May 11, 1998
Ligand Pharmaceuticals Incorporated
00000 Xxxxxxx Xxxxxx Xxxxx
Xxx Xxxxx, XX 00000
Ladies and Gentlemen:
The undersigned is a stockholder of Seragen, Inc., a Delaware corporation
("Seragen"). The undersigned understands that Seragen, Ligand Pharmaceuticals
Incorporated, a Delaware corporation ("Ligand"), and Knight Acquisition
Corporation, a Delaware Corporation ("Merger Sub"), have entered into an
Agreement and Plan of Reorganization, dated as of May 11, 1998 (the
"Reorganization Agreement"), which provides for the merger (the "Merger") of
Merger Sub into Seragen. The undersigned also understands that Ligand, at its
option, may provide some or all of the Merger Consideration (as defined in the
Reorganization Agreemnt) in the form of shares of voting common stock, par
value $.001 per share, of Ligand (the "Common Stock"). The undersigned further
understands that the issuance of the Common Stock pursuant to the terms of the
Merger will be the subject of a registration statement under the Securities
Act of 1933, as amended (the "Registration Statement"), which will be filed
with the Securities and Exchange Commission and which will contain a prospectus
relating to the Merger (the "Prospectus").
In consideration of the execution of the Reorganization Agreement by
Xxxxxx and Merger Sub, and for other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the undersigned hereby
agrees that from the date of issuance of the Common Stock pursuant to the
Reorganization Agreement, if such issuance occurs, any shares of Common Stock
issued pursuant to the Reorganization Agreement (the "Merger Shares") shall
be subject to the transfer restrictions set forth in Section 4.1 of that
certain Stock Purchase Agreement dated November 25, 1997 between the
undersigned and Ligand (the "Purchase Agreement"), as if the Merger Shares
were Shares (as defined in the Purchase Agreement), for the periods of time
set forth in Section 4.1 of the Purchase Agreement.
It is understood and agreed that the foregoing agreement is provided as
an inducement to, and may be relied upon by, Ligand, Seragen and Merger Sub in
connection with (a) their consummation of the Merger and (b) their preparation
and distribution of the Registration Statement and the Prospectus.
Xxxxxxx and Boston Equiserv, as transfer agent for Seragen, and Ligand and
ChaseMellon Shareholder Services LLC, as the transfer agent for Ligand, are
each hereby authorized to enforce the terms of this letter by refusing to permit
transfers of Common Stock which Xxxxxx concludes may violate the terms of this
letter.
This letter may be executed in one or more counterparts, each of which
shall be deemed an original, but all of which together shall constitute a single
instrument.
Sincerely,
XXX XXXXX AND COMPANY
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Signature
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Printed Name
Accepted and agreed to as of the date first
written above:
LIGAND PHARMACEUTICALS INCORPORATED
By:
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Title:
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