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Exhibit 4.3

NUMBER ARAY001				SHARES
	INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE		CUSIP 004397 10 5 SEE REVERSE FOR CERTAIN DEFINITIONS
	ACCURAY INCORPORATED
	THIS CERTIFIES THAT
	is the record holder of
	FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK, 0.001 PAR VALUE PER SHARE, OF ACCURAY INCORPORATED
	transferable on the books of the Corporation 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.
[SEAL]	WITNESS the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers.
	Dated:
		COUNTERSIGNED AND REGISTERED:
		MELLON CAPITAL
		TRANSFER AGENT AND REGISTRAR
		By
		AUTHORIZED SIGNATURE
	/s/ ROBERT E. MCNAMARA	/s/ EUAN S. THOMSON
	SECRETARY	PRESIDENT AND CHIEF EXECUTIVE OFFICER

ACCURAY INCORPORATED

        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 of survivorship and not as tenants in common			under Uniform Gifts to Minors Act      (State)
			UNIF TRF MIN ACT	—		Custodian (until age       )
					(Cust)		(Minor)
					under Uniform Transfers 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(es) 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(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.
SIGNATURES 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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ACCURAY INCORPORATED