall be
    granted, the number of shares to be covered by each Option, the Option
    Price, as defined below, therefor and the conditions and limitations
    applicable to the exercise of the Option.  The Committee shall have the
    authority to grant Incentive Stock Options, or to grant Non-Qualified Stock
    Options, or to grant both types of Options.  In the case of Incentive Stock
    Options, the terms and conditions of such grants shall be subject to and
    comply with such rules as may be prescribed by Section 422A of the Code and
    any regulations implementing Section 422A.

(b) Option Price.  The Committee shall establish the exercise price of the
    ------------
    Option (the "Option Price") at the time each Option is granted, which Option
    Price shall not be less than 100% of the Fair Market Value of the Common
    Stock on the date of grant.

(c) Exercise.
    --------

    (1) Each Option shall be exercisable at such times and subject to such terms
        and conditions as the Committee may, in its sole discretion, specify in
        the applicable Award or thereafter; provided, however, that in no event
        may any Option granted hereunder be exercisable after the expiration of
        ten years from the date of grant.  The Committee may impose such
        conditions with respect to the exercise of Options, including without
        limitation, any relating to the application of federal or state
        securities laws, as it may deem necessary or advisable.

    (2) The Committee shall determine the methods by which the exercise price of
        an Option may be paid, the form of payment, including, without
        limitation, cash, shares of stock or other property (including "cashless
        exercise" arrangements), and the methods by which shares of stock shall
        be delivered or deemed to be delivered to Participants; provided,
        however, that if shares of stock are used to pay the exercise price of
        an option, such shares must have been held by the Participant for at
        least six months.  When shares of stock are delivered, such delivery may
        be by attestation of ownership or actual delivery of one or more
        certificates.  Failure by the Committee to specify methods by which the
        exercise price of an Option may be paid or the form of payment shall be
        deemed to express the Committee's determination that all methods and
        forms of payment presented under the Plan are permitted under the grant.

(d) Termination of Employment.
    -------------------------

    (1) Except as provided below, if a Participant ceases to be an Employee
        other than by reason of death, retirement or disability, any then
        outstanding Options may be exercised any time before their expiration
        date or within three months after the date of termination, whichever is
        earlier, but only to the extent that such Options were exercisable when
        employment ceased, absent a determination by the Committee to the
        contrary; provided, however, that a

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        Participant is terminated for cause the Committee may determine that no
        Option may be exercised at any time after the termination date.

    (2) If a Participant's employment terminates because of death or disability,
        all then outstanding Options previously granted to the Participant will
        become exercisable.  In the case of death of the Participant, such
        Options may be exercised at any time before their expiration date or
        within three years after the date of termination, whichever is earlier.
        In the case of permanent disability, such Options may be exercised at
        any time before their expiration date.

    (3) If a Participant's employment terminates because of retirement prior to
        January 1, 1995, any then outstanding Options may be exercised any time
        before their expiration date or within three years after the date of
        termination, whichever is earlier, but only to the extent that such
        Options were exercisable when employment ceased absent a determination
        by the Committee to the contrary.  If a Participant's employment
        terminates because of retirement on or after January 1, 1995, any then
        outstanding Options may be exercised any time before their expiration
        date or within five years after the date of termination, whichever is
        earlier, but only to the extent that such Options were exercisable when
        employment ceased absent a determination by the Committee to the
        contrary.

SECTION 7.  Stock Appreciation Rights.
            -------------------------

(a) The Committee shall have the authority to grant Stock Appreciation Rights in
    tandem with the grant of an Option or freestanding and unrelated to an
    Option.  Stock Appreciation Rights granted in tandem with an Option may be
    granted either at or after the time of the grant of such Option.

    Stock Appreciation Rights or any applicable portion thereof granted in
    tandem with a given Option shall only be exercisable to the extent that the
    related Option is exercisable and shall terminate and no longer be
    exercisable upon the expiration or cancellation of the related Option.

    The exercise of an Option shall result in an immediate forfeiture of any
    Stock Appreciation Right granted in tandem with that Option, and the
    exercise of such Stock Appreciation Right shall cause an immediate
    forfeiture of its related Option.  Stock Appreciation Rights shall not be
    exercisable after the expiration of ten years from date of grant.  A Stock
    Appreciation Right granted in tandem with an Option may be exercised by an
    optionee, in accordance with this Section 7, by surrendering the applicable
    portion of the related Option.  Upon such exercise and surrender, the
    optionee shall be entitled to receive an amount determined in the manner
    prescribed in this Section 7.

(b) A Stock Appreciation Right shall entitle the Participant to receive from the
    Corporation an amount equal to the excess of the Fair Market Value of a
    share of Common Stock on the date of the exercise of the Stock Appreciation
    Right over the grant price thereof, provided that the Committee may for
    administrative convenience determine that, for any Stock Appreciation Right
    which is not related to an Incentive Stock Option and can only be exercised
    during limited periods of time in order to satisfy the conditions of certain
    rules of the Securities and Exchange Commission, the exercise of any such
    Stock Appreciation Right for cash during such limited period shall be deemed
    to occur for all purposes hereunder on the day during such limited period on
    which the Fair Market Value of the Stock is the highest.  Any such
    determination by the Committee may be changed by the Committee from time to
    time and may govern the exercise of Stock Appreciation Rights granted prior
    to such determination as well as Stock Appreciation Rights thereafter
    granted.

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    The Committee shall determine whether Stock Appreciation Rights shall be
    settled in cash, shares of Common Stock or a combination of cash and shares
    of Common Stock.

SECTION 8.  Limited Rights.
            --------------

(a) The Committee shall have the authority to grant Limited Rights in tandem
    with the grant of an Option or freestanding and unrelated to an Option.
    Limited Rights granted in tandem with an Option may be granted either at or
    after the time of the grant of such Option.

    Limited Rights or any applicable portion thereof granted in tandem with a
    given Option shall terminate and no longer be exercisable upon the
    expiration or cancellation of the related Option.  The exercise of an Option
    shall result in an immediate forfeiture of any Limited Right granted in
    tandem with that Option, and the exercise of such Limited Right shall cause
    an immediate forfeiture of its related Option.

    A Limited Right granted in tandem with an Option may be exercised by an
    optionee, in accordance with this Section 8, by surrendering the applicable
    portion of the related Option.  Upon such exercise and surrender, the
    optionee shall be entitled to receive an amount determined in the manner
    prescribed in this Section 8.

(b) Limited Rights shall only be exercisable during the 30 day period following
    a Change in Control as defined in Section 11 and shall not be exercisable
    after the expiration of ten years from the date of grant.

(c) Upon the exercise of a Limited Right, an optionee shall be entitled to
    receive from the Corporation an amount in cash equal in value to the excess
    of (i) the higher of (A) the highest price per share paid in connection with
    the Change in Control or (B) the highest Fair Market Value per share as
    reported in the Wall Street Journal at any time during the 60 day period
    preceding the Change in Control over (ii) in the case of a Limited Right
    granted in tandem with an Option, the Option Price per share specified in
    the related Option and in the case of all other Limited Rights, the price
    per share established in the grant of the Limited Right, such excess to be
    multiplied by the number of shares in respect of which the Limited Right
    shall have been exercised; provided, however, that upon the exercise of a
    Limited Right granted in tandem with an Incentive Stock Option, the amount
    set forth in clause (i) shall not exceed the Fair Market Value of a share on
    the date of exercise of the Limited Right.

(d) Limited Rights shall be subject to such other terms and conditions, not
    inconsistent with the provisions of the Plan, as shall be determined from
    time to time by the Committee.  This Section 8 shall be interpreted in
    accordance and consistent with the principles set forth in Rule 16b-3 of the
    Exchange Act.

SECTION 9.  Restricted Stock.
            ----------------

(a) Subject to the provisions of the Plan, the Committee shall have sole and
    complete authority to determine the Employees to whom shares of Restricted
    Stock shall be granted, the number of shares of Restricted Stock to be
    granted to each Participant, the duration of the Restricted Period during
    which, and the conditions under which, the Restricted Stock may be forfeited
    to the Corporation, and the other terms and conditions of such Awards.  The
    Committee may determine that the Restricted Period applicable to a
    particular grant may vary depending upon the attainment of particular
    conditions, such as corporate earnings, share price or other targets set by
    the Committee.

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(b) Shares of Restricted Stock may not be sold, assigned, transferred, pledged
    or otherwise encumbered, except as herein provided, during the Restricted
    Period.  Certificates issued in respect of shares of Restricted Stock shall
    be registered in the name of the Participant and deposited by such
    Participant, together with a stock power endorsed in blank, with the
    Corporation.  At the expiration of the Restricted Period, the Corporation
    shall deliver such certificates to the Participant or the Participant's
    legal representative.

(c) If a Participant's employment terminates by reasons of disability or death,
    any Restricted Stock held by such Participant shall thereafter vest and any
    restriction lapse, to the extent such Restricted Stock would have become
    vested and no longer subject to such restrictions within one year from the
    time of termination had the Participant continued to fulfill all of the
    conditions of the Restricted Stock during such period (or on such
    accelerated basis as the Committee may determine at or after grant).  Unless
    otherwise determined by the Committee, if a Participant's employment
    terminates for any reasons other than permanent disability or death, any
    Restricted Stock which is unvested or subject to restriction shall thereupon
    be forfeited.

SECTION 10.  Restricted Stock Units.
             ----------------------

(a) The Committee may, in its discretion, grant Restricted Stock Units to such
    eligible Participants as it may select.  Restricted Stock Units shall
    entitle the Participant to receive one share of Common Stock per Unit at the
    times and subject to the conditions determined by the Committee.  The
    Committee shall determine the number of Units to be granted to each
    Participant, whether or not the Restricted Stock Units are designed to
    satisfy the requirements of Section 162(m) of the Code and the regulations
    thereunder, the duration of the Restricted Period (if any) during which, and
    the conditions under which, the Restricted Stock Units may be forfeited to
    the Corporation, the schedule for settlement, and any other terms and
    conditions relating to each grant, not inconsistent with the terms of this
    Plan, as the Committee shall deem advisable.  The Committee may provide that
    the holder of a Restricted  Stock Unit Award shall receive cash or Common
    Stock equal in value to the dividends paid with respect to a specified
    number of shares of the Common Stock, as such dividends accrue or upon
    settlement of the Restricted Stock Unit Award, in which case dividends may
    be deemed to have been reinvested in additional Common Stock or such other
    investment vehicles as the Committee may specify.

(b) Restricted Stock Units may not be sold, assigned, transferred, pledged or
    otherwise encumbered.

(c) Subject to the renumbered Section 12 of this Plan, all of the provisions
    governing the satisfaction of Performance Measures and the termination of
    the Restriction Period relating to a Restricted Stock Unit Award, or any
    cancellation or forfeiture of shares of Restricted Stock Units upon
    termination of employment of the Participant, whether by reason of death,
    permanent disability, retirement, or otherwise, shall be set forth in the
    Agreement relating to such Restricted Stock Unit Award, or in guidelines
    established by the Committee and made applicable to such Restricted Stock
    Unit Award.

SECTION 11.  Non-Employee Director Options.
             -----------------------------

Notwithstanding any of the other provisions of the Plan to the contrary, the
provisions of this Section 10 shall only apply to a non-employee member of the
Board.  The other provisions of the Plan shall apply to grants of Options under
this Section 10 to the extent not inconsistent with the provisions of this
Section.

(a)  This Section 11 shall be administered by the Board.

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(b)  Each non-employee member of the Board shall receive Non-Qualified Stock
     Options in accordance with the provisions of this Section 11.

(c)  (i)  Recipients of Options under this Section 11 shall enter into a stock
          option agreement with the Corporation, which agreement shall set
          forth, among other things, the exercise price of the Option, the term
          of the Option and provisions regarding exercisability of the Option
          granted thereunder.

    (ii)  On the Effective Date (as defined below) each non-employee member of
          the Board of the Corporation shall receive Options to purchase 2,000
          shares of Common Stock. Beginning in 1997, on the date after each
          annual stockholders meeting of the Corporation each continuing non-
          employee member of the Board shall be granted an Option to purchase
          4,000 shares of Common Stock and, beginning in 1990, each newly
          elected non-employee director shall be granted an Option to purchase
          6,000 shares of Common Stock. The Option Price per share of Common
          Stock purchasable under such Options shall be equal to the Fair Market
          Value of the Common Stock on the date of grant. Such Option shall
          remain exercisable until the earlier of ten years from the date of
          grant or the termination of any post-directorship consultancy
          agreement with the Corporation; provided, however, that if such
                                          --------  -------
          consultancy agreement terminates by reason of death or disability any
          then outstanding Options may be exercised (x) at any time before their
          expiration date or (y), if such termination is by reason of death,
          within three years of the date of death, whichever is earlier. Such
          Options shall be exercisable one year from the date of grant by
          payment in full in cash or in shares of Common Stock having a Fair
          Market Value equal to the Option Price or in a combination of cash and
          such shares.

(d) The Board may not amend, alter, or discontinue this Section 11 without the
    approval of the stockholders of the Corporation.

SECTION 12.  Change of Control.
             -----------------

Notwithstanding anything to the contrary contained herein, and notwithstanding
any contrary waiting period or installment period in any agreement relating to
an Award or in the Plan, each outstanding Option, Stock Appreciation Right and
Limited Right granted under the Plan shall become exercisable in full for the
aggregate number of shares covered thereby, and any restriction or deferral
limitation applicable to any Restricted Stock or Restricted Stock Units shall
lapse and such shares and Awards shall be deemed fully vested, in the event of a
Change in Control (as hereinafter defined).

For purposes of this Plan, a Change in Control shall be deemed to have occurred
upon the first to occur of the following events:

    (i) any "person," as such term is used in Sections 13(d) and 14(d) of the
        Exchange Act (other than the Corporation or any corporation owned,
        directly or indirectly, by the stockholders of the Corporation in
        substantially the same proportions as their ownership of stock of the
        Corporation), is or becomes the "beneficial owner" (as defined in Rule
        13d-3 under the Exchange Act), directly or indirectly, of securities of
        the Corporation representing more than 40% of the number of the
        Corporation's then outstanding securities;

   (ii) during any period of two consecutive years, individuals who at the
        beginning of such period constitute the Board, and any new director
        (other than a director designated by a person who has entered into an
        agreement with the Corporation to effect a transaction

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        described in Subsection 12(i), (iii) or (iv) of this Section 12) whose
        election by the Board or nomination for election by the Corporation's
        stockholders was approved by a vote of at least two-thirds (2/3) of the
        directors then still in office who either were directors at the
        beginning of the period or whose election or nomination for election was
        previously so approved, cease for any reason to constitute at least a
        majority thereof;

  (iii) the stockholders of the Corporation approve a merger or consolidation
        of the Corporation with any other corporation, other than a merger or
        consolidation which would result in the voting securities of the
        Corporation outstanding immediately prior thereto continuing to
        represent (either by remaining outstanding or being converted into
        voting securities of the surviving entity) more than 60% of the number
        of outstanding securities of the Corporation or such surviving entity
        outstanding immediately after such merger or consolidation; or

   (iv) the stockholders of the Corporation approve a plan of complete
        liquidation of the Corporation or an agreement for the sale or
        disposition by the Corporation of all or substantially all of the
        Corporation's assets.

SECTION 13.  General Provisions.
             ------------------

(a) Income Tax Withholding.  The Corporation shall have the authority and the
    ----------------------
    right to deduct or withhold, or require a Participant to remit to the
    Corporation, an amount sufficient to satisfy federal, state, and local taxes
    (including the participant's FICA obligation) required by law to be withheld
    with respect to any taxable event arising as a result of the Plan.  With
    respect to withholding required upon any taxable event under the Plan, the
    Committee may, at the time the Award is granted or thereafter, require or
    permit that any such withholding requirement be satisfied, in whole or in
    part, by withholding from the award shares of stock having a Fair Market
    Value on the date of withholding equal to the minimum amount (and not any
    greater amount) required to be withheld for tax purposes, all in accordance
    with such procedures as the Committee establishes.

(b) Nontransferability.  No Award shall be assignable or transferable, and no
    ------------------
    right or interest of any Participant shall be subject to any lien,
    obligation or liability of the Participant, except by will or the laws of
    descent and distribution.

(c) No Right to Employment.  No person shall have any claim or right to be
    ----------------------
    granted an Award, and the grant of an Award shall not be construed as giving
    a Participant the right to be retained in the employ of the Employer.
    Further, the Employer expressly reserves the right at any time to dismiss a
    Participant free from any liability, or any claim under the Plan, except as
    provided herein or in any agreement entered into with respect to an Award.

(d) No Rights as Stockholder.  Subject to the provisions of the applicable
    ------------------------
    Award, no Participant or transferee of an Option or Restricted Stock Units
    shall have any rights as a stockholder with respect to any shares of Common
    Stock to be distributed under the Plan until he or she has become the holder
    thereof.  Notwithstanding the foregoing, in connection with each grant of
    Restricted Stock hereunder, the applicable Award shall specify if and to
    what extent the Participant shall not be entitled to the rights of a
    stockholder in respect of such Restricted Stock.

(e) Construction of the Plan.  The validity, construction, interpretation,
    ------------------------
    administration and effect of the Plan and of its rules and regulations, and
    rights relating to the Plan, shall be determined solely in accordance with
    the laws of the State of Delaware.

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(f) Effective Date.  Subject to the approval of the stockholders of the
    --------------
    Corporation, the Plan shall be effective on February 9, 1990 (the "Effective
    Date").  No Options or Awards may be granted under the Plan after February
    9, 2000.

(g) Amendment of Plan.  The Board may amend, suspend or terminate the Plan or
    -----------------
    any portion thereof at any time, provided that no amendment shall be made
    without stockholder approval if such approval is necessary to comply with
    any tax or regulatory requirement, including for these purposes any approval
    requirement which is a prerequisite for exemptive relief under Section 16(b)
    of the Exchange Act.  Notwithstanding anything to the contrary contained
    herein, the Committee may amend the Plan in such manner as may be necessary
    so as to have the Plan conform with local rules and regulations.  The Chief
    Executive Officer shall be authorized to make minor or administrative
    modifications to the Plan as well as modification to the Plan which may be
    dictated by requirements of federal or state statutes applicable to the
    Corporation or authorized or made desirable by such statutes.  No
    modification or termination of the Plan shall, without the optionee's
    consent, alter or impair any of his or her rights or obligations under any
    Option, Stock Appreciation Right or Limited Right theretofore granted to him
    or her under the Plan.

(h) Amendment of Award.  The Committee may amend, modify or terminate any
    ------------------
    outstanding Award with the Participant's consent at any time prior to
    payment or exercise in any manner not inconsistent with the terms of the
    Plan, including without limitation, (i) to change the date or dates as of
    which (A) an Option, Stock Appreciation Right or Limited Right becomes
    exercisable; (B) Restricted Stock or Restricted Stock Units becomes
    nonforfeitable; or (ii) to cancel and reissue an Award under such different
    terms and conditions as it determines appropriate.

(i) Hardship Distributions.  In no event shall any Option granted under this
    ----------------------
    Plan be exercisable through payment of the Option Price in cash during the
    period of one year following a hardship distribution under the UNUM
    Employees Retirement Savings Plan and Trust, as defined therein.

    Adjustments and Assumption.  In the event of a reorganization,
    --------------------------
    recapitalization, stock split, stock dividend, combination of shares,
    merger, consolidation, distribution of assets, or any other change in the
    corporate structure or shares of the Corporation, the Committee shall make
    such adjustments as it deems appropriate in the number and kind of shares
    authorized by the Plan, in the number and kind of shares covered by the
    Awards granted, and in the purchase price of outstanding Options.  In the
    event of any merger, consolidation or other reorganization in which the
    Corporation is not the surviving or continuing corporation, all Awards
    granted hereunder and outstanding on the date of such event shall be assumed
    by the surviving or continuing corporation with appropriate adjustment as to
    the number and kind of shares and purchase price of the shares.

(k) In addition to the purposes set forth in Section 1, the Committee may grant
    Awards to eligible Participants in order to compensate such Participants to
    surrender existing rights to receive benefits from the Employer under this
    or any other benefit plan or arrangement.

                                       9<PAGE>

                                                                   EXHIBIT 10.24

                               UNUM CORPORATION

                      1996 LONG-TERM STOCK INCENTIVE PLAN

SECTION 1.  Purpose.
            -------

The purpose of the UNUM Corporation 1996 Long-Term Stock Incentive Plan (the
"Plan") is to promote the interests of UNUM Corporation and its stockholders by
(i) attracting and retaining executive officers and other key employees of
outstanding ability; (ii) motivating such individuals, by means of performance-
related incentives, to achieve longer-range performance goals; and (iii)
enabling such individuals to participate in the long-term growth and financial
success of UNUM Corporation.

SECTION 2.  Definitions.
            -----------

"Affiliate" shall mean any corporation or other entity which is not a Subsidiary
but as to which the Corporation possesses a direct or indirect ownership
interest and has representation on the board of directors or any similar
governing body.

"Award" shall mean a grant or award under Sections 6 through 10, inclusive, of
the Plan, as evidenced in a written document delivered to a Participant.

"Board" shall mean the Board of Directors of the Corporation.

"Code" shall mean the Internal Revenue Code of 1986, as amended from time to
time.

"Committee" shall mean the Compensation Committee of the Board, or, to the
extent necessary to satisfy the requirements of Section 162(m) of the Code, a
subcommittee thereof.

"Common Stock" or "Stock" shall mean the common stock, $.10 par value, of the
Corporation.

"Corporation" shall mean UNUM Corporation.

"Employee" shall mean any employee of the Employer.

"Employer" shall mean the Corporation and any Subsidiary or Affiliate.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended from
time to time.

"Fair Market Value" shall mean the average of the highest and lowest sales
prices reported for consolidated trading of the Stock on the New York Stock
Exchange on the date in question, or, if the Stock shall not have been traded on
such date, the average of such highest and lowest sales prices on the first day
prior thereto on which the Stock was so traded.

"Fiscal Year" shall mean the fiscal year of the Corporation.

"Incentive Stock Option" shall mean a stock option granted under Section 6 which
is intended to meet the requirements of Section 422 of the Code.

"Limited Right" shall mean a limited stock appreciation right granted under
Section 8.

                                       1
<PAGE>

"Non-Qualified Stock Option" shall mean a stock option granted under Section 6
which is not intended to be an Incentive Stock Option.

"Option" shall mean an Incentive Stock Option or a Non-Qualified Stock Option.

"Participant" shall mean an Employee who is selected by the Committee to receive
an Award under the Plan.

"Performance Measures" shall mean the criteria and objectives, established by
the Committee, which shall be satisfied as a condition to the receipt of shares
by a Participant under a Restricted Stock Award, or to the payment or receipt of
shares or cash under a Restricted Stock Unit or Performance Share Award.  With
respect to any Restricted Stock, Restricted Stock Unit or Performance Share
Award which the Committee designates as being intended to satisfy the
requirements of Section 162(m) of the Code and the regulations thereunder, such
criteria and objectives shall be based on one or more of the following: the
market price of a share of the Common Stock; earnings per share, return to
stockholders (including dividends), return on equity, earnings of the
Corporation on a GAAP or statutory accounting basis, revenues, market share,
cash flow or cost reduction goals, underwriting margin, or any combination of
the foregoing.  Such criteria and objectives may be expressed on either an
absolute basis or relative to the performance of a peer group selected by the
Committee. In the case of any Restricted Stock or Performance Share Award which
the Committee does not designate as being intended to satisfy the requirements
of Section 162(m) of the Code and the regulations thereunder, such criteria and
objectives, if any, may include one or more of the criteria and objectives
referred to above or such other criteria and objectives as the Committee may
determine.

"Performance Period" shall mean a period designated by the Committee during
which the Performance Measures applicable to a Performance Share Award shall be
measured.

"Performance Share" shall mean a right, granted to a Participant under Section
10 of this Plan, contingent upon the attainment of specified Performance
Measures within a specified Performance Period, to receive one share of Common
Stock, which may be Restricted Stock, or in lieu thereof, the Fair Market Value
of such Performance Share in cash.

"Restricted Stock" shall mean shares of Common Stock contingently granted to a
Participant under Section 9 of this Plan.

"Restricted Stock Unit" shall have the meaning provided in Section 10(a).

"Restriction Period" shall mean a period designated by the Committee during
which the Performance Measures and other conditions applicable to a Restricted
Stock Award, Restricted Stock Unit Award or Performance Share Award shall be
measured.

"Stock Appreciation Right" shall mean an Award granted under Section 7 of the
Plan.

"Subsidiary" shall mean any business entity in which the Corporation possesses
directly or indirectly fifty percent (50%) or more of the total combined voting
power.

"Voting Securities" shall mean securities which are entitled to cast votes as to
general corporate matters, including the election of directors.

                                       2
<PAGE>

SECTION 3.  Administration.
            --------------

The Committee shall have full power to interpret and administer the Plan and
full authority to select the individuals to whom Awards will be granted and to
determine the type and amount of Award(s) to be granted to each Participant, the
terms and conditions of Awards granted under the Plan and the terms and
conditions of the agreements which will be entered into with Participants.

The Committee shall have the authority to adopt, alter and repeal such rules,
guidelines and practices governing the Plan as it shall, from time to time, deem
advisable; to interpret the terms and provisions of the Plan and any Award
issued under the Plan (and any agreements relating thereto); to direct employees
of the Corporation and its subsidiaries or other advisors to prepare such
materials or perform such analysis as the Committee deems necessary or
appropriate; and otherwise to supervise the administration of the Plan.  The
Committee may delegate such of its responsibilities set forth above to members
of the Corporation's management as the Committee may determine, with regard to
the grant, amendment, interpretation and administration of Awards to
Participants who are not subject to Sections 16(a) and 16(b) of the Exchange
Act, and except with respect to Awards which are designed to satisfy the
requirements of Section 162(m) of the Code and the regulations thereunder.

Any interpretation and action under this Plan by the Committee, or members of
the Corporation's management acting under authority delegated by the Committee,
shall be final, binding and conclusive on the Corporation, its stockholders,
Subsidiaries, Affiliates, all Participants, their respective legal
representatives, successors and assigns and upon all persons claiming under or
through any of them.  Neither any member of the Board of Directors or of the
Committee nor any member of the Corporation's management acting under authority
delegated by the Committee shall incur any liability for any action taken or
omitted, or any determination made, in good faith in connection with the Plan.

SECTION 4.  Eligibility.
            -----------

Participation in the Plan shall be limited to those key employees of the
Corporation and any Subsidiary and Affiliate selected at the sole discretion of
the Committee.

SECTION 5.  Maximum Amount Available for Awards.
            -----------------------------------

Subject to adjustment as provided in Section 12(j), the maximum number of shares
of Stock in respect of which Awards may be made under the Plan shall be a total
of 7,000,000 shares of Common Stock, provided that during any single calendar
year (i) Options shall not be granted to any individual Participant to purchase
more than 400,000 shares of the Common Stock, and (ii) the sum of all shares of
Restricted Stock plus all Restricted Stock Units plus all Performance Shares
granted to any individual Participant shall not exceed 200,000.  Common Stock
may be made available from the authorized but unissued shares of the Corporation
or from shares reacquired by the Corporation, including shares purchased in the
open market.  In the event that (i) an Option, or Stock Appreciation Right, or
Limited Right expires, terminates, or is canceled, surrendered or exchanged
unexercised as to any shares of Common Stock covered thereby, or (ii) any other
Award in respect of shares is forfeited for any reason under the Plan, such
shares shall thereafter be again available for award pursuant to the Plan.

SECTION 6.  Stock Options.
            --------------

(a)  Grant.  The Committee may, in its discretion, grant Options to such
     -----
     eligible Participants as it may select.  The Committee shall determine the
     number of shares to be covered by each Option, the

                                       3
<PAGE>

     Option Price, as defined below, therefor and the conditions and limitations
     applicable to the exercise of the Option. The Committee shall have the
     authority to grant Incentive Stock Options, or to grant Non-Qualified Stock
     Options, or to grant both types of Options. In the case of Incentive Stock
     Options, the terms and conditions of such grants shall be subject to and
     comply with such rules as may be prescribed by Section 422 of the Code and
     any regulations implementing Section 422.

(b)  Option Price.  The Committee shall establish the exercise price of the
     ------------
     Option (the "Option Price") at the time each Option is granted, which
     Option Price shall not be less than 100% of the Fair Market Value of the
     Common Stock on the date of grant.

(c) Exercise.
    --------

    (1)  Each Option shall be exercisable at such times and subject to such
         terms and conditions as the Committee may, in its sole discretion,
         specify in the applicable Award or thereafter; provided, however, that
         in no event may any Option granted hereunder be exercisable after the
         expiration of ten years from the date of grant. The Committee may
         impose such conditions with respect to the exercise of Options,
         including without limitation, any relating to the application of
         federal or state securities laws, as it may deem necessary or
         advisable.

    (2)  The Committee shall determine the methods by which the exercise price
         of an Option may be paid, the form of payment, including, without
         limitation, cash, shares of stock, or other property (including
         "cashless exercise" arrangements), and the methods by which shares of
         stock shall be delivered or deemed to be delivered to Participants;
         provided, however, that if shares of stock are used to pay the exercise
         price of an option, such shares must have been held by the Participant
         for at least six months. When shares of stock are delivered, such
         delivery may be by attestation of ownership or actual delivery of one
         or more certificates. Failure by the Committee to specify methods by
         which the exercise price of an Option may be paid or the form of
         payment shall be deemed to express the Committee's determination that
         all methods and forms of payment presented under the Plan are permitted
         under the grant.

(d)  Termination of Employment.
     -------------------------

     (1) If a Participant ceases to be an Employee other than by reason of
         death, retirement or permanent disability, any then outstanding Options
         may be exercised at any time before their expiration date or within
         three months after the date of termination, whichever is earlier, but
         only (unless otherwise determined by the Committee) to the extent that
         such Options were exercisable when employment ceased, and to the extent
         not so exercisable, the Option shall terminate on the date employment
         ceases; provided, however, that if a Participant is terminated for
         cause the Committee may determine that no Option may be exercised at
         any time after the termination date.

     (2) If a Participant's employment terminates because of death or permanent
         disability, all then outstanding Options previously granted to the
         Participant will become exercisable.  In the case of death of the
         Participant, such Options may be exercised at any time before their
         expiration date or within three years after the date of termination,
         whichever is earlier.  In the case of permanent disability, such
         Options may be exercised at any time before their expiration date.

                                       4
<PAGE>

    (3)  If a Participant's employment terminates because of retirement, any
         then outstanding Options may be exercised at any time before their
         expiration date or within five years after the date of termination,
         whichever is earlier, but only (unless otherwise determined by the
         Committee) to the extent that such Options were exercisable when
         employment ceased, and to the extent not so exercisable, the Option
         shall terminate on the date employment ceases.

SECTION 7.  Stock Appreciation Right.
            ------------------------

(a) The Committee shall have the authority to grant Stock Appreciation Rights in
    tandem with the grant of an Option or freestanding and unrelated to an
    Option.  Stock Appreciation Rights granted in tandem with an Option may be
    granted either at or after the time of the grant of such Option.

    Stock Appreciation Rights or any applicable portion thereof granted in
    tandem with a given Option shall only be exercisable to the extent that the
    related Option is exercisable and shall terminate and no longer be
    exercisable upon the expiration, termination, or cancellation of the related
    Option.

    The exercise of an Option shall result in an immediate forfeiture of any
    Stock Appreciation Right granted in tandem with that Option, and the
    exercise of such Stock Appreciation Right shall cause an immediate
    forfeiture of its related Option. Stock Appreciation Rights shall not be
    exercisable after the expiration of ten years from date of grant.  A Stock
    Appreciation Right granted in tandem with an Option may be exercised by an
    optionee, in accordance with this Section 7, by surrendering the applicable
    portion of the related Option.  Upon such exercise and surrender, the
    optionee shall be entitled to receive an amount determined in the manner
    prescribed in this Section 7.

(b) A Stock Appreciation Right shall entitle the Participant to receive from the
    Corporation an amount equal to the excess of the Fair Market Value of a
    share of Common Stock on the date of the exercise of the Stock Appreciation
    Right over the grant price thereof, provided that the Committee may for
    administrative convenience determine that, for any Stock Appreciation Right
    which is not related to an Incentive Stock Option and can only be exercised
    during limited periods of time in order to satisfy the conditions of certain
    rules of the Securities and Exchange Commission, the exercise of any such
    Stock Appreciation Right for cash during such limited period shall be deemed
    to occur for all purposes hereunder on the day during such limited period on
    which the Fair Market Value of the Stock is the highest.  Any such
    determination by the Committee may be changed by the Committee from time to
    time and may govern the exercise of Stock Appreciation Rights granted prior
    to such determination as well as Stock Appreciation Rights thereafter
    granted.  The Committee shall determine whether Stock Appreciation Rights
    shall be settled in cash, shares of Common Stock or a combination of cash
    and shares of Common Stock.

SECTION 8.  Limited Rights.
            --------------

(a) The Committee shall have the authority to grant Limited Rights in tandem
    with the grant of an Option or freestanding and unrelated to an Option.
    Limited Rights granted in tandem with an Option may be granted either at or
    after the time of the grant of such Option.

    Limited Rights or any applicable portion thereof granted in tandem with a
    given Option shall terminate and no longer be exercisable upon the
    expiration, termination or cancellation of the

                                       5
<PAGE>

    related Option. The exercise of an Option shall result in an immediate
    forfeiture of any Limited Right granted in tandem with that Option, and the
    exercise of such Limited Right shall cause an immediate forfeiture of its
    related Option.

    A Limited Right granted in tandem with an Option may be exercised by an
    optionee, in accordance with this Section 8, by surrendering the applicable
    portion of the related Option.  Upon such exercise and surrender, the
    optionee shall be entitled to receive an amount determined in the manner
    prescribed in this Section 8.

(b) Limited Rights shall only be exercisable during the 30 day period following
    a Change in Control as defined in Section 11 and shall not be exercisable
    after the expiration of ten years from the date of grant.

(c) Upon the exercise of a Limited Right, an optionee shall be entitled to
    receive from the Corporation an amount in cash equal in value to the excess
    of (i) the higher of (A) the highest price per share paid in connection with
    the Change in Control or (B) the highest Fair Market Value per share as
    reported in the Wall Street Journal at any time during the 60 day period
    preceding the Change in Control over (ii) in the case of a Limited Right
    granted in tandem with an Option, the Option Price per share specified in
    the related Option and in the case of all other Limited Rights, the price
    per share established in the grant of the Limited Right (which shall not be
    less than the Fair Market Value of a share of Common Stock on the date of
    grant), such excess to be multiplied by the number of shares in respect of
    which the Limited Right shall have been exercised; provided, however, that
    upon the exercise of a Limited Right granted in tandem with an Incentive
    Stock Option, the amount set forth in clause (i) shall not exceed the Fair
    Market Value of a share on the date of exercise of the Limited Right.

(d) Limited Rights shall be subject to such other terms and conditions, not
    inconsistent with the provisions of the Plan, as shall be determined from
    time to time by the Committee.  This Section 8 shall be interpreted in
    accordance and consistent with the principles set forth in Rule 16b-3 of the
    Exchange Act.

SECTION 9.  Restricted Stock.
            ----------------

(a) Grant.  The Committee may, in its discretion, grant shares of Restricted
    -----
    Stock to such eligible Participants as it may select.  The Committee shall
    determine the number of shares of Restricted Stock to be granted to each
    Participant, whether or not the Restricted Stock Award is designed to
    satisfy the requirements of Section 162(m) of the Code and the regulations
    thereunder, the duration of the Restriction Period (if any) during which,
    and the conditions under which, the Restricted Stock may be forfeited to the
    Corporation, and the other terms and conditions of such Awards.  The
    Committee may condition the vesting of shares of Restricted Stock on
    Performance Measures to be attained by the Corporation and/or the
    Participant over a stated Performance Period.

(b) Assignability.  Shares of Restricted Stock may not be sold, assigned,
    -------------
    transferred, pledged or otherwise encumbered, except as herein provided,
    during the Restriction Period.

(c) Dividends.  The Committee shall determine whether dividends payable on
    ---------
    shares of Restricted Stock shall be paid to the Participant during the
    Restriction Period or held in a suspense account for payment (with or
    without interest) to the Participant only in the event of the vesting of the
    underlying shares of Restricted Stock.

                                       6
<PAGE>

(d) Termination of Employment.  Subject to Section 11 of this Plan, all of the
    -------------------------
    provisions governing the satisfaction of Performance Measures and the
    termination of the Restriction Period relating to a Restricted Stock Award,
    or any cancellation or forfeiture of shares of Restricted Stock upon
    termination of employment of the Participant, whether by reason of death,
    permanent disability, retirement, or otherwise, shall be set forth in the
    Agreement relating to such Restricted Stock Award, or in guidelines
    established by the Committee and made applicable to such Restricted Stock
    Award.

SECTION 10. Restricted Stock Units.
            -----------------------

(a) Grant.  The Committee may, in its discretion, grant Restricted Stock Units
    -----
    to such eligible Participants as it may select. Restricted Stock Units shall
    entitle the Participant to receive one share of Common Stock per Unit at the
    times and subject to the conditions determined by the Committee.  The
    Committee shall determine the number of Units to be granted to each
    Participant, whether or not the Restricted Stock Units are designed to
    satisfy the requirements of Section 162(m) of the Code and the regulations
    thereunder, the duration of the Restricted Period (if any) during which, and
    the conditions under which, the Restricted Stock Units may be forfeited to
    the Corporation, the schedule for settlement, and any other terms and
    conditions relating to each grant, not inconsistent with the terms of this
    Plan, as the Committee shall deem advisable.  The Committee may provide that
    the holder of a Restricted Stock Unit Award shall receive cash or Common
    Stock equal in value to the dividends paid with respect to a specified
    number of shares of the Common Stock, as such dividends accrue or upon
    settlement of the Restricted Stock Unit Award, in which case dividends may
    be deemed to have been reinvested in additional Common Stock or such other
    investment vehicles as the Committee may specify.

(b) Assignability.  Restricted Stock Units may not be sold, assigned,
    -------------
    transferred, pledged or otherwise encumbered.

(c) Termination of Employment.  Subject to the renumbered Section 12 of this
    -------------------------
    Plan, all of the provisions governing the satisfaction of Performance
    Measures and the termination of the Restriction Period relating to a
    Restricted Stock Unit Award, or any cancellation or forfeiture of shares of
    Restricted Stock Units upon termination of employment of the Participant,
    whether by reason of death, permanent disability, retirement, or otherwise,
    shall be set forth in the Agreement relating to such Restricted Stock Unit
    Award, or in guidelines established by the Committee and made applicable to
    such Restricted Stock Unit Award.

SECTION 11. Performance Share Awards.
            ------------------------

(a) Grant.  The Committee may, in its discretion, grant Performance Share Awards
    -----
    to such eligible Participants as it may select.  The Committee shall
    determine the number of Performance Shares to be granted to each
    Participant, whether or not the Performance Share Award is designed to
    satisfy the requirements of Section 162(m) of the Code and the regulations
    thereunder, the Performance Measures and Performance Period applicable to
    each grant, and any other terms and conditions relating to each grant, not
    inconsistent with the terms of this Plan, as the Committee shall deem
    advisable.

(b)  Settlement.  The Agreement relating to a Performance Share Award (i) shall
     ----------
     specify whether such award may be settled in shares of Common Stock
     (including shares of Restricted Stock) or cash or a combination thereof;
     and (ii) may specify whether the holder thereof shall be entitled to
     receive,

                                       7
<PAGE>

     on a current or deferred basis, dividend equivalents, and if determined by
     the Committee, interest on any deferred dividend equivalents with respect
     to the number of shares of Common Stock subject to such Award. Prior to the
     settlement of a Performance Share Award in shares of Common Stock,
     including Restricted Stock, the holders of such award shall have no rights
     as a stockholder of the Corporation with respect to the shares of Common
     Stock subject to such Award.

(c)  Termination of Employment.  Subject to Section 12 of this Plan, all of the
     -------------------------
     terms relating the satisfaction of Performance Measures and the termination
     of the Performance Period relating to a Performance Share Award, or any
     cancellation or forfeiture of such Performance Share Award upon a
     termination of employment, whether by reason of death, disability,
     retirement, or otherwise, shall be set forth in the Agreement relating to
     such Performance Share Award, or in guidelines established by the Committee
     and made applicable to such Performance Share Award.

SECTION 12.  Change of Control.
             -----------------

Notwithstanding anything to the contrary contained herein, and notwithstanding
any contrary waiting period or installment period in any agreement relating to
an Award or in the Plan, in the event of a Change in Control (as hereinafter
defined), (i) each outstanding Option, Stock Appreciation Right and Limited
Right granted under the Plan shall become exercisable in full for the aggregate
number of shares covered thereby; (ii) any Performance Measure relating to any
Restricted Stock, Restricted Stock Units or Performance Share Award (including
any Restricted Stock already granted or to be granted in satisfaction of a
Performance Share Award) shall be deemed to be satisfied at the maximum level;
and (iii) any Restriction Period and/or Performance Period relating to any
Restricted Stock, Restricted Stock Units or Performance Share Award (including
any Restricted Stock already granted or to be granted in satisfaction of a
Performance Share Award) shall lapse (and any other conditions pertaining to the
vesting of any such Award shall be waived) and such shares and Awards shall be
deemed fully vested.

For purposes of this Plan, a Change in Control shall be deemed to have occurred
upon the first to occur of the following events:

        any "person," as such term is used in Sections 13(d) and 14(d) of the
        Exchange Act (other than the Corporation, a trustee or other fiduciary
        holding Voting Securities under an employee benefit plan of the
        Corporation, or any corporation owned, directly or indirectly, by the
        stockholders of the Corporation in substantially the same proportions as
        their ownership of stock of the Corporation), is or becomes the
        "beneficial owner" (as defined in Rule 13d-3 under the Exchange Act),
        directly or indirectly, of securities of the Corporation representing
        more than 40% of the number of the Corporation's then outstanding Voting
        Securities, excluding any "person" who becomes such a beneficial owner
        in connection with an Excluded Transaction described in clause (iii)
        below;

   (ii) the following individuals cease for any reason to constitute a majority
        of the directors then serving: individuals who on January 1, 1996,
        constitute the Board, and any new director (other than a director whose
        initial assumption of office is in connection with an actual or
        threatened election contest, including but not limited to a consent
        solicitation, relating to the election of directors of the Corporation)
        whose appointment or election by the Board or nomination for election by
        the Corporation's stockholders was approved by a vote of at least two-
        thirds (2/3) of the directors then still in office who either were
        directors on January 1, 1996 or whose appointment or election or
        nomination for election was previously so approved;

                                       8
<PAGE>

 (iii)  there is consummated a merger or consolidation of the Corporation (or
        any direct or indirect wholly-owned Subsidiary of the Corporation) with
        any other corporation, other than a merger or consolidation which would
        result in the Voting Securities of the Corporation outstanding
        immediately prior thereto continuing to represent (either by remaining
        outstanding or being converted into voting securities of the surviving
        entity or any parent thereof) more than 60% of the combined voting power
        of the Voting Securities of the Corporation (or the voting securities of
        such surviving entity or any parent thereof) outstanding immediately
        after such merger or consolidation (an "Excluded Transaction"); or

   (iv) the stockholders of the Corporation approve a plan of complete
        liquidation of the Corporation or there is consummated an agreement for
        the sale or disposition by the Corporation of all or substantially all
        of the Corporation's assets.

SECTION 13.  General Provisions.
             ------------------

(a) Income Tax Withholding.  The Corporation shall have the authority and the
    ----------------------
    right to deduct or withhold, or require a Participant to remit to the
    Corporation, an amount sufficient to satisfy federal, state, and local taxes
    (including the participant's FICA obligation) required by law to be withheld
    with respect to any taxable event arising as a result of the Plan. With
    respect to withholding required upon any taxable event under the Plan, the
    Committee may, at the time the Award is granted or thereafter, require or
    permit that any such withholding requirement be satisfied, in whole or in
    part, by withholding from the award shares of stock having a Fair Market
    Value on the date of withholding equal to the minimum amount (and not any
    greater amount) required to be withheld for tax purposes, all in accordance
    with such procedures as the Committee establishes.

(b) Nontransferability.  Unless so provided in the Agreement with respect to
    ------------------
    such Award, no Award shall be assignable or transferable, and no right or
    interest of any Participant shall be subject to any lien, obligation or
    liability of the Participant, except by will or the laws of descent and
    distribution.

(c) No Right to Employment.  No person shall have any claim or right to be
    ----------------------
    granted an Award, and the grant of an Award shall not be construed as giving
    a Participant the right to be retained in the employ of the Employer.
    Further, the Employer expressly reserves the right at any time to dismiss a
    Participant free from any liability, or any claim under the Plan, except as
    provided herein or in any agreement entered into with respect to an Award.

(d) No Rights as Stockholder.  Subject to the provisions of the applicable
    ------------------------
    Award, no Participant or transferee of an Option or Restricted Stock Unit
    shall have any rights as a stockholder with respect to any shares of Common
    Stock to be distributed under the Plan until he or she has become the holder
    thereof.  Notwithstanding the foregoing, in connection with each grant of
    Restricted Stock hereunder, the applicable Award shall specify if and to
    what extent the Participant shall not be entitled to the rights of a
    stockholder in respect of such Restricted Stock.

(e) Construction of the Plan.  The validity, construction, interpretation,
    ------------------------
    administration and effect of the Plan and of its rules and regulations, and
    rights relating to the Plan, shall be determined solely in accordance with
    the laws of the State of Delaware.

                                       9
<PAGE>

(f) Effective Date.  Subject to the approval of the stockholders of the
    --------------
    Corporation, the Plan shall be effective on March 8, 1996 (the "Effective
    Date").  No Options or Awards may be granted under the Plan after March 7,
    2006.

(g) Amendment of Plan.  The Board may amend, suspend or terminate the Plan or
    -----------------
    any portion thereof at any time.  The Chief Executive Officer shall be
    authorized to make minor or administrative modifications to the Plan as well
    as modifications to the Plan which may be dictated by requirements of
    federal or state statutes applicable to the Corporation or authorized or
    made desirable by such statutes.  No modification or termination of the Plan
    shall, without the optionee's consent, alter or impair any of his or her
    rights or obligations under any Award theretofore granted to him or her
    under the Plan.

(h) Amendment of Award. The Committee may amend, modify or terminate any
    ------------------
    outstanding Award with the Participant's consent at any time prior to
    payment or exercise in any manner not inconsistent with the terms of the
    Plan, including without limitation, (i) to change the date or dates as of
    which (A) an Option, Stock Appreciation Right or Limited Right becomes
    exercisable, or (B) shares of Restricted Stock, Restricted Stock Units or
    Performance Share Awards become nonforfeitable; or (ii) to cancel and
    reissue an Award under such different terms and conditions as it determines
    appropriate.

Hardship Distributions.  In no event shall any Option granted under this Plan be
----------------------
exercisable through payment of the Option Price in cash during the period of one
year following a hardship distribution under the UNUM Employees Retirement
Savings Plan and Trust, as defined therein.

Adjustments and Assumption.  In the event of a reorganization, recapitalization,
--------------------------
stock split, stock dividend, combination of shares, merger, consolidation,
distribution of assets, or any other change in the corporate structure or shares
of the Corporation, the Committee shall make such adjustments as it deems
appropriate in the number and kind of shares authorized by the Plan, in the
number and kind of shares or Performance Shares covered by the Awards granted,
in the maximum number of Options, Restricted Stock, Restricted Stock Units and
Performance Shares which may be granted to any individual Participant in a
single calendar year, and in the purchase price of outstanding Options.  In the
event of any merger, consolidation or other reorganization in which the
Corporation is not the surviving or continuing corporation, unless otherwise
provided for in the documents governing such merger, consolidation or other
reorganization, all Awards granted hereunder and outstanding on the date of such
event shall be assumed by the surviving or continuing corporation with
appropriate adjustment as to the number and kind of shares and purchase price of
the shares.

                                       10

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