Form of Lock-Up
Agreement
_____________ __, 2007
Healthcare
Acquisition Corporation
2116 Financial
Center
666 Walnut
Street
Des Moines,
Iowa 50309
Re:
Healthcare Acquisition
Corp./PharmAthene, Inc. Merger
Ladies and
Gentlemen:
This letter agreement (this
“Agreement”) relates to the proposed merger (the
“Merger”) of PAI Acquisition Corp. (the “Merger
Sub”), a Delaware corporation and a wholly-owned subsidiary
of Healthcare Acquisition Corporation (the “Parent”), a
Delaware corporation, with PharmAthene, Inc. (the
“Company”), a Delaware corporation. The Merger is
governed by the certain Agreement and Plan of Merger, dated as of
January __, 2007, by and among Parent, Merger Sub and the Company
(the “Merger Agreement”) and capitalized terms not
otherwise defined herein shall have the meanings ascribed to such
terms in the Merger Agreement.
In order to induce Parent and Merger Sub to
consummate the Merger, the undersigned hereby agrees that, as of
the date hereof until expiration of the Lock-Up Period (as defined
below), the undersigned: (a) will not, directly or indirectly,
offer, sell, agree to offer or sell, solicit offers to purchase,
grant any call option or purchase any put option with respect to,
pledge, borrow or otherwise dispose of any Relevant Security (as
defined below) and (b) will not establish or increase any
“put equivalent position” or liquidate or decrease any
“call equivalent position” with respect to any Relevant
Security (in each case within the meaning of Section 16 of the
Securities Exchange Act of 1934, as amended, and the rules and
regulations promulgated thereunder) or otherwise enter into any
swap, derivative or other transaction or arrangement that transfers
to another, in whole or in part, any economic consequence of
ownership of a Relevant Security, whether or not such transaction
is to be settled by delivery of Relevant Securities, other
securities, cash or other consideration, except in accordance with
the following schedule: fifty percent (50%) of the Relevant
Securities shall be released from this Agreement on the date that
is six (6) months from the Closing Date and the remaining fifty
percent (50%) of the Relevant Securities shall be released from
this Agreement on the date that is twelve (12) months from the
Closing Date (the “Lock-Up Period”). As used herein,
“Relevant Security” means any common stock or 8%
promissory notes of the Parent (or common stock issuable upon
conversion of such notes or as a dividends thereon) received by or
issuable to the undersigned pursuant to the Merger
Agreement.
The undersigned hereby authorizes Parent during
the Lock-Up Period to cause any transfer agent for the Relevant
Securities to decline to transfer and to note stop transfer
restrictions on the stock register and other records relating to
Relevant Securities for which the undersigned is the record holder
and, in the case of Relevant Securities for which the undersigned
is the beneficial but not record holder, agrees during the Lock-Up
Period to cause the record holder to authorize the Parent to cause
any transfer agent for the Relevant Securities to decline to
transfer and to note stop transfer restrictions on the stock
register and other records relating to such Relevant Securities in
accordance with this Agreement.
The restrictions set forth in the immediately
preceding paragraph shall not apply to:
(1) if the undersigned is a natural person, any
transfers made by the undersigned (a) as a bona fide gift to
any member of the immediate family (as defined below) of the
undersigned or to a trust the direct or indirect beneficiaries of
which are exclusively the undersigned or members of the
undersigned’s immediate family, (b) by will or intestate
succession upon the death of the undersigned or (c) as a bona
fide gif
