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OMB Number  3235-0287
Expires:  September 30, 1998
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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 this box if no longer subject to Section 16. Form 4 or Form 5
obligations may continue. See Instruction 1(b).

(Print or Type Repsonses)
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1.   Name and Address of Reporting Person*

Tombros                          Peter         
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(Last)                           (First)             (Middle)

c/o Enzon, Inc., 20 Kingsbridge Road
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(Street)

Piscataway,                      New Jersey           08854
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(City)                           (State)              (Zip)

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2.   Issuer Name and Ticker or Trading Symbol

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

________________________________________________________________________________
4.   Statement for Month/Year

November 2000
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5.   If Amendment, Date of Original (Month/Year)

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

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

President and Chief Executive Officer
________________________________________________________________________________
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
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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)
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Common Stock                         11/14/00        M             30,000        A     $2.6875                      
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Common Stock                         11/14/00        S             30,000        D     $65.0000                     
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Common Stock                         11/15/00        M             32,000        A     $2.6875                      
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Common Stock                         11/15/00        S             32,000        D     $65.1000                     
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Common Stock                         11/27/00        M             15,000        A     $2.6875                      
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Common Stock                         11/27/00        S             15,000        D     $66.0000 30,300            D               
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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 control 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)

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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)
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Stock Option (a)                                                               Common
(right to buy)      $2.6875  11/14/00  M             30,000  9/30/97  9/29/02  Stock     30,000   --
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Stock Option (a)                                                               Common
(right to buy)      $2.6875  11/15/00  M             32,000  9/30/97  9/29/02  Stock     32,000   --
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Stock Option (a)                                                               Common
(right to buy)      $2.6875  11/27/00  M             15,000  9/30/97  9/29/02  Stock     15,000   --      23,000     D
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Explanation of Responses:
(a)  Granted under the Company's Non-qualified Stock Option Plan and qualified
under Rule 16b-3.

/s/ Peter Tombros                                        10/7/00
-------------------------------                          -----------   
**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 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.