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EXHIBIT 10.283
LOCK-UP AGREEMENT
This agreement, effective as of January
___, 2005, is made by and between LIGAND
PHARMACEUTICALS INCORPORATED ("Ligand" or
the "Company") and each of the
undersigned individuals. When executed,
this document shall evidence separate
agreements between the Company and each of
the undersigned.
In connection with the proposed option
acceleration approved by the Compensation
Committee of the Board of Directors on
January 20, 2005 subject to certain
contingencies, each of the undersigned
hereby agrees with the Company as
follows:
Upon any acceleration pursuant to the above
authorization:
1.
Accelerated options may be exercised any time after the
acceleration
date, under the terms of the existing Stock Option Agreements
and
Notices of Option Grant;
2.
Provided
however, that any shares acquired pursuant to an
accelerated option may not be sold, transferred or otherwise
disposed of prior to the date those shares would have vested un
