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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. 20)

                              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**
--------------------------------------- ----------------------------------------
           $1,243,725,540                             $248,745.11
======================================= ========================================
*     Estimated for purposes of calculating the amount of the filing fee only.
      Calculated by multiplying $20.00, the per share tender offer price, by
      62,186,277 shares of Common Stock, consisting of (i) 52,207,756
      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) 7,097,979 shares of
      Common Stock issuable upon conversion of outstanding partnership units of
      The Taubman Realty Group, Limited Partnership ("TRG") and (iv) 2,878,273
      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 the Registrant's Preliminary Proxy Statement on Schedule
      14A filed on December 20, 2002, the Registrant's Schedule 14D-9 filed on
      December 11, 2002 and the Registrant's Quarterly Report on Form 10-Q for
      the period ended September 30, 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
                                                                                        Acquisitions, Inc.; Westfield America, Inc.
Form or Registration No.:   Schedule TO (File No. 005-42862), Amendment
                            No. 1 to the Schedule TO and Amendment No. 5  Date Filed:   December 5, 2002, December 16, 2002 and
                            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. 20 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 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, Amendment No. 14 thereto
filed with the Commission on February 21, 2003, Amendment No. 15 thereto filed
with the Commission on February 27, 2003, Amendment No. 16 thereto filed with
the Commission on February 27, 2003, Amendment No. 17 thereto filed with the
Commission on February 28, 2003, Amendment No. 18 filed with the Commission on
March 3, 2003 and Amendment No. 19 filed with the Commission on March 6, 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. 20 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  6.    PURPOSES OF THE TRANSACTION AND PLANS OR PROPOSALS.

            On March 18, 2003, SPG Inc. and WEA issued a press release and open
            letter to the Company's shareholders announcing their intention to
            propose four nominees for election to the Company's Board of
            Directors at the Company's upcoming annual meeting of shareholders.
            The press release is filed herewith as Exhibit (a)(5)(NN).




Item 12.    EXHIBITS.

(a)(5)(NN)  Press Release issued by Simon Property Group, Inc. and Westfield
            America, Inc., dated March 18, 2003.





                                    SIGNATURE

            After due inquiry and to the best of their knowledge and belief, the
undersigned hereby certify as of March 18, 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 18, 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)(NN)        Press Release issued by Simon Property Group, Inc. and
                  Westfield America, Inc., dated March 18, 2003.