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Exhibit 5
SATTERLEE STEPHENS BURKE & BURKE LLP
230 Park Avenue
New York, N.Y. 10169-0079
(212) 818-9200
June 5, 2000
Medarex, Inc.
707 State Road
Suite 206
Princeton, New Jersey 08540
Dear Sirs:
You have asked for our opinion in connection with a
Registration Statement on Form S-8 to be filed with the Securities and Exchange
Commission for registration pursuant to the Securities Act of 1933, as amended
of 1,000,000 shares of common stock, par value $.01 per share, of Medarex, Inc.
(the "Company") reserved for issuance pursuant to the Company's 2000 Stock
Option Plan (the "Plan").
As counsel for the Company, we are familiar with the Plan, as
amended to date, and with the corporate proceedings relating thereto and to the
Registration Statement hereinabove referred to. Based on the foregoing, it is
our opinion that the shares reserved under the Plan, upon issuance on exercise
in accordance with the provisions of the stock option agreements evidencing
options granted thereunder, will be validly issued, fully paid and
non-assessable with no personal liability attaching to the ownership thereof
under the laws of the State of New Jersey.
We understand that a copy of this opinion will be filed as an
exhibit to the Registration Statement and we hereby consent to such filing.
/s/ SATTERLEE STEPHENS BURKE & BURKE
LLP
