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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                         ------------------------------
                                  SCHEDULE TO/A

            TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
                               (Amendment No. 23)
                              TAUBMAN CENTERS, INC.
                       (Name of Subject Company (Issuer))
                        SIMON PROPERTY ACQUISITIONS, INC.
                           SIMON PROPERTY GROUP, INC.
                             WESTFIELD AMERICA, INC.
                      (Names of Filing Persons (Offerors))
                     COMMON STOCK, PAR VALUE $.01 PER SHARE
                         (Title of Class of Securities)
                                    876664103
                      (CUSIP Number of Class of Securities)
          James M. Barkley, Esq.                 Peter R. Schwartz, Esq.
        Simon Property Group, Inc.               Westfield America Inc.
           National City Center                 11601 Wilshire Boulevard
        115 West Washington Street                     12th Floor
              Suite 15 East                       Los Angeles, CA 90025
          Indianapolis, IN 46024                Telephone: (310) 445-2427
        Telephone: (317) 636-1600
                 (Name, Address and Telephone Numbers of Person
  Authorized to Receive Notices and Communications on Behalf of Filing Persons)
                         ------------------------------
                                   Copies to:
    Steven A. Seidman, Esq.                    Scott V. Simpson, Esq.
    Robert B. Stebbins, Esq.          Skadden, Arps, Slate, Meagher & Flom LLP
    Willkie Farr & Gallagher                      One Canada Square
       787 Seventh Avenue                           Canary Wharf
    New York, New York 10019                  London, E14 5DS, England
   Telephone: (212) 728-8000                Telephone: (44) 20 7519 7000

                         ------------------------------
                            CALCULATION OF FILING FEE

================================================================================ TRANSACTION VALUATION* AMOUNT OF FILING FEE** - -------------------------------------------------------------------------------- $ 1,221,120,520 $ 244,224.10 ================================================================================
* Estimated for purposes of calculating the amount of the filing fee only. Calculated by multiplying $20.00, the per share tender offer price, by 61,056,026 shares of Common Stock, consisting of (i) 52,270,965 outstanding shares of Common Stock, (ii) 2,269 shares of Common Stock issuable upon conversion of 31,767,066 outstanding shares of Series B Non-Participating Convertible Preferred Stock, (iii) 7,185,009 shares of Common Stock issuable upon conversion of outstanding partnership units of The Taubman Realty Group, Limited Partnership ("TRG") and (iv) 1,597,783 shares of Common Stock issuable upon conversion of outstanding options (each of which entitles the holder thereof to purchase one partnership unit of TRG which, in turn, is convertible into one share of Common Stock), based on Amendment No. 1 to the Registrant's Preliminary Proxy Statement on Schedule 14A filed on February 25, 2003, the Registrant's Schedule 14D-9 filed on December 11, 2002 and the Registrant's Annual Report on Form 10-K for the year ended December 31, 2002. ** The amount of the filing fee calculated in accordance with Regulation 240.0-11 of the Securities Exchange Act of 1934, as amended, equals 1/50th of one percent of the value of the transaction. /X/ Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing. Amount Previously Paid: $248,745.11 Filing Party: Simon Property Group, Inc.; Simon Property Form or Registration No.: Schedule TO (File No. 005-42862), Acquisitions, Inc.; Westfield America, Inc. Amendment No. 1 to the Schedule TO Date Filed: December 5, 2002, December 16, 2002 and and Amendment No. 5 to the Schedule TO January 15, 2003
/ / Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer. / / Check the appropriate boxes below to designate any transactions to which the statement relates. /X/ third-party tender offer subject to Rule 14d-1. / / issuer tender offer subject to Rule 13e-4. / / going-private transaction subject to Rule 13e-3. / / amendment to Schedule 13D under Rule 13d-2. Check the following box if the filing is a final amendment reporting the results of the tender offer: / / ================================================================================ SCHEDULE TO This Amendment No. 23 amends and supplements the Tender Offer Statement on Schedule TO originally filed with the Securities and Exchange Commission (the "Commission") on December 5, 2002, as amended and supplemented by Amendment No. 1 thereto filed with the Commission on December 16, 2002, by Amendment No. 2 thereto filed with the Commission on December 27, 2002, by Amendment No. 3 thereto filed with the Commission on December 30, 2002, by Amendment No. 4 thereto filed with the Commission on December 31, 2002, by Amendment No. 5 thereto filed with the Commission on January 15, 2003, by Amendment No. 6 thereto filed with the Commission on January 15, 2003, by Amendment No. 7 thereto filed with the Commission on January 16, 2003, by Amendment No. 8 thereto filed with the Commission on January 22, 2003, by Amendment No. 9 thereto filed with the Commission on January 23, 2003, by Amendment No. 10 thereto filed with the Commission on February 7, 2003, by Amendment No. 11 thereto filed with the Commission on February 11, 2003, by Amendment No. 12 thereto filed with the Commission on February 18, 2003, by Amendment No. 13 thereto filed with the Commission on February 21, 2003, by Amendment No. 14 thereto filed with the Commission on February 21, 2003, by Amendment No. 15 thereto filed with the Commission on February 27, 2003, by Amendment No. 16 thereto filed with the Commission on February 27, 2003, by Amendment No. 17 thereto filed with the Commission on February 28, 2003, by Amendment No. 18 thereto filed with the Commission on March 3, 2003, by Amendment No. 19 thereto filed with the Commission on March 6, 2003, by Amendment No. 20 thereto filed with the Commission on March 18, 2003, by Amendment No. 21 thereto filed with the Commission on March 21, 2003 and by Amendment No. 22 thereto filed with the Commission on March 28, 2003 (as amended and supplemented, the "Schedule TO") relating to the offer by Simon Property Acquisitions, Inc., a Delaware corporation (the "Purchaser") and wholly owned subsidiary of Simon Property Group, Inc., a Delaware corporation ("SPG Inc."), to purchase all of the outstanding shares of common stock, par value $.01 per share (the "Shares"), of Taubman Centers, Inc. (the "Company") at a purchase price of $20.00 per Share, net to the seller in cash, without interest thereon, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated December 5, 2002 (the "Offer to Purchase"), and the Supplement to the Offer to Purchase, dated January 15, 2003 (the "Supplement"), and in the related revised Letter of Transmittal (which, together with any supplements or amendments, collectively constitute the "Offer"). This Amendment No. 23 to the Schedule TO is being filed on behalf of the Purchaser, SPG Inc. and Westfield America, Inc. ("WEA"). Capitalized terms used and not defined herein shall have the meanings assigned to such terms in the Offer to Purchase, the Supplement and the Schedule TO, as applicable. The item numbers and responses thereto below are in accordance with the requirements of Schedule TO. Item 11. ADDITIONAL INFORMATION. On March 31, 2003, SPG Inc., the Purchaser and WEA announced that the Expiration Date of the Offer has been extended to 12:00 midnight, New York City time, on May 30, 2003. The full text of a press release, dated March 31, 2003, issued by SPG Inc. and WEA with respect to such announcement is filed herewith as Exhibit (a)(5)(RR). Item 12. EXHIBITS. (a)(5)(RR) Press release issued by Simon Property Group, Inc. and Westfield America, Inc., dated March 31, 2003. SIGNATURE After due inquiry and to the best of their knowledge and belief, the undersigned hereby certify as of March 31, 2003 that the information set forth in this statement is true, complete and correct. SIMON PROPERTY GROUP, INC. By: /s/ James M. Barkley ----------------------------- Name: James M. Barkley Title: Secretary and General Counsel SIMON PROPERTY ACQUISITIONS, INC. By: /s/ James M. Barkley ----------------------------- Name: James M. Barkley Title: Secretary and Treasurer After due inquiry and to the best of its knowledge and belief, the undersigned hereby certifies as of March 31, 2003 that the information set forth in this statement is true, complete and correct. WESTFIELD AMERICA, INC. By: /s/ Peter R. Schwartz ---------------------------------- Name: Peter R. Schwartz Title: Senior Executive Vice President EXHIBIT INDEX EXHIBIT NO. DESCRIPTION - --------------- ------------------------------------------------------------- (a)(5)(RR) Press release issued by Simon Property Group, Inc. and Westfield America, Inc., dated March 31, 2003.


                                                    Exhibit 99(a)(5)(RR)

[SIMON PROPERTY GROUP LOGO]                                  [WESTFIELD LOGO]


SIMON INVESTOR CONTACT:      MEDIA CONTACT:          WESTFIELD INVESTOR CONTACT:
Shelly Doran                 George Sard/Paul        Katy Dickey
Simon Property Group, Inc.   Caminiti/Hugh Burns     Westfield America
317/685-7330                 Citigate Sard Verbinnen 310/445-2407
                             212/687-8080


            SIMON PROPERTY GROUP AND WESTFIELD AMERICA EXTEND TENDER
                    OFFER FOR TCO COMMON SHARES UNTIL MAY 30

         NEW YORK, MARCH 31, 2003 -- Simon Property Group, Inc. (NYSE: SPG) and
Westfield America, Inc., the U.S. subsidiary of Westfield America Trust (ASX:
WFA), today announced that they have extended their $20.00 per share all-cash
offer for Taubman Centers, Inc. (NYSE: TCO) shares until midnight, New York City
time, on Friday, May 30, 2003, unless further extended.

                                      * * *

         The $20.00 per share all-cash offer for TCO shares will expire on
midnight, New York City time, on May 30, 2003, unless further extended. As of
midnight, New York City time, on March 28, 2003, TCO shareholders had tendered
and not withdrawn approximately 40,302,385 shares. The complete terms and
conditions of the offer are set forth in the Offer to Purchase, as amended, and
the related Letter of Transmittal, copies of which are on file with the SEC and
available by contacting the information agent, MacKenzie Partners, Inc. at (800)
322-2885. Merrill Lynch & Co. is acting as financial advisor to SPG and
Westfield America, Inc. and is the Dealer Manager for the Offer. Willkie Farr &
Gallagher is acting as legal advisor to SPG and Skadden, Arps, Slate, Meagher &
Flom LLP is acting as legal advisor to Westfield America, Inc. Simpson Thacher &
Bartlett is acting as legal advisor to Merrill Lynch & Co.

ABOUT SIMON PROPERTY GROUP

Headquartered in Indianapolis, Indiana, Simon Property Group, Inc. is a real
estate investment trust engaged in the ownership and management of
income-producing properties, primarily regional malls and community shopping
centers. Through its subsidiary partnerships, it currently owns or has an
interest in 242 properties containing an aggregate of 183 million square feet of
gross leasable area in 36 states, as well as nine assets in Europe and Canada
and ownership interests in other real estate assets. Additional Simon Property
Group, Inc. information is available at
http://about.simon.com/corpinfo/index.html.

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ABOUT WESTFIELD AMERICA, INC.

Westfield America, Inc. is the United States subsidiary of Westfield America
Trust (ASX: WFA), the second-largest property trust listed on the Australian
Stock Exchange. WFA owns a majority interest in the Westfield America portfolio
of 63 centers, branded as Westfield Shoppingtowns. Westfield Shoppingtowns are
home to more than 8,400 specialty stores and encompass 64 million square feet in
the states of California, Colorado, Connecticut, Florida, Illinois, Indiana,
Maryland, Missouri, Nebraska, New Jersey, New York, North Carolina, Ohio and
Washington.

                                      # # #

IMPORTANT INFORMATION

This news release is for informational purposes only and is not an offer to buy
or the solicitation of an offer to sell any TCO shares, and is not a
solicitation of a proxy. Simon Property Group, Inc. and Simon Property
Acquisitions, Inc., a wholly owned subsidiary of Simon Property Group, Inc.
filed a tender offer statement on Schedule TO with the Securities and Exchange
Commission on December 5, 2002 (as amended), with respect to the offer to
purchase all outstanding shares of TCO common stock. Investors and security
holders are urged to read this tender offer statement as amended because it
contains important information. Investors and security holders may obtain a free
copy of the tender offer statement and other documents filed by SPG and
Westfield America, Inc. with the Commission at the Commission's web site at
http://www.sec.gov. The tender offer statement and any related materials may
also be obtained for free by directing such requests to MacKenzie Partners, Inc.
at (800) 322-2885.

SPG and Westfield America, Inc. and certain other persons may be deemed
participants in the solicitation of proxies from the shareholders of TCO in
connection with TCO's 2003 Annual Meeting of Shareholders. Information
concerning such participants is available in the tender offer statement and
other documents filed by SPG and Westfield with the Commission as described
above, and further information will be available in SPG/Westfield's Preliminary
Proxy Statement and Definitive Proxy Statement to be filed with the Commission
in connection with the solicitation of proxies in due course.

Shareholders of TCO are advised to read SPG/Westfield's Definitive Proxy
Statement in connection with SPG/Westfield's solicitation of proxies from TCO
shareholders when it becomes available, because it will contain important
information. Shareholders of TCO and other interested parties may obtain, free
of charge, copies of the Preliminary Proxy Statement and the Definitive Proxy
Statement (when available), and any other documents filed by SPG/Westfield with
the Commission in connection with the proxy solicitation at the Commission's
website as described above. The Preliminary Proxy Statement and the Definitive
Proxy Statement (when available) and these other documents may also be obtained
free of charge by contacting MacKenzie Partners, Inc., the firm assisting
SPG/Westfield in the solicitation of proxies, toll-free at the number listed
above.

FORWARD-LOOKING STATEMENTS

This release contains some forward-looking statements as defined by the federal
securities laws which are based on our current expectations and assumptions,
which are subject to a number of risks and uncertainties that could cause actual
results to differ materially from those anticipated, projected or implied. We
undertake no obligation to publicly update any forward-looking statements,
whether as a result of new information, future events or otherwise.


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