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                                                  OMB Number           3235-0287
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                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 of Section 16. Form 4 or Form 5 obligations
     may continue. See Instruction 1(b).

________________________________________________________________________________
1.   Name and Address of Reporting Person*

Caruso,                               John                    A.
- --------------------------------------------------------------------------------
   (Last)                           (First)             (Middle)

20 Kingsbridge Road
- --------------------------------------------------------------------------------
                                    (Street)

Piscataway                           NJ                    08854
- --------------------------------------------------------------------------------
   (City)                           (State)              (Zip)


________________________________________________________________________________
2.   Issuer Name and Ticker or Trading Symbol


Enzon, Inc. (ENZN)
________________________________________________________________________________
3.   IRS Identification Number of Reporting Person, if an Entity (Voluntary)



________________________________________________________________________________
4.   Statement for Month/Year


July 1998
________________________________________________________________________________
5.   If Amendment, Date of Original (Month/Year)


================================================================================
6.   Relationship of Reporting Person to Issuer
     (Check all applicable)

     [_]  Director                             [_]  10% Owner
     [X]  Officer (give title below)           [_]  Other (specify below)

     Vice President, Business Development, Secretary and General Counsel
________________________________________________________________________________
7.   Individual or Joint/Group Filing (Check applicable line)

     [X]  Form filed by one Reporting Person
     [_]  Form filed by more than one Reporting Person
________________________________________________________________________________


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           Table I -- Non-Derivative Securities Acquired, Disposed of,
                             or Beneficially Owned
================================================================================
6. 4. 5. Owner- Securities Acquired (A) or Amount of ship 3. Disposed of (D) Securities Form: 7. Transaction (Instr. 3, 4 and 5) Beneficially Direct Nature of 2. Code ------------------------------- Owned at End (D) or Indirect 1. Transaction (Instr. 8) (A) of Month Indirect Beneficial Title of Security Date ------------ Amount or Price (Instr. 3 (I) Ownership (Instr. 3) (mm/dd/yy) Code V (D) and 4) (Instr.4) (Instr. 4) - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ ====================================================================================================================================
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 conrol 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) ================================================================================
10. 9. Owner- Number ship of Form 2. Deriv- of Conver- 5. 7. ative Deriv- 11. sion Number of Title and Amount Secur- ative Nature or Derivative 6. of Underlying 8. ities Secur- of Exer- 4. Securities Date Securities Price Bene- ity: In- cise 3. Trans- Acquired (A) Exercisable and (Instr. 3 and 4) of ficially Direct direct Price Trans- action or Disposed Expiration Date ---------------- Deriv- Owned (D) or Bene- 1. of action Code of(D) (Month/Day/Year) Amount ative at End In- ficial Title of Deriv- Date (Instr. (Instr. 3, ---------------- or Secur- of direct Owner- Derivative ative (Month/ 8) 4 and 5) Date Expira- Number ity Month (I) ship Security Secur- Day/ ------ ------------ Exer- tion of (Instr. (Instr. (Instr. (Instr. (Instr. 3) ity Year) Code V (A) (D) cisable Date Title Shares 5) 4) 4) 4) - ------------------------------------------------------------------------------------------------------------------------------------ Stock Option Common (right to buy)(a) $6.50 7/21/98 A V 50,000 (b) 7/21/08 Stock 50,000 260,992 D - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------------------------------------------ ====================================================================================================================================
Explanation of Responses: /S/ JOHN A. CARUSO 9/1/98 - --------------------------------------------- ----------------------- **Signature of Reporting Person Date (a) Granted under the Company's Non-qualified Stock Option Plan and qualified under Rule 16b-3. (b) Options vest in two tranches of 25,000 shares each on July 21, 1999 and July 21, 2000. ** 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)