UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

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Form 10-K/A

Amendment No. 1
to
Form 10-K

|(Mark One) |                                                                                         
|---------- | ----------------------------------------------------------------------------------------
|ý          | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934    
|           | For the fiscal year ended December 31, 2003                                             
|or        
|o          | TRANSITION REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|           | For the transition period from                  to                                      

Commission file number 0-15325

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Ascential Software Corporation(formerly Informix Corporation)(Exact name of registrant as specified in its charter)

|Delaware(State or other jurisdiction of
incorporation or organization)                    |  | 94-3011736(I.R.S. Employer
Identification No.)
|----------------------------------------------------------------------------------------- |  | ----------------------------------------------
|50 Washington Street,
Westborough, MA(Address of principal executive office)              |  | 01581(Zip Code)                               
|(Registrant's telephone number, including area code)
508-366-3888                        
|Securities registered pursuant to Section 12(b) of the Act: None                         
|Securities registered pursuant to Section 12(g) of the Act:
Common Stock, $0.01 par value

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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 ý    No o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of
Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in
Part III of this Form 10-K or any amendment to this Form 10-K. ý

Indicate by check mark whether the registrant is an accelerated filer (as defined in Exchange Act
Rule 12b-2). Yes ý    No o

The aggregate market value of the voting stock held by non-affiliates of the registrant as of
June 30, 2003 based on the closing sales price of the Company's common stock, as reported on The NASDAQ Stock Market, was $691.9 million. Shares of common stock held by each executive
officer and director have been excluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not intended as a conclusive determination for any other purpose.

As of February 27, 2004, the registrant had 60,280,710 shares of Common Stock issued and
outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant's definitive proxy statement for its annual meeting of stockholders for the fiscal year ended December 31, 2003, which will be
filed with the Securities and Exchange Commission within 120 days after the end of the registrant's fiscal year, are incorporated by reference into Part III hereof.



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This Amendment No. 1 on Form 10-K/A to the Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2003 (the "Form
10-K") is being filed to add Exhibit 23.2, which was inadvertently omitted, due to a technical error, from the electronically filed Form 10-K as filed with the Securities and Exchange
Commission on March 15, 2004.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this
Amendment No. 1 on Form 10-K/A to be signed on its behalf by the undersigned, thereunto duly authorized.

|                     |  | ASCENTIAL SOFTWARE CORPORATION
|-------------------- |  | ------------------------------
|Date: March 16, 2004 |  | By:                           

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