EXHIBIT 4(a)

                            SUPPLEMENTAL INDENTURE





                           MERRILL LYNCH & CO., INC.

                                      AND

                          JPMORGAN CHASE BANK, N.A.,
                                  as Trustee




                       --------------------------------

                            SUPPLEMENTAL INDENTURE

                           Dated as of May 16, 2006

                       --------------------------------







                            Supplement to Indenture
                         Dated as of December 17, 1996

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      Supplemental Indenture, dated as of May 16, 2006 (the "Supplemental
Indenture"), by and between Merrill Lynch & Co., Inc., a corporation organized
and existing under the laws of the State of Delaware, having its principal
office at 4 World Financial Center, New York, New York 10080 (the "Company"),
and JPMorgan Chase Bank, N.A., successor to The Chase Manhattan Bank, a
national banking association duly organized and existing under the laws of the
United States of America and having its Corporate Trust Office at 4 New York
Plaza, 15th Floor, New York, New York 10004, as trustee (the "Trustee").

      WHEREAS, the Company has heretofore executed and delivered its
Indenture, dated as of December 17, 1996 (the "Principal Indenture"), to the
Trustee to provide for the issuance from time to time of its subordinated debt
securities (the "Securities"), unlimited as to principal amount; and

      WHEREAS, the Principal Indenture and this Supplemental Indenture are
hereinafter collectively referred to as the "Indenture"; and

      WHEREAS, Section 901 of the Principal Indenture provides that, without
the consent of any Holders, the Company, when authorized by a Board
Resolution, and the Trustee, at any time and from time to time, may enter into
one or more indentures supplemental to the Principal Indenture, in form
satisfactory to the Trustee, to make any provisions with respect to matters or
questions arising under the Principal Indenture which shall not be
inconsistent with the provisions of the Principal Indenture and which shall
not adversely affect the interests of the Holders of Securities of any series
or any related coupons in any material respect; and

      WHEREAS, the Company has duly authorized the execution and delivery of
this Supplemental Indenture, and all things necessary to make this
Supplemental Indenture a valid agreement of the Company, in accordance with
its terms, have been done;

      NOW, THEREFORE, the Company and the Trustee, in consideration of the
premises and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, hereby covenant and agree, for
the equal and proportionate benefit of all Holders of the Securities, as
follows:

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                                      I.

               AMENDMENT OF CERTAIN PROVISIONS OF THE INDENTURE

      Section 101. Amendment of Section 101 of Principal Indenture. Section
101 of the Principal Indenture is hereby amended, with respect to all series
of Securities issued on or after the date hereof, as follows:

      (a) By deleting in its entirety the definition of "Company" contained
therein and inserting in its stead the following:

      "`Company' means the Person named as the `Company' in the first
paragraph of this instrument until a successor Person shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
`Company' shall mean such successor Person."

      (b) By deleting in its entirety the definition of "Company Request" and
"Company Order" contained therein and inserting in its stead the following:

      "`Company Request' and `Company Order' mean, respectively, a written
request or order signed in the name of the Company by the Chairman of the
Board, the President, a Vice President, the Treasurer or an Assistant
Treasurer, and by the Secretary or an Assistant Secretary of the Company, and
delivered to the Trustee."

      (c) By deleting in its entirety the definition of "Controlled
Subsidiary" contained therein.

      (d) By deleting in its entirety the definition of "Officers'
Certificate" contained therein and inserting in its stead the following:

      "`Officers' Certificate' means a certificate signed by the Chairman of
the Board, the President, a Vice President, the Treasurer or an Assistant
Treasurer, and by the Secretary or an Assistant Secretary of the Company, and
delivered to the Trustee."

      (e) By deleting in its entirety the definition of "Person" contained
therein and inserting in its stead the following:

      "`Person' means any individual, corporation, partnership, joint venture,
association, limited liability company, joint-stock company, trust,
unincorporated organization or government or any agency or political
subdivision thereof."

      (f) By deleting in its entirety the definition of "Subsidiary" contained
therein.

      (g) By deleting in its entirety the definition of "Voting Stock"
contained therein.

      Section 102. Amendment of Section 303 of Principal Indenture. Section
303 of the Principal Indenture is hereby amended, with respect to all series
of Securities issued on or after


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the date hereof, by deleting in its entirety the first sentence of such
Section and inserting in its stead the following:

      "The Securities shall be executed on behalf of the Company by its
Chairman of the Board, President, Vice President serving as Chief Financial
Officer or its Treasurer or Assistant Treasurer under its corporate seal
reproduced thereon and attested by its Secretary or one of its Assistant
Secretaries."

      Section 103. Amendment of Section 501 of Principal Indenture. Section
501 of the Principal Indenture is hereby amended, with respect to all series
of Securities issued on or after the date hereof, by deleting in its entirety
the portion of the definition of "Event of Default" prior to the numbered
items and inserting in its stead the following:

      "`Event of Default', wherever used herein with respect to Securities of
any series, means, unless provided for otherwise with respect to Securities of
such Series (in or pursuant to a Board Resolution, and set forth in an
Officer's Certificate, or in one or more indentures supplemental hereto), 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 pursuant to any judgment, decree or order of any court or any order, rule
or regulation of any administrative or governmental body):"

      Section 104. Amendment of Section 801 of Principal Indenture. Section
801 of the Principal Indenture is hereby amended, with respect to all series
of Securities issued on or after the date hereof, by deleting it in its
entirety and inserting in its stead the following:

      "SECTION 801. Consolidations and Mergers of Company and Sales, Leases
and Conveyances Permitted Subject to Certain Conditions.

      The Company may consolidate with, or sell, lease or convey all or
substantially all of its assets to, or merge with or into any other Person,
provided that in any such case, (i) either the Company shall be the continuing
Person, or the successor Person shall be a Person organized and existing under
the laws of the United States of America or a State thereof and such successor
Person shall expressly assume the due and punctual payment of the principal of
(and premium, if any), any interest on, and any Additional Amounts payable
pursuant to Section 1004 with respect to, all the Securities, according to
their tenor, and the due and punctual performance and observance of all the
covenants and conditions of this Indenture to be performed by the Company by
supplemental indenture satisfactory to the Trustee, executed and delivered to
the Trustee by such Person, and (ii) the Company or such successor Person, as
the case may be, shall not, immediately after such merger or consolidation, or
such sale, lease or conveyance, be in default in the performance of any such
covenant or condition."

      Section 105. Amendment of Section 802 of Principal Indenture. Section
802 of the Principal Indenture is hereby amended, with respect to all series
of Securities issued on or after the date hereof, by deleting it in its
entirety and inserting in its stead the following:


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      "SECTION 802. Rights and Duties of Successor Person.

      In case of any such consolidation, merger, sale, lease or conveyance and
upon any such assumption by the successor Person, such successor Person shall
succeed to and be substituted for the Company, with the same effect as if it
had been named herein as the party of the first part, and the predecessor
Person, except in the event of a lease, shall be relieved of any further
obligation under this Indenture and the Securities and coupons. Such successor
Person thereupon may cause to be signed, and may issue either in its own name
or in the name of the Company, any or all of the Securities and coupons
issuable hereunder which theretofore shall not have been signed by the Company
and delivered to the Trustee; and, upon the order of such successor Person,
instead of the Company, and subject to all the terms, conditions and
limitations in this Indenture prescribed, the Trustee shall authenticate and
shall deliver any Securities and coupons which previously shall have been
signed and delivered by the officers of the Company to the Trustee for
authentication, and any Securities or coupons which such successor Person
thereafter shall cause to be signed and delivered to the Trustee for that
purpose. All the Securities and coupons so issued shall in all respects have
the same legal rank and benefit under this Indenture as the Securities and
coupons theretofore or thereafter issued in accordance with the terms of this
Indenture as though all of such Securities and coupons had been issued at the
date of the execution hereof.

      In case any of such consolidation, merger, sale, lease or conveyance,
such changes in phraseology and form (but not in substance) may be made in the
Securities and coupons thereafter to be issued as may be appropriate."

                                     II.

                                 MISCELLANEOUS

      Section 201. Effect of Supplemental Indenture. The Principal Indenture,
as supplemented and amended by this Supplemental Indenture and all other
indentures supplemental thereto, is in all respects ratified and confirmed,
and the Principal Indenture, this Supplemental Indenture and all indentures
supplemental thereto shall be read, taken and construed as one and the same
instrument.

      Section 202. Conflict with Trust Indenture Act. If any provision hereof
limits, qualifies or conflicts with another provision hereof which is required
or deemed to be included in this Supplemental Indenture by any of the
provisions of the Trust Indenture Act, such required or deemed included
provision shall control.

      Section 203. Definitions. Capitalized terms used in the Principal
Indenture and in this Supplemental Indenture, but not defined herein, are used
as they are defined in the Principal Indenture.

      Section 204. Successors and Assigns. All covenants and agreements in
this Supplemental Indenture by the Company shall bind its successors and
assigns, whether so expressed or not.

      Section 205. Separability Clause. In case any provision in this
Supplemental Indenture shall be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining


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provisions (or of the other series of Securities) shall not in any way be
affected or impaired thereby.

      Section 206. Benefits of Supplemental Indenture. Nothing in this
Supplemental Indenture, express or implied, shall give to any Person, other
than the parties hereto and their successors hereunder and any Holders of
Securities or coupons, any benefit or any legal or equitable right, remedy or
claim under this Supplemental Indenture.

      Section 207. Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE DEEMED
TO BE A CONTRACT MADE UNDER THE LAWS OF THE STATE OF NEW YORK AND THIS
SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF NEW YORK.

      Section 208. Execution in 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 209. Responsibility for Recitals. The recitals contained herein
shall be taken as statements of the Company, and the Trustee assumes no
responsibility for their correctness. The Trustee makes no representations as
to the validity or sufficiency of the Principal Indenture or this Supplemental
Indenture.

      Section 210. Effectiveness of Supplemental Indenture. The Company and
the Trustee hereby agree that this Supplemental Indenture shall take effect on
May 16, 2006.


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      IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed, all as of the day and year first above written.



                                              MERRILL LYNCH & CO., INC.


                                              By:  ____________________________
                                                    Name:
                                                    Title:


                                              [SEAL]


                                              Attest:  ________________________
                                                    Name:
                                                    Title:


                                              JPMORGAN CHASE BANK, N.A.,
                                              as Trustee


                                              By:
                                                    Name:
                                                    Title: