<PAGE>
EXHIBIT 4.1
--------------- --------------
Number [LOGO] Shares
--------------- --------------
XENOGEN
Discovery in the Living Organism(TM)
<TABLE>
<S> <C> <C>
THIS CERTIFICATE IS TRANSFERABLE INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE SEE REVERSE FOR CERTAIN DEFINITIONS
IN CANTON, MA OR NEW YORK, NY CUSIP 9841OR 10 8
</TABLE>
This Certifies that
is the record holder of
FULLY PAID AND NONASSESSABLE SHARES OF COMMON STOCK, $0.001 PAR VALUE, OF
________________________ _________________________
____________________________ XENOGEN CORPORATION ______________________________
________________________ _________________________
transferable on the books of the Corporation by the holder hereof in person or
by duly authorized attorney upon surrender of this certificate properly
endorsed. This certificate is not valid until countersigned by the Transfer
Agent and registered by the Registrar.
WITNESS the facsimile seal of the Corporation and the facsimile signatures of
its duly authorized officers.
Dated:
/s/ Karen A. Dempsey [SEAL] /s/ Pamela Reilly Contag
-------------------- ------------------------
CORPORATE SECRETARY PRESIDENT AND CO-CHIEF EXECUTIVE OFFICER
/s/ David W. Carter
-------------------------
CHAIRMAN AND CO-CHIEF EXECUTIVE OFFICER
<PAGE>
The Corporation shall furnish without charge to each stockholder who so
requests a statement of the powers, designations, preferences and relative,
participating, optional, or other special rights of each class of stock of the
Corporation or series thereof and the qualifications, limitations or
restrictions of such preferences and/or rights. Such requests shall be made to
the Corporation's Secretary at the principal office of the Corporation.
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:
<TABLE>
<S> <C>
TEN COM -- as tenants in common UNIF GIFT MIN ACT -- ................ Custodian...................
TEN ENT -- as tenants by the entireties (Cust) (Minor)
JT TEN -- as joint tenants with right of under Uniform Gifts to Minors
survivorship and not as tenants Act.........................................
in common (State)
UNIF TAF MIN ACT -- ............Custodian (unit age .............)
(Cust)
................... under Uniform Transfers
(Minor)
to Minors Act................................
(State)
</TABLE>
Additional abbreviations may also be used though not in the above list.
For Value Received, _____________________________________ hereby sell(s),
assign(s) and transfer(s) 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 common stock represented by the within certificate, and do hereby
irrevocably constitute and appoint
____________________________________________________________________ Attorney
to transfer the said stock on the books of the within named Corporation with
full power of substitution in the premises.
Dated _______________________________
X ______________________________
X ______________________________
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.
Signature(s) Guaranteed
By ______________________________
THE SIGNATURE(S) MUST BE GUARANTEED
BY AN ELIGIBLE GUARANTOR INSTITUTION
(BANKS, STOCKBROKERS, SAVINGS AND LOAN
ASSOCIATIONS AND CREDIT UNIONS WITH
MEMBERSHIP IN AN APPROVED SIGNATURE
GUARANTEE MEDALLION PROGRAM), PURSUANT
TO S.E.C. RULE 17Ad-15.
