As filed with the Securities and Exchange Commission on June 30, 2006



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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549



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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



|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 November 30, 2005

OR



| ̈ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
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For the transition period from              to

OR



| ̈ | SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | -------------------------------------------------------------------------------------------

Date of event requiring this shell company report

Commission File Number 00-21742



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ACERGY S.A.

(Exact name of Registrant as specified in its charter)



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LUXEMBOURG

(Jurisdiction of incorporation or organization)

c/o Acergy M.S. Limited

Dolphin House, Windmill Road, Sunbury-on-Thames

Middlesex TW16 7HT England

(Address
of principal executive offices)

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

None

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

Common Shares, $2.00 par value

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 report:



|                               |  |             |  |  |  | 
|------------------------------ |  | ----------- |  |  |  | 
|Common Shares, $2.00 par value |  | 191,883,471 |  |  |  | 



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Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Exchange Act.    Yes  x    No ̈

If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or
15(d) of the Securities Exchange Act of 1934.    Yes ̈No  x

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 whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of
accelerated filer or large accelerated filer in Rule 12b-2 of the Exchange Act (Circle one):



|                             |  |                    |  |                       
|---------------------------- |  | ------------------ |  | ----------------------
|Large accelerated filer    x |  | Accelerated Filer ̈ |  | Non-accelerated filer ̈

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

Item 17 ̈Item 18    x

If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes ̈No  x



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EXPLANATORY NOTE

This Form 20-F/A is being filed by Acergy S.A. (Acergy) as Amendment No. 1 to its Annual Report on Form 20-F for the fiscal year ended November 30, 2005, filed with the Securities and Exchange
Commission on May 8, 2006 (the Form 20-F), for the purpose of amending Item 18. Financial Statements and Item 19. Exhibits of the Form 20-F to amend the separate financial statements of NKT
Flexibles I/S (NKT Flexibles). The financial statements of NKT Flexibles provided in Exhibit 15.2 of this Form 20-F/A reflect the consolidated statements of income and cash flows for each of the years in the three-year period ended
December 31, 2005, as required by Rule 3-09 of Regulation S-X, rather than for each of the years in the two-year period ended December 31, 2005 prepared in accordance with the accounting principles of the Danish Financial Statements Act
and as previously provided in Exhibit 15.2 to the Form 20-F.

This Form 20-F/A consists of a cover page, this explanatory note, Items 18
and 19 (as amended), the signature page and Exhibits 9.3, 12.1, 12.2, 13.1, 13.2 and 15.2.

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 May 8, 2006 or reflect any events that have occurred after the Form 20-F was filed on May 8, 2006.



|Item 18. | Financial Statements.
|-------- | ---------------------

See pages F-1 to F-55 and
S-1 to the Form 20-F, which are incorporated herein by reference.

Audited Consolidated Financial Statements of Stolt
Offshore S.A., subsequently renamed Acergy S.A.

Report of Independent Registered Public Accounting Firm.

Consolidated Statements of Operations for the fiscal years ended November 30, 2005, 2004 and 2003.

Consolidated Balance Sheets as of November 30, 2005 and 2004.

Consolidated Statements of Shareholders Equity for the fiscal years ended November 30, 2005, 2004 and 2003.

Consolidated Statements of Cash Flows for the fiscal years ended November 30, 2005, 2004 and 2003.

Notes to Consolidated Financial Statements.

Separate unaudited financial statements of EPIC JV for the fiscal year ended November 30, 2005 and audited financial statements for the fiscal year ended November 30, 2004, attached as Exhibit 15.1 to the
Form 20-F, separate unaudited financial statements of NKT Flexibles for the fiscal year ended December 31, 2005, audited financial statements for the fiscal year ended December 31, 2004 and unaudited financial statements for the fiscal
year ended December 31, 2003, attached as Exhibit 15.2 to this Form 20-F/A, and separate unaudited financial statements of Seaway Heavy Lifting for the fiscal year ended December 31, 2005, audited financial statements for the fiscal year
ended December 31, 2004 and unaudited financial statements for the fiscal year ended November 30, 2003, attached as Exhibit 15.3 to the Form 20-F, are being filed pursuant to Rule 3-09 of Regulation S-X and are incorporated herein by
reference.



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|Item 19. | Exhibits.
|-------- | ---------



|     |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
|---- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|1.1  |  | Amended and Restated Articles of Incorporation, dated as of April 3, 2006.*                                                                                                                                                                                                                                                                                                                                                                                                                                         
|     | 
|2.1  |  | Amended and Restated Deposit Agreement among the Registrant, Citibank, N.A., as Depositary, and the holders and beneficial owners from time to time of American Depositary Shares. Incorporated
by reference to Exhibit A to the Registrants Registration Statement on Form F-6 (File No. 333-90470) filed with the Securities and Exchange Commission on June 10, 2002.                                                                                                                                           
|     | 
|2.2  |  | Form of Supplemental Agreement to Deposit Agreement by and among the Registrant, Deutsche Bank Trust Company Americas, as successor depositary, and all holders and beneficial owners from time
to time of American Depositary Shares evidenced by American Depositary Receipts issued thereunder. Incorporated by reference to Exhibit 99.A2 to the Registrants Registration Statement on Form F-6 (File No. 333-123139) filed with the Securities
and Exchange Commission on March 4, 2005.                      
|     | 
|2.3  |  | Form of American Depositary Receipt (included in Exhibit 2.2).                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|     | 
|2.4  |  | Form of Indenture for the issuance of senior debt securities (including the form of senior debt securities). Incorporated by reference to Exhibit 4.2 of the Registrants registration
statement on Form F-3/A (Registration No. 333-86288), filed with the Securities and Exchange Commission on July 31, 2002.                                                                                                                                                                                                    
|     | 
|2.5  |  | Form of Indenture for the issuance of subordinated debt securities (including the form of subordinated debt securities). Incorporated by reference to Exhibit 4.3 of the Registrants
registration statement on Form F-3/A (Registration No. 333-86288), filed with the Securities and Exchange Commission on August 29, 2002.                                                                                                                                                                                      
|     | 
|4.1  |  | $350 Million Multicurrency Revolving Credit and Guarantee Facility, dated as of November 8, 2004, among Seaway (UK) Limited, as borrower, and DnB NOR Bank ASA, ING Bank N.V. and NIB Capital
Bank N.V. as arrangers, DnB NOR Bank ASA, as facility agent and security trustee and the banks listed therein. Incorporated by reference to Exhibit 4.1 to the Registrants Annual Report on Form 20-F for the fiscal year ended November 30, 2004,
filed with the Securities and Exchange Commission on May 31, 2005.
|     | 
|4.2  |  | Asset Purchase Agreement, dated April 11, 2005, by and among Cal Dive International, Inc., as Buyer, and Stolt Offshore Inc. and S&H Diving LLC, as Sellers. Incorporated by reference to
Exhibit 4.2 to the Registrants Annual Report on Form 20-F for the fiscal year ended November 30, 2004, filed with the Securities and Exchange Commission on May 31, 2005.                                                                                                                                                
|     | 
|4.3  |  | Amendment to Asset Purchase Agreement, dated as of November 1, 2005, by and among Cal Dive International, Inc., as buyer, and Stolt Offshore Inc., S&H Diving LLC and SCS Shipping Limited,
as sellers.*                                                                                                                                                                                                                                                                                                            
|     | 
|4.4  |  | Amendment No. 2 to Asset Purchase Agreement, dated as of March 1, 2006, by and between Cal Dive International, Inc., as buyer, and Stolt Offshore Inc., S&H Diving LLC and SCS Shipping
Limited, as sellers.*                                                                                                                                                                                                                                                                                                       
|     | 
|8.1  |  | Significant subsidiaries as of the end of the year covered by this Report: see Item 4. Information on the CompanySignificant Subsidiaries.*                                                                                                                                                                                                                                                                                                                                                                      
|     | 
|9.1  |  | Consent and report on schedules of Deloitte & Touche LLP, Independent Registered Public Accounting Firm.*                                                                                                                                                                                                                                                                                                                                                                                                           
|     | 
|9.2  |  | Consent of Deloitte Statsautoriserte Revisorer AS, auditors for EPIC JV.*                                                                                                                                                                                                                                                                                                                                                                                                                                           
|     | 
|9.3  |  | Consent of KPMG, auditors for NKT Flexibles I/S.                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|     | 
|9.4  |  | Consent of Deloitte Accountants B.V., auditors for Seaway Heavy Lifting Limited.*                                                                                                                                                                                                                                                                                                                                                                                                                                   
|     | 
|12.1 |  | Certification of the principal executive officer required by Rule 13a-14(a) or Rule 15d-14(a), pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                                                                                                           



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|     |  |                                                                                                                                                          
|---- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------
|12.2 |  | Certification of the principal financial officer required by Rule 13a-14(a) or Rule 15d-14(a), pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
|     | 
|13.1 |  | Certification of the Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.** 
|     | 
|13.2 |  | Certification of the Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.** 
|     | 
|14.1 |  | Consent of Elvinger, Hoss & Prussen.*                                                                                                                    
|     | 
|15.1 |  | Financial Statements of EPIC JV.*                                                                                                                        
|     | 
|15.2 |  | Financial Statements of NKT Flexibles I/S.                                                                                                               
|     | 
|15.3 |  | Financial Statements of Seaway Heavy Lifting Limited.*                                                                                                   

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|* | Previously filed with Acergys Annual Report on Form 20-F on May 8, 2006 and herein incorporated by reference.
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|** | This document is being furnished in accordance with SEC Release Nos. 33-8212 and 34-47551.
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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 No. 1 to its annual report on
Form 20-F/A on its behalf.



ACERGY S.A.By:

/s/ Mark WoolveridgeName: Mark Woolveridge Title:   Chairman of the Board of Directors




By:

/s/ Stuart JacksonName: Stuart Jackson Title:   Chief Financial Officer


Date: June 30, 2006