------------------------------ OMB APPROVAL ----------------------------- OMB Number 3235-0287 Expires: September 30, 1998 Estimated average burden hours per response ....... 0.5 ----------------------------- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 4 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 [_] Check box if no longer subject to Section 16, Form 4 or Form 5 obligations may continue. See Instruction 1(b). (Print or Type Responses) ________________________________________________________________________________ 1. Name and Address of Reporting Person* Thurman, Ralph H. -------------------------------------------------------------------------------- (Last) (First) (Middle) c/o Enzon, Inc., 20 Kingsbridge Road -------------------------------------------------------------------------------- (Street) Piscataway, New Jersey 08854 -------------------------------------------------------------------------------- (City) (State) (Zip) ________________________________________________________________________________ 2. Issuer Name and Ticker or Trading Symbol ENZON, INC. (ENZN) ________________________________________________________________________________ 3. I.R.S Identification Number of Reporting Person, if an entity (Voluntary) ________________________________________________________________________________ 4. Statement for Month/Year November 2001 ________________________________________________________________________________ 5. If Amendment, Date of Original (Month/Year) ________________________________________________________________________________ 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) [X] Director [_] 10% Owner [_] Officer (give title below) [_] Other (specify below) ________________________________________________________________________________ 7. Individual or Joint/Group Filing (Check Applicable Line) [X] Form filed by One Reporting Person [_] Form filed by More than one Reporting Person ________________________________________________________________________________ ================================================================================ Table I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned ================================================================================

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). Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number. (Over) SEC 1474(7-97) FORM 4 (continued) Table II -- Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities) ================================================================================

Explanation of Responses: (a) Acquired pursuant to the Company's Non-Qualified Stock Option Plan and qualified under Rule 16b-3. (b) 20,000 options became exercisable on each of January 2, 1998, January 2, 1999 and January 2, 2000. /s/ R.H. THURMAN December 3, 2001 ------------------------------- ---------------- **Signature of Reporting Person Date ** 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 provided is insufficient, see Instruction 6 for procedure. Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number. Page 2 SEC 1474(7-97)

THURMAN RANDY 4