Exhibit 4.2


 


SPECIMEN CLASS A ORDINARY SHARE
CERTIFICATE


 


	NUMBER	SHARES


 


HORIZON ACQUISITION CORPORATION

INCORPORATED UNDER THE LAWS OF THE CAYMAN ISLANDS

CLASS A ORDINARY SHARES


 


SEE REVERSE FOR

CERTAIN DEFINITIONS


 


CUSIP [ ]


 


This Certifies that                                               is
the owner of


 


FULLY PAID AND NON-ASSESSABLE CLASS A
ORDINARY SHARES OF THE PAR VALUE OF US$0.0001 EACH OF HORIZON ACQUISITION CORPORATION (THE “COMPANY”)


 


subject to the Company’s amended
and restated memorandum and articles of association, as the same may be amended from time to time, and transferable on the books
of the Company in person or by duly authorized attorney upon surrender of this certificate properly endorsed.


 


The Company will be forced to redeem
all of its Class A ordinary shares if it is unable to complete a business combination within the period of time set forth
in the Company’s amended and restated memorandum and articles of association, as the same may be amended from time to time,
all as more fully described in the Company’s final prospectus dated [●], 2020.


 


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


 


Witness the facsimile signatures of its
duly authorized officers.


 


	Dated:	 	 
	 	 	 


 


	Chief Executive Officer	Cayman Islands	Chief Financial Officer
	 	 	 
	 	 	 


 




     


     


    

 


HORIZON ACQUISITION CORPORATION


 


The Company will furnish without charge to each shareholder
who so requests 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.
This certificate and the shares represented thereby are issued and shall be held subject to all the provisions of the Company’s
[amended and restated] memorandum and articles of association, as the same may be amended from time to time, and resolutions of
the Board of Directors providing for the issue of Class A ordinary shares (copies of which may be obtained from the secretary
of the Company), 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	 
	 	 	 	 	 	 	 	 
	 	 	 	 	 	(Cust)	 	(Minor)
	 	 	 	 	 	 	 	 
	 	 	 	 	 	 	 	 
	TEN ENT	—	as tenants by the entireties	 	 	under Uniform Gifts to Minors Act
	 	 	 	 	 	 	 	 
	 	 	 	 	 	 	 	 
	 	 	 	 	 	 	(State)	 
	 	 	 	 	 	 	 	 
	JT TEN	—	as joint tenants with right of survivorship and not as tenants in common	 	 	 	 	 


 


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


 




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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 represented by the within Certificate,
and does hereby irrevocably constitute and appoint                                            
Attorney to transfer the said shares on the books of the within named Company with full power of substitution in the premises.


 


	Dated:	 	 	 
	 	 	 	 
	 	 	 	Shareholder
	 	 	 	 
	 	 	 	NOTICE: THE SIGNATURE(S) 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 OR ANY SUCCESSOR RULE).


 


In each case, as more fully described in the Company’s
final prospectus dated [●], 2020, 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 within the period of time set forth in the Company’s amended and restated memorandum and
articles of association, as the same may be amended from time to time, (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 (A) to modify the substance or timing of the Company’s obligation to
allow redemptions in connection with the Company’s initial business combination or to redeem 100% of the Class A ordinary
shares if it does not complete its initial Business Combination within the time period required by the Company’s Amended
and Restated Memorandum and Articles of Association, as amended from time to time, or (B) with respect to any other provision
relating to shareholders’ rights or pre-initial business combination activity, 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.


 



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