UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  April 29, 2011

MARSHALL & ILSLEY CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code:  (414) 765-7801

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Item 2.02.

Results of Operations and Financial Condition.

On April 29, 2011, Marshall & Ilsley Corporation (“M&I”) issued a press release announcing its results of operations for the first quarter ended March 31, 2011.  A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

In addition, a copy of the supplemental financial data referenced in the earnings release is attached hereto as Exhibit 99.2.

Item 9.01.

Financial Statements and Exhibits.

Additional information for shareholders

In connection with M&I’s pending merger with Bank of Montreal (BMO), BMO has filed with the SEC a Registration Statement on Form F-4, which includes a Proxy Statement of M&I and a Prospectus of BMO, as well as other relevant documents concerning the proposed transaction.  M&I has filed with the SEC and has furnished to its shareholders the definitive Proxy Statement/Prospectus, commencing on or about April 14, 2011.  Shareholders are urged to read the Registration Statement and the Proxy Statement/Prospectus regarding the merger and any other relevant documents filed with the SEC, as well as any amendments or supplements to those documents as they become available, because they will contain important information.

A free copy of the Proxy Statement/Prospectus, as well as other filings containing information about BMO and M&I, may be obtained at the SEC’s Internet site (http://www.sec.gov).  You may also obtain these documents, free of charge, from BMO at www.BMO.com under the tab “About BMO - Investor Relations” and then under the heading “Frequently Accessed Documents,” from M&I by accessing M&I’s website at www.MICorp.com under the tab “Investor Relations” and then under the heading “SEC Filings,” or from M&I at (414) 765-7814.

BMO and M&I and certain of their directors and executive officers may be deemed to be participants in the solicitation of proxies from the shareholders of M&I in connection with the merger.  Information about the directors and executive officers of BMO is set forth in the proxy statement for BMO’s 2011 annual meeting of shareholders, as filed with the SEC on Form 6-K on February 25, 2011.  Information about the directors and executive officers of M&I is set forth in the proxy statement for M&I’s 2010 annual meeting of shareholders, as filed with the SEC on a Schedule 14A on March 12, 2010.  Additional information regarding the interests of those participants and other persons who may be deemed participants in the transaction may be obtained by reading the Proxy Statement/Prospectus regarding the merger when it becomes available.  Free copies of this document may be obtained as described in the preceding paragraph.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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