Exhibit 4.2


 


NUMBER


C-


 


SHARES


 


SEE REVERSE FOR CERTAIN DEFINITIONS


 


CUSIP


 


ALTC ACQUISITION CORP.


 


INCORPORATED UNDER THE LAWS OF THE STATE
OF DELAWARE


 


CLASS A COMMON STOCK


 


This Certifies that

is the owner of

FULLY PAID AND NON-ASSESSABLE SHARES OF THE PAR VALUE OF $0.0001 EACH OF THE CLASS A COMMON STOCK OF


 


ALTC ACQUISITION CORP.


 


(THE “CORPORATION”)


 


transferable on the books of the Corporation in person or by
duly authorized attorney upon surrender of this certificate properly endorsed.


 


The Corporation will be forced to offer
to redeem of all its shares of Class A common stock in connection with an initial business combination or to redeem all of
its shares of Class A common stock if it is unable to complete a business combination by          , 2023 (unless extended pursuant
to the Corporation’s Certificate of Incorporation as in effect at such time), all as more fully described in the Corporation’s
final prospectus dated          , 2021.


 


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


 


Witness the seal of the Corporation and
the facsimile signatures of its duly authorized officers.


 


	 	 	 	 	 
	Secretary	 	[Corporate Seal] Delaware	 	Chief Executive Officer


 






    


     


    

 


ALTC ACQUISITION CORP.


 


The Corporation will furnish without charge
to each stockholder who so requests the powers, designations, preferences and relative, participating, optional or other special
rights of each class of stock or series thereof of the Corporation and the qualifications, limitations, or restrictions of such
preferences and/or rights. This certificate and the shares represented thereby are issued and shall be held subject to all the
provisions of the Certificate of Incorporation and all amendments thereto and resolutions of the Board of Directors providing for
the issue of securities (copies of which may be obtained from the secretary of the Corporation), to all of which the holder of
this certificate by acceptance hereof assents. 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)




  


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(S) OF ASSIGNEE(S))


 


(PLEASE PRINT OR TYPEWRITE NAME(S) AND
ADDRESS(ES), INCLUDING ZIP CODE, OF ASSIGNEE(S))


 


Shares of the capital stock represented
by the within Certificate, and hereby irrevocably constitutes and appoints


 


Attorney to transfer the said stock on the
books of the within named Corporation 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:	 
	 	 
	By	 




 






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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 (OR ANY SUCCESSOR RULE).


 


In each case, as more fully described in
the Corporation’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 Corporation redeems the shares of Class A common stock sold in the Company’s initial public offering
and liquidates because it does not consummate an initial business combination by          , 2023 (or such later date if such period is extended
pursuant to the Company’s Certificate of Incorporation as in effect at such time), (ii) the Corporation redeems the
shares of Class A common stock sold in its initial public offering in connection with a stockholder vote to amend the Corporation’s
amended and restated certificate of incorporation to modify the substance or timing of the Corporation’s obligation to redeem
100% of the Class A common stock if it does not consummate an initial business combination by          , 2023 (or such later date if
such period is extended pursuant to the Company’s Certificate of Incorporation as in effect at such time) or with respect
to any other material provisions relating to stockholders’ rights of pre-initial business combination activity, or (iii) if
the holder(s) seek(s) to redeem for cash his, her or its respective shares of Class A common stock in connection
with a tender offer (or proxy solicitation, solely in the event the Corporation seeks stockholder 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.


 






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