Exhibit 4.1


 


	 	NUMBER UNITS U-
	SEE REVERSE FOR CERTAIN DEFINITIONS	CUSIP G85094 111
	 	 


STONEBRIDGE ACQUISITION CORPORATION


UNITS CONSISTING OF ONE CLASS A ORDINARY
SHARE AND ONE-HALF OF ONE

WARRANT TO PURCHASE ONE CLASS A ORDINARY SHARE


 


	THIS CERTIFIES THAT	is the owner of	Units.


 


Each Unit (“Unit”)
consists of one (1) Class A ordinary share, of par value $0.0001 per share (“Ordinary Shares”), of StoneBridge
Acquisition Corporation., a Cayman Islands exempted company (the “Company”), and one-half of one (1)
redeemable warrant (the “Warrant”). Each whole Warrant entitles the holder to purchase one Ordinary Share
(subject to adjustment) for $11.50 per share (subject to adjustment). Each Warrant will become exercisable on the later of (i)
thirty (30) days after the Company’s completion of a merger, share exchange, asset acquisition, share purchase, reorganization
or other similar business combination with one or more businesses (each a “Business Combination”), or
(ii) twelve (12) months from the closing of the Company’s initial public offering, and will expire, unless exercised before
5:00 p.m., New York City Time, on the date that is five (5) years after the date on which the Company completes its initial Business
Combination, or earlier upon redemption or liquidation. The Ordinary Shares and Warrants comprising the Units represented by this
certificate are not transferable separately prior to [____], 2021, unless Cantor Fitzgerald & Co. elects to allow separate
trading earlier, subject to the Company’s filing of a Current Report on Form 8-K with the U.S. Securities and Exchange Commission
containing an audited balance sheet reflecting the Company’s receipt of the gross proceeds of its initial public offering
and issuing a press release announcing when such separate trading will begin. No fractional Warrants will be issued upon separation
of the Units. The terms of the Warrants are governed by a Warrant Agreement, dated as of [____], 2021, between the Company and
Continental Stock Transfer & Trust Company, as Warrant Agent, and are subject to the terms and provisions contained therein,
all of which terms and provisions the holder of this certificate consents to by acceptance hereof. Copies of the Warrant Agreement
are on file at the office of the Warrant Agent at One State Street 30th Floor, New York, New York 10004, and are available to any
Warrant holder on written request and without cost.


 


Upon the consummation of the Business Combination,
the Units represented by this certificate will automatically separate into Ordinary Shares and Warrants comprising such Units.


 


This certificate is not valid unless countersigned
by the Transfer Agent and registered by the Registrar.


 


This certificate shall be governed by and
construed in accordance with the internal laws of the State of New York.


 


Witness the facsimile signature of its duly
authorized officers.


 


 


	Chief Executive Officer	 	Secretary


 


	
        CONTINENTAL STOCK TRANSFER

 & TRUST COMPANY

         
	 	 
	Name:	 	 
	Title:	 	 





 






     


     


    

 


StoneBridge Acquisition Corporation


 


The Company will furnish without charge
to each unitholder who so requests, a statement of the powers, designations, preferences and relative, participating, optional
or other special rights of each class of shares or series thereof of the Company 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	 	 
	 	 	 	 	 	 	 	 	 	 	(Cust)	 	 	 	(Minor)
	TEN ENT	 	—	 	as tenants by the entireties	 	 	 	 	 	 	 	 	 	 
	 	 	 	 	 	 	 	 	 	 	Under Uniform Gifts to Minors
	JT TEN	 	—	 	as joint tenants with right of survivorship and not as tenants in common	 	 	 	 	 	Act 
	 	 	 	 	 	 	 	 	 	 	(State)


 


Additional abbreviations may also be used though not in the
above list.


 


For value received, ___________________ hereby sells, assigns
and transfers unto _________________________


 


 


	PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE
	 
	(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)
	 
	________Units represented by the within Certificate, and hereby irrevocably constitutes and appoints ___________
	 
	Attorney to transfer the said Units on the books of the within named Company with full power of substitution in the premises.


 


	Dated:	 	 	 	 
	 	 	 	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:

         
	 	 
	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 (OR ANY SUCCESSOR RULE) UNDER THE SECURITIES ACT OF 1933, AS AMENDED).	 	 





 






     


     


    

 


In each case, as more fully described in the Company’s
final prospectus dated , 2021, the holder(s) of this certificate shall be entitled to receive a pro-rata portion of certain funds
held in the trust account established in connection with its initial public offering only in the event that (i) the Company redeems
the Class A ordinary shares sold in its initial public offering and liquidates because it does not consummate an initial business
combination by , 2023, (ii) the Company redeems the Class A ordinary shares sold in its initial public offering in connection with
a shareholder vote to amend the Company’s amended and restated memorandum and articles of association to modify the substance
and timing of the Company’s obligation to redeem 100% of the Class A ordinary shares if it does not consummate an initial
business combination by , 2023, or (iii) if the holder(s) seek(s) to redeem for cash his, her or its respective Class A ordinary
shares in connection with a tender offer (or proxy solicitation, solely in the event the Company seeks shareholder approval of
the proposed initial business combination) setting forth the details of a proposed initial business combination. In no other circumstances
shall the holder(s) have any right or interest of any kind in or to the trust account.