Exhibit 4.2

TORCHMARK CORPORATION

as Issuer

and

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.

as Trustee

Fourth Supplemental Indenture

Dated as of September 24, 2012

3.80% Senior Notes due 2022

FOURTH SUPPLEMENTAL INDENTURE

FOURTH SUPPLEMENTAL INDENTURE, dated as of September 24, 2012 (this “ Fourth Supplemental Indenture ”) by and between Torchmark Corporation, a Delaware corporation (the “ Company ”) and The Bank of New York Mellon Trust Company, N.A., a national banking association (successor in interest to J.P. Morgan Trust Company, N.A), as trustee under the Indenture (defined below) (the “ Trustee ”).

WITNESSETH:

WHEREAS, the Company entered into that certain Indenture (the “ Base Indenture ” and, together with this Fourth Supplemental Indenture, the “ Indenture ”) dated as of February 1, 1987 with Morgan Guaranty Trust Company of New York, as trustee (“ Morgan Guaranty ”), providing for the issuance of Securities in series by the Company.

WHEREAS, the Company, Morgan Guaranty and The First National Bank of Chicago entered into that certain Instrument of Resignation, Appointment and Acceptance effective August 8, 1994, providing for the replacement of Morgan Guaranty as trustee under the Base Indenture with The First National Bank of Chicago.

WHEREAS, the Company, Bank One Trust Company, National Association (successor in interest to The First National Bank of Chicago) and The Bank of New York entered into that certain Supplemental Indenture dated December 14, 2001 (the “ First Supplemental Indenture ”), (i) creating and authorizing a series of Securities under the Base Indenture entitled “6  ¹ / ₄ % Senior Notes due 2006” (the “ 2006 Notes ”) and (ii) appointing The Bank of New York as an additional trustee pursuant to Section 901(6) of the Base Indenture with respect to the 2006 Notes.

WHEREAS, Bank One Trust Company, National Association transferred its corporate trust business to J.P. Morgan Trust Company, National Association effective November 15, 2003.

WHEREAS, the Company, The Bank of New York and The Bank of New York Trust Company, N.A. entered into an Agreement of Resignation, Appointment and Acceptance effective May 5, 2005, providing for the replacement of The Bank of New York as an additional trustee under the Indenture with The Bank of New York Trust Company, N.A.

WHEREAS, the Company, J.P. Morgan Trust Company, N.A. (successor in interest to Bank One Trust Company, National Association) and The Bank of New York Trust Company, N.A. entered into that certain Second Supplemental Indenture dated June 23, 2006 (the “ Second Supplemental Indenture ”), (i) creating and authorizing a series of Securities under the Base Indenture entitled “6.375% Senior Notes due 2016” (the “ 2016 Notes ”) and (ii) appointing The Bank of New York Trust Company, N.A. as an additional trustee pursuant to Section 901(6) of the Base Indenture with respect to the 2016 Notes.

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WHEREAS, The Bank of New York Trust Company, N.A. succeeded to the corporate trust business of J.P. Morgan Trust Company, N.A. effective October 1, 2006.

WHEREAS, the Trustee changed its name to The Bank of New York Mellon Trust Company, N.A. effective July 1, 2008.

WHEREAS, the Company and the Trustee entered into that certain Third Supplemental Indenture dated June 30, 2009 (the “ Third Supplemental Indenture ”), creating and authorizing a series of Securities under the Base Indenture entitled “9.25% Senior Notes due 2019.”

WHEREAS, Section 901(5) of the Base Indenture provides that a supplemental indenture may be entered into by the Company and the Trustee without the consent of any Holders to make provisions to establish the form or terms of Securities of any series as permitted by Sections 201 and 301 of the Base Indenture.

WHEREAS, the Company has furnished the Trustee with (i) an Opinion of Counsel stating that the execution of this Fourth Supplemental Indenture is authorized or permitted by the Base Indenture; (ii) an Officers’ Certificate stating that all conditions precedent under the Base Indenture for the execution of this Fourth Supplemental Indenture have been satisfied; and (iii) a Secretary’s Certificate certifying the resolutions of the Board of Directors of the Company authorizing this Fourth Supplemental Indenture.

WHEREAS, for its lawful purposes, the Company desires to create and authorize a series of Securities under the Base Indenture entitled “3.80% Senior Notes due 2022” (the “ Notes ”) in an initial aggregate principal amount of Three Hundred Million Dollars ($300,000,000) and, to provide the terms and conditions upon which the Notes are to be executed, registered, authenticated, issued and delivered, the Company has duly authorized the execution and delivery of this Fourth Supplemental Indenture setting forth the terms of the Notes.

WHEREAS, this Fourth Supplemental Indenture shall amend the Base Indenture and supersede the First Supplemental Indenture, the Second Supplemental Indenture and the Third Supplemental Indenture in their entirety but only with respect to the Notes; to the extent the terms of the Base Indenture are inconsistent with this Fourth Supplemental Indenture, the terms of this Fourth Supplemental Indenture shall govern.

WHEREAS, all acts and things necessary to make the Notes, when executed by the Company and authenticated and delivered hereunder and duly issued by the Company, the valid, binding and legal obligations of the Company, and to make this Fourth Supplemental Indenture a valid, binding and legal obligation of the Company, have been done and performed.

NOW, THEREFORE, in order to declare the terms and conditions upon which the Notes are executed, registered, authenticated, issued and delivered, and in consideration of the premises, of the purchase and acceptance of such Notes by the Holders thereof, the Company covenants and agrees with the Trustee, for the equal and proportionate benefit of the respective Holders from time to time of such Notes, as follows:

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ARTICLE 1

D EFINITIONS

Section 1.01 . Definitions . For all purposes of the Indenture, except as otherwise expressly provided or unless the context otherwise requires:

(i) the terms defined in this Article 1 have the meanings assigned to them in this Article and include the plural as well as the singular;

(ii) capitalized terms not defined herein have the meanings given in the Base Indenture;

(iii) all other terms used herein that are defined in the Trust Indenture Act, either directly or by reference therein, have the meanings assigned to them therein; and

(iv) the words “herein,” “hereof’ and “hereunder” and other words of similar import refer to this Fourth Supplemental Indenture as a whole and not to any particular Article, Section or other subdivision.

“ Agent Members ” has the meaning specified in Section 2.05.

“ Applicable Procedures ” means, with respect to any transfer or exchange of or for beneficial interest in a Global Note, the rules and procedures of the Depositary, Euroclear and Clearstream that apply to such transfer or exchange.

“ Clearstream ” means Clearstream Banking, société anonyme, Luxembourg (formerly Cedel Bank, société anonyme), and any successor thereto.

“ Comparable Treasury Issue ” means the United States Treasury security selected by a Reference Treasury Dealer as having an actual or interpolated maturity comparable to the remaining term of the Notes called for redemption, that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Notes called for redemption.

“ Comparable Treasury Price ” means, with respect to any Redemption Date, the average, as determined by the Company or such agent as may be appointed by the Company for this purpose, of the Reference Treasury Dealer Quotations for that Redemption Date.

“ Depositary ” means The Depository Trust Company until a successor Depositary shall have become such pursuant to the applicable provisions of the Indenture and thereafter “Depositary” shall mean such successor Depositary.

“ Euroclear ” means the Euroclear System and any successor thereto.

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“ Exchange Act ” means the U.S. Securities Exchange Act of 1934, as amended.

“ Global Note ” means a Note in global form registered in the Security Register in the name of a Depositary or a nominee thereof.

“ Physical Notes ” means permanent certificated Notes in registered form issued in denominations of $1,000 and integral multiples of $1,000 above that amount.

“ Principal Amount ” of a Note means the Principal Amount as set forth on the face of the Note.

“ Redemption Date ” shall mean the date specified for redemption of the Notes in accordance with the terms of the Notes and Section 3.01.

“ Redemption Price ” has the meaning specified in Section 3.01.

“ Reference Treasury Dealer ” means Merrill Lynch, Pierce, Fenner & Smith Incorporated, Wells Fargo Securities, LLC and one other U.S. Government securities dealer selected by the Company, and each of their respective successors.

“ Reference Treasury Dealer Quotations ” means, on any Redemption Date, the average, as determined by the Company or such agent as may be appointed by the Company for this purpose, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Company by each Reference Treasury Dealer at 3:30 p.m., New York City time, on the third Business Day preceding that Redemption Date.

“ Remaining Scheduled Payments ” means the remaining scheduled payments of principal of and interest on the Notes called for redemption that would be due after the related Redemption Date but for that redemption; provided that if a Redemption Date is not an Interest Payment Date, the amount of the next succeeding scheduled interest payment on the Notes will be reduced by the amount of interest accrued on the Notes to such Redemption Date.

“ Treasury Rate ” means, with respect to any Redemption Date, the rate per year equal to the semi-annual equivalent yield to maturity (computed as of the third Business Day immediately preceding that Redemption Date) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for that Redemption Date.

ARTICLE 2

T HE N OTES

Section 2.01 . Title and Terms . There is hereby created and authorized under the Base Indenture a series of Securities entitled “3.80% Senior Notes due 2022,” which shall be a series limited initially to $300,000,000 aggregate Principal Amount (except that the Company may, without the consent of Holders, reopen this series of Notes and issue additional Notes so as to

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increase the aggregate Principal Amount of Notes Outstanding in compliance with the procedures set forth in the Base Indenture, so long as any such additional Notes have the same tenor and terms (including, without limitation, rights to receive accrued and unpaid interest as the Notes then Outstanding); provided that no such additional Notes may be issued unless they are treated as part of the same “issue” as the Notes for U.S. federal income tax purposes; and further provided that the additional Notes have the same CUSIP number as the Notes). For all purposes of the Indenture, the term “Notes” shall include the Notes initially issued on the date of original issuance of the Notes and any other Notes issued after such date under the Indenture. For purposes of the Indenture, all Notes shall vote together and otherwise constitute a single series of Securities.

The Notes shall rank equally and pari passu with all other unsecured and unsubordinated indebtedness of the Company.

Section 2.02 . Forms of Notes . The Notes shall be substantially in the form set forth in Exhibit A hereto with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by the Indenture, and with such letters, numbers or other marks of identification and such legends or endorsements placed thereon as may be required to comply with the rules of any securities exchange or Depositary therefor, the Internal Revenue Code of 1986, as amended, and the regulations thereunder, or as may, consistently herewith, be determined by the officers executing such Notes, as evidenced by their execution thereof.

The terms and provisions contained in the form of Notes attached hereto as Exhibit A shall constitute, and are hereby expressly made, a part of this Fourth Supplemental Indenture and the Company and the Trustee, by their execution and delivery of this Fourth Supplemental Indenture, expressly agree to such terms and provisions and to be bound thereby.

The Notes shall initially be issued in the form of a permanent Global Note in registered form. The aggregate Principal Amount of the Global Note may from time to time be increased or decreased by adjustments made on the records of the Trustee, as custodian for the Depositary, as hereinafter provided.

Section 2.03. Denominations. The Notes shall be issuable only in registered form without coupons and in denominations of $1,000 and integral multiples of $1,000 above that amount.

Section 2.04. Registration of Transfer and Exchange. The Company shall cause to be kept at the Corporate Trust Office of the Trustee a register (the register maintained in such office and in any other office or agency designated pursuant to Section 1002 of the Base Indenture being herein sometimes collectively referred to as the “ Security Register ”) in which, subject to such reasonable regulations as it may prescribe, the Company shall provide for the registration of Notes and of transfers of Notes. The Trustee is hereby appointed “Security Registrar” (the “ Security Registrar ”) for the purpose of registering Notes and transfers of Notes as herein provided.

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Upon surrender for registration of transfer of any Note at an office or agency of the Company designated pursuant to Section 1002 of the Base Indenture for such purpose, the Company shall execute, and the Trustee shall authenticate and deliver, in the name of the designated transferee or transferees, one or more new Notes of any authorized denominations and of a like aggregate principal amount and tenor.

At the option of the Holder and subject to the other provisions of this Section 2.04 and Section 2.05 hereof and Section 309 of the Base Indenture, Notes may be exchanged for other Notes of any authorized denominations and of a like aggregate principal amount and tenor, upon surrender of the Notes to be exchanged at such office or agency. Whenever any Notes are so surrendered for exchange, the Company shall execute, and the Trustee shall authenticate and deliver, the Notes which the Holder making the exchange is entitled to receive.

All Notes issued upon any registration of transfer or exchange of Notes shall be the valid obligations of the Company, evidencing the same debt, and entitled to the same benefits under the Indenture, as the Notes surrendered upon such registration of transfer or exchange.

Every Note presented or surrendered for registration of transfer or for exchange shall (if so required by the Company or the Trustee) be duly endorsed, or be accompanied by a written instrument of transfer in form satisfactory to the Company and the Note Registrar duly executed, by the Holder thereof or his attorney duly authorized in writing.

No service charge shall be made for any registration of transfer or exchange of Notes, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection with any registration of transfer or exchange of Notes, other than exchanges pursuant to Section 304 of the Base Indenture not involving any transfer.

If the Company elects to redeem Notes, it shall not be required to (i) issue, register the transfer of or exchange any Note during the period beginning at the opening of business 15 days before the day the Company mails the notice of redemption and ending at the close of business on the day such notice of redemption is mailed or (ii) register the transfer or exchange of any Note after a notice of redemption has been given to Holders except, where such notice provides that such Note is to be redeemed only in part, the Company shall be required to exchange or register a transfer of the portion thereof not to be redeemed.

Neither the Trustee nor any of its agents shall (i) have any duty to monitor compliance with or with respect to any federal or state or other securities or tax laws or (ii) have any duty to obtain documentation relating to any transfers or exchanges other than as specifically required hereunder.

As used in this Section, the term “ transfer ” encompasses any sale, pledge, transfer or other disposition of any Note.

Section 2.05. Book-Entry Provisions for a Global Note. (a) The Global Note initially shall be registered in the name of the Depositary or the nominee of such Depositary and be delivered to the Trustee as custodian for the Depositary.

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Investors may hold their interests in the Global Note directly through the Depositary, Euroclear or Clearstream, if they are members of or participants in such systems (“ Agent Members ”), or indirectly through organizations that are Agent Members in such systems. If interests in the Global Note are held through Euroclear or Clearstream, Euroclear and Clearstream shall hold such interests in the Global Note through the Depositary on behalf of their Agent Members.

Agent Members of the Depositary, Euroclear or Clearstream shall have no rights under the Indenture with respect to any Global Note held on their behalf by the Depositary, or the Trustee as its custodian, or under the Global Note, and the Depositary may be treated by the Company, the Trustee and any agent of the Company or the Trustee as the absolute owner of the Global Note for all purposes whatsoever. Notwithstanding the foregoing, nothing herein shall prevent the Company, the Trustee or any agent of the Company or the Trustee from giving effect to any written certification, proxy or other authorization furnished by the Depositary or impair, as between the Depositary and its Agent Members, the operation of customary practices governing the exercise of the rights of any Holder.

(b) Transfers of the Global Note shall be limited to transfers in whole, but not in part, to the Depositary, its successors or their respective nominees. Interests of beneficial owners in a Global Note may be transferred or exchanged, in whole or in part, for Physical Notes in accordance with the rules and procedures of the Depositary and the provisions of Section 309 of the Base Indenture. In addition, Physical Notes shall be transferred to all beneficial owners in exchange for their beneficial interests in the Global Note if (a) such Depositary has notified the Company (or the Company becomes aware) that the Depositary (i) is unwilling or unable to continue as Depositary for such Global Note or (ii) has ceased to be a clearing agency registered under the Exchange Act when the Depositary is required to be so registered to act as such Depositary and, in either such case, no successor Depositary shall have been appointed within 90 days of such notification or of the Company becoming aware of such event; (b) there shall have occurred and be continuing an Event of Default with respect to such Global Note; or (c) the Company, at its option, elects to terminate the book-entry system through the Depositary.

(c) In connection with any transfer or exchange of a portion of the beneficial interest in the Global Note to beneficial owners pursuant to paragraph (b) above, the Security Registrar shall (if one or more Physical Notes are to be issued) reflect on its books and records the date and a decrease in the Principal Amount of the Global Note in an amount equal to the Principal Amount of the beneficial interest in the Global Note to be transferred, and the Company shall execute, and the Trustee shall authenticate and deliver, one or more Physical Notes of like tenor and amount.

(d) In connection with the transfer of the entire Global Note to beneficial owners pursuant to paragraph (b) above, the Global Note shall be deemed to be surrendered to the Trustee for cancellation, and the Company shall execute, and the Trustee shall authenticate and deliver, to each beneficial owner identified by the Depositary in exchange for its beneficial interest in the Global Note, an equal aggregate Principal Amount of Physical Notes of authorized denominations and the same tenor.

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(e) The Holder of the Global Note may grant proxies and otherwise authorize any Person, including Agent Members and Persons that may hold interests through Agent Members, to take any action which a Holder is entitled to take under the Indenture or the Notes.

(f) None of the Company, the Trustee, any Paying Agent or any Security Registrar will have any responsibility or liability for any aspect of Depositary records relating to, or payments made on account of, beneficial ownership interests in a Global Note or for maintaining, supervising or reviewing any Depositary records relating to such beneficial ownership interests, or for transfers of beneficial interests in the Notes or any transactions between the Depositary and beneficial owners.

Section 2.05. Euroclear and Clearstream Procedures Applicable . The provisions of the “Operating Procedures of the Euroclear System” and “Terms and Conditions Governing Use of Euroclear” and the “General Terms and Conditions” and “Customer Handbook” of Clearstream shall be applicable to transfers of beneficial interests in any Global Note held by Agent Members through Euroclear and Clearstream.

ARTICLE 3

R EDEMPTION

Section 3.01 . Optional Redemption of Notes by the Company. The Notes will not be redeemable at the option of any Holder thereof, upon the occurrence of any particular event or otherwise. The Notes will be redeemable, in whole or in part, at the option of the Company, at any time or from time to time, at a Redemption Price equal to the greater of (a) 100% of the principal amount of the Notes to be redeemed and (b) the sum of the present values of the Remaining Scheduled Payments on such Notes discounted to the Redemption Date, on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at a rate equal to the sum of the applicable Treasury Rate plus 30 basis points (the “ Redemption Price ”). The Redemption Price will be provided to the Trustee by the Company.

The Company shall give notice to the Trustee of its election to redeem Notes by a Company Order, at least 30 days but not more than 60 days before the Redemption Date (unless a shorter notice shall be satisfactory to the Trustee).

Section 3.02 . Selection of Notes to be Redeemed. If less than all the Notes are to be redeemed, the Trustee shall select the Notes to be redeemed in accordance with the procedures of the Depositary. The Trustee shall make the selection within 7 days from its receipt of the notice from the Company delivered pursuant to the second paragraph of Section 3.01 from Outstanding Notes not previously called for redemption.

Notes, or portions thereof selected by the Trustee for redemption, shall be in denominations of $1,000 and integral multiples of $1,000 above that amount. Provisions of the Indenture that apply to Notes called for redemption in whole also apply to Notes called for redemption in part. The Trustee shall notify the Company promptly of the Notes or portions of Notes to be redeemed.

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Section 3.03 . Notice of Redemption. At least 30 days but not more than 60 days before a Redemption Date, the Company shall deliver a notice of redemption to each Holder of Notes to be redeemed. The notice shall identify the Notes to be redeemed and shall state:

(i) the aggregate principal amount of Notes to be redeemed;

(ii) the Redemption Date;

(iii) the amount of interest accrued to the Redemption Date on the Notes to be redeemed;

(iv) that on and after the Redemption Date, interest on the Notes to be redeemed, or on the portion thereof to be redeemed, will cease to accrue;

(v) the name and address of the Paying Agent;

(vi) that Notes called for redemption must be surrendered to the Paying Agent for cancellation to collect the Redemption Price;

(vii) if fewer than all the outstanding Notes are to be redeemed, the certificate number (if such Notes are held other than in global form) and principal amounts of the particular Notes to be redeemed; and

(viii) the CUSIP number of the Notes being redeemed.

At the Company’s written request delivered at least 30 days prior to the date such notice is to be given (unless a shorter time period shall be acceptable to the Trustee), the Trustee shall give the notice of redemption in the Company’s name and at the Company’s expense.

Section 3.04 . Effect of Notice of Redemption. Once notice of redemption is given, Notes called for redemption become due and payable on the Redemption Date and at the Redemption Price stated in the notice. Upon surrender to the Paying Agent, such Notes shall be paid at the Redemption Price stated in the notice. Unless the Company Defaults on the payment of the Redemption Price, interest will cease to accrue on the Notes or portions thereof called for redemption.

Section 3.05 . Deposit of Redemption Price. Prior to 11:00 a.m. (New York City time) on a Redemption Date, the Company shall deposit with the Paying Agent (or if the Company or a Subsidiary or an Affiliate of either of them is the Paying Agent, shall segregate and hold in trust) money sufficient to pay the Redemption Price of all Notes to be redeemed on that date other than Notes or portions of Notes called for redemption which on or prior thereto have been delivered by the Company to the Trustee for cancellation.

Section 3.06 . Notes Redeemed in Part. Upon surrender of a Note that is redeemed in part, the Company shall execute and the Trustee shall authenticate and deliver to the Holder a new Note in an authorized denomination equal in principal amount to the unredeemed portion of the Note surrendered.

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ARTICLE 4

R EMEDIES

Section 4.01. Events of Default . In addition to the Events of Default set forth in Article Five of the Base Indenture, the following shall be an Event of Default with respect to the Notes:

(a) failure to pay principal or premium, if any, on any Note called for redemption on a Redemption Date.

ARTICLE 5

C OVENANTS

Section 5.01. Definition of Designated Subsidiaries . For purposes of Article Ten of the Base Indenture, “ Designated Subsidiary ” means each of Liberty National Life Insurance Company, United American Insurance Company, Globe Life And Accident Insurance Company and American Income Life Insurance Company, so long as it remains a Subsidiary, or any Subsidiary that is a successor of such Designated Subsidiary, as well as any other Subsidiary of the Company that would be deemed a Significant Subsidiary as such term is defined in Regulation S-X promulgated by the Commission.

ARTICLE 6

M ISCELLANEOUS P ROVISIONS

Section 6.01 . Trust Indenture Act. This Fourth Supplemental Indenture is hereby made subject to, and shall be governed by, the provisions of the Trust Indenture Act required to be part of and to govern indentures qualified under the Trust Indenture Act. If any provision hereof limits, qualifies or conflicts with another provision hereof which is required to be included in an indenture qualified under the Trust Indenture Act, such required provision shall control.

Section 6.02 . Effect of Headings and Table of Contents. The Article and Section headings herein are for convenience only and shall not affect the construction hereof, and all Article and Section references are to Articles and Sections, respectively, of this Fourth Supplemental Indenture unless otherwise expressly stated.

Section 6.03 . Successors and Assigns . All covenants and agreements in this Fourth Supplemental Indenture by the Company shall bind its successors and assigns, whether so expressed or not.

Section 6.04 . Severability Clause. In case any provision in this Fourth Supplemental Indenture or in the Notes 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 6.05 . Benefits of Fourth Supplemental Indenture. Nothing in this Fourth Supplemental Indenture or in the Notes, express or implied, shall give to any Person, other than the parties hereto and their respective successors hereunder and the Holders of Notes, any benefit or any legal or equitable right, remedy or claim under this Fourth Supplemental Indenture.

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Section 6.06 . Governing Law. This Fourth Supplemental Indenture and the Notes shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflicts of laws rules of such state.

Section 6.07. Counterparts . This Fourth Supplemental Indenture 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.

Section 6.08. Not Responsible for Recitals or Use of Proceeds from the Issuance of the Notes . The recitals contained herein (excluding the fifth, sixth, seventh, eighth and ninth recitals) shall be taken as the statements of the Company, and the Trustee assumes no responsibility for their correctness. Except for the Trustee’s certificate of authentication on the Notes, the Trustee makes no representations as to the validity or sufficiency of this Fourth Supplemental Indenture or of the Notes. The Trustee shall not be accountable for the use or application by the Company of the proceeds from the issuance of the Notes.

Section 6.09. Waiver of Jury Trial . EACH OF THE COMPANY AND THE TRUSTEE HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS INDENTURE, THE SECURITIES OR THE TRANSACTION CONTEMPLATED HEREBY.

Section 6.10. Force Majeure . In no event shall the Trustee be responsible or liable for any failure or delay in the performance of its obligations hereunder arising out of or caused by, directly or indirectly, forces beyond its control, including, without limitation, strikes, work stoppages, accidents, acts of war or terrorism, civil or military disturbances, nuclear or natural catastrophes or acts of God, and interruptions, loss or malfunctions of utilities, communications or computer (software and hardware) services; it being understood that the Trustee shall use reasonable efforts which are consistent with accepted practices in the banking industry to resume performance as soon as practicable under the circumstances.

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IN WITNESS WHEREOF, the Company has caused this Fourth Supplemental Indenture to be signed and delivered, and the Trustee has caused this Fourth Supplemental Indenture to be signed and delivered, all as of the day and year first written above.

[Signature Page to Fourth Supplemental Indenture]

EXHIBIT A

[FORM OF FACE OF NOTE]

THIS NOTE IS A GLOBAL NOTE WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE THEREOF. THIS NOTE MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A NOTE REGISTERED, AND NO TRANSFER OF THIS NOTE IN WHOLE OR IN PART MAY BE REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITARY OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (“DTC”), A NEW YORK CORPORATION, TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL IN AS MUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

TORCHMARK CORPORATION

3.80% Senior Notes due 2022

TORCHMARK CORPORATION, a corporation duly organized and existing under the laws of the State of Delaware (herein called the “ Company ,” which term includes any successor corporation under the Indenture hereinafter referred to on the reverse hereof), for value received, promises to pay to CEDE & CO., or its registered assigns, the principal sum of THREE HUNDRED MILLION DOLLARS ($300,000,000) or such other amount as indicated on the Schedule of Increases and Decreases attached hereto on September 15, 2022.

A-1

Interest Rate: 3.80% per year

Interest Payment Dates: March 15 and September 15 of each year, commencing March 15, 2013

Record Dates: March 1 and September 1

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

A-2

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

A-3

This is one of the 3.80% Senior Notes due 2022 referred to in the within-mentioned Indenture.

Dated: September 24, 2012

A-4

[FORM OF REVERSE OF NOTE]

TORCHMARK CORPORATION

3.80% Senior Notes due 2022

Indenture; Defined Terms . This Note is one of the 3.80% Senior Notes Due 2022 of the Company issued under an Indenture dated February 1, 1987 (the “ Base Indenture ”), between the Company and J.P. Morgan Trust Company, National Association, as supplemented by the Fourth Supplemental Indenture dated September 24, 2012 (the “ Fourth Supplemental Indenture ” and, together with the Base Indenture, the “ Indenture ”) between the Company and The Bank of New York Mellon Trust Company, N.A. (ultimate successor-in-interest to Morgan Guaranty Trust Company of New York, the “ Trustee ”).

Unless otherwise defined herein, capitalized terms herein are used as defined in the Indenture. The terms of the Notes include those stated in the Indenture and those made part thereof by reference to the Trust Indenture Act of 1939 (15 U.S.C. Sections 77aaa-77bbbb) (the “ Trust Indenture Act ”), as in effect on the date hereof. Notwithstanding anything to the contrary herein, the Notes are subject to all such terms, and holders of Notes are referred to the Indenture and the Trust Indenture Act for a statement of such terms. To the extent the terms of the Indenture, the Fourth Supplemental Indenture and this Note are inconsistent, the terms of the Fourth Supplemental Indenture shall govern.

Interest . The Company promises to pay cash interest on the Principal Amount of the Notes at the rate per year described above. Interest on the Notes will accrue from September 24, 2012, or from the most recent Interest Payment Date to which interest has been paid or duly provided for, to but excluding the next Interest Payment Date. The Company will pay interest semi-annually in arrears on each Interest Payment Date, commencing March 15, 2013, to the Person in whose name the Notes are registered at the close of business on the immediately preceding Record Date. Interest payable upon redemption will be paid to the Person to whom principal is paid. Interest will be computed on the basis of a 360-day year of twelve 30-day months.

If an Interest Payment Date, the Stated Maturity or a Redemption Date for the Notes falls on a day that is not a Business Day, the interest payment shall be postponed to the next succeeding Business Day, and no interest on such payment shall accrue for the period from and after such Interest Payment Date, the Stated Maturity or a Redemption Date.

If a Holder of at least $2,000,000 principal amount of Notes has given wire transfer instructions to the Company no later than 15 days immediately preceding the relevant due date for payment (or such date as the Trustee may

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accept in its discretion), the Company will pay, or cause to be paid by the Paying Agent, all principal and interest on the Holder’s Notes in accordance with those instructions. Other payments on the Notes will be made to the Holders at their address set forth in the Security Register.

Redemption of Notes at the Option of the Company . The Notes are redeemable, in whole or in part, at the option of the Company, at any time or from time to time, at a redemption price equal to the greater of (a) 100% of the principal amount to be redeemed and (b) the sum of the present values of the Remaining Scheduled Payments on such Notes discounted to the Redemption Date, on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at a rate equal to the sum of the applicable Treasury Rate plus 30 basis points (the “ Redemption Price ”) upon delivery of the Notes to the Paying Agent by the Holder as set forth in the Indenture. The Redemption Price will be paid in cash.

Notice of any redemption will be mailed at least 30 days but not more than 60 days before the Redemption Date to each Holder of the Notes to be redeemed. Unless the Company defaults in payment of the Redemption Price, on and after the Redemption Date, interest will cease to accrue on the Notes or portions thereof called for redemption. If less than all of the Notes are to be redeemed, the Notes to be redeemed shall be selected pro rata or by lot or by any other method the Trustee considers fair and appropriate.

The Notes are not subject to any sinking fund.

Paying Agent . Initially, The Bank of New York Mellon Trust Company, N.A. will act as Paying Agent. The Company may change any paying agent without notice to the Holders.

Covenants . The Indenture contains certain restrictive covenants and provisions for defeasance at any time of (a) the entire indebtedness evidenced by the Notes and (b) such restrictive covenants, in each case upon compliance by the Company with certain conditions set forth therein, which covenants and provisions apply to the Notes.

Events of Default . If an Event of Default with respect to the Notes shall occur and be continuing, the principal of the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

Amendment; Supplement; Waiver . 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 Notes at any time by the Company and the Trustee with the consent of the Holders of 66  ² / ₃ % in aggregate principal amount of Notes at the time Outstanding. The Indenture also contains provisions permitting the Holders of specified percentages

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in aggregate principal amount of Notes at the time Outstanding, on behalf of the Holders of the Notes, 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 Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Note issued upon the registration of transfer hereof or in exchange thereof of in lieu hereof, whether or not notation of such consent or waiver is made upon this Note.

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

Persons Deemed Owners . The registered Holder of this Note may be treated as the owner of this Note for all purposes.

Denominations; Transfer and Exchange . The Notes are in registered form without coupons in denominations of $1,000 and integral multiples of $1,000 above that amount. A Holder may transfer or exchange Notes in accordance with the Indenture. The Security Registrar may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay to it any taxes and required by law or permitted by the Indenture. The Registrar shall not be required to exchange or register a transfer of any Note for a period of 15 days immediately preceding a Redemption Date.

Authentication . This Note shall not be valid until the Trustee signs the certificate of authentication on the front hereof.

Governing Law . This Note shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflicts of laws rules of such state.

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FORM OF ASSIGNMENT

For value received,                                                                                                                                                             hereby assigns or transfers unto

The within Note, and hereby irrevocably constitutes and appoints                                                                                                                    attorney to transfer said Note on the books of the Company, with full power of substitution in the premises.

Dated:                     

NOTICE: The signature on this Assignment must correspond with the name as written upon the face of the Note in every particular without alteration or enlargement or any change whatever.

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Exhibit 4.5

FIRST SUPPLEMENTAL INDENTURE

DATED AS OF SEPTEMBER 24, 2012

BETWEEN

TORCHMARK CORPORATION,

AS ISSUER

AND

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,

AS TRUSTEE

TABLE OF CONTENTS

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FIRST SUPPLEMENTAL INDENTURE, dated as of September 24, 2012 (this “ Supplemental Indenture ”), between Torchmark Corporation, a Delaware corporation, as issuer (the “ Company ”), and The Bank of New York Mellon Trust Company, N.A., a national banking association incorporated and existing under the laws of the United States of America, (successor in interest to The Bank of New York), as trustee (the “ Trustee ”), supplementing the Junior Subordinated Indenture, dated as of November 2, 2001 (the “ Base Indenture ”), between the Company and The Bank of New York, as trustee.

RECITALS

WHEREAS, the Company executed and delivered the Base Indenture to the Trustee to provide for the future issuance of the Company’s unsecured junior subordinated debentures, notes or other evidence of indebtedness (the “ Securities ”), to be issued from time to time in one or more series as might be determined by the Company under the Base Indenture;

WHEREAS, Section 8.1 of the Base Indenture provides that the Company and the Trustee may, without the consent of any Holders, enter into a supplemental indenture to establish the forms or terms of the Securities of any series as provided in Sections 2.1 and 2.3 thereof;

WHEREAS, pursuant to Sections 2.1 and 2.3 of the Base Indenture and this Supplemental Indenture (together, the “ Indenture ”), the Company desires to provide for the establishment of a new series of its Securities to be known as its 5.875% Junior Subordinated Debentures due 2052 (the “ Debentures ”), with the form and terms thereof as hereinafter set forth; and

WHEREAS, the Company has requested that the Trustee execute and deliver this Supplemental Indenture, and all requirements necessary to make this Supplemental Indenture a valid instrument in accordance with its terms, and to make the Debentures, when executed by the Company and authenticated and delivered by the Trustee, the valid obligations of the Company, have been done and performed, and the execution and delivery of this Supplemental Indenture have been duly authorized in all respects.

NOW, THEREFORE, in consideration of the premises and the purchase and acceptance of the Debentures by the Holders thereof, and for the purpose of setting forth, as provided in the Indenture, the form and substance of the Debentures and the terms, provisions and conditions thereof, the Company covenants and agrees with the Trustee as follows:

ARTICLE 1

DEFINITIONS

Section 1.01. Definitions.

For all purposes of this Supplemental Indenture, except as otherwise expressly provided or unless the context otherwise requires:

(a) a term not defined herein that is defined in the Base Indenture has the same meaning when used in this Supplemental Indenture;

(b) the definition of any term in this Supplemental Indenture that is also defined in the Base Indenture shall supersede the definition of such term in the Base Indenture;

(c) a term defined anywhere in this Supplemental Indenture has the same meaning throughout;

(d) the singular includes the plural and vice versa;

(e) the words “herein,” “hereof” and “hereunder” and other words of similar import refer to this Supplemental Indenture as a whole and not to any particular Article, Section or other subdivision, and any reference to an Article, Section or other subdivision refers to an Article, Section or other subdivision of this Supplemental Indenture;

(f) headings are for convenience of reference only and do not affect interpretation; and

(g) the following terms have the meanings given to them in this Section 1.1(g):

“ Bankruptcy Law ” means Title 11, U.S. Code, or any similar federal or state bankruptcy, insolvency, reorganization or other law for the relief of debtors.

“ Base Indenture ” has the meaning specified in the introduction to this Supplemental Indenture.

“ Business Day ” means any day which is not a Saturday, a Sunday, a legal holiday or a day on which banking institutions or trust companies located in New York City are authorized or obligated by law to close.

“ Common Stock ” means shares of common stock of the Company, including treasury shares and shares sold pursuant to the Company’s dividend reinvestment plans and employee benefit plans.

“ Company ” has the meaning specified in the introduction to this Supplemental Indenture.

“ Compounded Interest ” means accrued and unpaid interest on the Debentures, together with interest thereon, to the extent permitted by applicable law, compounded quarterly at the Coupon Rate.

“ Coupon Rate ” has the meaning specified in Section 2.04(a) hereof.

“ Custodian ” means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

“ Debentures ” has the meaning specified in the Recitals of this Supplemental Indenture.

“ Deferral Period ” means the period commencing on an Interest Payment Date with respect to which the Company elects or is deemed to elect to defer interest pursuant to Section 2.05 and ending on the earlier of (i) the fifth anniversary of that Interest Payment Date and (ii) the next Interest Payment Date on which the Company has paid all deferred and unpaid amounts (including Compounded Interest) and all other accrued interest on the Debentures.

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“ Depositary ”, with respect to the Debentures, means The Depository Trust Company or any successor clearing agency.

“ Event of Default ” has the meaning specified in Section 2.06 hereof.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended, including the rules and regulations of the Securities and Exchange Commission promulgated thereunder.

“ Global Security ” means a Security in the form prescribed in Section 2.03 hereof and Exhibit A hereto evidencing all or part of the Debentures registered in the name of the Depositary or its nominee for such series.

“ Indenture ” has the meaning specified in the Recitals of this Supplemental Indenture.

“ Interest Payment Date ” means each March 15, June 15, September 15 and December 15, commencing December 15, 2012; provided that, if any such day is not a Business Day, then the Interest Payment Date shall be the immediately succeeding Business Day.

“ Interest Payment Period ” means the quarterly period from and including an Interest Payment Date to but not including the next succeeding Interest Payment Date, except for the first Interest Payment Period which shall be the period from and including the date of initial issuance of the Debentures (subject to Section 2.01(b) hereof) to but excluding December 15, 2012.

“ Maturity Date ” has the meaning specified in Section 2.02 hereof.

“ NRSRO ” means a nationally recognized statistical rating organization within the meaning of Section 3(a)(62) of the Exchange Act.

“ Parity Securities ” shall have the meaning specified in Section 3.01(b) hereof.

“ Paying Agent ” means any Person authorized by the Company to pay the principal of or interest and any other payments on the Debentures on behalf of the Company.

“ Predecessor Security ” of any particular Security means every previous Security evidencing all or a portion of the same debt as that evidenced by such particular Security; and, for the purposes of this definition, any Security authenticated and delivered under Section 2.9 of the Base Indenture in exchange for or in lieu of a mutilated, defaced, destroyed, lost or stolen Security shall be deemed to evidence the same debt as the mutilated, defaced, destroyed, lost or stolen Security.

“ Redemption Date ,” when used with respect to any Security to be redeemed, means the date fixed for such redemption by or pursuant to this Supplemental Indenture.

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“ Regular Record Date ” means, with respect to an Interest Payment Date, the March 1, June 1, September 1 and December 1, as the case may be, next preceding such Interest Payment Date, in each case whether or not a Business Day.

“ Securities ” has the meaning specified in the Recitals of this Supplemental Indenture.

“ Security Registrar ” means, with respect to the Debentures, The Bank of New York Mellon Trust Company, N.A., or any other firm appointed by the Company, acting as security registrar for the Debentures.

“ Security Registrar Office ” means the office of the applicable Security Registrar at which at any particular time its corporate agency business shall principally be administered, which office at the date hereof in the case of The Bank of New York Mellon Trust Company, N.A., in its capacity as Security Registrar under the Indenture, is located at 2 North LaSalle Street, Suite 1020, Chicago, Illinois 60602.

“ Subsidiary ” means, at any time, any Person the shares of stock or other ownership interests of which ordinarily have voting power to elect a majority of the board of directors or other managers of such Person, are at the time owned or the management and policies of which are otherwise at the time controlled, directly or indirectly through one or more intermediaries (including other Subsidiaries) or both, by another Person.

“ Supplemental Indenture ” has the meaning specified in the introduction to this Supplemental Indenture.

“ Tax Event ” means the receipt by the Company of an opinion of counsel, rendered by a law firm of nationally recognized standing that is experienced in such matters, stating that, as a result of any: (i) amendment to, or change in, (including any promulgation, enactment, execution or modification of) the laws (or any regulations under those laws) of the United States or any political subdivision thereof or therein affecting taxation, (ii) official administrative pronouncement (including a private letter ruling, technical advice memorandum or similar pronouncement) or judicial decision or administrative action or other official pronouncement interpreting or applying the laws or regulations enumerated in clause (i) above, by any court, government agency or regulatory authority, or (iii) threatened challenge asserted in connection with an audit of the Company or any of its Subsidiaries, or a threatened challenge asserted in writing against any taxpayer that has raised capital through the issuance of securities that are substantially similar to the Debentures, which amendment or change is enacted or effective or which pronouncement or decision is announced or which challenge is asserted against the Company or becomes publicly known on or after the date hereof, there is more than an insubstantial increase in the risk that interest accruable or payable by the Company on the Debentures is not, or will not be, deductible by the Company, in whole or in part, for United States federal income tax purposes.

“ Total Assets ” means, at any date, the total assets appearing on the most recently prepared consolidated balance sheet of the Company and its consolidated Subsidiaries as at the end of a fiscal quarter of the Company, prepared in accordance with generally accepted accounting principles.

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“ Underwriting Agreement ” means that certain Underwriting Agreement, dated September 17, 2012, between the Company and Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC, as representatives of the underwriters named in Schedule A thereto.

ARTICLE 2

GENERAL TERMS AND CONDITIONS OF THE DEBENTURES

Section 2.01. Designation, Principal Amount and Authorized Denominations.

(a) Designation . Pursuant to Sections 2.1 and 2.3 of the Base Indenture, there is hereby established a series of Securities of the Company designated as the 5.875% Junior Subordinated Debentures due 2052, the principal amount of which to be issued shall be in accordance with Section 2.01(b) hereof and as set forth in any Issuer Order for the authentication and delivery of Debentures pursuant to Section 2.4 of the Base Indenture, and the form and terms of which shall be as set forth hereinafter.

(b) Principal Amount . Debentures in an initial aggregate principal amount of $125,000,000 shall, upon execution of this Supplemental Indenture, be executed by the Company and delivered to the Trustee or an Authenticating Agent for authentication, and the Trustee or an Authenticating Agent shall thereupon authenticate and deliver said Debentures in accordance with Section 2.4 of the Base Indenture. Additional Debentures may be issued from time to time pursuant to this Supplemental Indenture on the same terms and conditions as the Debentures issued under this Supplemental Indenture in all respects, except for any difference in the issue date, issue price and, if applicable, the first payment of interest thereon and the initial interest accrual date. Additional Debentures issued pursuant to this Supplemental Indenture will be consolidated with, and will form a single series with, the previously outstanding Debentures issued pursuant to this Supplemental Indenture so long as any such additional Debentures have the same tenor and terms (including, without limitation, rights to receive accrued and unpaid interest as the previously outstanding Debentures); provided that no such additional Debentures may be issued unless they are treated as part of the same “issue” as the Debentures for U.S. federal income tax purposes; and further provided that the additional Debentures have the same CUSIP number as the Debentures. Any additional Debentures issued under this Supplemental Indenture will rank equally and ratably in right of payment with the Debentures originally issued under this Supplemental Indenture.

(c) Authorized Denominations. The denominations in which Debentures shall be issuable is a minimum of $25 principal amount and integral multiples of $25 thereafter.

Section 2.02. Repayment.

The principal of, and all accrued and unpaid interest on, all Outstanding Debentures shall be due and payable on December 15, 2052 or, if such date is not a Business Day, the following Business Day (the “ Maturity Date ”).

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Section 2.03. Form.

The Debentures shall be substantially in the form of Exhibit A attached hereto and shall be issued in fully registered definitive form without interest coupons. Principal of and interest on the Debentures issued in definitive form will be payable, the transfer of such Debentures will be registrable and such Debentures will be exchangeable for Debentures bearing identical terms and provisions and notices and demands to or upon the Company in respect of the Debentures and the Indenture may be served at the Corporate Trust Office of the Trustee, and the Company appoints the Trustee as its agent for the foregoing purposes, provided that payment of interest may be made at the option of the Company by check mailed to the Holders at such address as shall appear in the Security Register or by wire transfer in immediately available funds to the bank account number of the Holders specified in writing by the Holders not less than 10 days before the relevant Interest Payment Date and entered in the Security Register by the Security Registrar. The Debentures may be presented for registration of transfer or exchange at the Security Registrar Office. The Debentures are initially solely issuable as Global Securities. The Depository Trust Company is hereby designated as Depositary. Registered Debentures shall be physically transferred to all beneficial owners in definitive form in exchange for their beneficial interests in a Global Security if the Depositary with respect to such Global Securities notifies the Company that it is unwilling or unable to continue as Depositary for such Global Security or the Depositary ceases to be a clearing agency registered under the Exchange Act, as the case may be, and a successor Depositary is not appointed by the Company within 90 days of such notice.

In addition, beneficial interests in the Global Securities may be exchanged for definitive certificated Debentures upon request by or on behalf of the Depositary in accordance with customary procedures following the request of a beneficial owner seeking to exercise or enforce its rights under such Debentures in connection with an Event of Default. If the Company determines at any time that the Debentures shall no longer be represented by a Global Security, the Company shall inform the Depositary of such determination which will, in turn, notify participants of their right to withdraw their beneficial interest from the Global Security. If such participants then elect to withdraw their beneficial interests, the Company shall issue certificates in definitive form in exchange for such beneficial interests in the Global Security. Any Global Security, or portion thereof, that is exchangeable pursuant to this Section 2.03 shall be exchangeable for Debenture certificates registered in the names directed by the Depositary.

Section 2.04. Interest.

(a) From and including the original issue date up to but excluding the Maturity Date or earlier Redemption Date, as applicable, the Debentures will bear interest, accruing from the date of initial issuance (except as further described in the following sentence), at the per annum rate of 5.875% (the “ Coupon Rate ”), payable quarterly in arrears on each Interest Payment Date, commencing on December 15, 2012.

(b) Interest payments will include accrued interest from and including the last date in respect of which interest has been paid or duly provided for to, but excluding, the next succeeding Interest Payment Date, the Maturity Date or the Redemption Date, as the case may be. The amount of interest payable for any full Interest Payment Period will be computed on the basis of a 360-day year of twelve thirty-day months, and the amount of interest payable for any period shorter than a full Interest Payment Period for which interest is computed will be computed on the basis of thirty-day months and, for periods of less than a thirty-day month, the actual number of days elapsed per thirty-day month.

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(c) Otherwise than in connection with the maturity or early redemption of the Debentures or the payment in whole or in part of deferred or overdue interest on the Debentures, interest on the Debentures may be paid only on an Interest Payment Date. Notwithstanding the preceding sentence, in the event that any Interest Payment Date is not a Business Day, then payment of interest payable on such Interest Payment Date will be made on the next succeeding day which is a Business Day (and without any interest or other payment in respect of such delay).

(d) To the extent permitted by applicable law, interest not paid when due hereunder, including, without limitation, all deferred interest, will accrue and compound quarterly at the Coupon Rate on each Interest Payment Date until paid. References to the term “interest” in this Indenture shall include such Compounded Interest.

(e) For so long as the Debentures are represented by one or more Global Securities, the interest installment so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in the Base Indenture, be paid to the Person in whose name the Debentures (or one or more Predecessor Securities) are registered at the close of business on the Regular Record Date next preceding the Interest Payment Date, which shall be the record date for such Interest Payment Date; provided that, in the event the Debentures at any time are not represented solely by one or more Global Securities, the Company may select a different record date for such Interest Payment Date, which shall be at least one Business Day before an Interest Payment Date. Any such interest installment not punctually paid or duly provided for shall forthwith cease to be payable to the registered Holders of Debentures on such record date, and may be paid to the Person in whose name the Debentures (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 after the Company has deposited with the Trustee an amount of money equal to the aggregate amount proposed to be paid in respect of such defaulted interest, notice whereof shall be given to the registered Holders of 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 Debentures may be listed, and upon such notice as may be required by such exchange.

Section 2.05. Interest Deferral.

(a) Option to Defer Interest Payments .

(i) So long as no Event of Default with respect to the Debentures has occurred and is continuing, the Company shall have the right on one or more occasions, to defer the payment of interest on the Debentures for one or more Interest Payment Periods up to five consecutive years, provided that no Deferral Period shall extend beyond the Maturity Date, the earlier accelerated maturity date of the Debentures or other redemption in full of the Debentures. If the Company shall fail to pay interest on the Debentures on any Interest Payment Date, the Company shall be deemed to elect to defer payment of such interest on such Interest Payment Date, unless the Company shall pay

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such interest in full within five Business Days after any such Interest Payment Date. If the Company shall have paid all deferred interest on the Debentures, the Company shall have the right to elect to begin a new Deferral Period pursuant to this Section 2.05.

(ii) During a Deferral Period, interest will continue to accrue on the Debentures at the Coupon Rate, compounded quarterly, as of each Interest Payment Date to the extent permitted by applicable law.

(iii) The Company shall pay all deferred interest in accordance with the provisions of Section 2.7 of the Base Indenture applicable to Defaulted Interest.

(b) Payment of Deferred Interest . On the Maturity Date or if the principal amount of the Debentures shall have been accelerated and such acceleration has not been rescinded, the Company shall pay all accrued and unpaid interest, including deferred interest, from any available funds. On any Interest Payment Date the Company may pay any accrued and unpaid interest from any available funds.

(c) Notice of Deferral . The Company shall provide written notice to the Trustee and the Holders of the Debentures of its election to commence or continue any Deferral Period at least one Business Day and not more than sixty Business Days prior to the applicable Interest Payment Date. Notice of the Company’s election of a Deferral Period shall be given to the Trustee and each Holder of Debentures at such Holder’s address appearing in the Security Register by first-class mail, postage prepaid. Notwithstanding the foregoing, the failure of the Company to provide notice in accordance with this Section 2.05(c) of its election to commence or continue any Deferral Period, including any deemed election as provided in Section 2.05(a)(i), shall not affect the validity of such deferral hereunder.

Section 2.06. Events of Default.

Solely for purposes of the Debentures, the first paragraph of Section 5.1, Section 5.1(a)-(i) and the following three paragraphs of the Base Indenture shall be deleted and replaced by the following:

Section 5.1. EVENTS OF DEFAULT.

“Event of Default”, wherever used herein with respect to the Debentures, means any one of the following events (whatever the reason for such Event of Default and whether it shall be voluntary or involuntary or be effected by operation of law or pursuant to any judgment, decree or order of any court or any order, rule or regulation of any administrative or governmental body):

(a) default in the payment of interest in full, including Compounded Interest, on any Debenture for a period of 30 days, other than during a Deferral Period, or on the Maturity Date;

(b) default in the payment of principal of or premium, if any, on any Debenture on the Maturity Date or upon redemption;

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(c) failure by the Company to comply in any material respect with any of its agreements or covenants in, or any of the provisions of, the Indenture with respect to the Debentures (other than an agreement, covenant or provision for which non-compliance is elsewhere in this Section specifically dealt with), and such non-compliance continues for a period of 60 days after there has been given, by registered or certified mail, to the Company by the Trustee or to the Company and the Trustee by the Holders of at least 25% in principal amount of the Outstanding Debentures, a written notice specifying such default or breach and requiring it to be remedied and stating that such notice is a “Notice of Default” hereunder;

(d) a default under any mortgage, agreement, indenture or instrument under which there may be issued, or by which there may be secured, guaranteed or evidenced any Debt of the Company (including this Indenture) whether such Debt now exists or shall hereafter be created, in an aggregate principal amount then outstanding of $10,000,000 or more, which default (i) shall constitute a failure to pay any portion of the principal of such Debt when due and payable after the expiration of any applicable grace period with respect thereto or (ii) shall result in such Debt becoming or being declared due and payable prior to the date on which it would otherwise become due and payable, and such acceleration shall not be rescinded or annulled, or such Debt shall not be paid in full within a period of 30 days after there has been given, by registered or certified mail, to the Company by the Trustee or to the Company and the Trustee by the Holders of at least 25% in aggregate principal amount of the Debentures a written notice specifying such event of default and requiring the Company to cause such acceleration to be rescinded or annulled or to pay in full such Debt and stating that such notice is a “Notice of Default” hereunder; (it being understood however, that the Trustee shall not be deemed to have knowledge of such default under such agreement or instrument unless either (i) a Responsible Officer of the Trustee shall have actual knowledge of such default or (ii) a Responsible Officer of the Trustee shall have received written notice thereof from the Company or from any Holder); provided , however, that if such default under such agreement or instrument is remedied or cured by the Company or waived by the holders of such indebtedness, then the Event of Default hereunder by reason thereof shall be deemed likewise to have been thereupon remedied, cured or waived without further action upon the part of either the Trustee or any of such Holders; provided , further, that the foregoing shall not apply to any secured Debt under which the obligee has recourse (exclusive of recourse for ancillary matters such as environmental indemnities, misapplication of funds, costs of enforcement and the like) only to the collateral pledged for repayment so long as the fair market value of such collateral does not exceed 2% of Total Assets at the time of the default;

(e) the Company, pursuant to or within the meaning of any Bankruptcy Law, (i) commences a voluntary case or proceeding, (ii) consents to the entry of an order for relief against it in an involuntary case or proceeding, (iii) consents to the appointment of a Custodian of it or for all or substantially all of its property, (iv) makes a general assignment for the benefit of its creditors (v) makes an admission in writing of its inability to pay its debts generally as they become due or (vi) takes corporate action in furtherance of any such action; or

(f) a court of competent jurisdiction enters an order or decree under any Bankruptcy Law that (i) is for relief against the Company, in an involuntary case, (ii) adjudges the Company as bankrupt or insolvent, or approves as properly filed a petition seeking reorganization, arrangement, adjustment or composition of or in respect of the Company, or appoints a Custodian of the Company, or for all or substantially all of its property, or (iii) orders the liquidation of the Company, and the order or decree remains unstayed and in effect for 60 days.

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The Trustee shall have no right or obligation under the Indenture or otherwise to exercise any remedies on behalf of the Holders of the Debentures in connection with any failure by the Company to comply with any covenant or warranty of the Company contained in the Base Indenture (other than any covenant referred to in Section 5.1(a) or (b)), unless the Trustee is directed to exercise such remedies pursuant to and subject to the provisions of Section 5.9 of the Base Indenture. If an Event of Default has occurred under Section 5.1(e) or Section 5.1(f), the principal of and accrued but unpaid interest on the Debentures shall automatically, and without any declaration or other action on the part of the Trustee or any Holder of the Debentures, become immediately due and payable. In connection with any such exercise of remedies, the Trustee shall be entitled to the same immunities and protections and remedial rights (other than acceleration) as if such failure to comply were an Event of Default. The Trustee shall not be charged with knowledge or notice of any such failure to comply unless and until it shall have received the foregoing direction under Section 5.9 of the Base Indenture.

Section 2.07. Security Registrar; Paying Agent.

The Company appoints The Bank of New York Mellon Trust Company, N.A. as Security Registrar and Paying Agent with respect to the Debentures.

Section 2.08. Subordination.

The subordination provisions of Article XIII of the Base Indenture shall apply to the Debentures, provided that , for purposes of such Article XIII, Senior Indebtedness will not include (i) (A) any indebtedness which by its terms ranks equally with the Debentures in right of payment, including guarantees of such indebtedness, (B) any indebtedness which by its terms is subordinated to the Debentures in right of payment, which shall rank junior in right of payment to the Debentures, (C) any indebtedness incurred for the purchase of goods or material or for services obtained in the ordinary course of business, which shall rank equally in right of payment to the Debentures, (D) indebtedness owed by the Company to its subsidiaries, including the Company’s existing 7.100% Junior Subordinated Debentures due 2046, which shall rank equally in right of payment to the Debentures or (E) indebtedness owed by the Company to its employees, which shall rank equally in right of payment to the Debentures.

Section 2.09. Satisfaction, Discharge and Defeasance.

The provisions of Article X of the Base Indenture shall apply to the Debentures.

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ARTICLE 3

COVENANTS

Section 3.01. Dividend and Other Payment Stoppages.

So long as any Debentures remain Outstanding, if the Company shall have given notice of its election to defer interest payments on the Debentures but the related Deferral Period has not yet commenced or a Deferral Period is continuing, the Company shall not, and shall not permit any Subsidiary of the Company to:

(a) declare or pay any dividends or distributions on, or redeem, purchase, acquire or make a liquidation payment with respect to, any shares of capital stock of the Company other than:

(i) purchases or acquisitions of shares of the Company’s capital stock in connection with the satisfaction by the Company of its obligations under any employment contract, benefit plan or other similar arrangement with or for the benefit of employees, officers, directors, consultants or agents of the Company or its subsidiaries, or in connection with the satisfaction by the Company of its obligations under any dividend reinvestment plan;

(ii) purchases or acquisitions of shares of the Company’s capital stock in satisfaction of the Company’s obligations under any contract or security requiring it to purchase shares of its capital stock entered into prior to the commencement of the deferral period;

(iii) as a result of a reclassification of any series or class of the Company’s capital stock, or the exchange or conversion of one class or series of the Company’s capital stock for or into another class or series of its capital stock;

(iv) the purchase of fractional interests in shares of the Company’s capital stock pursuant to an acquisition or the conversion or exchange provisions of that capital stock or the security being converted or exchanged;

(v) dividends or distributions of the Company’s capital stock, or rights to acquire capital stock, or repurchases or redemptions of capital stock, in each case solely from the issuance or exchange of capital stock;

(vi) any declaration of a dividend in connection with the implementation of a shareholder rights plan, or issuances of capital stock under any such plan in the future, or redemptions or repurchases of any rights outstanding under a shareholder rights plan; or

(vii) acquisitions of the Company’s capital stock in connection with acquisitions of businesses made by the Company (which acquisitions are made by the Company in connection with the satisfaction of indemnification obligations of the sellers of such businesses); or

(b) make any payment of principal, premium, if any, or interest on, or repay, repurchase or redeem, any of the Company’s debt securities or guaranties that rank equally with the Debentures (the “ Parity Securities ”) or junior to the Debentures, other than (i) any payment of current or deferred interest on Parity Securities and the Debentures made pro rata to the amounts due on such Parity Securities and the Debentures; (ii) any payments of deferred interest on Parity Securities that, if not made, would cause the Company to breach the terms of the instrument governing such Parity Securities; or (iii) any payment of principal on Parity Securities necessary to avoid a breach of the instrument governing such Parity Securities.

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ARTICLE 4

REDEMPTION OF THE DEBENTURES

Section 4.01. Redemption.

(a) The Debentures shall be redeemable in accordance with Article XII of the Base Indenture, except to the extent otherwise provided in this Supplemental Indenture:

(i) in whole at any time or in part from time to time on or after December 15, 2017; or

(ii) in whole, but not in part, at any time prior to December 15, 2017, within 90 days after the occurrence of a Tax Event;

provided that no partial redemption pursuant to Section 4.01(a)(i) shall be effected (x) unless at least $25 million aggregate principal amount of the Debentures shall remain Outstanding after giving effect to such redemption and (y) if the principal amount of the Debentures shall have been accelerated and such acceleration has not been rescinded or unless all accrued and unpaid interest, including deferred interest, shall have been paid in full on all Outstanding Debentures for all Interest Payment Periods terminating on or before the Redemption Date.

(b) Notwithstanding any provision of Article XII of the Base Indenture to the contrary, the Debentures shall be subject to partial redemption only in the amount of $25 and integral multiples of $25 in excess thereof.

Section 4.02. Redemption Price.

The Redemption Price for any redemption pursuant to Section 4.01 will be equal to (1) in the case of any redemption pursuant to Section 4.01(a)(i), 100% of the principal amount of the Debentures being redeemed, plus accrued and unpaid interest to but excluding the Redemption Date or (2) in the case of any redemption pursuant to Section 4.01(a)(ii), $26 per $25 principal amount of the Debentures being redeemed, plus accrued and unpaid interest to but excluding the Redemption Date.

ARTICLE 5

ORIGINAL ISSUE OF DEBENTURES

Section 5.01. Original Issue of Debentures.

Debentures in the aggregate principal amount not to exceed $125,000,000, except as provided in Section 2.01(b) hereof, may, upon execution of this Supplemental Indenture, be executed by the Company and delivered to the Trustee for authentication, and the Trustee shall thereupon authenticate and deliver said Debentures to or upon the written order of the Company, signed by its Chief Executive Officer, its President, or any Vice President (or more senior officer) and its Treasurer or an Assistant Treasurer, without any further action by the Company.

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Section 5.02. Calculation of Original Issue Discount.

If during any calendar year any original issue discount shall have accrued on the Debentures, the Company shall file with each Paying Agent (including the Trustee if it is a Paying Agent) by January 31 of the following calendar year (a) a written notice specifying the amount of original issue discount (including daily rates and accrual periods) accrued on Outstanding Debentures as of the end of such year and (b) such other specific information relating to such original issue discount as may then be relevant under the Internal Revenue Code of 1986, as amended from time to time.

ARTICLE 6

MISCELLANEOUS

Section 6.01. Effectiveness.

This Supplemental Indenture will become effective upon its execution and delivery.

Section 6.02. Effect of Recitals.

The recitals contained herein and in the Debentures, except the Trustee’s certificates of authentication, shall be taken as the statements of the Company, and neither the Trustee nor any Authenticating Agent assumes any responsibility for their correctness. The Trustee makes no representations as to the validity or sufficiency of this Supplemental Indenture or of the Debentures. Neither the Trustee nor any Authenticating Agent shall be accountable for the use or application by the Company of the Debentures or the proceeds thereof.

Section 6.03. Ratification of Base Indenture; Conflicts.

The Base Indenture, as supplemented by this Supplemental Indenture, is in all respects ratified and confirmed, and this Supplemental Indenture shall be deemed part of the Indenture in the manner and to the extent herein and therein provided. In the event of any conflict between this Supplemental Indenture and the Base Indenture or the provisions set forth in the certificates of Debentures, as the case may be, this Supplemental Indenture shall control.

Section 6.04. Debentures Unaffected by Officer’s Certificates.

None of the Company’s officer’s certificates pursuant to the Base Indenture entered into prior to the date hereof applies to the Debentures. To the extent the terms of the Base Indenture are amended by any of such officer’s certificates, no such amendment shall relate or apply to the Debentures. To the extent the terms of the Base Indenture are amended as provided herein, no such amendment shall in any way affect the terms of any such officer’s certificate or any other series of Securities. This Supplemental Indenture shall relate and apply solely to the Debentures.

Section 6.05. Tax Treatment.

The Company agrees, and by acceptance of a Debenture or a beneficial interest in a Debenture each Holder of a Debenture and any Person acquiring a beneficial interest in a Debenture agrees, to treat the Debentures as indebtedness for United States federal income tax purposes.

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Section 6.06. Governing Law.

This Supplemental Indenture, the Indenture as supplemented hereby and the Debentures shall be governed by and construed in accordance with the laws of the State of New York without regard to the principles of conflict of laws.

Section 6.07. Severability.

In case any provision in this Supplemental Indenture, the Indenture as supplemented hereby or in the 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 6.08. Counterparts.

This Supplemental Indenture may be executed in any number of counterparts each of which shall be an original; but such counterparts shall together constitute but one and the same instrument.

Section 6.09. Waiver of Jury Trial.

EACH OF THE COMPANY AND THE TRUSTEE HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS INDENTURE, THE SECURITIES OR THE TRANSACTION CONTEMPLATED HEREBY.

Section 6.10. Force Majeure.

In no event shall the Trustee be responsible or liable for any failure or delay in the performance of its obligations hereunder arising out of or caused by, directly or indirectly, forces beyond its control, including, without limitation, strikes, work stoppages, accidents, acts of war or terrorism, civil or military disturbances, nuclear or natural catastrophes or acts of God, and interruptions, loss or malfunctions of utilities, communications or computer (software and hardware) services; it being understood that the Trustee shall use reasonable efforts which are consistent with accepted practices in the banking industry to resume performance as soon as practicable under the circumstances.

Section 6.11. Trustee Liability.

In no event shall the Trustee be responsible or liable for special, indirect, or consequential loss or damage of any kind whatsoever (including, but not limited to, loss of profit) unless it shall be proved that the Trustee acted in bad faith or was grossly negligent in acting or failing to act.

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IN WITNESS WHEREOF, the Company has caused this First Supplemental Indenture to be signed and delivered, and the Trustee has caused this First Supplemental Indenture to be signed and delivered, all as of the day and year first written above.

[Signature Page to First Supplemental Indenture]

Exhibit A

[FORM OF FACE OF DEBENTURE]

[UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY SECURITY ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF DTC OR A NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN DTC OR SUCH NOMINEE, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.] ¹

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TORCHMARK CORPORATION

5.875% Junior Subordinated Debentures due 2052

TORCHMARK CORPORATION, a corporation organized and existing under the laws of Delaware (hereinafter called the “ Company ”, which term includes any successor corporation under the Indenture hereinafter referred to), for value received, hereby promises to pay to [Cede & Co.] ² , or registered assigns, the principal sum of One Hundred Twenty Five Million Dollars ($125,000,000), and all accrued and unpaid interest thereon on December 15, 2052 or, if such date is not a Business Day, the following Business Day (the “ Maturity Date ”).

The Company further promises to pay interest on said principal sum from September 24, 2012 or from the most recent interest payment date to which interest has been paid or duly provided for. Until the Maturity Date or earlier Redemption Date, each Debenture will bear interest at the per annum rate of 5.875% (the “ Coupon Rate ”) payable (subject to the interest deferral provisions of Section 2.05 of the Supplemental Indenture) quarterly in arrears on March 15, June 15, September 15 and December 15 of each year (each such date, an “ Interest Payment Date ”), commencing on December 15, 2012, and (to the extent that payment of such interest is enforceable under applicable law) on any overdue installment of interest at such interest rate, compounded quarterly. Interest payments will include accrued interest from and including the last date in respect of which interest has been duly paid or provided for to, but not including, the next succeeding Interest Payment Date, the Maturity Date or the Redemption Date, as the case may be. The amount of interest payable for any full Interest Payment Period will be computed on the basis of a 360-day year of twelve thirty-day months, and the amount of interest payable for any period shorter than a full Interest Payment Period for which interest is computed will be computed on the basis of thirty-day months and, for periods of less than a thirty-day month, the actual number of days elapsed per thirty-day month.

In the event that any date on which interest is payable on this Debenture 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 such delay). For so long as the Debentures are represented by one or more Global Securities, the interest installment so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in the Base Indenture, be paid to the Person in whose name this Debenture (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date next preceding the Interest Payment Date, which shall be the record date for such Interest Payment Date; provided that in the event the Debentures at any time are not represented solely by one or Global Securities, the Company may select a different record date for such Interest Payment Date, which shall be at least one Business Day before an Interest Payment Date. Any such interest installment not punctually paid or duly provided for shall forthwith cease to be payable to the registered Holders on such record date, and may be paid to the Person in whose

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name the Debentures (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 after the Company has deposited with the Trustee an amount of money equal to the aggregate amount proposed to be paid in respect of such defaulted interest, notice whereof shall be given to the registered Holders of this series of Debenture not less than ten 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 Debentures may be listed, and upon such notice as may be required by such exchange, all as more fully provided in the Indenture.

The principal of (and premium, if any) and the interest (including Compounded Interest) on this Debenture shall be payable at the office or agency of the Trustee maintained for that purpose in the United States, in any coin or currency of the United States of America which at the time of payment is legal tender for payment of public and private debts; provided, however, that payment of interest may be made at the option of the Company by check mailed to the registered Holder at such address as shall appear in the Security Register; provided further that, notwithstanding the foregoing provisions of this sentence, for so long as the Depositary (as defined in the Indenture referred to on the reverse hereof) is the Holder of all of the Debentures Outstanding, and provided that the Depositary has provided wire transfer instructions to the Company or the Paying Agent in a timely manner prior to each Interest Payment Date (which it may do by standing instructions) designating an account of the Depositary or its nominee at a commercial bank in the United States to which it wishes payments of interest on the Debentures to be made, the Company shall pay interest on the Debentures by wire transfer of federal (same day) funds to the account of the Depositary or its nominee in accordance with such wire transfer instructions.

The indebtedness evidenced by this Debenture is, to the extent provided in the Indenture, subordinate and subject in right of payment to the prior payment in full of all Senior Indebtedness, and this Debenture is issued subject to the provisions of the Indenture with respect thereto. Each Holder of this Debenture by accepting the same, (a) agrees to and shall be bound by such provisions, (b) authorizes and directs the Trustee on its behalf to take such actions as may be necessary or appropriate to effectuate the subordination so provided and (c) appoints the Trustee its attorney-in-fact for any and all such purposes. Each Holder hereof, by its acceptance hereof, 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.

As provided in the Indenture, so long as no Event of Default has occurred and is continuing, the Company shall have the right on one or more occasions, to defer the payment of interest for one or more Interest Payment Periods up to five consecutive years, provided that no Deferral Period shall extend beyond the Maturity Date, the earlier accelerated maturity date hereof or other redemption in full hereof. If the Company shall fail to pay interest hereon on any Interest Payment Date, the Company shall be deemed to elect to defer payment of such interest on such Interest Payment Date, unless the Company shall pay such interest in full within five Business Days after any such Interest Payment Date. If the Company shall have paid all deferred interest hereon, the Company shall have the right to elect to begin a new Deferral Period as provided in the Indenture.

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Reference is hereby made to the further provisions of this Debenture 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 Debenture shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

Any additional Debentures issued under the same CUSIP as this Debenture shall be fungible with this Debenture for U.S. federal income tax purposes.

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IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

Dated: September 24, 2012

Certificate of Authentication

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

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REVERSE OF SECURITY

This Debenture 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 a Subordinated Indenture, dated as of November 2, 2001 (herein called the “ Base Indenture ”), between the Company and The Bank of New York Mellon Trust Company, N.A., as Trustee (herein called the “ Trustee ”, which term includes any successor trustee under the Indenture), as supplemented and amended by the Supplemental Indenture, dated as of September 24, 2012, between the Company and the Trustee (the “ Supplemental Indenture ”, and together with the Base Indenture, the “ Indenture ”), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Trustee, the Company and the Holders of the Debentures, and of the terms upon which the Debentures are, and are to be, authenticated and delivered. The terms of the Debentures include those stated in the Indenture, and the Debentures are subject to all such terms. This Debenture is one of the series designated on the face hereof, initially limited in aggregate principal amount to $125,000,000.

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

This Debenture shall be redeemable at the option of the Company in accordance with the terms of the Indenture. In particular, this Security is redeemable:

(a) in whole at any time or in part from time to time on or after December 15, 2017; or

(b) in whole, but not in part, at any time prior to December 15, 2017 within 90 days after the occurrence of a Tax Event;

provided that no such partial redemption shall be effected (x) unless at least $25 million aggregate principal amount of Securities of this series shall remain Outstanding after giving effect to such redemption and (y) if the principal amount of the Debentures of this series shall have been accelerated and such acceleration has not been rescinded or unless all accrued and unpaid interest, including deferred interest, shall have been paid in full on all Outstanding Debentures for all Interest Payment Periods terminating on or before the Redemption Date.

Notice of redemption shall be mailed at least 30 but not more than 60 days before the Redemption Date to each Holder of Securities of this series to be redeemed at its registered address. The notice of redemption for such Debentures shall state, among other things, the amount of Debentures to be redeemed, the Redemption Date, if not then ascertainable, the manner in which the Redemption Price shall be calculated and the place or places that payment shall be made upon presentation and surrender of such Debenture to be redeemed. Unless the Company defaults in the payment of the Redemption Price together with accrued interest, interest will cease to accrue on any Debentures that have been called for redemption on the Redemption Date.

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In the event of redemption of this Debenture in part only, a new Debenture or Debentures for the unredeemed portion hereof will be issued in the name of the Holder hereof upon the cancellation hereof.

Installments of accrued and unpaid interest whose Stated Maturity is on or prior to the Redemption Date will be payable to the Holders of the Debentures, or one or more Predecessor Securities, registered as such at the close of business on the relevant Regular Record Dates according to their terms.

The Indenture contains provisions for satisfaction, discharge and defeasance of the entire indebtedness on this Debenture, upon compliance by the Company with certain conditions set forth therein.

The Debentures are not entitled to the benefit of any sinking fund.

If an Event of Default with respect to the Debentures shall occur and be continuing, the principal of the Debentures may be declared due and payable in the manner and with the effect provided in the 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 a majority in principal amount of the Securities at the time Outstanding of each series to be affected. The Indenture also contains provisions permitting 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 Debenture shall be conclusive and binding upon such Holder and upon all future Holders of this Debenture 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 Debenture.

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

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Debenture is registrable in the Security Register, upon surrender of this Debenture for registration of transfer at the office or agency of the Company in any place where the principal of (and premium, if any) and interest on this Debenture are payable duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Debentures, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.

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The Debenture are issuable only in registered form without coupons in denominations of $25 and any integral multiples of $25 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Debentures are exchangeable for a like aggregate principal amount of Debentures 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.

The Company, the Trustee and any agent of the Company or the Trustee may treat the Person in whose name this Debenture 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.

No recourse shall be had for the payment of the principal of or the interest on this Debenture, or for any claim based hereon, or otherwise in respect hereof, or based on or in respect of the Indenture, against any incorporator, shareholder, officer or director, past, present or future, as such, of the Company or of any predecessor or successor corporation, whether by virtue of any constitution, statute or rule of law, or by the enforcement of any assessment or penalty or otherwise, all such liability being, by the acceptance hereof and as part of the consideration for the issuance hereof, expressly waived and released.

THIS DEBENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE PRINCIPLES OF CONFLICT OF LAWS.

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ASSIGNMENT

FOR VALUE RECEIVED, the undersigned assigns and transfers this Debenture to:

(Insert assignee’s social security or tax identification number)

(Insert address and zip code of assignee)

agent to transfer this Debenture on the books of the Security Registrar. The agent may substitute another to act for him or her.

(Sign exactly as your name appears on the other side of this Security)

Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Security Registrar, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“ STAMP ”) or such other “signature guarantee program” as may be determined by the Security Registrar in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.

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