DEPOSIT AGREEMENT

EXHIBIT 4.3

MORGAN STANLEY,

JPMORGAN CHASE BANK, N.A.

AND

THE HOLDERS FROM TIME TO TIME OF

THE DEPOSITARY RECEIPTS DESCRIBED HEREIN

DEPOSIT AGREEMENT

Dated as of July 6, 2006

TABLE OF CONTENTS

ii

DEPOSIT AGREEMENT dated as of July 6, 2006, among MORGAN STANLEY, a Delaware corporation, JPMORGAN CHASE BANK, N.A., a national association organized pursuant to the laws of the United States, and the holders from time to time of the Receipts described herein.

WHEREAS, it is desired to provide as hereinafter set forth in this Deposit Agreement, for the deposit from time to time of shares of Floating Rate Non-Cumulative Preferred Stock, Series A (the “ Stock ”), par value $0.01 per share, liquidation preference $25,000 per share, of Morgan Stanley with the Depositary for the purposes set forth in this Deposit Agreement and for the issuance hereunder of Receipts evidencing Depositary Shares in respect of the Stock so deposited; and

WHEREAS, the Receipts are to be substantially in the form of Exhibit A annexed hereto, with appropriate insertions, modifications and omissions, as hereinafter provided in this Deposit Agreement;

NOW, THEREFORE, in consideration of the premises, the parties hereto agree as follows:

ARTICLE 1

D EFINITIONS

Section 1.01 . Definitions. The following definitions shall for all purposes, unless otherwise indicated, apply to the respective terms used in this Deposit Agreement:

“ Certificate ” shall mean the Certificate of Designation of Preferences and Rights filed or to be filed with the Secretary of State of the State of Delaware establishing the Stock as a series of preferred stock of the Company.

“ Company ” shall mean Morgan Stanley, a Delaware corporation, and its successors.

“ Deposit Agreement ” shall mean this Deposit Agreement, as amended or supplemented from time to time in accordance with the terms hereof.

“ Depositary ” shall mean JPMorgan Chase Bank, N.A., or any successor as Depositary hereunder.

“ Depositary Shares ” shall mean the depositary shares, each representing 1/1,000 ^th of a share of Stock and evidenced by a Receipt.

“ Depositary’s Agent ” shall mean an agent appointed by the Depositary pursuant to Section 7.05.

“ Depositary’s Office ” shall mean the principal corporate trust office of the Depositary in New York City, at which at any particular time its depositary receipt business shall be administered.

“ Exchange Event ” means with respect to the Global Registered Receipt: (A) the Global Receipt Depository which is the holder of such Global Registered Receipt or Receipts notifies the Company that it is no longer willing or able to properly discharge its responsibilities under the Letter of Representations or that it is no longer eligible or in good standing under the Securities Exchange Act of 1934, as amended, and (B) the Company has not appointed a qualified successor Global Receipt Depository within ninety (90) calendar days after the Company received such notice.

“ Global Receipt Depository ” means, with respect to any Receipt issued hereunder, The Depository Trust Company (“ DTC ”) or such other successor entity designated as Global Receipt Depository by the Company in or pursuant to this Deposit Agreement, which Person must be, to the extent required by any applicable law or regulation, a clearing agency registered under the Securities Exchange Act of 1934, as amended.

“ Global Registered Receipt ” means, with respect to the Depositary Shares, a global registered Receipt registered in the name of a nominee of the Global Receipt Depository.

“ Letter of Representations ” means the applicable agreement among the Company and a Global Receipt Depository with respect to such Global Receipt Depository’s rights and obligations with respect to the Global Registered Receipts, as the same may be amended, supplemented, restated or otherwise modified from time to time and any successor agreement thereto.

“ Holder, ” “ holder ” or “ record holder, ” as applied to a Receipt shall mean the person in whose name a Receipt is registered on the books of the Depositary maintained for such purpose.

“ Receipt ” shall mean one of the depositary receipts, substantially in the form set forth as Exhibit A hereto, issued hereunder, whether in definitive or temporary form and evidencing the number of Depositary Shares held of record by the holder of such Depositary Shares.

“ Redemption Date ” has the meaning set forth in Section 2.07.

“ Registrar ” shall mean the Depositary or such other successor bank or trust company that shall be appointed by the Company to register ownership and transfers of Receipts as herein provided, and if a Registrar shall be so appointed,

2

references herein to “the books” of or maintained by the Depositary shall be deemed, as applicable, to refer as well to the register maintained by such Registrar for such purpose.

“ Securities Act ” shall mean the Securities Act of 1933, as amended.

“ Stock ” shall mean shares of the Company’s Floating Rate Non-Cumulative Preferred Stock, Series A, par value $0.01 per share, liquidation preference $25,000 per share.

ARTICLE 2

F ORM OF R ECEIPTS , D EPOSIT OF S TOCK , E XECUTION AND D ELIVERY , T RANSFER ,

S URRENDER AND R EDEMPTION OF R ECEIPTS

Section 2.01 . Form and Transfer of Receipts. Definitive Receipts shall be engraved or printed or lithographed on steel-engraved borders, with appropriate insertions, modifications and omissions, as hereinafter provided. Pending the preparation of definitive Receipts, the Depositary, upon the written order of the Company delivered in compliance with Section 2.02, shall execute and deliver temporary Receipts that are printed, lithographed, typewritten, mimeographed or otherwise substantially of the tenor of the definitive Receipts in lieu of which they are issued and with such appropriate insertions, omissions, substitutions and other variations as the persons executing such Receipts may determine, as evidenced by their execution of such Receipts. If temporary Receipts are issued, the Company will cause definitive Receipts to be prepared without unreasonable delay. After the preparation of definitive Receipts, the temporary Receipts shall be exchangeable for definitive Receipts upon surrender of the temporary Receipts at an office described in the penultimate paragraph of Section 2.02, without charge to the holder. Upon surrender for cancellation of any one or more temporary Receipts, the Depositary shall execute and deliver in exchange therefor definitive Receipts representing the same number of Depositary Shares as are represented by the surrendered temporary Receipt or Receipts. Such exchange shall be made at the Company’s expense and without any charge therefor. Until so exchanged, the temporary Receipts shall in all respects be entitled to the same benefits under this Deposit Agreement, and with respect to the Stock, as definitive Receipts.

Receipts shall be executed by the Depositary by the manual or facsimile signature of a duly authorized officer of the Depositary and, if a Registrar for the Receipts shall have been appointed, countersigned by a duly authorized officer of the Registrar; provided that no Receipt shall be entitled to any benefits under this Deposit Agreement or be valid or obligatory for any purpose unless it shall have been executed manually by a duly authorized officer of the Depositary or, if a Registrar for the Receipts shall have been appointed, by manual or facsimile signature of a duly authorized officer of the Depositary and countersigned by a duly authorized officer of such Registrar. The Depositary shall record on its books each Receipt so signed and delivered as hereinafter provided.

3

Receipts shall be in denominations of any number of whole Depositary Shares.

Receipts may be endorsed with or have incorporated in the text thereof such legends or recitals or changes not inconsistent with the provisions of this Deposit Agreement as may be required by the Depositary or required to comply with any applicable law or any regulation thereunder or with the rules and regulations of any securities exchange upon which the Stock, the Depositary Shares or the Receipts may be listed or to conform with any usage with respect thereto, or to indicate any special limitations or restrictions to which any particular Receipts are subject.

Title to Depositary Shares evidenced by a Receipt that is properly endorsed or accompanied by a properly executed instrument of transfer shall be transferable by delivery with the same effect as in the case of a negotiable instrument; provided, however, that until transfer of a Receipt shall be registered on the books of the Depositary as provided in Section 2.03, the Depositary may, notwithstanding any notice to the contrary, treat the holder of record at such time as the absolute owner thereof for the purpose of determining the person entitled to distributions of dividends or other distributions or to any notice provided for in this Deposit Agreement and for all other purposes.

Section 2.02 . Deposit of Stock; Execution and Delivery of Receipts in Respect Thereof. Subject to the terms and conditions of this Deposit Agreement, the Company may from time to time deposit shares of Stock under this Deposit Agreement by delivery to the Depositary of a certificate or certificates for the Stock to be deposited, properly endorsed or accompanied, if required by the Depositary, by a duly executed instrument of transfer or endorsement, in form satisfactory to the Depositary, together with all such certifications as may be required by the Depositary in accordance with the provisions of this Deposit Agreement, and together with a written order of the Company directing the Depositary to execute and deliver to, or upon the written order of, the person or persons stated in such order a Receipt or Receipts for the number of Depositary Shares representing such deposited Stock.

Deposited Stock shall be held by the Depositary at the Depositary’s Office or at such other place or places as the Depositary shall determine.

Upon receipt by the Depositary of a certificate or certificates for Stock deposited in accordance with the provisions of this Section, together with the other documents required as above specified, and upon recordation of the Stock on the books of the Company (or its duly appointed transfer agent) in the name of the Depositary or its nominee, the Depositary, subject to the terms and conditions of this Deposit Agreement, shall execute and deliver, to or upon the order of the person or persons named in the written order delivered to the Depositary referred to in the first paragraph of this Section, a Receipt or Receipts for the number of Depositary Shares representing the Stock so deposited and registered in such

4

name or names as may be requested by such person or persons. The Depositary shall execute and deliver such Receipt or Receipts at the Depositary’s Office or such other offices, if any, as the Depositary may designate. Delivery at other offices shall be at the risk and expense of the person requesting such delivery.

Notwithstanding the foregoing, pending preparation by the Company of definitive certificates for the Stock to be deposited, the Company may deliver temporary certificates for Stock that are printed, lithographed, typewritten, mimeographed or otherwise substantially of the tenor of the definitive certificates for Stock in lieu of which they are issued and with such appropriate insertions, omissions, substitutions and other variations as the Company may determine. If temporary certificates for Stock are delivered, the Company will cause definitive certificates for Stock to be prepared without unreasonable delay. After the preparation of definitive certificates for Stock, the temporary certificates for Stock shall be exchangeable for definitive certificates for Stock upon surrender of the temporary certificates for Stock at the Depositary’s Office, without charge to the Depositary.

Section 2.03 . Registration of Transfer of Receipts. Subject to the terms and conditions of this Deposit Agreement, including payment of the fees of the Depositary as provided in Section 5.07, the Depositary shall register on its books from time to time transfers of Receipts upon any surrender thereof by the holder in person or by duly authorized attorney, properly endorsed or accompanied by a properly executed instrument of transfer. Thereupon the Depositary shall execute a new Receipt or Receipts evidencing the same aggregate number of Depositary Shares as those evidenced by the Receipt or Receipts surrendered and deliver such new Receipt or Receipts to or upon the order of the person entitled thereto.

The Depositary shall not be required (a) to issue, transfer or exchange any Receipts for a period beginning at the opening of business fifteen days next preceding any selection of Depositary Shares and Stock to be redeemed and ending at the close of business on the day of the mailing of notice of redemption, or (b) to transfer or exchange for another Receipt any Receipt called or being called for redemption in whole or in part except as provided in Section 2.07.

Section 2.04 . Split-ups and Combinations of Receipts; Surrender of Receipts and Withdrawal of Stock. Upon surrender of a Receipt or Receipts at the Depositary’s Office or at such other offices as it may designate for the purpose of effecting a split-up or combination of such Receipt or Receipts, and subject to the terms and conditions of this Deposit Agreement, the Depositary shall execute and deliver a new Receipt or Receipts in the authorized denomination or denominations requested, evidencing the aggregate number of Depositary Shares evidenced by the Receipt or Receipts surrendered.

Any holder of a Receipt or Receipts representing any number of whole shares of Stock may withdraw the Stock and all money and other property, if any, represented thereby by surrendering such Receipt or Receipts at the Depositary’s

5

Office or at such other offices as the Depositary may designate for such withdrawals. Upon payment of the fees of the Depositary for the withdrawal of Stock as provided in Section 5.07 and payment of all taxes and without unreasonable delay, the Depositary shall deliver to such holder or to the person or persons designated by such holder as hereinafter provided, the number of whole shares of Stock and all money and other property, if any, represented by the Depositary Shares evidenced by the Receipt or Receipts so surrendered for withdrawal, but holders of such whole shares of Stock will not thereafter be entitled to deposit such Stock hereunder or to receive Depositary Shares therefor or a Receipt evidencing such Depositary Shares. If a Receipt delivered by the holder to the Depositary in connection with such withdrawal shall evidence a number of Depositary Shares in excess of the number of Depositary Shares representing the number of whole shares of Stock to be so withdrawn, the Depositary shall at the same time, in addition to such number of whole shares of Stock and such money and other property, if any, to be so withdrawn, deliver to such holder, or pursuant to his order, upon payment of the fees of the Depositary for the withdrawal of Stock as provided in Section 5.07 and payment of all taxes, a new Receipt evidencing such excess number of Depositary Shares. Delivery of the Stock and money and other property, if any, being withdrawn may be made by the delivery of such certificates, documents of title and other instruments as the Depositary may deem appropriate.

If the Stock and the money and other property, if any, being withdrawn are to be delivered to a person or persons other than the holder of the Receipt or Receipts being surrendered for withdrawal of Stock, such holder shall execute and deliver to the Depositary a written order so directing the Depositary and the Depositary may require that the Receipt or Receipts surrendered by such holder for the withdrawal of such shares of Stock be properly endorsed in blank or accompanied by a properly executed instrument of transfer in blank.

Delivery of the Stock and the money and other property, if any, represented by Receipts surrendered for withdrawal shall be made by the Depositary at the Depositary’s Office, except that, at the request, risk and expense of the holder surrendering such Receipt or Receipts and for the account of the holder thereof, such delivery may be made at such other place as may be designated by such holder.

Section 2.05 . Limitations on Execution and Delivery, Transfers, Surrender and Exchange of Receipts. As a condition precedent to the execution and delivery, registration of transfer, split-up, combination, surrender or exchange of any Receipt, the Depositary, any of the Depositary’s Agents or the Company may require payment to it of a sum sufficient for the payment (or, in the event that the Depositary or the Company shall have made such payment, the reimbursement to it) of any charges or expenses payable by the holder of a Receipt pursuant to Section 5.07, may require the production of evidence satisfactory to it as to the identity and genuineness of any signature and may also require compliance with

6

such regulations, if any, as the Depositary or the Company may establish consistent with the provisions of this Deposit Agreement and/or applicable law.

The deposit of Stock may be refused, the delivery of Receipts against Stock may be suspended, the registration of transfer of Receipts may be refused and the registration of transfer, surrender or exchange of outstanding Receipts may be suspended (i) during any period when the register of stockholders of the Company is closed or (ii) if any such action is deemed necessary or advisable by the Depositary, any of the Depositary’s Agents or the Company at any time or from time to time because of any requirement of law or of any government or governmental body or commission or under any provision of this Deposit Agreement.

Section 2.06 . Lost Receipts, Etc. In case any Receipt shall be mutilated, destroyed, lost or stolen, the Depositary in its discretion may execute and deliver a Receipt of like form and tenor in exchange and substitution for such mutilated Receipt upon cancellation thereof, or in lieu of and in substitution for such destroyed, lost or stolen Receipt. Before the Depositary shall execute and deliver a new Receipt in substitution for a destroyed, lost or stolen Receipt, the holder thereof shall have (i) delivered to the Depositary (a) a request for such execution and delivery prior to the Depositary having received notice that the Receipt has been acquired by a bona fide purchaser, (b) evidence satisfactory to the Depositary of such destruction, loss or theft of such Receipt and of ownership thereof and (c) indemnification satisfactory to the Depositary and (ii) satisfied any other reasonable requirements imposed by the Depositary.

Section 2.07 . Optional Redemption of Stock. If the Company shall elect to redeem shares of Stock pursuant to the Certificate, it shall (unless otherwise agreed to in writing with the Depositary) give the Depositary not less than 30 days’ notice of the date of such proposed redemption of Stock, the number of shares of Stock held by the Depositary to be redeemed and the redemption price per share of Stock. The Depositary shall be fully protected and shall incur no liability in its reliance on the information contained in such notice and delivery of such notice to the Depositary shall be conclusive evidence of the permissibility and compliance of such redemption under the Certificate. On the date of such redemption, provided that the Company shall then have paid or caused to be paid in full to the Depositary the redemption price (determined pursuant to the Certificate) of the Stock deposited with the Depositary to be redeemed, the Depositary shall redeem (using the proceeds of such redemption) the Depositary Shares relating to such Stock. The Depositary shall mail, first class postage prepaid, notice of the Company’s redemption of Stock and the proposed simultaneous redemption of the Depositary Shares relating to the Stock to be redeemed, not less than 15 days and not more than 60 days prior to the date fixed for redemption of such Stock and Depositary Shares (the “ Redemption Date ”), to the holders on the record date fixed for such redemption pursuant to Section 4.04 of the Receipts evidencing the Depositary Shares to be so redeemed, at the addresses of such holders as the same appear on the records of the Depositary; but

7

neither failure to mail any such notice to one or more such holders nor any defect in any notice shall affect the sufficiency of the proceedings for redemption as to the other holders. The Company shall provide the Depositary with such notice, and each such notice shall state: (i) the Redemption Date; (ii) the number of Depositary Shares to be redeemed and, if fewer than all the Depositary Shares held by any holder are to be redeemed, the number of Depositary Shares held by such holder to be so redeemed; (iii) the redemption price and (iv) the place or places where Receipts evidencing Depositary Shares to be redeemed are to be surrendered for payment of the redemption price. In case fewer than all the outstanding Depositary Shares are to be redeemed, the Depositary Shares to be redeemed shall be selected pro rata (as nearly as may be), or by any other method as determined by the Company to be fair and equitable in its sole discretion.

Notice having been mailed by the Depositary as aforesaid, from and after the Redemption Date (unless the Company shall have failed to redeem the shares of Stock to be redeemed by it as set forth in the Company’s notice provided for in the preceding paragraph) all dividends in respect of the shares of Stock called for redemption shall cease to accrue, the Depositary Shares called for redemption shall be deemed no longer to be outstanding and all rights of the holders of Receipts evidencing such Depositary Shares (except the right to receive the redemption price) shall, to the extent of such Depositary Shares, cease and terminate. Upon surrender in accordance with said notice of the Receipts evidencing such Depositary Shares (properly endorsed or assigned for transfer, if the Depositary shall so require), such Depositary Shares shall be redeemed at a redemption price per Depositary Share equal to one-one thousandth of the redemption price per share paid in respect of shares of Stock pursuant to the Certificate plus all money and other property, if any, represented by such Depositary Shares, including all amounts paid by the Company in respect of dividends that on the Redemption Date have accrued on the shares of Stock to be so redeemed and that have not theretofore been paid. The foregoing shall be subject further to the terms and conditions of the Certificate.

If fewer than all of the Depositary Shares evidenced by a Receipt are called for redemption, the Depositary will deliver to the holder of such Receipt upon its surrender to the Depositary, together with payment of the redemption price for the Depositary Shares called for redemption, a new Receipt evidencing the Depositary Shares evidenced by such prior Receipt and not called for redemption.

Except as provided in the preceding paragraph of this Section 2.07, the Depositary shall not be required to transfer or exchange for another Receipt any Receipt evidencing Depositary Shares called or being called for redemption in whole or in part.

The Depositary shall remit to the Company any funds deposited by or for the account of the Company for the purpose of redeeming any Depositary Shares

8

that the holders thereof have failed to redeem after two years from the date of such deposit, without further action necessary on the part of the Company.

Section 2.08 . Cancellation and Destruction of Surrendered Receipts. All Receipts surrendered to the Depositary or any Depositary’s Agent shall be cancelled by the Depositary. Except as prohibited by applicable law or regulation, the Depositary is authorized to destroy all Receipts so cancelled.

Section 2.09 . Receipts Issuable in Global Registered Form. If the Company shall determine in a writing delivered to the Depositary that the Receipts are to be issued in whole or in part in the form of one or more Global Registered Receipts, then the Depositary shall, in accordance with the other provisions of this Deposit Agreement, execute and deliver one or more Global Registered Receipts evidencing the Receipts, which (i) shall represent, and shall be denominated in an amount equal to the aggregate liquidation preference of, the Receipts to be represented by such Global Registered Receipt or Receipts, and (ii) shall be registered in the name of the Global Receipt Depository therefor or its nominee.

Notwithstanding any other provision of this Deposit Agreement to the contrary, unless otherwise provided in a Global Registered Receipt, such Global Registered Receipt may only be transferred in whole and only by the Global Receipt Depository to its nominee, or by such nominee to the Global Receipt Depository or to another nominee of the Global Receipt Depository, or by the Global Receipt Depository or any nominee thereof to a successor Global Receipt Depository for the Global Registered Receipt selected or approved by the Company or to a nominee of the Global Receipt Depository. Except as provided below, owners solely of beneficial interests in a Global Registered Receipt shall not be entitled to receive physical delivery of the Receipts represented by such Global Registered Receipt. Neither any such beneficial owner nor any direct or indirect participant of a Global Receipt Depository shall have any rights under this Deposit Agreement with respect to any Global Registered Receipt held on their behalf by a Global Receipt Depository and such Global Receipt Depository may be treated by the Company, the Depositary and any director, officer, employee or agent of the Company or the Depositary as the holder of such Global Registered Receipt for all purposes whatsoever. Unless and until definitive Receipts are delivered to the owners of the beneficial interests in a Global Registered Receipt, (1) the Global Receipt Depository will make book-entry transfers among its participants and receive and transmit all payments and distributions in respect of Global Registered Receipts to such participants, in each case, in accordance with its applicable procedures and arrangements, and (2) whenever any notice, payment or other communication to the holders of Global Registered Receipts is required under this Deposit Agreement, the Company and the Depositary shall give all such notices, payments and communications specified herein to be given to such holders to the Global Receipt Depository.

9

If an Exchange Event has occurred with respect to any Global Registered Receipt, then, in any such event, the Depositary shall, upon receipt of a written order from the Company for the execution and delivery of individual definitive registered Receipts in exchange for such Global Registered Receipt, execute and deliver, individual definitive registered Receipts, in authorized denominations and of like tenor and terms in an aggregate liquidation preference equal to the liquidation preference of the Global Registered Receipt in exchange for such Global Registered Receipt.

Definitive registered Receipts issued in exchange for a Global Registered Receipt pursuant to this Section shall be registered in such names and in such authorized denominations as the Global Receipt Depository, pursuant to instructions from its participants, shall instruct the Depositary in writing. The Depositary shall deliver such Receipts to the persons in whose names such Receipts are so registered.

Notwithstanding anything to the contrary in this Deposit Agreement, should the Company determine that the Receipts should be issued as a Global Registered Receipt, or that a Global Registered Receipt should be issued in exchange for definitive registered Receipts, the parties hereto shall comply with the terms of the Letter of Representations.

ARTICLE 3

C ERTAIN O BLIGATIONS OF H OLDERS OF R ECEIPTS AND THE C OMPANY

Section 3.01 . Filing Proofs, Certificates and Other Information. Any holder of a Receipt may be required from time to time to file such proof of residence, or other matters or other information, to execute such certificates and to make such representations and warranties as the Depositary or the Company may reasonably deem necessary or proper. The Depositary or the Company may withhold the delivery, or delay the registration of transfer, redemption or exchange, of any Receipt or the withdrawal of the Stock represented by the Depositary Shares evidenced by any Receipt or the distribution of any dividend or other distribution or the sale of any property or rights or of the proceeds thereof until such proof or other information is filed or such certificates are executed or such representations and warranties are made.

Section 3.02 . Payment of Taxes or Other Governmental Charges. Holders of Receipts shall be obligated to make payments to the Depositary of certain charges and expenses, as provided in Section 5.07. Registration of transfer of any Receipt or any withdrawal of Stock and all money or other property, if any, represented by the Depositary Shares evidenced by such Receipt may be refused until any such payment due is made, and any dividends, interest payments or other distributions may be withheld or any part of or all the Stock or other property represented by the Depositary Shares evidenced by such Receipt and not theretofore sold may be sold for the account of the holder thereof (after

10

attempting by reasonable means to notify such holder prior to such sale), and such dividends, interest payments or other distributions or the proceeds of any such sale may be applied to any payment of such charges or expenses, the holder of such Receipt remaining liable for any deficiency.

Section 3.03 . Warranty as To Stock. The Company hereby represents and warrants that the Stock, when issued, will be duly authorized, validly issued, fully paid and nonassessable. Such representation and warranty shall survive the deposit of the Stock and the issuance of Receipts.

ARTICLE 4

T HE D EPOSITED S ECURITIES ; N OTICES

Section 4.01 . Cash Distributions . Whenever the Depositary shall receive any cash dividend or other cash distribution on Stock, the Depositary shall, subject to Sections 3.01 and 3.02, distribute to holders of Receipts on the record date fixed pursuant to Section 4.04 (net of the fees of the Depositary as provided in Section 5.07 hereof) such a