FILED PURSUANT TO RULE 424(b)(3)
REGISTRATION NO. 333-110451
333-110451-01
PROSPECTUS SUPPLEMENT NO. 5
$125,000,000
GATX CORPORATION
5% SENIOR CONVERTIBLE NOTES DUE 2023
FULLY AND UNCONDITIONALLY GUARANTEED BY
GATX FINANCIAL CORPORATION
AND SHARES OF COMMON STOCK
ISSUABLE UPON CONVERSION OF THE NOTES
This prospectus supplement supplements the prospectus dated January 20,
2004 of GATX Corporation and GATX Financial Corporation, as supplemented by
prospectus supplement No. 1 dated January 30, 2004, prospectus supplement No. 2
dated March 15, 2004, prospectus supplement no. 3 dated April 16, 2004 and
prospectus supplement no. 4 dated June 2, 2004, relating to the sale by certain
holders of our 5% Senior Convertible Notes due 2023 and the shares of our common
stock issuable upon conversion of the notes. You should read this prospectus
supplement in conjunction with the prospectus. This prospectus supplement is
qualified by reference to the prospectus except to the extent that the
information in this prospectus supplement supersedes the information contained
in the prospectus. Capitalized terms used in this prospectus supplement and not
otherwise defined herein have the meanings specified in the prospectus.
The following line items are hereby added to the table of Selling
Holders contained in the prospectus:
<Table>
<Caption>
PRINCIPAL AMOUNT OF
NOTES BENEFICIALLY NUMBER OF SHARES
OWNED THAT OF COMMON STOCK
NAME OF SELLING HOLDER MAY BE SOLD THAT MAY BE SOLD
- ---------------------- -------------------- ----------------
Standard Global Equity Partners SA, L.P......................... $ 149,000 6,289
Scorpion Offshore Investment Fund, Ltd.......................... 91,000 3,841
Relay 3 Asset Holding Co. Limited............................... 16,000 675
SP Holdings Ltd................................................. 49,000 2,068
Standard Pacific Capital Offshore Fund, Ltd..................... 1,212,000 51,157
Standard Global Equity Partners, L.P............................ 389,000 16,419
Barclays Global Investors Equity Hedge Fund II.................. 15,000 633
Standard Pacific MAC 16 Ltd..................................... 64,000 2,701
Standard Global Equity Partners II, L.P......................... 15,000 633
</Table>
In addition, the following line item in the table of Selling Holders
contained in the prospectus is hereby deleted therefrom:
<Table>
<Caption>
PRINCIPAL AMOUNT OF
NOTES BENEFICIALLY NUMBER OF SHARES
OWNED THAT OF COMMON STOCK
NAME OF SELLING HOLDER MAY BE SOLD THAT MAY BE SOLD
- ---------------------- ------------------- ----------------
S.A.C. Capital Associates, LLC................................. $ 1,000,000 42,209
</Table>
INVESTING IN THE NOTES AND OUR COMMON STOCK INVOLVES RISKS. SEE "RISK
FACTORS" BEGINNING ON PAGE 5 OF THE PROSPECTUS.
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NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE
ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.
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The date of this prospectus supplement is October 6, 2004