U.S. SECURITIES AND EXCHANGE COMMISSION
Washington, DC 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).
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1. Name and Address of Reporting Person*
Rosenwald, Lindsay A.
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(Last) (First) (Middle)
c/o Paramount Capital Asset Management, Inc.,
787 Seventh Avenue, 48th Floor
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(Street)
New York NY 10019
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(City) (State) (Zip)
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2. Issuer Name and Ticker or Trading Symbol
Repligen Corporation (RGEN)
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3. IRS Identification Number of Reporting Person, if an Entity (Voluntary)
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4. Statement for Month/Year
December 2000
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5. If Amendment, Date of Original (Month/Year)
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6. Relationship of Reporting Person to Issuer
(Check all applicable)
|_| Director |X| 10% Owner
|_| Officer (give title below) |_| Other (specify below)
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7. Individual or Joint/Group Filing (Check Applicable Line)
|_| Form filed by one Reporting Person
|X| Form filed by more than one Reporting Person
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* If the Form is filed by more than one Reporting Person, see Instruction
4(b)(v).
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Table I -- Non-Derivative Securities Acquired, Disposed of,
or Beneficially Owned
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<TABLE>
<CAPTION>
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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<S> <C> <C> <C> <C> <C> <C> <C> <C> <C>
By The Aries Master
Common Stock 12/05/00 P 6,069 A $4.063 4,924,200(1) I Fund II(1)
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Page 1 of 5
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By The Aries Master
Common Stock 12/19/00 P 1,000 A $4.590 4,924,200(1) I Fund II(1)
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By The Aries Master
Common Stock 12/20/00 P 12,106 A $3.390 4,924,200(1) I Fund II(1)
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By Aries Domestic
Common Stock 12/01/00 P 1,000 A $4.591 4,924,200(1) I Fund, L.P.(1)
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By Aries Domestic
Common Stock 12/05/00 P 2,933 A $4.063 4,924,200(1) Fund, L.P.(1)
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By Aries Domestic
Common Stock 12/20/00 P 5,788 A $3.390 4,924,200(1) I Fund, L.P.(1)
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By Aries Domestic
Common Stock 12/05/00 P 998 A $4.063 4,924,200(1) I Fund II, L.P.(1)
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By Aries Domestic
Common Stock 12/20/00 P 2,106 A $3.390 4,924,200(1) I Fund II, L.P.(1)
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</TABLE>
Reminder: Report on a separate line for each class of securities beneficially
owned directly or indirectly.
Page 2 of 5
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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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<TABLE>
<CAPTION>
9. 10.
Number Owner-
of ship
2. Deriv- Form of
Conver- 5. 7. ative Deriv- 11.
sion Number of Title and Amount Secur- ative Nature
of 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) 5) 5)
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<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
Aries
Domestic
Put (Long) $10 12/01/00 P 10 Immed. 03/16/01 Common 1,000 $5.41 43 I Fund, L.P.(2)
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</TABLE>
Page 3 of 5
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Explanation of Responses:
** Intentional misstatements or omissions of facts constitute Federal Criminal
Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) See Attachment A
(2) Paramount Capital Asset Management, Inc. ("PCAM") is the general partner of
each of the Aries Domestic Fund, L.P. ("Aries I") and Aries Domestic Fund II,
L.P. ("Aries II"), each a Delaware limited partnership, and also serves as the
investment manager of the Aries Master Fund II, a Cayman Island exempted company
(the "Master Fund"), which also owns securities of the Issuer. Dr. Rosenwald is
the chairman and sole stockholder of PCAM. As a result, Dr. Rosenwald and PCAM
may be deemed to have voting and investment control over the securities of the
issuer owned by the Aries Funds under Rule 16a-(a)(1) of the Securities Exchange
Act of 1934. Dr. Rosenwald and PCAM disclaim beneficial ownership of the
securities held by the Aries Funds, except to the extent of its pecuniary
interest therein, if any.
/s/ Lindsay Rosenwald January 9, 2001
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** Signature of Reporting Person Date
Lindsay A. Rosenwald, M.D.
Chairman
Paramount Capital Asset Management, Inc.
Investment Manager - Aries Master Fund II
General Partner - Aries Domestic Fund L.P.
General Partner - Aries Domestic Fund II, L.P.
Note: File three copies of this Form, one of which must be manually signed. If
space provided is insufficient, see Instruction 6 for procedure.
Page 4 of 5
<PAGE>
ATTACHMENT A
Securities beneficially owned by Dr. Rosenwald are presented on an as-converted
basis and consist of the following:
1. 3,319,545 shares of common stock of the Issuer, par value $0.01 per share
(the "Common Stock") owned by The Aries Master Fund, a Cayman Island
Exempted Company (the "Master Fund")
2. 1,345,795 shares of Common Stock of the Issuer owned by Aries Domestic
Fund, L.P. ("Aries I")
3. 225,610 shares of Common Stock owned by Aries Domestic Fund II, L.P.
("Aries II" and collectively with Aries I and the Master Fund, the "Aries
Funds")
4. Warrants to purchase 33,250 shares of Common Stock owned directly by Dr.
Rosenwald.
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