CITIGROUP
      INC.

     

    AND

     

    THE
      BANK
      OF NEW YORK 

    (as
      successor-in-interest to JPMorgan Chase Bank, N.A.) 

     

    Trustee

     

    SECOND
      SUPPLEMENTAL INDENTURE

     

    Dated
      as
      of March 6, 2007

    


    Supplemental
      to Indenture dated as of September 15, 2006

    providing
      for the issuance of

    Junior
      Subordinated Deferrable Interest Debentures

     

     

    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    


    SECOND
      SUPPLEMENTAL INDENTURE, dated as of March 6, 2007 (the "Second Supplemental
      Indenture"), between CITIGROUP INC., a Delaware corporation (the "Company"),
      and
      THE BANK OF NEW YORK, a national banking association (as successor-in-interest
      to JPMorgan Chase Bank, N.A.), as trustee (the "Trustee"), under the Indenture
      dated as of September 15, 2006 (as supplemented, the "Indenture"). Capitalized
      terms used but not defined herein shall have the meanings ascribed thereto
      under
      the Indenture.

     

    WHEREAS,
      pursuant to Section 9.01(7) of the Indenture, the Company and the Trustee may
      enter into a supplemental indenture to cure any ambiguity, to correct or
      supplement any provision in the Indenture which may be inconsistent with any
      other provision in the Indenture, or to make any other provisions with respect
      to matters or questions arising under the Indenture, provided
      such
      action shall not adversely affect the interests of the Holders of Securities
      of
      any series in any material respect;

     

    WHEREAS,
      the Company and the Trustee desire to enter into this Second Supplemental
      Indenture;

     

    NOW,
      THEREFORE, the Company covenants and agrees with the Trustee as
      follows:

     

    ARTICLE
      ONE

     

    The
      modifications in this Article One shall have no effect upon any series of
      Securities Outstanding on the date hereof but shall be applicable only to
      Securities issued after the date hereof.

    


    Section
      1.01. Section
      1.1 shall be amended by deleting the definition of "Market Disruption Event"
      in
      its entirely and substituting therefor the following:

     

    ""Market
      Disruption Event," means the occurrence or existence of any of the following
      events or circumstances:

     

    (1) the
      Company would be required to obtain the consent or approval of its shareholders
      or a regulatory body (including, without limitation, any securities exchange
      but
      excluding the Federal Reserve) or governmental authority to issue or sell shares
      of its common stock and such consent or approval has not yet been obtained
      even
      though the Company has used commercially reasonable efforts to obtain the
      required consent or approval;

     

    (2) trading
      in securities generally on the principal exchange on which the Company's
      securities are listed and traded (as of the date hereof, the New York Stock
      Exchange) shall have been suspended or materially disrupted or minimum prices
      shall have been established on any such exchange or market by the Commission,
      by
      the relevant exchange or any other regulatory body or by governmental authority
      having jurisdiction;

     

    
      
        
        

      

      
        2

        
          

        

      

      
        
        

      

    

     

    (3) an
      event
      occurs and is continuing as a result of which the offering document for such
      offer and sale of securities would, in the reasonable judgment of the Company,
      contain an untrue statement of a material fact or omit to state a material
      fact
      required to be stated therein or necessary to make the statements therein not
      misleading and either (1) the disclosure of that event at such time, in the
      reasonable judgment of the Company, would have a material adverse effect on
      the
      Company's business or (2) the disclosure relates to a previously undisclosed
      proposed or pending material development or business transaction, and the
      Company has a bona fide business reason for keeping the same confidential or
      the
      disclosure of which would impede the Company's ability to consummate such
      transaction, provided that no single suspension period contemplated by this
      paragraph (iii) may exceed 90 consecutive days and multiple suspension periods
      contemplated by this paragraph (iii) may not exceed an aggregate of 180 days
      in
      any 360-day period;

     

    (4) the
      Company reasonably believes that the offering document for such offer and sale
      of securities would not be in compliance with a rule or regulation of the
      Commission (for reasons other than those referred to in paragraph (iii) above)
      and the Company is unable to comply with such rule or regulation or such
      compliance is impracticable, provided that no single suspension contemplated
      by
      this paragraph (iv) may exceed 90 consecutive days and multiple suspension
      periods contemplated by this paragraph (iv) may not exceed an aggregate of
      180
      days in any 360-day period;

     

    (5) there
      is
      an adverse change in general domestic or international economic, political
      or
      financial conditions, including without limitation as a result of terrorist
      activities, or the effect of international conditions on the financial markets
      in the United States and such adverse change materially disrupts or otherwise
      has a material adverse effect on the issuance, sale or trading of the Company's
      common stock; 

     

    (6) a
      material disruption shall have occurred in commercial banking or securities
      settlement or clearing services in the United States; or

     

    (7) a
      banking
      moratorium shall have been declared by federal or state authorities of the
      United States."

     

    Section
      1.02. Section
      1.1 shall be amended by deleting the definition of "New Equity Amount" in its
      entirely and substituting therefor the following:

     

    ""New
      Equity Amount" means, at any date, (i) the net cash proceeds (after
      underwriters’ or placement agents’ fees, commissions or discounts and other
      expenses relating to the issuances), plus (ii) the fair market value of
      property, other than cash (based on the Current Stock Market Price of common
      stock issued or delivered for such property), received by the Company during
      the
      180-day period immediately prior to such date in arm's length transactions,
      from
      the issuance or sale of shares of (A) the Company's common stock, including
      treasury shares and shares of common stock sold pursuant to the Company's
      dividend reinvestment plan and employee benefit plans and (B) the Company's
      Qualified Warrants."

     

    
      
        
        

      

      
        3

        
          

        

      

      
        
        

      

    

     

    Section
      1.03. Section
      1.1 shall be amended by deleting the definition of "Qualified Warrants" in
      its
      entirely and substituting therefor the following:

     

    ""Qualified
      Warrants" means warrants for the Company's common stock that (1) have an
      exercise price greater than the Current Stock Market Price of the Company's
      common stock on their date of issuance, and (2) the Company is not entitled
      to
      redeem for cash and the holders are not entitled to require the Company to
      repurchase for cash in any circumstances."

     

    Section
      1.04. Section
      2.3 shall be amended by deleting the eighth paragraph of such section in its
      entirety and substituting therefor the following:

     

    "The
      Company shall have the right at any time during the term of the Securities
      and
      from time to time to extend the interest payment period of such Securities
      for
      up to 40 consecutive quarters (an "Extended Interest Payment Period"), at the
      end of which period the Company shall pay all interest then accrued and unpaid
      (together with interest thereon at the rate specified for the Securities to
      the
      extent that payment of such interest is enforceable under applicable law);
      provided,
      that no
      such Extended Interest Payment Period shall extend beyond the maturity of the
      Securities; and provided
      further
      that
      during any such Extended Interest Payment Period (a) the Company and any
      subsidiary of the Company shall not declare or pay any dividend on, make any
      distributions with respect to, or redeem, purchase, acquire or make a
      liquidation payment with respect to, any of its capital stock or make any
      guarantee payment with respect thereto (other than (i) purchases, redemptions
      or
      other acquisitions of shares of capital stock of the Company in connection
      with
      any employment contract, benefit plan or other similar arrangement with or
      for
      the benefit of employees, officers, directors or consultants, (ii) purchases
      of
      shares of common stock of the Company pursuant to a contractually binding
      requirement to buy stock existing prior to the commencement of the Extended
      Interest Payment Period, including under a contractually binding stock
      repurchase plan, (iii) as a result of an exchange or conversion of any class
      or
      series of the Company's capital stock for any other class or series of the
      Company's capital stock, (iv) the purchase of fractional interests in shares
      of
      the Company's capital stock pursuant to the conversion or exchange provisions
      of
      such capital stock or the security being converted or exchanged) or (v) the
      purchase of capital stock of the Company in connection with the distribution
      thereof), and (b) the Company and any subsidiary of the Company will not make
      any payment of interest, principal or premium on, or repay, purchase or redeem,
      any debt securities or guarantees issued by the Company that rank pari passu
      with or junior to the Securities (other than (i) any payment of current or
      Deferred Interest on securities that rank pari passu with the Securities that
      is
      made pro rata to the amounts due on such securities (including the Securities),
      provided that any such payments of Deferred Interest are made in accordance
      with
      Section 13.5(d) of the Indenture or (ii) any payments of Deferred Interest
      on
      securities that rank pari passu with the Securities that, if not made, would
      give rise to an event of default permitting acceleration of such securities.
      The
      foregoing, however, will not apply to any stock dividends paid by the Company
      where the dividend stock is the same stock as that on which the dividend is
      being paid. Before the termination of any such Extended Interest Payment Period,
      the Company may further extend such Extended Interest Payment Period,
provided
      that
      such Extended Interest Payment Period together with all such previous and
      further extensions thereof shall not exceed 40 consecutive quarters. At the
      termination of any such Extended Interest Payment Period and upon the payment
      of
      all accrued and unpaid interest and any additional amounts then due, the Company
      may commence a new Extended Interest Payment Period. The Company may pay current
      interest at any time with cash from any source."

     

    
      
        
        

      

      
        4

        
          

        

      

      
        
        

      

    

     

    Section
      1.05. Section
      8.3 shall be amended by deleting such section in its entirety and substituting
      therefor the following:

     

    "If
      the
      Company is involved in a business combination where, immediately after the
      consummation of such business combination, more than 50% of the surviving
      entity’s voting stock is owned by the shareholders of the other party to the
      business combination, then:

     

    (1) any
      Deferred Interest on the Securities as of the date of consummation of the
      business combination shall not be subject to the requirements of
      Section 13.4 and Section 13.5 to the extent that the applicable
      Extended Interest Payment Period is terminated on the next Interest Payment
      Date
      following the date of consummation of the business combination (or, if later,
      at
      any time within 90 days following the date of such consummation);
      and

     

    (2) the
      Company’s covenant not to, and to not permit its subsidiaries to, purchase any
      of its common stock for a one year period following the end of an Extended
      Interest Payment Period that lasts longer than one year as described in Section
      13.3 will not apply to any Extended Interest Payment Period that is terminated
      on the next Interest Payment Date following the date of consummation of the
      business combination (or, if later, at any time within 90 days following the
      date of such consummation)."

     

    Section
      1.06. Section
      13.3 shall be amended by deleting such section in its entirety and substituting
      therefor the following:

     

    "If
      with
      respect to any series of Securities (i) the Company shall exercise its right
      to
      defer payments of interest thereon as provided in Section 13.1 or (ii) there
      shall have occurred any Default, then (a) the Company and any subsidiary of
      the
      Company shall not declare or pay any dividend on, make any distributions with
      respect to, or redeem, purchase, acquire or make a liquidation payment with
      respect to, any of its capital stock or make any guarantee payment with respect
      thereto (other than (i) purchases, redemptions or other acquisitions of shares
      of capital stock of the Company in connection with any employment contract,
      benefit plan or other similar arrangement with or for the benefit of employees,
      officers, directors or consultants, (ii) purchases of shares of common stock
      of
      the Company pursuant to a contractually binding requirement to buy stock
      existing prior to the commencement of the extension period, including under
      a
      contractually binding stock repurchase plan, (iii) as a result of an exchange
      or
      conversion of any class or series of the Company's capital stock for any other
      class or series of the Company's capital stock, (iv) the purchase of fractional
      interests in shares of the Company's capital stock pursuant to the conversion
      or
      exchange provisions of such capital stock or the security being converted or
      exchanged, or (v) purchase of the Company's capital stock in connection with
      the
      distribution thereof); and (b) the Company and any subsidiary of the Company
      will not make any payment of interest, principal or premium on, or repay,
      purchase or redeem, any debt securities or guarantees issued by the Company
      that
      rank pari passu with or junior to the Securities (other than (i) any payment
      of
      current or Deferred Interest on securities that rank pari passu with the
      Securities that is made pro rata to the amounts due on such securities
      (including the Securities), provided that any such payments of Deferred Interest
      are made in accordance with Section 13.5(d) or (ii) any payments of Deferred
      Interest on securities that rank pari passu with the Securities that, if not
      made, would give rise to an event of default permitting acceleration of such
      securities), provided,
      however,
      that
      the Company may declare and pay a stock dividend where the dividend stock is
      the
      same stock as that on which the dividend is being paid. If any Extended Interest
      Payment Period lasts longer than one year, unless required to do so by the
      Federal Reserve and subject to the exceptions listed in clauses (a) and (b)
      of
      this Section 13.3, the Company will not, and will not permit any subsidiary
      to
      purchase any of its common stock for a one-year period following the payment
      of
      all Deferred Interest with the New Equity Amount."

     

    
      
        
        

      

      
        5

        
          

        

      

      
        
        

      

    

     

    Section
      1.07. Section
      13.5 shall be amended by deleting paragraphs (b) and (d) in their entirety
      and
      substituting therefor the following:

     

    "(b) As
      used
      in this Section 13.5, the term “commercially reasonable efforts” means
      commercially reasonable efforts on the part of the Company to complete the
      sale
      of shares of its common stock, including treasury shares, to third parties
      that
      are not subsidiaries of the Company. The Company will not be considered to
      have
      used its commercially reasonable efforts to effect a sale of stock if it
      determines not to pursue or complete such sale solely due to pricing or dilution
      considerations."

     

    "(d) Following
      the earlier of (i) the Fifth Deferral Anniversary and (ii) the date of any
      payment of current interest during an Extended Interest Payment Period, the
      Company shall apply the net proceeds received by it from sales of shares of
      its
      common stock, including sales of treasury shares, to the payment of all amounts
      owing in respect of Deferred Interest, with net proceeds to be paid promptly
      after receipt until all amounts owing in respect of Deferred Interest have
      been
      paid in full. In the event that net proceeds received by the Company from one
      or
      more sales of shares of its common stock following such Fifth Deferral
      Anniversary are not sufficient to satisfy the full amount of Deferred Interest,
      such net proceeds will be paid to the holders of the Securities in chronological
      order; provided, that if the Company has outstanding at such time any debt
      securities ranking pari passu with the Securities under the terms of which
      the
      Company is obligated to sell shares of its common stock and apply the net
      proceeds to payment of deferred interest on such pari passu securities and
      the
      Company at such time is required to apply such proceeds to pay deferred interest
      on such pari passu securities, then on any date and for any period the amount
      of
      net proceeds received by the Company from such sales and available for payment
      of such deferred interest shall be applied on a pro rata basis to the amounts
      due on each series of such securities (including the Securities) up to any
      APM
      Maximum Obligation, Share Cap Amount or other similar limit then applicable
      to
      such series. Notwithstanding the above, the Company shall not be obligated
      to
      sell common stock or to apply such net proceeds or any portion thereof to the
      payment of Deferred Interest during the occurrence and continuation of Market
      Disruption Event or a Supervisory Event."

     

    
      
        
        

      

      
        6

        
          

        

      

      
        
        

      

    

     

    ARTICLE
      TWO

     

    Miscellaneous

     

    Section
      2.01 The
      Trustee accepts the modifications to Section 1.1, Section 2.3, Section 8.3,
      Section 13.3 and Section 13.5 of the Indenture set forth in this Second
      Supplemental Indenture upon the terms and conditions set forth in the Indenture.
      The Trustee shall not be responsible or accountable in any manner whatsoever
      for
      or in respect of, and makes no representation with respect to, the validity
      or
      sufficiency of this Second Supplemental Indenture or the due execution hereof
      by
      the Company and shall not be responsible in any manner whatsoever for or in
      respect of the correctness of the recitals and statements contained herein,
      all
      of which recitals and statements are made solely by the Company.

     

    Section
      2.02 Except
      as
      hereby expressly modified, the Indenture is in all respects ratified and
      confirmed and all the terms, conditions and provisions thereof shall remain
      in
      full force and effect. This Second Supplemental Indenture shall take effect
      on
      the date hereof. 

     

    Section
      2.03 This
      Second Supplemental Indenture may be executed in any number of counterparts,
      each of which shall be deemed to be an original for all purposes; but such
      counterparts shall together be deemed to constitute but one and the same
      instrument.

     

    
      
        
        

      

      
        7

        
          

        

      

      
        
        

      

    


    IN
      WITNESS WHEREOF, each of CITIGROUP INC. and THE BANK OF NEW YORK, as Trustee,
      has caused this Second Supplemental Indenture to be signed and acknowledged
      by
      one of its officers thereunto duly authorized, and its corporate seal to be
      affixed hereto, and the same to be attested by the signature of its Secretary
      or
      one of its Assistant Secretaries, all as of March 6, 2007.

     

    
      	 	 	 
	 	CITIGROUP
              INC.
	 
 	 
 	 
 
	 	By:  	/s/
              Charles E.
              Wainhouse
	 	Name: Charles E. Wainhouse
	 	Title:
              Assistant Treasurer


    

     

    
      	Attest: 	 	 
	 	 	 	 
	By: 	/s/
              Michael J. Tarpley 	 	 
	 	 	 	 
	Corporate Seal 	 	 


    

     

    
      	 	 	 
	 	THE
              BANK OF NEW YORK, as Trustee
	 
 	 
 	 
 
	Date: 	By:  	/s/
              James D. Heaney
	 	Name: James D. Heaney
	 	Title:
              Vice President


    

     

    
      	Attest: 	 	 
	 	 	 	 
	By: 	/s/
              Francine Kincaid	 	 
	 	 	 	 
	Corporate Seal 	 	 


    

     

    
      
        
        

      

      
        8