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                                UNUM CORPORATION

                                       TO

                               MELLON BANK, N.A.,
                                        as Trustee


                                ________________


                          First Supplemental Indenture

                            Dated as of May __, 1995

                                       To

                                    Indenture

                            Dated as of May __, 1995
                                ________________



             ___% Junior Subordinated Deferrable Interest Debentures
                               Series A, Due 2025

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     FIRST SUPPLEMENTAL INDENTURE, dated as of May __, 1995, between UNUM
Corporation, a corporation duly organized and existing under the laws of the
State of Delaware (herein called the "Company"), having its principal office at
2211 Congress Street, Portland, Maine 04122, and Mellon Bank, N.A., a national
banking association, as Trustee (herein called the "Trustee") under the
Indenture dated as of May __, 1995 between the Company and the Trustee (the
"Indenture").


                             RECITALS OF THE COMPANY

     The Company has executed and delivered the Indenture to the Trustee to
provide for the issuance from time to time of its unsecured subordinated
debentures, notes or other evidences of indebtedness (the "Securities"), said
Securities to be issued in one or more series as in the Indenture provided.

     Pursuant to the terms of the Indenture, the Company desires to provide for
the establishment of a new series of its Securities to be known as its ___%
Junior Subordinated Deferrable Interest Debentures, Series A, Due 2025 (herein
called the "Series A Debentures"), the form and substance of such Series A
Debentures and the terms, provisions and conditions thereof to be set forth as
provided in the Indenture and this First Supplemental Indenture.

     All things necessary to make this First Supplemental Indenture a valid
agreement of the Company, and to make the Series A Debentures, when executed by
the Company and authenticated and delivered by the Trustee, the valid
obligations of the Company, have been done.

     NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH:

     For and in consideration of the premises and the purchase of the Series A
Debentures by the Holders thereof, and for the purpose of setting forth, as
provided in the Indenture, the form and substance of the Series A Debentures and
the terms, provisions and conditions thereof, it is mutually agreed, for the
equal and proportionate benefit of all Holders of the Series A Debentures, as
follows:


                                   ARTICLE ONE

                         GENERAL TERMS AND CONDITIONS OF
                             THE SERIES A DEBENTURES

     SECTION 101.  There shall be and is hereby authorized a series of
Securities designated the "___% Junior Subordinated Deferrable Interest
Debentures, Series A, Due 2025", limited in aggregate principal amount to
$230,000,000, which amount shall be as set forth in any written order of the
Company for the authentication and delivery of Series A Debentures. The Series A
Debentures shall mature and the principal shall be due and payable together with
all accrued and unpaid interest thereon on May __, 2025, and shall be issued in
the form of registered Series A Debentures without coupons, as set forth in
Article Four hereof.




     SECTION 102.  Except as provided in Section 106 herein, the Series A
Debentures shall be issued in certificated form. Principal of and interest (and
to the extent legally enforceable, interest on any overdue principal and on any
overdue instalment of interest) on the Series A Debentures issued in
certificated form will be payable, the transfer of such Series A Debentures will
be registrable and such Series A Debentures will be exchangeable for the Series
A Debentures bearing identical terms and provisions at the office or agency of
the Company in the Borough of Manhattan, The City and State of New York;
PROVIDED, HOWEVER, that payment of interest may be made at the option of the
Company by check mailed to the Person entitled thereto at such address as shall
appear in the Security Register.

     SECTION 103.  Each Series A Debenture will bear interest at the rate of
___% per annum from the original date of issuance until the principal thereof
becomes due and payable, and on any overdue principal and (to the extent that
payment of such interest is enforceable under applicable law) on any overdue
instalment of interest at the same rate per annum, payable monthly on the last
calendar day of each month (each, an "Interest Payment Date"), commencing on
May 31, 1995, to the person in whose name such Series A Debenture or any
predecessor Series A Debenture is registered, at the close of business on the
Business Day next preceding such Interest Payment Date. Any such interest not so
punctually paid or duly provided for shall forthwith cease to be payable to the
Holders on such Regular Record Date, and may be paid to the Person in whose name
the Series A Debenture (or one or more Predecessor Securities) is registered at
the close of business on a Special Record Date to be fixed by the Trustee for
the payment of such Defaulted Interest, notice whereof shall be given to the
Holders of the Series A Debentures not less than 10 days prior to such Special
Record Date, or may be paid at any time in any other lawful manner not
inconsistent with the requirements of any securities exchange on which the
Series A Debentures may be listed, and upon such notice as may be required by
such exchange, all as more fully provided in the Indenture.

     The amount of interest payable for any period will be computed on the basis
of a 360-day year of twelve 30-day months. Interest will accrue from the date of
original issuance to, but not including, the relevant payment date. In the event
that any date on which interest is payable on the Series A Debentures is not a
Business Day, then payment of interest payable on such date will be made on the
next succeeding day which is a Business Day (and without any interest or other
payment in respect of any such delay), except that, if such Business Day is in
the next succeeding calendar year, such payment shall be made on the immediately
preceding Business Day, in each case with the same force and effect as if made
on such date. A "Business Day" means each Monday, Tuesday, Wednesday, Thursday
and Friday which is not a day on which banking institutions in New York and any
other Place of Payment are authorized or obligated by law to close.

     SECTION 104.  The provisions of Section 1006 and 1007 of the Indenture
shall not apply with respect to the Series A Debentures.

     SECTION 105.  The Events of Default set forth in Sections 501(5) and the
Events of Default set forth in Sections 501(6) and 501(7) to the extent such
Events of Default relate to any Restricted Subsidiary shall not apply with
respect to the Series A Debentures.

                                       -2-



     SECTION 106.  The Series A Debentures shall be issuable in the form of one
or more Global Securities. The Depositary for the Series A Debentures shall be
The Depository Trust Company.

     SECTION 107.  The Series A Debentures shall be issuable only in registered
form without coupons in denominations of $25 and any integral multiple thereof.



                                   ARTICLE TWO

                      REDEMPTION OF THE SERIES A DEBENTURES

     SECTION 201. The Series A Debentures will be redeemable at the option of
the Company, as a whole or in part, at any time on or after May_____, 2000 and
prior to Maturity, upon not less than 30 nor more than 60 days' notice, at 100%
of the principal amount redeemed, together with accrued interest to the date
fixed for redemption.


                                  ARTICLE THREE

                      EXTENSION OF INTEREST PAYMENT PERIOD

     SECTION 301. The Company shall have the right, at any time during the term
of the Series A Debentures, from time to time to extend the interest payment
period of such Series A Debentures for up to 60 consecutive months (the
"Extension Period"), at the end of which period the Company shall pay all
interest accrued and unpaid thereon (together with interest thereon at the rate
specified for the Series A Debentures; PROVIDED that, during such Extension
Period, the Company shall not declare or pay any dividend on, or redeem,
purchase, acquire or make a liquidation payment with respect to, any of its
capital stock or make any guarantee payments with respect to the foregoing.
Prior to the termination of any such Extension Period, the Company may further
extend such Extension Period. Any Extension Period together, if extended, with
all such previous and further extensions thereof, (i) shall terminate on an
Interest Payment Date and (ii) shall not exceed 60 consecutive months or extend
beyond the Stated Maturity of the Series A Debentures. Upon the termination of
any Extension Period and upon the payment of all accrued and unpaid interest
then due, the Company may select a new Extension Period, subject to the
foregoing requirements. No interest during an Extension Period, except at the
end thereof, shall be due and payable.

     SECTION 302.  (a)  The Company shall give the Holders of the Series A
Debentures and the Trustee written notice of its selection of such Extension
Period not less than 10 Business Days prior to the earlier of (i) the next
succeeding Interest Payment Date or (ii) the date the Company is required to
give notice to Holders of the Series A Debentures (or, if applicable, to the New
York Stock Exchange or other applicable self-regulatory organization) of the
record or payment date of such interest payment, but in any event not less than
two business days prior to such record date.

                                       -3-



     (b)  The month in which any notice is given pursuant to paragraph (a) of
this Section shall constitute one of the 60 months which comprise the maximum
Extension Period.


                                  ARTICLE FOUR

                           FORM OF SERIES A DEBENTURE

     SECTION 401. The Series A Debentures and the Trustee's certificate of
authentication to be endorsed thereon are to be substantially in the following
forms:

                           (FORM OF FACE OF DEBENTURE)

No. ___________                                                   $_____________

CUSIP No.

                                UNUM CORPORATION

___% JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURE, SERIES A, DUE 2025

     UNUM Corporation, a corporation duly organized and existing under the laws
of the State of Delaware (herein referred to as the "Company", which term
includes any successor corporation under the Indenture hereunder referred to),
for value received, hereby promises to pay to _____________________________, or
registered assigns, the principal sum of _______________________ Dollars on May
31, 2025, and to pay interest on said principal sum from __________, 1995 or
from the most recent Interest Payment Date to which interest has been paid or
duly provided for, monthly on the last calendar day of each month, commencing
May 31, 1995 at the rate of ___% per annum until the principal hereof is paid or
made available for payment and at the rate of ...% per annum on any overdue
principal (including any overdue redemption payment) and on any overdue
instalment of interest. The amount of interest payable on any Interest Payment
Date shall be computed on the basis of a 360-day year of twelve 30-day months.
The interest so payable, and punctually paid or duly provided for, on any
Interest Payment Date will, as provided in said Indenture, be paid to the Person
in whose name this Security (or one or more Predecessor Securities) is
registered at the close of business on the Regular Record Date for such
interest, which shall be the close of business on the Business Day next
preceding such Interest Payment Date. Any such interest not so punctually paid
or duly provided for will forthwith cease to be payable to the Holder on such
Regular Record Date and may either be paid to the Person in whose name this
Security (or one or more Predecessor Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to
be fixed by the Trustee, notice whereof shall be given to Holders of Securities
of this series not less than 10 days prior to such Special Record Date, or be
paid at any time in any other lawful manner not inconsistent with the
requirements of any securities exchange on which the Securities of this series
may be listed, and upon such notice as may be required by such exchange, all as
more fully provided in said Indenture.

                                       -4-



     Payment of the principal of (and premium, if any) and interest (and, to the
extent that payment of such interest shall be legally enforceable, interest on
any overdue principal and on any overdue instalment of interest) on this
Security will be made at the office or agency of the Company maintained for that
purpose in the Borough of Manhattan, The City and State of New York, in such
coin or currency of the United States of America as at the time of payment is
legal tender for payment of public and private debts; PROVIDED, HOWEVER, that at
the option of the Company payment of interest may be made by check mailed to the
address of the Person entitled thereto as such address shall appear in the
Security Register.

     The Company shall have the right, at any time during the term of the
Securities, from time to time to extend the interest payment period of such
Securities to up to 60 consecutive months (the "Extension Period"), at the end
of which period the Company shall pay all interest then accrued and unpaid
(together with interest thereon at the rate specified for the Securities);
PROVIDED that, during such Extension Period the Company shall not declare or pay
any dividend on, or redeem, purchase, acquire or make a liquidation payment with
respect to, any of its capital stock or make any guarantee payments with respect
to the foregoing. Prior to the termination of any such Extension Period, the
Company may further extend such Extension Period. Any such Extension Period
together, if extended, with all such previous and further extensions thereof (i)
shall terminate on an Interest Payment Date and (ii) shall not exceed
60 consecutive months or extend beyond the Stated Maturity of the Security. At
the termination of any such Extension Period and upon the payment of all accrued
and unpaid interest and any additional amounts then due, the Company may select
a new Extension Period.

     Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

     Unless the certificate of authentication hereon has been executed by the
Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

     IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed under its corporate seal.

Dated:                        UNUM Corporation


                              By
                                ------------------------------------------------
Attest:


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                                       -5-



                     (FORM OF CERTIFICATE OF AUTHENTICATION)

                          CERTIFICATE OF AUTHENTICATION


     This is one of the Securities of the series designated therein referred to
in the within-mentioned Indenture.

                              Mellon Bank, N.A.,
                                   as Trustee


                              By
                                ------------------------------------------------
                                   Authorized Officer



                         (FORM OF REVERSE OF DEBENTURE)

     This Security is one of a duly authorized issue of securities of the
Company (herein called the "Securities"), issued and to be issued in one or more
series under an Indenture, dated as of May __, 1995 (herein called the
"Indenture", which term shall have the meaning assigned to it in such
instrument), between the Company and Mellon Bank, N.A., as Trustee (herein
called the "Trustee", which term includes any successor trustee under the
Indenture), as supplemented by the First Supplemental Indenture, dated as of May
__, 1995 between the Company and the Trustee (the "First Supplemental
Indenture"), and reference is hereby made to the Indenture as supplemented by
the First Supplemental Indenture for a statement of the respective rights,
limitations of rights, duties and immunities thereunder of the Company, the
Trustee, the holders of the Senior Indebtedness and the Holders of the
Securities and of the terms upon which the Securities are, and are to be,
authenticated and delivered. This Security is one of the series designated on
the face hereof, limited in aggregate principal amount to $230,000,000.

     The Securities of this series are subject to redemption upon not less than
30 days' notice by mail, at any time on or after __________, 2000, as a whole or
in part, at the election of the Company, at a Redemption Price equal to 100% of
the principal amount, together in the case of any such redemption with accrued
interest to the Redemption Date, but interest installments whose Stated Maturity
is on or prior to such Redemption Date will be payable to the Holders of such
Securities, or one or more Predecessor Securities, of record at the close of
business on the relevant Record Dates referred to on the face hereof, all as
provided in the Indenture.

     In the event of redemption of this Security in part only, a new Security or
Securities of this series and of like tenor for the unredeemed portion hereof
will be issued in the name of the Holder hereof upon the cancellation hereof.

     The indebtedness evidenced by this Security is, to the extent provided in
the Indenture and the First Supplemental Indenture, subordinated and subject in
right of payment to the prior payment in full of all Senior Indebtedness, and
this Security is issued subject to the provisions

                                       -6-


of the Indenture with respect thereto. Each Holder of this Security, by
accepting the same, (a) agrees to and shall be bound by such provisions,
(b) authorizes and directs the Trustee on his behalf to take such action as may
be necessary or appropriate to acknowledge or effectuate the subordination so
provided and (c) appoints the Trustee his attorney-in-fact for any and all such
purposes. Each Holder hereof, by his acceptance hereof, hereby waives all notice
of the acceptance of the subordination provisions contained herein and in the
Indenture by each holder of Senior Indebtedness, whether now outstanding or
hereafter incurred, and waives reliance by each such Holder upon said
provisions.

     The Indenture contains provisions for defeasance at any time of the entire
indebtedness of this Security upon compliance with certain conditions set forth
in the Indenture.

     If an Event of Default with respect to Securities of this series shall
occur and be continuing, the principal of the Securities of this series may be
declared due and payable in the manner and with the effect provided in the
Indenture as supplemented by the First Supplemental Indenture.

     The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with the
consent of the Holders of 66 2/3% in principal amount of the Securities at the
time Outstanding of each series to be affected. The Indenture also contains
provisions permitting the Holders of specified percentages in principal amount
of the Securities of each series at the time Outstanding, on behalf of the
Holders of all Securities of such series, to waive compliance by the Company
with certain provisions of the Indenture and certain past defaults under the
Indenture and their consequences. Any such consent or waiver by the Holder of
this Security shall be conclusive and binding upon such Holder and upon all
future Holders of this Security and of any Security issued upon the registration
of transfer hereof or in exchange herefor or in lieu hereof, whether or not
notation of such consent or waiver is made upon this Security.

     No reference herein to the Indenture or the First Supplemental Indenture
and no provision of this Security, the Indenture or the First Supplemental
Indenture shall alter or impair the obligation of the Company, which is absolute
and unconditional, to pay the principal of and any premium and interest on this
Security at the times, place and rate, and in the coin or currency, herein
prescribed.

     The Securities of this series are issuable only in registered form without
coupons in denominations of $25 and any integral multiple thereof. As provided
in the Indenture and subject to certain limitations therein set forth,
Securities of this series are exchangeable for a like aggregate principal amount
of Securities of this series and of like tenor of a different authorized
denomination, as requested by the Holder surrendering the same.

     No service charge shall be made for any such registration of transfer or
exchange, but the Company may require payment of a sum sufficient to cover any
tax or other governmental charge payable in connection therewith.

                                       -7-



     Prior to due presentment of this Security for registration of transfer, the
Company, the Trustee and any agent of the Company or the Trustee may treat the
Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

     All terms used in this Security which are defined in the Indenture shall
have the meanings assigned to them in the Indenture.


                                  ARTICLE FIVE

                      ORIGINAL ISSUE OF SERIES A DEBENTURES

     SECTION 501.  Series A Debentures in the aggregate principal amount of
$[   ,   ,   ], may, upon execution of this First Supplemental Indenture, or
from time to time thereafter, be executed by the Company and delivered to the
Trustee for authentication, and the Trustee shall thereupon authenticate and
deliver said Securities to or upon the written order of the Company, signed by
its Chairman, its President, or any Vice President and its Treasurer or an
Assistant Treasurer, its Secretary or an Assistant Secretary, without any
further action by the Company.


                                   ARTICLE SIX

                           PAYING AGENT AND REGISTRAR

     SECTION 601.  Mellon Bank, N.A. will be the initial Paying Agent and
Registrar for the Series A Debentures.


                                  ARTICLE SEVEN

                                SUNDRY PROVISIONS

     SECTION 701.  Except as otherwise expressly provided in this First
Supplemental Indenture or in the form of Series A Debenture or otherwise clearly
required by the context hereof or thereof, all terms used herein or in said form
of Series A Debenture that are defined in the Indenture shall have the several
meanings respectively assigned to them thereby.

     SECTION 702.  The Indenture, as supplemented by this First Supplemental
Indenture, is in all respects ratified and confirmed, except as modified by this
First Supplemental Indenture, and this First Supplemental Indenture shall be
deemed part of the Indenture in the manner and to the extent herein and therein
provided.

     SECTION 703.  This First Supplemental Indenture and the Series A Debentures
shall be governed by and construed in accordance with the laws of the State of
New York.

                                       -8-



     SECTION 704.  In case any provision of this First Supplemental Indenture or
in the Series A Debentures shall be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

     SECTION 705.  The Article and Section headings herein and the Table of
Contents are for convenience only and shall not affect the construction hereof.




                                 _______________

                                       -9-



     This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same instrument.

     IN WITNESS WHEREOF, the parties hereto have caused this First Supplemental
Indenture to be duly executed, and their respective corporate seals to be
hereunto affixed and attested, all as of the day and year first above written.


                              UNUM CORPORATION


                              By
                                ------------------------------------------------

Attest:        [Seal]



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                              MELLON BANK, N.A., as Trustee


                              By
                                ------------------------------------------------
                                   Assistant Vice President

Attest:        [Seal]
     Authorized Officer


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                                      -10-