<PAGE>
Exhibit 4.1
NUMBER SHARES
CID
[CIDRA LOGO]
CIDRA CORPORATION
INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE
SEE REVERSE FOR CERTAIN DEFINITIONS
CUSIP 171770 10 0
THIS CERTIFIES THAT
is the owner of
FULLY PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK, $0.001 PAR VALUE, OF
-----------------------------------CIDRA CORPORATION----------------------------
transferable only 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 and the shares represented hereby are issued under
and subject to the laws of the State of Delaware and to the Certificate of
Incorporation and By-Laws of the Corporation, all as in effect from time to
time. This Certificate is not valid until countersigned and registered by the
Transfer Agent and Registrar.
IN WITNESS WHEREOF, CiDRA Corporation has caused this Certificate to be
executed by the facsimile signatures of its duly authorized officers and sealed
with the facsimile seal of the Corporation.
/s/ Michael Grillo /s/ F. Kevin Didden
Vice President, General Counsel President and Chief
Secretary Executive Officer
[CIDRA CORPORATE SEAL]
COUNTERSIGNED AND REGISTERED:
EQUISERVE TRUST COMPANY, N.A.
TRANSFER AGENT AND REGISTRAR
BY /s/ [illegible]
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AUTHORIZED SIGNATURE
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CIDRA CORPORATION
The Corporation is authorized to issue more than one class and series of
stock. The Corporation will furnish to the holder upon written request without
charge a statement of the powers, designations, preferences and relative,
participating, optional or other special rights of each class of stock or series
thereof and the qualifications, limitations or restrictions of such preferences
and/or rights.
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 UNIF GIFT MIN ACT-.........Custodian.......
TEN ENT - as tenants by the entireties (Cust) (Minor)
JT TEN - as joint tenants with right under Uniform Gifts to Minors
of survivorship and not as Act................
tenants in common (State)
Additional abbreviations may also 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
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(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)
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--------------------------------------------------------------------------shares
of the capital 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______________________
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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:
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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.
