Exhibit 4.1


 


	NUMBER	UNITS
	U-	 


 


	SEE REVERSE FOR CERTAIN DEFINITIONS	
	 	CUSIP 349885 202



 


 


FORUM MERGER III CORPORATION 


 


UNITS CONSISTING OF
ONE SHARE OF CLASS A COMMON STOCK AND ONE-FOURTH OF ONE REDEEMABLE 

WARRANT, EACH WHOLE WARRANT ENTITLING THE HOLDER TO PURCHASE
ONE SHARE OF CLASS A COMMON STOCK


 


THIS CERTIFIES THAT                                              is
the owner of                                     Units.


 


Each Unit (“Unit”)
consists of one (1) share of Class A common stock, par value $0.0001 per share (“Common Stock”), of Forum
Merger III Corporation, a Delaware corporation (the “Company”), and one-fourth of one redeemable warrant
(the “Warrant”). Each whole Warrant entitles the holder to purchase one (1) share (subject to adjustment)
of Common Stock for $11.50 per share (subject to adjustment). Only whole Warrants are exercisable. Each whole Warrant will become
exercisable on the later of (i) thirty (30) days after the Company’s completion of a merger, capital stock exchange, asset
acquisition, stock purchase, reorganization or other similar business combination with one or more businesses (each a “Business
Combination”), and (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 “Expiration Date”).
The Common Stock and Warrants comprising the Units represented by this certificate are not transferable separately prior to                                , 2020,
unless Jefferies LLC elects to allow separate trading earlier, subject to the Company’s filing of a Current Report on Form
8-K with the Securities and Exchange Commission containing an audited balance sheet reflecting the Company’s receipt of the
gross proceeds of the Company’s initial public offering and issuing a press release announcing when 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                                       , 2020 (the “Warrant Agreement”), 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 1 State Street, 30th Floor, New York, New York 10004, and are available to any Warrant holder on written request
and without cost.


 


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


 


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 a duly authorized signatory of the Company.


 


	 	 	 
	Authorized Signatory	 	Transfer Agent


 






     

     


    

 


Forum Merger III 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 stock 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 Act
	JT TEN	—	 	as joint tenants with right of survivorship and not as tenants in common	 	 	 	
        _____________________________

        (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)


  


Units represented
by the within certificate, and do hereby irrevocably constitute and appoint 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 UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED (OR ANY SUCCESSOR RULE)).	 


 






    	 	2	 



     


    

 


As more fully described
in, and subject to the terms and conditions described in, the Company’s final prospectus for its initial public offering
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 the Company’s initial public offering only in the event that (i) the Company redeems
the shares of Common Stock sold in the Company’s initial public offering and liquidates because it does not consummate an
initial business combination by the date set forth (the “Last Date”) in the Company’s Amended and Restated Certificate
of Incorporation, as the same may be amended from time to time (the “Charter”), (ii) the Company redeems the shares
of Common Stock sold in its initial public offering properly submitted in connection with a stockholder vote to amend the Charter
to modify the substance or timing of the Company’s obligation to redeem 100% of the Common Stock if it does not consummate
an initial business combination by the Last Date or with respect to any other material provisions relating to stockholders’
rights or pre-initial business combination activity, or (iii) if the holder(s) seek(s) to redeem for cash his, her or its respective
shares of Common Stock in connection with a tender offer (or proxy solicitation, solely in the event the Company 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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