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                                                                     EXHIBIT 4.1

NM

Natus Medical Incorporated

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

THIS CERTIFICATE IS TRANSFERABLE
IN CANTON, MA OR NEW YORK, NY

SEE REVERSE FOR CERTAIN DEFINITIONS
CUSIP 639050 10 3

This Certifies that

is the record holder of

FULLY PAID AND NONASSESSABLE SHARES OF COMMON STOCK, $0.001 PAR VALUE PER SHARE,
OF

Natus Medical Incorporated

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 and registered by
the Transfer Agent and Registrar.
  WITNESS the facsimile seal of the Corporation and the facsimile signatures of
its duly authorized officers.
Dated:

CHAIRMAN

PRESIDENT AND CHIEF EXECUTIVE OFFICER

COUNTERSIGNED AND REGISTERED:
EQUISERVE TRUST COMPANY, N.A.
TRANSFER AGENT
AND REGISTRAR
BY
AUTHORIZED SIGNATURE
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NATUS MEDICAL INCORPORATED
A statement of the rights, preferences, privileges and restrictions granted to
or imposed upon the respective classes or series of shares of stock of the
Corporation, and upon the holders thereof as established by the Certificate of
Incorporation or by any certificate of determination of preferences, and the
number of shares constituting each class or series, and the designations
thereof, may be obtained by the holder hereof upon request and without charge
from the Secretary of the Corporation 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:

  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 Minors
         Act................................................
                               (State)
   UNIF TRF MIN ACT -- ................ Custodian (until age ..............)
                           (Cust)
                       .......................... under Uniform Transfers
                                  (Minor)
                       to Minors Act ......................................
                                                     (State)

     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:
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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.