-------- ----------------------------- FORM 4 OMB APPROVAL -------- ----------------------------- ----- Check this box if no longer OMB Number: 3235-0287 subject to Section 16. Form 4 Expires: January 31, 2005 ----- or Form 5 obligations may Estimated average burden continue. SEE Instruction 1(b). hours per response .... 0.5 ----------------------------- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(f) of the Investment Company Act of 1940 (Print or Type Responses) - --------------------------------------------------------------------------- 1. Name and Address of Reporting Person* Ardsley Advisory Partners - ---------------------------------------------------- (Last) (First) (Middle) 262 Harbor Drive - ---------------------------------------------------- (Street) Stamford CT 06902 - ---------------------------------------------------- (City) (State) (Zip) - --------------------------------------------------------------------------- 2. Issuer Name and Ticker or Trading Symbol OM Group, Inc. (OMG) - --------------------------------------------------------------------------- 3. IRS or Social Security Number of Reporting Person (Voluntary) - --------------------------------------------------------------------------- 4. Statement for Month/Day/Year 12/16/02 - --------------------------------------------------------------------------- 5. If Amendment, Date of Original (Month/Day/Year) - --------------------------------------------------------------------------- Page 1 of 6 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) [ ] Director [X] 10% Owner [ ] Officer (give title below) [ ] Other (specify below) - --------------------------------------------------------------------------- 7. Individual or Joint/Group Filing (Check Applicable Line) [ ] Form filed by One Reporting Person [X] Form filed by More than One Reporting Person - --------------------------------------------------------------------------- TABLE I--NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED ---------------------------------------------------------------------------- 1. Title of 2. Trans- 2A. Deemed 3. Trans- 4. Securities Acquired Security action Execution action (A) or Disposed of (D) (Instr. 3) Date Date, if Code (Instr. 3, 4 and 5) (Month/ any (Month/ (Instr. 8) ---------------------- Day/ Day/ ---------- Amount (A) or Price Year) Year) Code V (D) ---------------------------------------------------------------------------- OM Group Inc., Common Stock, $0.01 par value per share ("Common Stock") 12/16/02 P 100,000 A $6.5032 ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- Page 2 of 6 5. Amount of 6. Ownership 7. Nature of Securities Form: Direct Indirect Beneficially (D) or Indirect Beneficial Owned following (I) (Instr. 4) Ownership Reported (Instr. 4) Transactions (Instr. 3 and 4) ---------------------------------------------------------------------------- 3,150,000 I(1)(2) (1)(2) ---------------------------------------------------------------------------- Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. * If the form is filed by more than one reporting person, SEE Instruction 4(b)(v). TABLE II - DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED (E.G., PUTS, CALLS, WARRANTS, OPTIONS, CONVERTIBLE SECURITIES) ---------------------------------------------------------------------------- 1. Title of Derivative 2. Conver- 3. Transac- 4. Transac- 5. Number of Security (Instr. 3) sion or tion Date tion Code Derivative Exercise (Month/ (Instr. 8) Securities Price of Day/ ------------ Acquired (A) Deriv- Year) Code V or Disposed ative of (D) (Instr. Security 3, 4, and 5) ------------- (A) (D) ---------------------------------------------------------------------------- 6. Date Exer- 7. Title and Amount 8. Price of cisable and of Underlying Derivative Expiration Date Securities Security (Month/Day/ (Instr. 3 and 4) (Instr. 5) Year) ------------------- ----------------- Amount or Date Expira- Title Number of Exer- tion Shares cisable Date ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- Page 3 of 6 ---------------------------------------------------------------------------- 9. Number of 10. Ownership 11. Nature of Derivative Form of Indirect Securities Derivative Beneficial Beneficially Security: Ownership Owned at Direct (D) or (Instr. 4) End of Month Indirect (I) (Instr. 4) (Instr. 4) ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- Explanation of Responses (1) The shares of Common Stock to which this note relates are held directly by Ardsley Offshore Fund Ltd., a British Virgin Islands corporation ("Ardsley Offshore"), as to 775,000 shares; Ardsley Partners Fund II, L.P., a Delaware limited partnership ("Ardsley Fund II"), as to 725,000 shares; Ardsley Partners Fund I, L.P., a Delaware limited partnership ("Ardsley Fund I"), as to 425,000 shares; Ardsley Partners Institutional Fund, L.P., a Delaware limited partnership, ("Ardsley Institutional"), as to 425,000 shares; Augusta Partners L.P. a Delaware limited partnership ("Augusta"), as to 450,000 shares; and Philip J. Hempleman, the managing partner of Ardsley Advisory Partners and the general partner of Ardsley Partners I as to 350,000 shares. (2) Ardsley Advisory Partners serves as investment manager to, and has investment discretion over the securities held by Ardsley Offshore. Ardsley Advisory Partners also serves as a non-managing member of Augusta Management L.L.C., the investment advisor to Augusta and has investment discretion over the securities held by Augusta. Ardsley Partners I serves as the general partner of, and has investment discretion over the securities held by Ardsley Fund II, Ardsley Fund I and Ardsley Institutional. Ardsley Partners I also serves as the general partner of Ardsley Advisory Partners. Ardsley Advisory Partners and Ardsley Partners I each disclaim any beneficial ownership of any of the Issuer's securities to which this Form 4 relates for the purposes of Section 16 of the Securities Exchange Act of 1934, as amended, except as to such securities representing in which each such person may be deemed to have an indirect pecuniary interest pursuant to Rule 16a-1(a)(2). Page 4 of 6 * If the form is filed by more than one reporting person, SEE Instruction 4(b)(v). **Intentional misstatements or omissions of facts constitute Federal Criminal Violations. SEE 18 U.S.C. 1001 and 15 U.S.C. 78ff(a). Note: File three copies of this form, one of which must be manually signed. If space is insufficient, SEE Instruction 6 for procedure. Ardsley Advisory Partners /s/ Philip J. Hempleman 12/18/02 --------------------------------- -------- Name: Philip J. Hempleman Date Title: Managing Partner **Signature of Reporting Person Joint Filer Information Name: Ardsley Offshore Fund Ltd. Address: Romasaco Place, Wickhams Cay I, Roadtown Tortola, British Virgin Islands Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: Ardsley Offshore Fund, Ltd. By: Neil Glass, its vice president and administrative manager By: /s/ Neil Glass ------------------------------------------------------------- Name: Neil Glass Title: Vice President and Administrative Manager Name: Ardsley Partners Fund II, L.P. Address: 262 Harbor Drive, Stamford, Connecticut 06902 Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: Ardsley Partners Fund II, L.P. By: Ardsley Partners I, its general partner By: /s/ Philip J. Hempleman ----------------------------------------------------------- Name: Philip J. Hempleman Title: General Partner Name: Ardsley Partners Fund I, L.P. Address: 262 Harbor Drive, Stamford, Connecticut 06902 Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: Ardsley Partners Fund I, L.P. By: Ardsley Partners I, its general partner By: /s/ Philip J. Hempleman ----------------------------------------------------------- Name: Philip J. Hempleman Title: General Partner Page 5 of 6 Name: Ardsley Partners Institutional Fund, L.P. Address: 262 Harbor Drive, Stamford, Connecticut 06902 Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: Ardsley Partners Institutional Fund, L.P. By: Ardsley Partners I, its general partner By: /s/ Philip J. Hempleman ----------------------------------------------------------- Name: Philip J. Hempleman Title: General Partner Name: Augusta Partners L.P. Address: 622 Third Avenue, New York, New York 10017 Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: Augusta Partners L.P. By: Howard Singer, its general partner By: /s/ Howard Singer ----------------------------------------------------------- Name: Howard Singer Title: General Partner Name: Ardsley Partners I Address: 262 Harbor Drive, Stamford, Connecticut 06902 Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: Ardsley Partners I By: /s/ Philip J. Hempleman ----------------------------------------------------------- Name: Philip J. Hempleman Title: General Partner Name: Philip J. Hempleman Address: c/o Ardsley Advisory Partners 262 Harbor Drive, Stamford, Connecticut 06902 Designated Filer: Ardsley Advisory Partners Issuer & Ticker Symbol: OM Group, Inc.(OMG) Date of Event Requiring Statement: 12/16/02 Signature: /s/ Philip J. Hempleman ----------------------------------------------------------- Name: Philip J. Hempleman Page 6 of 6