Exhibit 4.1


 


NUMBER
UNITS

U-


 


SEE REVERSE FOR CERTAIN DEFINITIONS


 


CUSIP
629076 209


 


NEBULA ACQUISITION
CORPORATION


 


UNITS CONSISTING
OF ONE SHARE OF CLASS A COMMON STOCK AND ONE-THIRD OF ONE

WARRANT 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 Nebula Acquisition Corporation, a Delaware corporation (the “Company”), and one-third (1/3) of one
warrant (each whole warrant, a “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).  Each 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”), 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 “Expiration
Date”).  The Common Stock and Warrants comprising the Units represented by this certificate are not transferable
separately prior to              , 2018, unless Deutsche
Bank Securities Inc. and Goldman Sachs & Co. LLC elect to allow earlier separate trading, 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 offering and issuing a press release announcing when separate trading
will begin.  The terms of the Warrants are governed by a Warrant Agreement, dated as of               ,
2018, between the Company and American Stock Transfer & Trust Company, LLC, 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 6201 15th Avenue, Brooklyn, New York 11219, 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 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 its duly authorized officers.


 


	 	 	 
	Co-Chief Executive Officer	 	Co-Chief Executive Officer


 




    	 	 	 



     


    

 


Nebula 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 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	 
	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 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	 


 






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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                    ,
2018, 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 Class A common stock sold in its initial public offering and liquidates because it does not consummate
an initial business combination by                       ,
2020, (ii) the Company redeems the shares of Class A common stock sold in its initial public offering in connection with
a stockholder vote to amend the Company’s amended and restated certificate of incorporation to modify the substance or timing
of the Company’s obligation to redeem 100% of the Class A common stock if it does not consummate an initial business
combination by                        ,
2020, 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 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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