NOTICE OF GUARANTEED DELIVERY
 
                                 FOR TENDER OF
                           7.65% CAPITAL SECURITIES
               (LIQUIDATION AMOUNT $1,000 PER CAPITAL SECURITY)
                                      OF
                              M&I CAPITAL TRUST A
                    FULLY AND UNCONDITIONALLY GUARANTEED BY
 
                         MARSHALL & ILSLEY CORPORATION
 
  As set forth in the Exchange Offer, this Notice of Guaranteed Delivery, or
one substantially equivalent to this form, must be used to accept the Exchange
Offer (as defined below) if (i) certificates for the Trust's (as defined
below) 7.65% Capital Securities due December 1, 2026 (the "Old Capital
Securities") are not immediately available, (ii) Old Capital Securities, the
Letter of Transmittal and all other required documents cannot be delivered to
The Chase Manhattan Bank (the "Exchange Agent") on or prior to the Expiration
Date (as defined in the Prospectus referred to below) or (iii) the procedures
for delivery by book-entry transfer cannot be completed on a timely basis.
This Notice of Guaranteed Delivery may be delivered by hand, overnight courier
or mail, or transmitted by facsimile transmission, to the Exchange Agent. See
"The Exchange Offer--Procedures for Tendering Old Capital Securities" in the
Prospectus.
 
                 The Exchange Agent for the Exchange Offer is:
 
                           THE CHASE MANHATTAN BANK
 
By Mail or Hand Delivery:        By Facsimile         To Confirm by Telephone:
                                Transmission:
 
 The Chase Manhattan Bank       (212) 638-7375         Carlos Esteves: (212)
                                      or                      638-0828
 55 Water Street, Second        (212) 344-9367
        Floor     
 Room 234--North Building
 New York, New York 10041
   Attn: Carlos Esteves
 
  DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER THAN AS
SET FORTH ABOVE OR TRANSMISSION OF THIS NOTICE OF GUARANTEED DELIVERY VIA
FACSIMILE TO A NUMBER OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE A
VALID DELIVERY.
 
  THIS NOTICE OF GUARANTEED DELIVERY IS NOT TO BE USED TO GUARANTEE
SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE
GUARANTEED BY AN "ELIGIBLE INSTITUTION" UNDER THE INSTRUCTIONS THERETO, SUCH
SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE
SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.
 
LADIES AND GENTLEMEN:
 
  The undersigned hereby tenders to M&I Capital Trust A, a Delaware business
trust (the "Trust"), upon the terms and subject to the conditions set forth in
the Prospectus dated March 7, 1997 (as the same may be amended or supplemented
from time to time, the "Prospectus"), and the related Letter of Transmittal
(which together constitute the "Exchange Offer"), receipt of which is hereby
acknowledged, the aggregate liquidation amount of Old Capital Securities set
forth below pursuant to the guaranteed delivery procedures set forth in the
Prospectus under the caption "The Exchange Offer--Procedures for Tendering Old
Capital Securities."

 
Certificate No(s). (if available):        Name of Registered Holder(s):
 
 
- -------------------------------------     -------------------------------------
 
 
- -------------------------------------     -------------------------------------
Aggregate Liquidation Amount Tendered:    Address:
 
 
- -------------------------------------     -------------------------------------
 
 
Area Code and Telephone Number(s):        -------------------------------------
 
 
- -------------------------------------     -------------------------------------
 
If Old Capital Securities will be tendered by book-entry transfer, provide the
following information:
 
Signature(s): _________________________________________________________________
 
DTC Account Number: ___________________________________________________________
 
Date: _________________________________________________________________________
 
                                   GUARANTEE
                   (NOT TO BE USED FOR SIGNATURE GUARANTEE)
   
  The undersigned, a firm or other entity identified in Rule 17Ad-15 under the
Securities Exchange Act of 1934, as amended, as an "eligible guarantor
institution," including (as such terms are defined therein): (i) a bank; (ii)
a broker, dealer, municipal securities broker, municipal securities dealer,
government securities broker or government securities dealer; (iii) a credit
union; (iv) a national securities exchange, registered securities association
or clearing agency; or (v) a savings association that is a participant in a
Securities Transfer Association recognized program (each of the foregoing
being referred to as an "Eligible Institution"), hereby guarantees to deliver
to the Exchange Agent, at one of its addresses set forth above, either the Old
Capital Securities tendered hereby in proper form for transfer, or
confirmation of the book-entry transfer of such Old Capital Securities to the
Exchange Agent's account at The Depository Trust Company ("DTC"), pursuant to
the procedures for book-entry transfer set forth in the Prospectus, in either
case together with one or more properly completed and duly executed Letter(s)
of Transmittal (or facsimile thereof or Agent's Message in lieu thereof) and
any other required documents within three business days after the date of
execution of this Notice of Guaranteed Delivery. The undersigned acknowledges
that it must deliver the Letters of Transmittal (or a facsimile thereof or
Agent's Message in lieu thereof) and the Old Capital Securities (or a book-
entry confirmation) tendered hereby to the Exchange Agent within the time
period set forth above and that failure to do so could result in a financial
loss to the undersigned. 
 
 
Name of Firm:
           --------------------------
                                          -------------------------------------
 
Address:                                          Authorized Signature
    ------------------------------
 
 
                                          Name:
- -------------------------------------          --------------------------------
 
 
                                          Title:
Telephone Number:                             ---------------------------------
                ---------------------
 
                                          Dated:
                                               --------------------------------
 
NOTE: DO NOT SEND OLD CAPITAL SECURITIES WITH THIS NOTICE OF GUARANTEED
DELIVERY. ACTUAL SURRENDER OF OLD CAPITAL SECURITIES MUST BE MADE PURSUANT TO,
AND BE ACCOMPANIED BY, A PROPERLY COMPLETED AND DULY EXECUTED LETTER OF
TRANSMITTAL AND ANY OTHER REQUIRED DOCUMENTS.
 
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