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Exhibit 4.3    
    


[FACE
OF CERTIFICATE]

COMMON STOCK

NUMBER

FC

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

FASTCLICK, INC.

COMMON STOCK

SHARES

SEE REVERSE FOR CERTAIN DEFINITIONS

CUSIP 31188F 10 5

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

THIS CERTIFIES THAT

IS THE RECORD HOLDER OF

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

FASTCLICK, INC.



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:

/S/

CHIEF FINANCIAL OFFICER AND SECRETARY

[SEAL]

/S/

CHIEF EXECUTIVE OFFICER

COUNTERSIGNED AND REGISTERED:

EQUISERVE TRUST COMPANY, N.A.

TRANSFER AGENT AND REGISTRAR

BY:

AUTHORIZED SIGNATURE



[REVERSE
OF CERTIFICATE] 


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: 


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, 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 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

THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME(S) 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. 











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Exhibit 4.3