SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13D (RULE 13d-101) INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO 13D-2(A) (AMENDMENT NO. 4) NALCO HOLDING COMPANY ------------------------------------------------------------------------------- (Name of Issuer) COMMON STOCK, PAR VALUE $0.01 ------------------------------------------------------------------------------- (Title of Class of Securities) 62985Q 10 1 ------------------------------------------------------------------------------- (CUSIP Number) Stephen N. Landsman Vice President, General Counsel & Corporate Secretary Nalco LLC 1601 W. Diehl Road Naperville, IL 60563 Phone: 630-305-1554 ------------------------------------------------------------------------------- (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) DECEMBER 30, 2005 ------------------------------------------------------------------------------- (Date of Event Which Requires Filing of This Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box. |_| Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent. The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page. The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). 1 of 5 -------------------------------------------------------------------------------- 1 Name of Reporting Person I.R.S. IDENTIFICATION OF ABOVE PERSON Nalco LLC -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS OO -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 15,094,930 shares of Common Stock (see Item 5) ------------------------------------------------------------ NUMBER OF SHARES 8 SHARED VOTING POWER BENEFICIALLY OWNED BY EACH 0 REPORTING PERSON ------------------------------------------------------------ WITH 9 SOLE DISPOSITIVE POWER 15,094,930 shares of Common Stock (see Item 5) ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 0 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 15,094,930 shares of Common Stock (see Item 5) -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 10.6% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON OO -------------------------------------------------------------------------------- CUSIP No. 62985Q 10 1 13D Page 2 of 5 Page 2 of 5 This Amendment No. 4 supplements and amends Item 5 of the Statement on Schedule 13D filed on November 24, 2004, as amended by (i) Amendment No. 1 to the Statement on Schedule 13D filed on August 19, 2005, (ii) Amendment No. 2 to the Statement on Schedule 13D filed on August 24, 2005 and (iii) Amendment No. 3 to the Statement on Schedule 13D filed on December 22, 2005 (as so amended, the "Statement on Schedule 13D") by Nalco LLC, a Delaware limited liability company ("Nalco LLC"), relating to the shares of common stock, par value $0.01 (the "Common Stock"), of Nalco Holding Company (the "Issuer"). Unless otherwise indicated, each capitalized term used but not otherwise defined herein shall have the meaning assigned to such term in the Statement on Schedule 13D. ITEM 5. INTEREST IN SECURITIES OF THE ISSUER Item 5 is hereby amended and supplemented by deleting it in its entirety and replacing it with the following: On December 30, 2005, Nalco LLC made a distribution of an aggregate of 38,029,261 shares of the Issuer's common stock to the members of Nalco LLC that qualify as a "venture capital operating company" (as defined in 29 C.F.R. sec. 2510.3-101(d)) in proportion to their membership interests pursuant to the terms of the previously reported Stockholders Agreement. Following such distribution, Nalco LLC is the record holder of 15,094,930 shares of Common Stock, which represents approximately 10.6% of the outstanding Common Stock of the Issuer. Page 3 of 5 (a) See the information contained on the cover pages to this Amendment No. 4 to Schedule 13D, which is incorporated herein by reference. The percentage of the class beneficially owned by Nalco LLC is based on 142,737,451 outstanding shares of Common Stock of the Issuer as of December 30, 2005. (b) See the information contained on the cover pages to this Amendment No. 4 to Schedule 13D, which is incorporated herein by reference. (c) Except for the information set forth herein or in Amendment No. 3 to Schedule 13D, or incorporated by reference herein, Nalco LLC has not effected any transaction relating to the Common Stock during the past 60 days. (d) In accordance with the terms of the Nalco LLC Limited Liability Company Operating Agreement, and if approved by the board of directors of Nalco LLC, the members of Nalco LLC have the right to receive dividends from and the proceeds from any sale of Common Stock in accordance with their membership interests in Nalco LLC. (e) Not applicable. Page 4 of 5 SIGNATURE After reasonable inquiry and to the best knowledge and belief I certify that the information set forth in this statement is true, complete and correct. Date: January 4, 2006 NALCO LLC By: /s/ Stephen N. Landsman --------------------------------------- Name: Stephen N. Landsman Title: Vice President, General Counsel & Corporate Secretary Page 5 of 5