Exhibit 10.3


 


January
9, 2018


 


Nebula
Acquisition Corporation

480 Pacific Avenue, Suite 200

San Francisco, CA 94133


 


Re:
Initial Public Offering


 


Gentlemen:


 


This
letter (this “Letter Agreement”) is being delivered to you in accordance with the Underwriting Agreement
(the “Underwriting Agreement”) to be entered into by and among Nebula Acquisition Corporation, a Delaware
corporation (the “Company”), Deutsche Bank Securities Inc. and Goldman, Sachs & Co., as representatives
(the “Representatives”) of the several underwriters (each, an “Underwriter”
and collectively, the “Underwriters”), relating to an underwritten initial public offering (the “Public
Offering”), of 28,750,000 of the Company’s units (including up to 3,750,000 units that may be purchased to
cover over-allotments, if any) (the “Units”), each comprised of one share of the Company’s Class A
common stock, par value $0.0001 per share (the “Common Stock”), and one-third of one warrant. Each whole
Warrant (each, a “Warrant”) entitles the holder thereof to purchase one share of Common Stock at a price
of $11.50 per share, subject to adjustment. The Units shall be sold in the Public Offering pursuant to a registration statement
on Form S-1 and prospectus (the “Prospectus”) filed by the Company with the Securities and Exchange
Commission (the “Commission”) and the Company shall apply to have the Units listed on the Nasdaq Capital
Market. Certain capitalized terms used herein are defined in paragraph 11 hereof.


 


In
order to induce the Company and the Underwriters to enter into the Underwriting Agreement and to proceed with the Public Offering
and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Nebula Holdings,
LLC (the “Sponsor”) and each of the undersigned individuals, each of whom is a member of the Company’s
board of directors and/or management team (each, an “Insider” and collectively, the “Insiders”),
hereby agrees with the Company as follows:


 


1. 
The Sponsor and each Insider agrees that if the Company seeks stockholder approval of a proposed Business Combination, then in
connection with such proposed Business Combination, it, he or she shall (i) vote any shares of Capital Stock owned by it,
him or her in favor of any proposed Business Combination and (ii) not redeem any shares of Common Stock owned by it, him
or her in connection with such stockholder approval.


 


2. 
The Sponsor and each Insider hereby agrees that in the event that the Company fails to consummate a Business Combination within
24 months from the closing of the Public Offering , or such later period approved by the Company’s stockholders in accordance
with the Company’s amended and restated certificate of incorporation, the Sponsor and each Insider shall take all reasonable
steps to cause the Company to (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably
possible but not more than 10 business days thereafter, subject to lawfully available funds therefor, redeem 100% of the Common
Stock sold as part of the Units in the Public Offering (the “Offering Shares”), at a per-share price,
payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest earned on the funds held
in the Trust Account and not previously released to the Company to pay its franchise and income taxes and up to $500,000 that
may be released to the Company for working capital purposes (less up to $100,000 of interest to pay dissolution expenses), divided
by the number of then outstanding Offering Shares, which redemption will completely extinguish all Public Stockholders’
rights as stockholders (including the right to receive further liquidation distributions, if any), subject to applicable law,
and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the Company’s remaining
stockholders and the Company’s board of directors, dissolve and liquidate, subject in each case to the Company’s obligations
under Delaware law to provide for claims of creditors and other requirements of applicable law. The Sponsor and each Insider agree
not to propose any amendment to the Company’s amended and restated certificate of incorporation that would modify the substance
or timing of the Company’s obligation to redeem 100% of the Offering Shares if the Company does not complete a Business
Combination within 24 months from the closing of the Public Offering, unless the Company provides its Public Stockholders with
the opportunity to redeem their Offering Shares upon approval of any such amendment at a per-share price, payable in cash, equal
to the aggregate amount then on deposit in the Trust Account, including interest (which interest shall be net of amounts released
for payment of taxes and up to $500,000 for working capital released to the Company) divided by the number of then outstanding
Offering Shares.


 






     

    


    

 


The
Sponsor and each Insider acknowledges that it, he or she has no right, title, interest or claim of any kind in or to any monies
held in the Trust Account or any other asset of the Company as a result of any liquidation of the Company with respect to the
Founder Shares held by it, him or her. The Sponsor and each Insider hereby further waives, with respect to any shares of Common
Stock held by it, him or her, if any, any redemption rights it, he or she may have in connection with the consummation of a Business
Combination, including, without limitation, any such rights available in the context of a stockholder vote to approve such Business
Combination or in the context of a tender offer made by the Company to purchase shares of Common Stock (although the Sponsor,
the Insiders and their respective affiliates shall be entitled to redemption and liquidation rights with respect to any Offering
Shares it or they hold if the Company fails to consummate a Business Combination within 24 months from the date of the closing
of the Public Offering).


 


3. 
During the period commencing on the effective date of the Underwriting Agreement and ending 180 days after such date, the Sponsor
and each Insider shall not, without the prior written consent of the Representatives, (i) sell, offer to sell, contract or
agree to sell, hypothecate, pledge, grant any option to purchase or otherwise dispose of or agree to dispose of, directly or indirectly,
or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section 16
of the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder,
with respect to any Units, shares of Capital Stock, Warrants or any securities convertible into, or exercisable, or exchangeable
for, shares of Common Stock owned by it, him or her, (ii) enter into any swap or other arrangement that transfers to another,
in whole or in part, any of the economic consequences of ownership of any Units, shares of Capital Stock, Warrants or any securities
convertible into, or exercisable, or exchangeable for, shares of Common Stock owned by it, him or her, whether any such transaction
is to be settled by delivery of such securities, in cash or otherwise, or (iii) publicly announce any intention to effect
any transaction specified in clause (i) or (ii). Each of the Insiders and the Sponsor acknowledges and agrees that, prior
to the effective date of any release or waiver of the restrictions set forth in this paragraph 3 or paragraph 7 below, the Company
shall announce the impending release or waiver by press release through a major news service at least two business days before
the effective date of the release or waiver. Any release or waiver granted shall only be effective two business days after the
publication date of such press release. The provisions of this paragraph will not apply if (i) the release or waiver is effected
solely to permit a transfer of securities that is not for consideration and (ii) the transferee has agreed in writing to be bound
by the same terms described in this Letter Agreement to the extent and for the duration that such terms remain in effect at the
time of the transfer.


 


4. 
In the event of the liquidation of the Trust Account, the Sponsor (which for purposes of clarification shall not extend to any
other shareholders, members or managers of the Sponsor) agrees to indemnify and hold harmless the Company against any and all
loss, liability, claim, damage and expense whatsoever (including, but not limited to, any and all legal or other expenses reasonably
incurred in investigating, preparing or defending against any litigation, whether pending or threatened, or any claim whatsoever)
to which the Company may become subject as a result of any claim by (i) any third party (other than the Company’s independent
accountants) for services rendered or products sold to the Company or (ii) a prospective target business with which the Company
has entered into a letter of intent, confidentiality or other similar agreement for a Business Combination agreement (a “Target”);
provided, however, that such indemnification of the Company by the Sponsor shall apply only to the extent necessary
to ensure that such claims by a third party for services rendered (other than the Company’s independent public accountants)
or products sold to the Company or a Target do not reduce the amount of funds in the Trust Account to below (i) $10.00 per
share of the Offering Shares or (ii) such lesser amount per share of the Offering Shares held in the Trust Account due to
reductions in the value of the trust assets as of the date of the liquidation of the Trust Account, in each case, net of the amount
of interest earned on the property in the Trust Account which may be withdrawn to pay taxes, and up to $500,000 for working capital
purposes, except as to any claims by a third party (including a Target) who executed a waiver of any and all rights to seek access
to the Trust Account and except as to any claims under the Company’s indemnity of the Underwriters against certain liabilities,
including liabilities under the Securities Act of 1933, as amended. In the event that any such executed waiver is deemed to be
unenforceable against such third party, the Sponsor shall not be responsible to the extent of any liability for such third party
claims. The Sponsor shall have the right to defend against any such claim with counsel of its choice reasonably satisfactory to
the Company if, within 15 days following written receipt of notice of the claim to the Sponsor, the Sponsor notifies the Company
in writing that it shall undertake such defense.


 






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5. 
To the extent that the Underwriters do not exercise their over-allotment option to purchase up to an additional 3,750,000 Units
within 45 days from the date of the Prospectus (and as further described in the Prospectus), the Sponsor agrees to forfeit, at
no cost, a number of Founder Shares in the aggregate equal to the product of 937,500 multiplied by a fraction, (i) the numerator
of which is 3,750,000 minus the number of Units purchased by the Underwriters upon the exercise of their over-allotment option,
and (ii) the denominator of which is 3,750,000. The forfeiture will be adjusted to the extent that the over-allotment option
is not exercised in full by the Underwriters so that the Initial Stockholders will own an aggregate of 20.0% of the Company’s
issued and outstanding shares of Capital Stock after the Public Offering.


 


6. 
(a)  The Sponsor and each Insider who is an officer of the Company hereby agrees not to participate in the formation of,
or become an officer or director of, any other blank check company unless the Company has failed to complete a Business Combination
within 24 months after the closing of the Public Offering. Such restriction does not preclude any position as an officer or director
of another blank check company held on the date hereof. For the avoidance of doubt, the Sponsor and each Insider who is an officer
of the Company are allowed to participate in the formation of, or become an officer or director of, another blank check company
upon the Company entering into a definitive agreement with respect to a Business Combination.


 


(b) 
The Sponsor and each Insider hereby agrees and acknowledges that: (i) the Underwriters and the Company would be irreparably
injured in the event of a breach by such Sponsor or an Insider of its, his or her obligations under paragraphs 1, 2, 3, 4, 5,
6(a), 7(a), 7(b), and 9 of this Letter Agreement (ii) monetary damages may not be an adequate remedy for such breach and
(iii) the non-breaching party shall be entitled to injunctive relief, in addition to any other remedy that such party may
have in law or in equity, in the event of such breach.


 


7. 
(a)  The Sponsor and each Insider agrees that it or he shall not Transfer any Founder Shares (or shares of Common Stock issuable
upon conversion thereof) until the earlier of (A) one year after the completion of the Company’s initial Business Combination
or (B) subsequent to the Business Combination, (x) if the last sale price of the Common Stock equals or exceeds $12.00
per share (as adjusted for stock splits, stock dividends, reorganizations, recapitalizations and the like) for any 20 trading
days within any 30-trading day period commencing at least 150 days after the Company’s initial Business Combination or (y) the
date on which the Company completes a liquidation, merger, capital stock exchange, reorganization or other similar transaction
that results in all of the Company’s stockholders having the right to exchange their shares of Common Stock for cash, securities
or other property (the “Founder Shares Lock-up Period”).


 


(b) 
The Sponsor and each Insider agrees that it, he or she shall not Transfer any Private Placement Warrants (or shares of Common
Stock issued or issuable upon the exercise of the Private Placement Warrants) until 30 days after the completion of a Business
Combination (the “Private Placement Warrants Lock-up Period”, together with the Founder Shares Lock-up
Period, the “Lock-up Periods”).


 


(c) 
Notwithstanding the provisions set forth in paragraphs 7(a) and (b), Transfers of the Founder Shares, Private Placement Warrants
and shares of Common Stock issued or issuable upon the exercise or conversion of the Private Placement Warrants or the Founder
Shares and that are held by the Sponsor, any Insider or any of their permitted transferees (that have complied with this paragraph
7(c)), are permitted (a) to the Company’s officers or directors, any affiliates or family members of any of the Company’s
officers or directors, any members of the Sponsor, or any affiliates of the Sponsor; (b) in the case of an individual, by
gift to a member of the individual’s immediate family, to a trust, the beneficiary of which is a member of the individual’s
immediate family or an affiliate of such person, or to a charitable organization; (c) in the case of an individual, transfers
by virtue of laws of descent and distribution upon death of the individual; (d) in the case of an individual, transfers pursuant
to a qualified domestic relations order; (e) transfers by private sales or transfers made in connection with the consummation
of a Business Combination at prices no greater than the price at which the securities were originally purchased; (f) transfers
in the event of the Company’s liquidation prior to the completion of an initial Business Combination; (g) transfers
by virtue of the laws of the State of Delaware or the Sponsor’s limited liability company agreement upon dissolution of
the Sponsor; and (h) in the event of the Company’s liquidation, merger, capital stock exchange, reorganization or other
similar transaction which results in all of the Company’s stockholders having the right to exchange their shares of Common
Stock for cash, securities or other property subsequent to the completion of the Company’s initial Business Combination;
provided, however, that in the case of clauses (a) through (h), these permitted transferees must enter into a written agreement
agreeing to be bound by the restrictions herein.


 






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8. 
The Sponsor and each Insider represents and warrants that it, he or she has never been suspended or expelled from membership in
any securities or commodities exchange or association or had a securities or commodities license or registration denied, suspended
or revoked. Each Insider’s biographical information furnished to the Company (including any such information included in
the Prospectus) is true and accurate in all respects and does not omit any material information with respect to the Insider’s
background. The Sponsor and each Insider’s questionnaire furnished to the Company is true and accurate in all respects.
The Sponsor and each Insider represents and warrants that: it, he or she is not subject to or a respondent in any legal action
for, any injunction, cease-and-desist order or order or stipulation to desist or refrain from any act or practice relating to
the offering of securities in any jurisdiction; it, he or she has never been convicted of, or pleaded guilty to, any crime (i) involving
fraud, (ii) relating to any financial transaction or handling of funds of another person, or (iii) pertaining to any
dealings in any securities and it, he or she is not currently a defendant in any such criminal proceeding.


 


9. 
(a) Except as disclosed in the Prospectus, neither the Sponsor nor any Insider nor any affiliate of the Sponsor or any Insider,
nor any director or officer of the Company, shall receive from the Company any finder’s fee, reimbursement, consulting fee,
monies in respect of any repayment of a loan or other compensation prior to, or in connection with any services rendered in order
to effectuate the consummation of the Company’s initial Business Combination (regardless of the type of transaction that
it is), other than the following, none of which will be made from the proceeds held in the Trust Account prior to the completion
of the initial Business Combination: repayment of a loan and advances up to an aggregate of $300,000 made to the Company by the
Sponsor; reimbursement for any out-of-pocket expenses related to identifying, investigating and consummating an initial Business
Combination; and repayment of loans, if any, and on such terms as to be determined by the Company from time to time, made by the
Sponsor or any of the Company’s officers or directors to finance transaction costs in connection with an intended initial
Business Combination, provided, that, if the Company does not consummate an initial Business Combination, a portion of the working
capital held outside the Trust Account may be used by the Company to repay such loaned amounts so long as no proceeds from the
Trust Account are used for such repayment. Up to $1,500,000 of such loans may be convertible into warrants at a price of $1.50
per warrant at the option of the lender. Such warrants would be identical to the Private Placement Warrants, including as to exercise
price, exercisability and exercise period.


 


(b)
Commencing on the effective date of the Prospectus for the Public Offering and continuing until the earlier of (i) the consummation
by the Company of a Business Combination or (ii) the Company’s liquidation as described in the Prospectus, True Wind Capital,
L.P. shall make available to the Company, at no charge, certain office space and administrative and support services as may be
required by the Company from time to time, situated at Four Embarcadero Center, Suite 2350, San Francisco, CA 94111 (or any successor
locations).


 


10. 
The Sponsor and each Insider has full right and power, without violating any agreement to which it is bound (including, without
limitation, any non-competition or non-solicitation agreement with any employer or former employer), to enter into this Letter
Agreement and, as applicable, to serve as an officer and/or a director on the board of directors of the Company and hereby consents
to being named in the Prospectus as an officer and/or a director of the Company.


 


11. 
As used herein, (i) “Business Combination” shall mean a merger, capital stock exchange, asset acquisition,
stock purchase, reorganization or similar business combination, involving the Company and one or more businesses; (ii) “Capital
Stock” shall mean, collectively, the Common Stock and the Founder Shares; (iii) “Founder Shares”
shall mean the 7,187,500 shares of the Company’s Class B common stock, par value $0.0001 per share, (or 6,250,000 shares
if the over-allotment option is not exercised by the Underwriters) initially held by the Sponsor; (iv) “Initial
Stockholders” shall mean the Sponsor and any other holder of Founder Shares immediately prior to the Public Offering;
(v) “Private Placement Warrants” shall mean the warrants to purchase up to 4,666,667 shares of
Common Stock of the Company (or 5,166,667 shares of Common Stock if the over-allotment option is exercised in full) that the Sponsor
has agreed to purchase for an aggregate purchase price of $7,000,000 in the aggregate (or $7,750,000 if the over-allotment option
is exercised in full), or $1.50 per warrant, in a private placement that shall occur simultaneously with the consummation of the
Public Offering; (vi) “Public Stockholders” shall mean the holders of securities issued in the
Public Offering; (vii) “Trust Account” shall mean the trust fund into which a portion of the net
proceeds of the Public Offering and the sale of the Private Placement Warrants shall be deposited; (viii) “Transfer”
shall mean the (a) sale or assignment of, offer to sell, contract or agreement to sell, hypothecate, pledge, grant of any
option to purchase or otherwise dispose of or agreement to dispose of, directly or indirectly, or establishment or increase of
a put equivalent position or liquidation with respect to or decrease of a call equivalent position within the meaning of Section 16
of the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder
with respect to, any security, (b) entry into any swap or other arrangement that transfers to another, in whole or in part,
any of the economic consequences of ownership of any security, whether any such transaction is to be settled by delivery of such
securities, in cash or otherwise, or (c) public announcement of any intention to effect any transaction specified in clause
(a) or (b).


 






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12.
This Letter Agreement constitutes the entire agreement and understanding of the parties hereto in respect of the subject matter
hereof and supersedes all prior understandings, agreements, or representations by or among the parties hereto, written or oral,
to the extent they relate in any way to the subject matter hereof or the transactions contemplated hereby. This Letter Agreement
may not be changed, amended, modified or waived (other than to correct a typographical error) as to any particular provision,
except by a written instrument executed by all parties hereto.


 


13.
No party hereto may assign either this Letter Agreement or any of its rights, interests, or obligations hereunder without the
prior written consent of the other parties. Any purported assignment in violation of this paragraph shall be void and ineffectual
and shall not operate to transfer or assign any interest or title to the purported assignee. This Letter Agreement shall be binding
on the Sponsor and each Insider and their respective successors, heirs and assigns and permitted transferees.


 


14.
Nothing in this Letter Agreement shall be construed to confer upon, or give to, any person or corporation other than the parties
hereto any right, remedy or claim under or by reason of this Letter Agreement or of any covenant, condition, stipulation, promise
or agreement hereof. All covenants, conditions, stipulations, promises and agreements contained in this Letter Agreement shall
be for the sole and exclusive benefit of the parties hereto and their successors, heirs, personal representatives and assigns
and permitted transferees.


 


15.
This Letter Agreement may be executed in any number of original or facsimile counterparts and each of such counterparts shall
for all purposes be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument.


 


16.
This Letter Agreement shall be deemed severable, and the invalidity or unenforceability of any term or provision hereof shall
not affect the validity or enforceability of this Letter Agreement or of any other term or provision hereof. Furthermore, in lieu
of any such invalid or unenforceable term or provision, the parties hereto intend that there shall be added as a part of this
Letter Agreement a provision as similar in terms to such invalid or unenforceable provision as may be possible and be valid and
enforceable.


 


17.
This Letter Agreement shall be governed by and construed and enforced in accordance with the laws of the State of New York, without
giving effect to conflicts of law principles that would result in the application of the substantive laws of another jurisdiction.
The parties hereto (i) all agree that any action, proceeding, claim or dispute arising out of, or relating in any way to, this
Letter Agreement shall be brought and enforced in the courts of New York City, in the State of New York, and irrevocably submit
to such jurisdiction and venue, which jurisdiction and venue shall be exclusive and (ii) waive any objection to such exclusive
jurisdiction and venue or that such courts represent an inconvenient forum.


 


18.
Any notice, consent or request to be given in connection with any of the terms or provisions of this Letter Agreement shall be
in writing and shall be sent by express mail or similar private courier service, by certified mail (return receipt requested),
by hand delivery or facsimile transmission.


 


19.
This Letter Agreement shall terminate on the earlier of (i) the expiration of the Lock-up Periods or (ii) the liquidation of the
Company; provided, however, that this Letter Agreement shall earlier terminate in the event that the Public Offering is not consummated
and closed by June 30, 2018; provided further that paragraph 4 of this Letter Agreement shall survive such liquidation.


 


[Signature
Page Follows]


 






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	 	Sincerely,
	 	 
	 	NEBULA HOLDINGS, LLC
	 	 
	 	By: 	/s/
Adam H. Clammer
	 	Name: 	Adam H. Clammer
	 	Title:   
	Managing
Member of


True Wind Capital GP, LLC,


General Partner of


True Wind Capital L.P.,


As Sole Managing Member of


Nebula Holdings, LLC

	 	 
	 	By: 	/s/ Adam H. Clammer
	 	Name: 	Adam H. Clammer
	 	 
	 	By: 	/s/ James H. Greene, Jr.
	 	Name: 	James H.
Greene, Jr.
	 	 
	 	By: 	/s/ Rufina Adams
	 	Name: 	Rufina Adams




 


	 	By: 	/s/ David Kerko
	 	Name:	David Kerko
	 	 	 
	 	By: 	/s/ Frank Kern  
	 	Name: 	Frank Kern 
	 	 	 
	 	By: 	/s/ James C. Hale  
	 	Name: 	James  C. Hale  
	 	 	 
	 	By: 	/s/ Ronald Lamb  
	 	Name: 	Ronald Lamb
 




 


FOR
PURPOSES OF SECTION 9(b) ONLY:


 


TRUE
WIND CAPITAL, L.P.


 


	By:
    	/s/
    Adam H. Clammer	 
	Name: 	Adam H. Clammer	 
	Title: 
	Managing
Member of


True Wind Capital GP, LLC,


General Partner of


True Wind Capital L.P.
	 


 


[Signature
Page to Letter Agreement]