8-K

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 26, 2007

MARSHALL & ILSLEY CORPORATION

(Exact name of registrant as specified in its charter)

Wisconsin	1-15403	39-0968604
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

770 North Water Street             Milwaukee, Wisconsin	53202
(Address of principal executive offices)	(Zip Code)

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:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01.

Other Events.

On April 26, 2007, Marshall & Ilsley Corporation (the “Company”) purchased 3.25 million shares, or approximately 1.2 percent, of its outstanding common stock from Merrill Lynch International through an accelerated share repurchase program.  The shares were purchased at $48.03 per share for a total cost of approximately $156 million.

A copy of the press release issued by the Company announcing and describing the accelerated share repurchase is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01.

Financial Statements and Exhibits.

Exhibit No.	Description
99.1	Press Release dated April 26, 2007

2

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.

Dated:  May 2, 2007	MARSHALL & ILSLEY CORPORATION
	By:/s/ Randall J. Erickson
	Randall J. Erickson Senior Vice President, Chief Administrative Officer and General Counsel

3

EXHIBIT INDEX

Exhibit No.	Description
99.1	Press Release dated April 26, 2007

4

EX-99.1

Exhibit 99.1

News Release		Marshall & Ilsley Corporation
		770 North Water Street
		Milwaukee, WI 53202
		414 765-7700 Main
		414 298-2921 Fax
		mibank.com
For Release:	Immediately
Contact:	Greg Smith, senior vice president, chief financial officer 414 765-7727 Dave Urban, vice president, director of investor relations 414 765-7853

MARSHALL & ILSLEY CORPORATION ENTERS INTO

ACCELERATED SHARE BUYBACK

Milwaukee, Wis. – April 26, 2007 – Marshall & Ilsley Corporation (NYSE: MI) (M&I) today announced it has repurchased 3.25 million shares, or approximately 1.2 percent of its outstanding common stock.

The shares were purchased from Merrill Lynch International through an accelerated share repurchase program at $48.03 per share for a total cost of approximately $156 million.

The accelerated share repurchase program enabled M&I to purchase the shares immediately, while Merrill Lynch International will purchase shares in the open market over a period not expected to exceed 60 days. After this period, M&I may receive or be required to pay a price adjustment based on an adjusted weighted average price as defined in its agreement with Merrill Lynch International.

After the repurchase that was announced today, approximately 8.75 million shares remain available under prior repurchase authorizations by Marshall & Ilsley Corporation’s Board of Directors. After this repurchase, M&I has approximately 259 million common shares outstanding.

Marshall & Ilsley Corporation (NYSE: MI) is a diversified financial services corporation headquartered in Milwaukee, Wis., with $56.5 billion in assets. Founded in 1847, M&I Marshall & Ilsley Bank is the largest Wisconsin-based bank, with 193 offices throughout the state. In addition, M&I has 47 locations throughout Arizona; 30 offices along Florida’s west coast and central Florida; 17 offices in Kansas City and nearby communities; 17 offices in

metropolitan Minneapolis/St. Paul, and one in Duluth, Minn.; three offices in Tulsa, Okla.; and one office in Las Vegas, Nev. M&I’s Southwest Bank subsidiary has 16 offices in the greater St. Louis area. Metavante Corporation, a wholly owned subsidiary, provides a full array of technology products and services for the financial services industry. On April 3, 2007, Marshall & Ilsley Corporation announced its plans to split Metavante Corporation and Marshall & Ilsley Corporation into independent publicly traded companies. M&I also provides trust and investment management, equipment leasing, mortgage banking, asset-based lending, financial planning, investments, and insurance services from offices throughout the country and on the Internet (www.mibank.com or www.micorp.com). M&I’s customer-based approach, internal growth, and strategic acquisitions have made M&I a nationally recognized leader in the financial services industry.

This press release contains forward-looking statements concerning M&I’s future operations and financial results. Such statements are subject to important factors that could cause M&I’s actual results to differ materially from those anticipated by the forward-looking statements. These factors include (i) the factors identified in M&I’s Annual Report on Form 10-K for the year ended December 31, 2006 under the heading “Forward-Looking Statements” which factors are incorporated herein by reference, and (ii) such other factors as may be described from time to time in M&I’s SEC filings.

###