February 22, 2000
Morgan Stanley & Co. Incorporated
SG Cowen Securities Corporation
CIBC World Markets Corp.
c/o Morgan Stanley & Co. Incorporated
1585 Broadway
New York, NY 10036
Dear Sirs and Mesdames:
The undersigned understands that Morgan Stanley & Co. Incorporated
("MORGAN STANLEY") proposes to enter into an Underwriting Agreement (the
"UNDERWRITING AGREEMENT") with Enzon, Inc., a Delaware corporation (the
"COMPANY"), providing for the public offering (the "PUBLIC OFFERING") by the
several Underwriters, including Morgan Stanley (the "UNDERWRITERS"), of up to
2,300,000 shares (the "SHARES") of the Common Stock, $.01 par value, of the
Company (the "COMMON STOCK").
The undersigned are the beneficial holders of 118,700 shares of Common
Stock, including (i) 20,000 shares of Common Stock issuable upon exercise of
stock options held by Mr. MacKinnon, (ii) 31,700 shares of Common Stock held by
Mr. MacKinnon through the Aleck M. MacKinnon Revocable Trust (Mr. MacKinnon,
trustee), (iii) 7,800 shares of Common Stock previously held by Mr. MacKinnon
through the Aleck M. MacKinnon Revocable Trust and currently held by a brokerage
firm pending transfer to a charitable trust, (iv) 19,900 shares of Common Stock
held through the Marion L. MacKinnon Revocable Trust (Mrs. MacKinnon, trustee),
(v) 11,800 shares of Common Stock previously held by Mrs. MacKinnon through the
Marion L. MacKinnon Revocable Trust and currently held by a brokerage firm
pending transfer to a charitable trust, (vi) 4,850 shares of Common Stock held
though the Aleck M. MacKinnon Irrevocable Trust (Mrs. Mac Kinnon, trustee),
(vii) 5,850 shares of Common Stock held through the Marion L. MacKinnon
Irrevocable Trust (Mr. MacKinnon, trustee), (viii) 11,800 shares of Common Stock
held through the MacKinnon Family Charitable Foundation (Mr. MacKinnon,
trustee), and (ix) 5,000 shares held through the MacKinnon 1999 Grandchildren
Trust (Mr. MacKinnon, trustee). The undersigned or his spouse has previously
transferred additional shares of Common Stock to certain trusts and no longer
have beneficial ownership of the shares held by such trusts.
To induce the Underwriters that may participate in the Public Offering
to continue their efforts in connection with the Public Offering, the
undersigned hereby agrees that, without the prior written consent of Morgan
Stanley on behalf of the Underwriters, the undersigned will not, during the
period commencing on the date hereof and ending 90 days after the date of the
final prospectus relating to the Public Offering (the "PROSPECTUS"), (1) offer,
pledge, sell, contract to sell, sell any option or contract to purchase,
purchase any option or contract to sell, grant any option, right or warrant to
purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any
shares of Common Stock or any securities convertible into or exercisable or
exchangeable for Common Stock or (2) enter into any swap or other arrangement
that transfers to another, in whole or in part, any of the economic consequences
of ownership of the Common Stock, whether any such transaction described in
clause (1) or (2) above is to be settled by delivery of Common Stock or such
other securities, in cash or otherwise. The foregoing sentence shall not apply
to (A) transactions relating to shares of Common Stock or other securities
acquired in open market transactions after the completion of the Public Offering
or (B) transactions relating to the sale of up to 15,000 shares of Common Stock,
provided any sale of the shares shall have been made through Morgan Stanley and
shall not have been sold during the period commencing one week before the
effective date of the Company's Registration Statement on Form S-3 relating to
the Public Offering (the "EFFECTIVE DATE") and ending two weeks after the
Effective Date. The Company shall notify the undersigned at least ten business
days prior to the Effective Date.
In addition, the undersigned agrees that, without the prior written
consent of Morgan Stanley on behalf of the Underwriters, it will not, during the
period commencing on the date hereof and ending 90 days after the date of the
Prospectus, make any demand for or exercise any right with respect to, the
registration of any shares of Common Stock or any security convertible into or
exercisable or exchangeable for Common Stock.
This agreement and the obligations of the undersigned hereunder shall
be terminated if the registration statement to be filed by the Company, relating
to the Shares of Common Stock in the Public Offering, is not declared effective
by the Securities Exchange Commission on or before June 30, 2000.
Whether or not the Public Offering actually occurs depends on a number
of factors, including market conditions. Any Public Offering will only be made
pursuant to an Underwriting Agreement, the terms of which are subject to
negotiation between the Company and the Underwriters.
Very truly yours,
Aleck M. MacKinnon,
individually and as trustee
/s/ Aleck M. MacKinnon
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Aleck M. MacKinnon
4980 Dockside Drive, #201
Ft. Myers, FL 33919
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(Address)
Marion L. MacKinnon,
individually and as trustee
/s/ Marion M. MacKinnon
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Marion L. MacKinnon
4980 Dockside Drive, #201
Ft. Myers, FL 33919
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(Address)