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     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JULY 24, 2003
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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------

                                  FORM 20-F/A
                               (AMENDMENT NO. 1)

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            / /     REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF
                    THE SECURITIES EXCHANGE ACT OF 1934
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                                       OR

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            /X/     ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                    SECURITIES EXCHANGE ACT OF 1934
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                  For the fiscal year ended December 31, 2002

                                       OR

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            / /     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                    SECURITIES EXCHANGE ACT OF 1934
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                       Commission file number: 001-16429
                            ------------------------
                                    ABB LTD
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

                                  SWITZERLAND

                (JURISDICTION OF INCORPORATION OR ORGANIZATION)

                              AFFOLTERNSTRASSE 44
                                 CH-8050 ZURICH
                                  SWITZERLAND
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)

Securities registered or to be registered pursuant to Section 12(b) of the Act:

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                                                                        NAME OF EACH EXCHANGE
                    TITLE OF EACH CLASS                                  ON WHICH REGISTERED
----------------------------------------------------------- ---------------------------------------------
                AMERICAN DEPOSITARY SHARES,                            NEW YORK STOCK EXCHANGE
          EACH REPRESENTING ONE REGISTERED SHARE

           REGISTERED SHARES, PAR VALUE CHF 2.50                      NEW YORK STOCK EXCHANGE*
</Table>

------------------------------

*   Listed on the New York Stock Exchange not for trading or quotation purposes,
    but only in connection with the registration of American Depositary Shares
    pursuant to the requirements of the Securities and Exchange Commission.

Securities registered or to be registered pursuant to Section 12(g) of the Act:
                                     None.

 Securities for which there is a reporting obligation pursuant to Section 15(d)
                               of the Act: None.

  Indicate the number of outstanding shares of each of the issuer's classes of
  capital or common stock as of the close of the period covered by the annual:
                        1,200,009,432 Registered Shares
                            ------------------------

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                               Yes  /X/    No  / /

Indicate by check mark which financial statement item the registrant has elected
to follow.

                          Item 17  / /    Item 18  /X/

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                                EXPLANATORY NOTE

    This Form 20-F/A is being filed by ABB Ltd ("ABB") as Amendment No. 1 to its
Annual Report on Form 20-F filed on June 30, 2003 (the "Form 20-F") for the
purpose of revising Exhibit 99.2 under Item 19 by:

    - deleting in their entirety the consolidated financial statements of Jorf
      Lasfar Energy Company S.C.A. ("JLEC"), an entity in which ABB owns a 50%
      interest, for the financial year ended December 31, 2002 included as
      Exhibit 99.2 to the Form 20-F; and

    - including as Exhibit 99.2 the restated consolidated financial statements
      of JLEC for the financial year ended December 31, 2002.

    In the JLEC financial statements that were included as Exhibit 99.2 to ABB's
Form 20-F filed on June 30, 2003, JLEC had reflected its investment in certain
direct financing leases on a gross basis. ABB has been advised that JLEC has
restated its 2002 financial statements to properly present this lease-related
information on a net basis. The impact of the restatement, as of December 31,
2002, was to increase JLEC's total current assets by approximately $52 million,
reduce its total non-current assets by approximately $1,232 million, increase
its total current liabilities by approximately $3 million and reduce its total
non-current liabilities by approximately $1,183 million. The net assets of JLEC
and its reported earnings are unaffected by the restatement.

    Pursuant to the requirements of Rule 4-08(g) under Regulation S-X, ABB
provided summary financial information relating to JLEC in Note 13 to its 2002
consolidated financial statements contained in Item 18 of its Form 20-F. The
restatement of the JLEC financial statements has not affected the carrying value
of ABB's investment in JLEC, or the amount of earnings of JLEC recognized in
ABB's consolidated financial statements. Consequently, ABB believes the
revisions to the JLEC financial statements are immaterial to ABB.

    As ABB is not required to file the JLEC financial statements pursuant to
Rule 3-09 under Regulation S-X and has elected to provide these financial
statements solely for purposes of additional disclosure, ABB is filing the
restated financial statements of JLEC as Exhibit 99.2 with this Form 20-F/A.

    This Form 20-F/A consists of a cover page, this explanatory note, Item 19
(as amended), the signature page, the required certifications of the chief
executive officer and the chief financial officer of ABB and the revised
Exhibit 99.2.

    Other than as expressly set forth above, this Form 20-F/A does not, and does
not purport to, amend, update or restate the information in any other Item of
the Form 20-F filed on June 30, 2003 or reflect any events that have occurred
after the Form 20-F was filed on June 30, 2003.

ITEM 19. EXHIBITS

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1.1                     Articles of Incorporation of ABB Ltd as amended to date.*

2.1                     Form of Amended and Restated Deposit Agreement, by and among
                        ABB Ltd, Citibank, N.A., as Depositary, and the holders and
                        beneficial owners from time to time of the American
                        Depositary Shares issued thereunder (including as an exhibit
                        the form of American Depositary Receipt). Incorporated by
                        reference to Exhibit (a)(i) to Post-Effective Amendment
                        No. 1 on Form F-6 (File No. 333-13346) filed by ABB Ltd on
                        May 7, 2001.

2.2                     Form of American Depositary Receipt (included in
                        Exhibit 2.1).
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                                       2
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2.3                     EMTN Amended and Restated Fiscal Agency Agreement, dated
                        May 30, 2001, between ABB International Finance Limited, ABB
                        Finance Inc., ABB Capital B.V., Banque Generale du
                        Luxembourg S.A., The Chase Manhattan Bank and Banque
                        Generale du Luxembourg (Suisse) S.A. Incorporated by
                        reference to Exhibit 2.3 to the Annual Report on Form 20-F
                        filed by ABB Ltd on June 27, 2002.

2.4                     EMTN Deed of Covenant, dated March 10, 1993 by ABB
                        International Finance N.V. Incorporated by reference to
                        Exhibit 2.4 to the Annual Report on Form 20-F filed by
                        ABB Ltd on June 27, 2002.

2.5                     EMTN Deed of Covenant, dated March 10, 1993 by ABB
                        Finance Inc. Incorporated by reference to Exhibit 2.5 to the
                        Annual Report on Form 20-F filed by ABB Ltd on June 27,
                        2002.

2.6                     EMTN Deed of Covenant, dated March 10, 1993 by ABB Capital
                        B.V. Incorporated by reference to Exhibit 2.6 to the Annual
                        Report on Form 20-F filed by ABB Ltd on June 27, 2002.

                        The total amount of long-term debt securities of ABB Ltd
                        authorized under any other instrument does not exceed 10% of
                        the total assets of the ABB Group on a consolidated basis.
                        ABB Ltd hereby agrees to furnish to the Commission, upon its
                        request, a copy of any instrument defining the rights of
                        holders of long-term debt of ABB Ltd or of its subsidiaries
                        for which consolidated or unconsolidated financial
                        statements are required to be filed.

4.1                     Share Purchase and Settlement Agreement dated as of
                        March 31, 2000 among ABB Ltd, ALSTOM and ABB ALSTOM POWER
                        N.V., as amended. Incorporated by reference to Exhibit 4.1
                        to the Annual Report on Form 20-F filed by ABB Ltd on
                        June 27, 2002.

4.2                     Purchase Agreement, dated as of December 21, 1999, between
                        ABB Handels-Und Verwaltungs AG, as Seller, and British
                        Nuclear Fuels plc, as Purchaser, as amended. Incorporated by
                        reference to Exhibit 4.2 to the Annual Report on Form 20-F
                        filed by ABB Ltd on June 27, 2002.

4.3                     $1,500,000 Multicurrency Revolving Facilities Agreement
                        dated 17 December 2002 for ABB Ltd and Certain Subsidiaries
                        of ABB Ltd, as Borrowers and Guarantors, arranged by
                        Barclays Capital, Bayerische Hypo-und Vereinsbank AG, Credit
                        Suisse First Boston and Salomon Brothers International
                        Limited, with Credit Suisse First Boston acting as Facility
                        Agent and Trustee.*

4.4                     Amendment Agreement, dated 23 June 2003, relating to a
                        Facility Agreement dated 17 December 2002, between ABB Ltd
                        as Borrower and Obligor Agent and Credit Suisse First Boston
                        as Facility Agent and Trustee.*

4.5                     Sale and Purchase Agreement, dated 4 September 2002, between
                        ABB Financial Services B.V., General Electric Capital
                        Corporation and ABB Ltd.*

4.6                     Amendment Agreement, dated 29 November 2002, between ABB
                        Financial Services B.V., General Electric Capital
                        Corporation and ABB Ltd.*

4.7                     Employment Agreement of Jurgen Dormann, dated December 5,
                        2002.*

4.8                     Employment Agreement of Peter Voser, dated November 21,
                        2001.*

4.9                     Employment Agreement of Dinesh Paliwal, dated February 21,
                        2003.*

4.10                    Employment Agreement of Peter Smits, dated November 1,
                        2001.*

4.11                    Employment Agreement of Gary Steel, dated August 27, 2002.*
</Table>

                                       3
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 8.1                    Subsidiaries of ABB Ltd as of December 31, 2002.*

10.1                    Certification by the chief executive officer of ABB Ltd
                        pursuant to 18 U.S.C. Section 1350, as adopted pursuant to
                        Section 906 of the Sarbanes-Oxley Act of 2002.**

10.2                    Certification by the chief financial officer of ABB Ltd
                        pursuant to 18 U.S.C. Section 1350, as adopted pursuant to
                        Section 906 of the Sarbanes-Oxley Act of 2002.**

99.1                    Financial statements of Swedish Export Credit Corporation.*

99.2                    Financial statements of Jorf Lasfar Energy Company S.C.A.
</Table>

------------------------

*   Filed with ABB's Annual Report on Form 20-F on June 30, 2003.

**  This document is being furnished in accordance with SEC Release Nos. 33-8212
    and 34-74551.

                                       4
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                                   SIGNATURES

    The registrant hereby certifies that it meets all of the requirements for
filing on Form 20-F and that it has duly caused and authorized the undersigned
to sign this amendment to the annual report on Form 20-F on its behalf.

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                                                       ABB LTD

                                                       By:  /s/ JURGEN DORMANN
                                                            -----------------------------------------
                                                            Name: Jurgen Dormann
                                                            Title:  President, Chairman
                                                                  and Chief Executive Officer

                                                       By:  /s/ PETER VOSER
                                                            -----------------------------------------
                                                            Name: Peter Voser
                                                            Title:  Executive Vice President
                                                                  and Chief Financial Officer
</Table>

Date: July 24, 2003
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                                 CERTIFICATION

I, Jurgen Dormann, certify that:

1.  I have reviewed this annual report on Form 20-F of ABB Ltd; and

2.  Based on my knowledge, this annual report does not contain any untrue
    statement of a material fact or omit to state a material fact necessary to
    make the statements made, in light of the circumstances under which such
    statements were made, not misleading with respect to the period covered by
    this annual report.

Date: July 24, 2003

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                                               /s/ JURGEN DORMANN
                                               --------------------------------------------
                                               Jurgen Dormann
                                               Chief Executive Officer
</Table>

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                                 CERTIFICATION

I, Peter Voser, certify that:

1.  I have reviewed this annual report on Form 20-F of ABB Ltd; and

2.  Based on my knowledge, this annual report does not contain any untrue
    statement of a material fact or omit to state a material fact necessary to
    make the statements made, in light of the circumstances under which such
    statements were made, not misleading with respect to the period covered by
    this annual report.

Date: July 24, 2003

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                                               /s/ PETER VOSER
                                               --------------------------------------------
                                               Peter Voser
                                               Chief Financial Officer
</Table>