WAIVER NO. 5
Reference is made to the Employment Agreement dated as
of November 6, 1996 between Seragen, Inc. (the "Company") and the undersigned,
as amended (collectively the "Agreement"). Pursuant to the Agreement and
subsequent waivers, the Company agreed to file on or before December 31, 1997,
a registration statement on Form S-8 (the "Registration Statement")
registering under the Securities Act of 1993 all shares issued or to be issued
pursuant to the exercise of the stock options granted to Mr. Prior pursuant to
the Agreement.
The undersigned waives the Company's obligation under
the Agreement to file the Registration Statement by the December 31, 1997
deadline, and agrees that the Company will have met its obligations under the
Agreement to file the Registration Statement if the Registration Statement is
filed on or before July 1, 1998.
Except as expressly waived in this Waiver No. 5, all
other obligations of the Company contained in the Agreement shall remain in
full force and in effect.
EXECUTED as of the 5th day of February, 1998.
/s/ Reed R. Prior
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Reed R. Prior
