Exhibit 4.1  FORM OF SPECIMEN OF COMMON STOCK CERTIFICATE  FACE OF DOCUMENT  MC  MEDAREX, INC.  INCORPORATED UNDER THE LAWS OF THE STATE OF NEW JERSEY  COMMON STOCK  CUSIP 583916 10 1  SEE REVERSE FOR CERTAIN DEFINITIONS  THIS CERTIFIES THAT  is the owner of  FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK OF THE PAR VALUE
OF $.01 EACH OF  MEDAREX, INC.  transferable on the books of the Corporation by the holder hereof in
person or by a duly authorized attorney upon surrender of the Certificate
properly endorsed. This Certificate and the shares represented hereby are
issued and shall be subject to all the provisions of the Certificate of
Incorporation of the Corporation, as now or hereafter amended, to all of which
the holder hereof by acceptance hereof assents. This Certificate is not valid
unless countersigned by the Transfer Agent.  WITNESS the facsimile seal of the Corporation and the facsimile
signatures of its authorized officers.  Dated:  [SEAL]  [SIGNATURE] SECRETARY  [SIGNATURE] PRESIDENT  COUNTERSIGNED: CONTINENTAL STOCK TRANSFER & TRUST COMPANY


(JERSEY CITY, N.J.) BY TRANSFER AGENT AUTHORIZED OFFICER  BACK OF DOCUMENT  THE CORPORATION IS AUTHORIZED TO ISSUE COMMON STOCK, PAR VALUE $.01 PER
SHARE AND PREFERRED STOCK, PAR VALUE $1.00 PER SHARE. THE CORPORATION WILL
FURNISH TO ANY SHAREHOLDER, UPON REQUEST AND WITHOUT CHARGE, A FULL STATEMENT
OF THE DESIGNATIONS, RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF EACH SUCH CLASS AS
WELL AS THE AUTHORITY OF THE BOARD OF DIRECTORS TO EFFECT SUCH CLASSES OR ANY
SERIES THEREOF.  The following abbreviations, when used in the inscription on the face
of this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:  TEN COM-as tenants in common TEN ENT-as tenants by the entireties JT TEN-as joint tenants with right of survivorship and not as tenants
in common  UNIF GIFT MIN ACT-                       
  Custodian(Cust)
  (Minor)under Uniform Gifts to MinorsAct(State)  Additional abbreviations may be used though not in the above list.  For value received,                      
hereby sell, assign and transfer unto  PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE  (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF
ASSIGNEE)  shares of the capital stock represented by the within Certificate, and
do hereby irrevocably constitute and appoint Attorney to transfer the said shares on the books of the within named
Corporation with full power of substitution in the premises.  Dated


NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME
AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT
ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.  This certificate also evidences and entitles the holder hereof to
certain Rights as set forth in the Rights Agreement between Medarex, Inc.
(the Company) and the Rights Agent thereunder (the Rights Agreement), the
terms of which are hereby incorporated herein by reference and a copy of which
is on file at the principal offices of the Rights Agent. Under certain
circumstances, as set forth in the Rights Agreement, such Rights will be
evidenced by separate certificates and will no longer be evidenced by this
certificate. The Company will mail to the holder of this certificate a copy of
the Rights Agreement, as in effect on the date of mailing, without charge,
promptly after receipt of a written request therefor. Under certain circumstances
set forth in the Rights Agreement, Rights issued to, or held by, any Person who
is, was or becomes an Acquiring Person or any Affiliate or Associate thereof
(as such terms are defined in the Rights Agreement), whether currently held by
or behalf of such Person or by any subsequent holder, may become null and void.