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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 Responses)
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1.   Name and Address of Reporting Person*

Thurman                           Ralph                  H.  
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(Last)                           (First)             (Middle)

c/o Enzon, Inc., 20 Kinsbridge 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

September 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
[_]  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
________________________________________________________________________________

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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          ------------                 or              (Instr. 3      (I)       Ownership
(Instr. 3)                            (mm/dd/yy)     Code     V     Amount       (D)    Price    and 4)         (Instr.4) (Instr. 4)
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Common Stock                          9/8/00          M             10,000        A     $2.0625                    D
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Common Stock                          9/8/00          S             10,000        D     $61.50                     D
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Common Stock                          9/8/00          M             10,000        A     $3.5625                    D
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Common Stock                          9/8/00          S             10,000        D     $61.50                     D
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Common Stock                          9/28/00         M             50,000        A     $3.5625                    D
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Common Stock                          9/28/00         S             50,000        D     $69.875  16,268(1)         D
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(1) The aggregate number of shares beneficially owned by Mr. Thurman as of July
31, 2000 was previously incorrectly reported as 16,245. The aggregate number of
shares benefically owned by Mr. Thurman as of July 31, 2000 was 16,268.

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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Common Stock        2.0625   9/8/00    M              10,000 8/21/95  2/21/05  Common    10,000            0        D
(right to buy)(2)                                                              Stock
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Common Stock        3.5625   9/8/00    M              10,000 4/19/96  4/19/06  Common    10,000            0        D
(right to buy)(2)                                                              Stock
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Common Stock        3.5625   9/28/00   M              50,000 4/19/97  4/19/06  Common    50,000           40,000    D
(right to buy)(2)                                                              Stock
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Explanation of Responses:
(2) Acquired pursuant to the Company's Non-Qualified Stock Option Plan and 
qualified under Rule 16b-3.

/s/ Ralph H. Thurman                                     10/09/00
-------------------------------                          -----------   
**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.