UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   Form 11-K

    (Mark One)

  [X]   ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE
        SECURITIES EXCHANGE ACT OF 1934


                  For the fiscal year ended December 31, 2006

                                      OR

  [ ]   TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE
        SECURITIES EXCHANGE ACT OF 1934


             For the transition period from __________ to __________


                        Commission file number 1-15403


   A.   Full title of the plan and the address of the plan, if different
        from that of the Issuer named below:

          Missouri State Bank & Trust Company Retirement Savings Plan

   B.   Name of the issuer of the securities held pursuant to the plan and
        the address of its principal executive office:

                         MARSHALL & ILSLEY CORPORATION
                            770 North Water Street
                           Milwaukee, Wisconsin 53202

Financial Statement and Exhibits
--------------------------------

  (a) Financial Statements:
      ---------------------

         Missouri State Bank & Trust Company Retirement Savings Plan
         -----------------------------------------------------------
            Report of Independent Registered Public Accounting Firm.
            Statements of Net Assets Available for Benefits
               as of December 31, 2006 and 2005.
            Statements of Changes in Net Assets Available for Benefits
               for the Year Ended December 31, 2006.
            Notes to Financial Statements as of December 31, 2006 and
               2005 and for the Year Ended December 31, 2006.
            Supplemental Schedule, Form 5500, Schedule H,
               Part IV, Line 4(i)
                  Schedule of Assets (Held at End of Year)
                  as of December 31, 2006.

  (b) Exhibits:
      ---------

         23 Consent of Independent Registered Public Accounting Firm -
               Deloitte & Touche LLP


Missouri State Bank & Trust Company Retirement Savings Plan

Financial Statements as of December 31, 2006
and for the Year Ended December 31, 2006,
Supplemental Schedule as of December 31, 2006,
and Report of Independent Registered Public Accounting Firm


MISSOURI STATE BANK & TRUST COMPANY RETIREMENT SAVINGS PLAN

TABLE OF CONTENTS
-----------------

                                                  Page

REPORT OF INDEPENDENT REGISTERED
   PUBLIC ACCOUNTING FIRM                          1

FINANCIAL STATEMENTS:
 Statements of Net Assets Available for
   Benefits as of December 31, 2006 and 2005       2

 Statements of Changes in Net Assets
   Available for Benefits for the
    Year Ended December 31, 2006                   3

 Notes to Financial Statements as of
   December 31, 2006 and 2005 and for
   the Year Ended December 31, 2006             4-10

SUPPLEMENTAL SCHEDULE -                           11

 Form 5500, Schedule H, Part IV, Line 4i --
   Schedule of Assets (Held at End of Year)
     as of December 31, 2006                      12


NOTE: All other schedules required by Section 2520.103-10
      of the Department of Labor's Rules and Regulations
      for Reporting and Disclosure under the Employee
      Retirement Income Security Act of 1974 have been
      omitted because they are not applicable.


              [Deloitte & Touche LLP Letterhead]

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Trustee and Participants of the
Missouri State Bank & Trust Company Retirement Savings Plan:

We have audited the accompanying statements of net assets available for
benefits of the Missouri State Bank & Trust Company Retirement Savings Plan
(the "Plan") as of December 31, 2006 and 2005, and the related statement of
changes in net assets available for benefits for the year ended December
31, 2006. These financial statements are the responsibility of the Plan's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with standards of the Public Company
Accounting Oversight Board (United States). Those standards require that we
plan and perform the audit to obtain reasonable assurance about whether the
financial statements are free of material misstatement. The Plan is not
required to have, nor were we engaged to perform, an audit of its internal
control over financial reporting. Our audits included consideration of
internal control over financial reporting as a basis for designing audit
procedures that are appropriate in the circumstances, but not for the
purpose of expressing an opinion on the effectiveness of the Plan's
internal control over financial reporting. Accordingly, we express no such
opinion. An audit also includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements,
assessing the accounting principles used and significant estimates made by
management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, such financial statements present fairly, in all material
respects, the net assets available for benefits of the Plan as of December
31, 2006 and 2005, and the changes in net assets available for benefits for
the year ended December 31, 2006, in conformity with accounting principles
generally accepted in the United States of America.

Our audits were conducted for the purpose of forming an opinion on the
basic financial statements taken as a whole. The supplemental schedule of
assets (held at end of year) as of December 31, 2006, is presented for the
purpose of additional analysis and is not a required part of the basic
financial statements, but is supplementary information required by the
Department of Labor's Rules and Regulations for Reporting and Disclosure
under the Employee Retirement Income Security Act of 1974. This schedule is
the responsibility of the Plan's management. Such schedule has been
subjected to the auditing procedures applied in our audit of the basic 2006
financial statements and, in our opinion, is fairly stated in all material
respects when considered in relation to the basic 2006 financial statements
taken as a whole.


/s/ Deloitte & Touche


Milwaukee, Wisconsin
June 22, 2007

 2
MISSOURI STATE BANK & TRUST COMPANY RETIREMENT SAVINGS PLAN

STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS
AS OF DECEMBER 31, 2006 AND 2005


                                         2006            2005
                                   --------------- ---------------
                                            
ASSETS:

  Investments -- at fair value:
    Master Trusts                  $      833,030  $          --
    Investments                         2,333,878       3,253,134
    Loans to participants                  11,735          21,848
                                    --------------  --------------
        Total investments               3,178,643       3,274,982

RECEIVABLES:
  Employer contribution                       --           16,692
  Employee contributions                      --            5,825
  Accrued investment income                 1,304             --
                                    --------------  --------------
        Total receivables                   1,304          22,517
                                    --------------  --------------
        Total assets                    3,179,947       3,297,499

LIABILITIES -- Payables --
  pending trades                            1,535             --
                                    --------------  --------------
NET ASSETS AVAILABLE FOR
  BENEFITS AT FAIR VALUE                3,178,412       3,297,499

Adjustments from fair value to
  contract value for fully benefit-
  responsive investment contacts            2,992             --
                                    --------------  --------------
NET ASSETS AVAILABLE FOR BENEFITS  $    3,181,404  $    3,297,499
                                    ==============  ==============

See notes to financial statements.


 3
MISSOURI STATE BANK & TRUST COMPANY RETIREMENT SAVINGS PLAN

STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS
FOR THE YEAR ENDED DECEMBER 31, 2006


                                               
CONTRIBUTIONS:
  Participants                                     $      163,108
  Employer                                                 38,764
  Participant rollovers                                     1,783
                                                    --------------
        Total contributions                               203,655
                                                    --------------

INVESTMENT INCOME:
  Income from Master Trusts                                68,457
  Net appreciation of
    fair value of investments                             328,495
  Interest                                                 17,245
                                                    --------------
        Net investment income                             414,197
                                                    --------------

DEDUCTIONS:
  Benefits paid to participants                          (732,345)
  Administrative expenses                                  (1,602)
                                                    --------------
        Total deductions                                 (733,947)
                                                    --------------

NET DECREASE IN ASSETS AVAILABLE FOR BENEFITS            (116,095)

NET ASSETS AVAILABLE FOR BENEFITS:
  Beginning of year                                     3,297,499
                                                    --------------
  End of year                                      $    3,181,404
                                                    ==============

See notes to financial statements.


 4
MISSOURI STATE BANK & TRUST COMPANY RETIREMENT SAVINGS PLAN

NOTES TO FINANCIAL STATEMENTS
AS OF DECEMBER 31, 2006 AND 2005, AND FOR THE YEAR ENDED DECEMBER 31, 2006

  1.  DESCRIPTION OF THE PLAN

      The following description of the Missouri State Bank & Trust Company
      Retirement Savings Plan (the "Plan") is provided for general
      information purposes only.  Participants should refer to the Plan
      document for more complete information.

      General -- The Plan is a defined contribution plan covering
      substantially all salaried employees of Missouri State Bank & Trust
      Company (the "Company").  Marshall & Ilsley Corporation (the
      "Corporation") is the administrator of the Plan and Marshall & Ilsley
      Trust Company (the "Trustee"), a subsidiary of the Corporation,
      serves as the trustee of the Plan. Prior to the Company's merger with
      the Corporation, described below, the Company served as administrator
      and trustee of the Plan. The Plan is subject to the provisions of the
      Employee Retirement Income Security Act of 1974, as amended (ERISA).

      On April 1, 2006, the Company merged with the Corporation and
      participants terminated as a direct result of the merger became 100%
      vested in the Plan.  Participants continuing with the Corporation
      post merger are subject to the vesting schedule of the Plan as
      described below. The Plan's benefits were frozen as of April 30,
      2006.

      Effective April 1, 2006, each Plan participant was eligible to make
      the election to participate in the M&I Retirement Plan, a defined
      contribution plan which is subject to the provisions of ERISA.

      Contributions -- Prior to the Plan being frozen, participants could
      elect to contribute 1% to 15% of their pretax annual compensation, as
      defined in the Plan, subject to certain Internal Revenue Code (IRC)
      limitations.  The Company also made discretionary matching
      contributions equal to a percentage of participants elective deferral
      contributions. Participants could also contribute amounts
      representing distributions from other qualified defined benefit or
      defined contribution plans.

      Participant Accounts -- Individual accounts are maintained for each
      Plan participant. Each participant's account is credited with the
      participant's contribution, the Company's matching contribution, and
      an allocation of Plan earnings, and charged with withdrawals and an
      allocation of Plan losses and administrative expenses.  Allocations
      are based on participant earnings or account balances, as defined.
      The benefit to which a participant is entitled is the benefit that
      can be provided from the participant's vested account.

      Vesting -- Participants are vested immediately in their contributions
      plus actual earnings thereon. For participants not 100% vested as a
      result of the Company merger, vesting in the Company's contributions
      is based on continuous service.  A participant vests 20% each year
      upon completing two years of service.  A participant is 100% vested
      after completing six years of service.

      Forfeitures -- Prior to the Plan being frozen, forfeited nonvested
      accounts were used to reduce Company contributions.  Subsequent to
      the Plan being frozen, forfeited nonvested accounts were used to pay
      administrative expenses and then allocated to participants.

 5
      Investments -- Participants may direct the investment of their
      contributions into the eighteen investment options offered by the
      Plan.

      Participant Loans -- Participants may borrow from their vested
      accounts with a minimum of $1,000 up to a maximum of $50,000 or 50%
      of their account balance, whichever is less.  The loans are secured
      by the balance in the participant's account.  Principal and interest
      are paid ratably through payroll deductions.  As of May 1, 2006, the
      Plan no longer offers new loans to participants.  The loans were
      written with original terms of two to five years.  The interest rates
      were based on prevailing market conditions and are fixed over the
      life of the note.  Interest rates on participant loans at December
      31, 2006 and 2005 ranged from 5.25% to 7.50%.

      Payment of Benefits -- Participants in the Plan or beneficiaries are
      eligible to receive a benefit upon their termination, normal
      retirement date, early retirement date, death, financial hardship, or
      disability, as defined, equal to the amount in their individual
      accounts.


  2.  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      Basis of Accounting -- The accompanying financial statements have
      been prepared in accordance with accounting principles generally
      accepted in the United States of America.

      Use of Estimates -- The preparation of financial statements in
      conformity with accounting principles generally accepted in the
      United States of America requires management to make estimates and
      assumptions that affect the reported amounts of assets, liabilities,
      and changes therein and disclosure of contingent assets and
      liabilities. Actual results could differ from those estimates.

      Risks and Uncertainties -- The Plan utilizes various investment
      instruments, including mutual funds and a common collective fund.
      Investment securities, in general, are exposed to various risks, such
      as interest rate, credit, and overall market volatility.  Due to the
      level of risk associated with certain investment securities, it is
      reasonably possible that changes in the values of investment
      securities will occur in the near term and that such changes could
      materially affect the amounts reported in the financial statements.

      Investment Valuation and Income Recognition -- The Plan's investments
      are stated at fair value except for the Marshall & Ilsley Stable
      Principal Fund (the "Fund"), which is stated at fair value and then
      adjusted to contract value.  The Fund invests in guaranteed
      investment contracts.  Fully benefit-responsive investment contracts
      are valued at fair value.  Under the terms of the investment
      contracts, the crediting interest rate is determined semi-annually
      based on the insurance company's applicable rate schedule.  There are
      no limitations on guarantees of the contracts.

      Quoted market prices are used to value investments held by the Plan
      as well as the underlying investments of the Master Trusts in which
      the Plan invests.  Shares of mutual funds are valued at quoted market
      prices, which represent the net asset value of shares held by the
      Plan at year end.  Participant loans are valued at the outstanding
      loan balances.

      Purchases and sales of securities are recorded on a trade-date basis.
      Interest income is recorded on the accrual basis. Dividends are
      recorded on the ex-dividend date.

      Management fees and operating expenses charged to the Plan for
      investments in the mutual funds are deducted from income earned on a
      daily basis and are not separately reflected.  Consequently,
      management fees and operating expenses are reflected as a reduction
      of investment return for such investments.


 6
      Administrative Expenses -- Significantly all administrative expenses
      of the Plan were paid by the Corporation for the year ended December
      31, 2006.

      Payment of Benefits -- Benefit payments to participants are recorded
      upon distribution.  There were no amounts allocated to participants
      who elected to withdraw from the Plan but were not yet paid as of
      December 31, 2006 and 2005.

      Adoption of New Accounting Guidance -- The financial statements
      reflect the retroactive adoption of Financial Accounting Standards
      Board Staff Position, FSP AAG INV-1 and SOP 94-4-1, Reporting of
      Fully Benefit-Responsive Contracts Held by Certain Investment
      Companies Subject to the AICPA Investment Company Guide and
      Defined-Contribution Health and Welfare and Pension Plans (the
      "FSP").  As required by the FSP, the statements of net assets
      available for benefits presents investment contracts at fair value as
      well as an additional line item showing an adjustment of fully
      benefit responsive contracts from fair value to contract value.  The
      statement of changes in net assets available for benefits is
      presented on a contract value basis and was not affected by the
      adoption of the FSP.


  3.  INVESTMENTS

      The Plan's investments that represented 5% or more of the Plan's net
      assets available for benefits as of December 31, 2006 and 2005 are as
      follows:


                                              2006            2005
                                        --------------- ---------------
                                                 

      M&I Master Trust --
        Common Stock Fund*              $      172,216  $          --
      M&I Stable Principal Fund*               240,679             --
      M&I Master Trust --
        Aggressive Stock Fund*                 241,075             --
      Vanguard Institutional Index Fund        423,755             --
      Goldman Sachs Small-Cap Value Fund       211,873             --
      Marshall Mid-Cap Value Fund*             252,672             --
      Nicholas Fund                            188,729             --
      Marshall International Stock Fund*       327,127             --
      Principal Global Investors Money Market*     --          264,674
      Principal Global Investors
        Bond and Mortgage*                         --          390,970
      Principal Global Investors
        Mid-Cap Value I*                           --          359,883
      Principal Global Investors
        Large-Cap Blend I*                         --          232,635
      Principal Global Investors
        Large Cap Stock Index*                     --          498,704
      Principal Global Investors
        Medium Company Blend*                      --          284,212
      Principal Global Investors
        Diversified International*                 --          315,796

      * Represents party-in-interest


      During the year ended December 31, 2006, the Plan's investments
      (including gains and losses on investments bought and sold, as well
      as held during the year) appreciated in value as follows:


                                                    
      Mutual funds                                      $      328,495
                                                         --------------

      Net appreciation in fair value of investments     $      328,495
                                                         ==============



 7
  4.  INTEREST IN MASTER TRUSTS

      As of December 31, 2006, certain of the Plan's investment assets are
      held in trust accounts at the Trustee and consist of undivided
      interests in investments of the Master Trusts which are established
      by the Corporation and administered by the Trustee.  Use of the
      Master Trust permits the commingling of trust assets with the assets
      of the Plan's assets with the assets of the M&I Retirement Plan and
      the NYCE 401(k) Plan for investment and administrative purposes.
      Although assets of all three plans are commingled in the Master
      Trusts, the Trustee maintains supporting records for the purpose of
      allocating the net gain or loss of the investment account to the
      participating plans.  The net investment income of the investment
      assets is allocated by the Trustee to each participating plan based
      on the relationship of the interest of each plan to the total of the
      interests of the participating plans.

      The Plan's investments and income in the Master Trusts at December
      31, 2006, are summarized as follows:

      M&I Master Trust -- Aggressive Stock Fund


                                                
      Investments -- whose fair
        value is determined based
        on quoted market prices --
        mutual funds                                $  116,363,654
                                                     --------------

      Net assets of the M&I Master Trust --
        Aggressive Stock Fund                       $  116,363,654
                                                     ==============

      Plan's interest in net assets
        of the M&I Master Trust --
        Aggressive Stock Fund                       $      241,075
                                                     ==============

      Plan's interest in M&I Master Trust --
        Aggressive Stock Fund as a
        percentage of the total                               0.21 %
                                                     ==============


      Dividend and interest income                  $      942,819

      Net appreciation in the fair
        value of investments --
        mutual funds                                    14,455,227
                                                     --------------
      Total M&I Master Trust -- Aggressive
        Stock Fund income                           $   15,398,046
                                                     ==============


      M&I Master Trust -- Growth Balanced Fund


                                                
      Investments -- whose fair
        value is determined based
        on quoted market prices --
        mutual funds                                $  127,634,361
                                                     --------------

      Net assets of the M&I Master Trust --
        Growth Balanced Fund                        $  127,634,361
                                                     ==============

      Plan's interest in net assets
        of the M&I Master Trust --
        Growth Balanced Fund                        $      142,881
                                                     ==============

      Plan's interest in M&I Master Trust --
        Growth Balanced Fund as a
        percentage of the total                               0.11 %
                                                     ==============


      Dividend and interest income                  $    2,724,630

      Net appreciation in the fair
        value of investments --
        mutual funds                                    10,296,520
                                                     --------------
      Total M&I Master Trust --
        Growth Balanced Fund income                 $   13,021,150
                                                     ==============


 8
      M&I Master Trust -- Aggressive Balanced Fund


                                                
      Investments -- whose fair
        value is determined based on
        quoted market prices --
        mutual funds                                $   18,624,234
                                                     --------------

      Net assets of the M&I Master Trust --
        Aggressive Balanced Fund                    $   18,624,234
                                                     ==============

      Plan's interest in net assets
        of the M&I Master Trust --
        Aggressive Balanced Fund                    $       33,025
                                                     ==============

      Plan's interest in M&I Master Trust --
        Aggressive Balanced Fund as
        a percentage of the total                             0.18 %
                                                     ==============


      Dividend and interest income                  $      243,808

      Net appreciation in the fair
        value of investments --
        mutual funds                                     1,610,942
                                                     --------------

      Total M&I Master Trust --
        Aggressive Balanced
        Fund income                                 $    1,854,750
                                                     ==============


      M&I Master Trust -- Moderate Balanced Fund


                                                
      Investments -- whose fair
        value is determined based
        on quoted market prices --
        mutual funds                                $    8,164,618
                                                     --------------

      Net assets of the M&I Master Trust --
        Moderate Balanced Fund                      $    8,164,618
                                                     ==============

      Plan's interest in net assets
        of the M&I Master Trust --
        Moderate Balanced Fund                      $      149,595
                                                     ==============

      Plan's interest in M&I Master Trust --
        Moderate Balanced Fund as
        a percentage of the total                             1.83 %
                                                     ==============

      Dividend and interest income                  $      179,817

      Net appreciation in the fair
        value of investments --
        mutual funds                                       370,800
                                                     --------------
      Total M&I Master Trust --
        Moderate Balanced
        Fund income                                 $      550,617
                                                     ==============


 9
      M&I Master Trust -- Diversified Stock Fund


                                                
      Investments -- whose fair
        value is determined based
        on quoted market prices --
        mutual funds                                $   23,233,811
                                                     --------------

       Net assets of the M&I Master Trust --
         Diversified Stock Fund                     $   23,233,811
                                                     ==============

       Plan's interest in net assets
         of the M&I Master Trust --
         Diversified Stock Fund                     $       94,238
                                                     ==============

       Plan's interest in M&I Master Trust --
         Diversified Stock Fund as
         a percentage of the total                            0.41 %
                                                     ==============


       Dividend and interest income                 $      227,035

       Net appreciation in the fair
         value of investments --
         mutual funds                                    2,384,163
                                                     --------------
       Total M&I Master Trust --
         Diversified Stock
         Fund income                                $    2,611,198
                                                     ==============


      M&I Master Trust -- Common Stock Fund


                                                
      Investments -- whose fair
        value is determined based
        on quoted market prices --
        common stock                                $  483,516,733
                                                     --------------

      Net assets of the M&I Master Trust --
        Common Stock Fund                           $  483,516,733
                                                     ==============

      Plan's interest in net assets
        of the M&I Master Trust --
        Common Stock Fund                           $      172,216
                                                     ==============

      Plan's interest in M&I Master Trust --
        Common Stock Fund as a
        percentage of the total                               0.04 %
                                                     ==============


      Dividend and interest income                  $   10,761,089

      Net appreciation in the fair
        value of investments -- mutual funds            48,675,405
                                                     --------------

      Total M&I Master Trust --
        Common Stock Fund income                    $   59,436,494
                                                     ==============


      At December 31, 2006, the M&I Master Trust -- Common Stock Fund held
      10,024,546 shares of common stock of the Corporation, the sponsoring
      employer, with a cost basis of $142,705,068.  During the year ended
      December 31, 2006, the M&I Master Trust -- Common Stock Fund recorded
      dividend income of $10,702,171.


  5.  FEDERAL INCOME TAX STATUS

      The Plan is a Non-Standardized Prototype Plan ("Prototype Plan")
      sponsored by the Trustee and adopted by the Corporation. The Plan has
      not requested its own determination letter from the Internal Revenue
      Service. However, the Corporation and Plan administrator believe that
      the Plan is currently designed and being operated in compliance with
      the applicable requirements of the Internal Revenue Code and the Plan
      continues to be tax-exempt.  Therefore, no provision for income taxes
      has been included in the Plan's financial statements.

 10
  6.  EXEMPT PARTY-IN-INTEREST TRANSACTIONS

      Certain Plan investments are shares of mutual funds, a common
      collective fund, and Master Trusts managed by the Trustee.  The
      Corporation is the trustee as defined by the Plan and, therefore,
      these transactions qualify as exempt party-in-interest transactions.
      Fees paid by the Plan for investment management services were
      included as a reduction of the return earned on each fund.


  7.  PLAN TERMINATION

      Although it has not expressed any intention to do so, the Company has
      the right under the Plan to discontinue its contributions at any time
      and to terminate the Plan subject to the provisions set forth in
      ERISA.  In the event that the Plan is terminated, all participants
      would be 100% vested in their accounts.


  8.  RECONCILIATION OF FINANCIAL STATEMENTS TO FORM 5500

      The reconciliation of net assets available for benefits and changes
      in net assets available for benefits per the financial statements to
      the Form 5500 as of and for the year ended December 31, 2006, is as
      follows:


                                                
      Statement of net assets available for benefits:
        Net assets available for benefits
          per the financial statements              $    3,181,404
        Adjustments from contract value to
          fair value for fully benefit-
          responsive investment contracts                   (2,992)
                                                     --------------
      Net assets available for benefits
        per the Form 5500 -- at fair value          $    3,178,412
                                                     ==============

      Statement of changes in net assets available for benefits:
        Decrease in net assets per
          the financial statements                  $     (116,095)
        Adjustment from contract value to
          fair value for fully benefit-
          responsive investment contracts                   (2,992)
                                                     --------------
      Net loss per Form 5500                        $     (119,087)
                                                     ==============



 10.  SUBSEQUENT EVENT

      In early April 2007, the Corporation announced its plan to separate
      Marshall & Ilsley Corporation and Metavante Corporation into two
      separate publicly traded companies.  This transaction, which is
      contingent upon satisfaction of various closing conditions, is
      expected to close in the fourth quarter of 2007.  The closing
      conditions include approval of Marshall & Ilsley Corporation
      shareholders, who will be asked to vote on the proposed transaction
      at a special meeting that will be held on a date to be announced,
      obtaining a favorable ruling from the Internal Revenue Service and
      other regulatory approvals.  The impact of this proposed transaction
      on the Plan is currently unknown.


                                * * * * * *

 11
                           SUPPLEMENTAL SCHEDULE

 12
MISSOURI STATE BANK & TRUST COMPANY RETIREMENT SAVINGS PLAN

FORM 5500, SCHEDULE H, PART IV, LINE 4i --
SCHEDULE OF ASSETS (HELD AT END OF YEAR)
AS OF DECEMBER 31, 2006

                         Description of Investment,
                          Including Maturity Date,
                        Rate of Interest, Collateral,    Current
        Issuer           and Par or Maturity Value        Value
---------------------- ------------------------------ -------------


                                               
M&I Master Trust --
  Growth Balanced Fund* Master Trust                  $    142,881
M&I Stable
  Principal Fund*       Common Collective Fund             240,679
M&I Master Trust -- Aggressive
  Balanced Fund*        Master Trust                        33,025
Vanguard Institutional
  Index Fund            Registered Investment Company      423,755
M&I Master Trust -- Moderate
  Balanced Fund*        Master Trust                       149,595
Goldman Sachs Small-Cap
  Value Fund            Registered Investment Company      211,873
Marshall Mid-Cap
  Value Fund*           Registered Investment Company      252,672
Nicholas Fund           Registered Investment Company        8,729
Marshall Intermediate
  Bond Fund*            Registered Investment Company       96,516
Managers Special
  Equity Fund           Registered Investment Company      107,434
Marshall Mid-Cap
  Growth Fund*          Registered Investment Company      137,159
Marshall International
  Stock Fund*           Registered Investment Company      327,127
Marshall Large Cap
  Value Fund*           Registered Investment Company      147,482
M&I Master Trust -- Diversified
  Stock Fund*           Master Trust                        94,238
M&I Master Trust -- Aggressive
  Stock Fund*           Master Trust                       241,075
MFS Massachusetts
  Growth Fund           Registered Investment Company       53,505
Marshall Large Cap
  Growth & Income Fund* Registered Investment Company      146,947
M&I Master Trust --
  Common Stock Fund*    Master Trust                       172,216
Various participants*   Participant Loans (at interest
                          rates of 5.25% - 7.50%)           11,735
                                                       ------------
                                                      $  3,178,643
                                                       ============
* Represents party-in-interest



                                 SIGNATURES
                                 ----------

Pursuant to the requirements of the Securities Exchange Act of 1934, the
trustees (or other persons who administer the employee benefit plan) have
duly caused this annual report to be signed by the undersigned thereunto
duly authorized.


                                     Missouri State Bank & Trust
                                       Company Retirement Savings Plan

                                     /s/ Dennis R. Salentine
                                     ____________________________

                                     Dennis R. Salentine
                                     Vice President,and
                                       Director of Corporate
                                       Benefits of the Marshall
                                       & Ilsley Corporation


Date: June 29, 2007