Exhibit 10.1


 


February 27, 2019


 


Tortoise Acquisition Corp.

452 Fifth Avenue, 14th Floor

New York, NY 10018


 


Re: Initial Public Offering


 


Ladies and Gentlemen:


 


This letter (this “Letter
Agreement”) is being delivered to you in accordance with the Underwriting Agreement (the “Underwriting
Agreement”) entered into by and among Tortoise Acquisition Corp., a Delaware corporation (the “Company”),
and Barclays Capital Inc., Goldman Sachs & Co. LLC and UBS Securities LLC, as representatives (the “Representatives”)
of the several underwriters (the “Underwriters”), relating to an underwritten initial public offering
(the “Public Offering”), of 25,875,000 of the Company’s units (including up to 3,375,000 units
which 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 “Class A Common Stock”), and
one-half of one redeemable warrant (each whole warrant, a “Warrant”). Each Warrant entitles the holder
thereof to purchase one share of the Class A Common Stock at a price of $11.50 per share, subject to adjustment. The Units shall
be sold in the Public Offering pursuant to the registration statement on Form S-1 No. 333-229537 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 New York Stock Exchange. 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, Tortoise Sponsor LLC, a Delaware
limited liability company (the “Sponsor”), Atlas Point Energy Infrastructure Fund, LLC, a Delaware limited
liability company (“Atlas Point Fund”), Tortoise Borrower LLC, a Delaware limited liability company (“Tortoise
Borrower”) 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 agree with the Company as follows:


 


1. The Sponsor, Atlas
Point Fund and each Insider agree 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 vote all Founder Shares and any shares acquired by it, him or her
in the Public Offering or the secondary public market in favor of such proposed Business Combination.


 


2. The Sponsor and
each Insider hereby agree 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 Class A 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 not previously released to the Company to pay
its franchise and income taxes (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 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 the Insiders agree to not propose any amendment to the Company’s
amended and restated certificate of incorporation that would affect 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 earned on the funds held in the Trust Account and not previously released to the Company to pay its
franchise and income taxes, divided by the number of then outstanding Offering Shares.


 






     


     


    

 


The Sponsor, Atlas
Point Fund 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. The Sponsor, Atlas Point Fund and each Insider hereby further waives, with respect to any shares of the Common Stock held
by it, him or her, 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 the Common Stock and in connection with a stockholder
vote to amend the Company’s amended and restated certificate of incorporation in a manner that would affect the substance
or timing of the Company’s obligation to redeem 100% of the Company’s public shares if the Company has not consummated
a Business Combination within 24 months from the closing of the Public Offering (although the Sponsor, Atlas Point Fund, the Insiders
and their respective affiliates shall be entitled to redemption and liquidation rights with respect to any shares of the Common
Stock (other than the Founder 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 or such later date as may be specified in an amendment to the Company’s
amended and restated certificate of incorporation).


 


3. During the period
commencing on the effective date of the Underwriting Agreement and ending 180 days after such date, the undersigned shall not,
without the prior written consent of Barclays Capital Inc. and Goldman Sachs & Co. LLC, (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,
any Units, shares of Class A Common Stock, shares of the Company’s Class B common stock, par value $0.0001 per share (the
“Class B Common Stock” and, together with the Class A Common Stock, the “Common Stock”),
Warrants or any securities convertible into, or exercisable, or exchangeable for, shares of Common Stock owned by him, her or it;
provided, however, that the foregoing shall not apply to transfers to the Sponsor by Tortoise Borrower, Atlas Point Fund
or the Insiders, (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 Common Stock, Founder Shares, Warrants or any securities convertible into, or
exercisable, or exchangeable for, shares of Class A Common Stock owned by him, her or it, 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). If the undersigned is an officer or director of the Company, the undersigned further agrees that
the forgoing restrictions shall be equally applicable to any issuer-directed Units that the undersigned may purchase in the Public
Offering. Each of the Insiders, Tortoise Borrower, Atlas Point Fund 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 (A) the release or waiver is effected
solely to permit a transfer of securities that is not for consideration and (B) 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 officer, member
or manager 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 public 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 or 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 the lesser of (A) $10.00 per share
of the Offering Shares and (B) the actual 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 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, less franchise
and income taxes payable, except as to any claims by a third party or Target that executed an agreement waiving claims against
and all rights to seek access to the Trust Account whether or not such agreement is enforceable. In the event that any such executed
waiver is deemed to be unenforceable against such third party, the Sponsor shall not be responsible for any liability as a result
of any such third party claims. Notwithstanding any of the foregoing, such indemnification of the Company by the Sponsor shall
not apply as to any claims under the Company’s obligation to indemnify the Underwriters against certain liabilities, including
liabilities under the Securities Act of 1933, as amended (the “Securities Act”). 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 an additional 3,375,000 Units (as described in the Prospectus),
the Sponsor agrees, upon the expiration or waiver of such option, to forfeit, for cancellation at no cost, a number of Founder
Shares equal to 843,750 multiplied by a fraction, (i) the numerator of which is 3,375,000 minus the number of Units purchased by
the Underwriters upon the exercise of their over-allotment option, and (ii) the denominator of which is 3,375,000. The forfeiture
will be adjusted to the extent that the over-allotment option is not exercised in full by the Underwriters so that the Founder
Shares will represent 20.0% of the Company’s issued and outstanding shares of Common Stock after the Public Offering. The
Sponsor further agrees that to the extent that (a) the size of the Public Offering is increased or decreased and (b) the Sponsor
has either purchased or sold shares of Common Stock or an adjustment to the number of Founder Shares has been effected by way of
a stock split, stock dividend, reverse stock split, contribution back to capital or otherwise, in each case in connection with
such increase or decrease in the size of the Public Offering, then (A) the references to 3,375,000 in the numerator and denominator
of the formula in the first sentence of this paragraph shall be changed to a number equal to 15.0% of the number of shares of Class
A Common Stock included in the Units issued in the Public Offering and (B) the reference to 843,750 in the formula set forth in
the first sentence of this paragraph shall be adjusted to such number of Founder Shares that the Sponsor would have to collectively
return to the Company in order for all holders of Founder Shares to hold an aggregate of 20.0% of the Company’s issued and
outstanding shares of Common Stock after the Public Offering.


 


6. (a)  The Sponsor
and each Insider hereby agree not to participate in the formation of, or become an officer or director of, any other blank check
company until the Company has entered into a definitive agreement with respect to a Business Combination or the Company has failed
to complete a Business Combination within 24 months after the closing of the Public Offering.


 


(b) Each of the Sponsor,
Tortoise Borrower, Atlas Point Fund and each Insider hereby agrees and acknowledges that: (i) each of the Underwriters and the
Company would be irreparably injured in the event of a breach by such Sponsor or Insider of his, her or its obligations under paragraphs 1,
2, 3, 4, 5, 6(a), 7(a), 7(b), 7(d) and 9, Tortoise Borrower of its obligations under paragraphs 3, 7(b) and 7(d) or Atlas Point
Fund of its obligations under paragraphs 1, 2, 3 and 7(a) 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)  Subject
to the exceptions set forth herein, the Sponsor, Atlas Point Fund and each Insider agree not to transfer, assign or sell any Founder
Shares held by it, him or her until the earlier of (i) one year after the date of the consummation of a Business Combination and
(ii) the earlier to occur of, subsequent to a Business Combination, (A) the first date on which the last reported 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 consummation of a
Business Combination and (B) the date on which the Company consummates a subsequent liquidation, merger, stock exchange 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 (the “Lock-up”).


 






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(b) Subject to the exceptions
set forth herein, Tortoise Borrower and each Insider agree not to transfer, assign or sell any Private Placement Warrants or Class
A Common Stock underlying such warrants held by it, him or her, until 30 days after the completion of a Business Combination.


 


(c) Notwithstanding the
provisions set forth in paragraphs 7(a) and (b), transfers of the Founder Shares, Private Placement Warrants and shares of
Class A Common Stock issued or issuable upon the exercise or conversion of the Private Placement Warrants or the Founder Shares
and that are held by Tortoise Borrower, the Sponsor, Atlas Point Fund, any Insider or any of their permitted transferees, as applicable,
(that have complied with any applicable requirements of this paragraph 7(c)) are permitted (i) in the case of Tortoise Borrower,
the Sponsor, any Insider or any of their permitted transferees, to the Company’s officers or directors, any affiliates or
family members of any of the Company’s officers or directors, the Sponsor, any members of the Sponsor or their affiliates,
any affiliates of the Sponsor, Tortoise Borrower, any members of Tortoise Borrower or their affiliates or any affiliates of Tortoise
Borrower; (ii) in the case of Atlas Point Fund or any of its permitted transferees, to the Company, Tortoise Borrower, the Sponsor
or any affiliates of Atlas Point Fund; (iii) in the case of an individual, by gift to members of the individual’s immediate
family or to a trust, the beneficiary of which is a member of one of the individual’s immediate family, an affiliate of such
person or to a charitable organization; (iv) in the case of an individual, by virtue of laws of descent and distribution upon death
of the individual; (v) in the case of an individual, pursuant to a qualified domestic relations order; (vi) by virtue of the laws
of the state of Delaware, the Sponsor’s operating agreement upon dissolution of the Sponsor, Tortoise Borrower’s operating
agreement upon dissolution of Tortoise Borrower or Atlas Point Fund’s operating agreement upon dissolution of Atlas Point
Fund; (vii) 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; (viii) in the event of the Company’s liquidation prior
to the completion of a Business Combination; or (ix) in the event of completion of a liquidation, merger, stock exchange 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 a Business Combination; provided, however,
that in the case of clauses (i) through (vii), these permitted transferees must enter into a written agreement agreeing to be bound
by these transfer restrictions.


 


(d) The Sponsor, Tortoise
Borrower and the Insiders acknowledge and agree that if, in order to consummate any Business Combination, the holders of Founder
Shares (other than Atlas Point Fund) or Private Placement Warrants are required to contribute back to the capital of the Company
a portion of any such securities to be cancelled by the Company or transfer any such securities to third parties, the Sponsor,
Tortoise Borrower and the Insiders will contribute back to the capital of the Company or transfer to such third parties, at no
cost, a proportionate number of Founder Shares or Private Placement Warrants, as applicable, pro rata with the other holders of
Founder Shares (other than Atlas Point Fund) or Private Placement Warrants, as applicable.


 


8. Each Insider’s
biographical information furnished to the Company and the Representatives that is included in the Prospectus is true and accurate
in all respects and does not omit any material information with respect to such Insider’s background and contains all of
the information required to be disclosed pursuant to Item 401 of Regulation S-K, promulgated under the Securities Act. Each Insider’s
questionnaire furnished to the Company and the Representatives including any such information that is included in the Prospectus
is true and accurate in all respects. Each Insider represents and warrants that: such Insider 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; such Insider 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 such Insider is not currently a defendant in any such criminal proceeding; and none of the
Sponsor, Atlas Point Fund or any such Insider has ever 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.


 






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9. Except as disclosed
in the Prospectus, none of the Sponsor, Tortoise Borrower, Atlas Point Fund, any affiliate of the Sponsor, Tortoise Borrower or
Atlas Point Fund, or any director or officer of the Company, shall receive 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). However, such persons may receive the following payments, 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 of up to $300,000 made to the Company
by the Sponsor, pursuant to a Promissory Note dated November 7, 2018; payment of an aggregate of $10,000 per month, to the Sponsor,
for office space, utilities, secretarial support and administrative services, pursuant to an Administrative Services Agreement,
dated February 27, 2019; reimbursement for any reasonable out-of-pocket expenses related to identifying, investigating, negotiating
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 an affiliate of the Sponsor or certain of the Company’s officers and 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 $1.00 per warrant at the option of the lender. Such warrants shall
be identical to the Private Placement Warrants, including as to exercise price, exercisability and exercise period.


 


10. The Sponsor, Tortoise
Borrower, Atlas Point Fund and each Insider has full right and power, without violating any agreement to which it, he or she 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 a director on the board of directors of the Company and each
Insider hereby consents to being named in the Prospectus as an officer and/or director of the Company, as applicable.


 


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) “Founder Shares”
shall mean the shares of the Class B Common Stock held by the Sponsor, Atlas Point Fund, the Company’s independent directors
and any other holder prior to the consummation of the Public Offering; (iii) “Private Placement Warrants”
shall mean the warrants to purchase 6,500,000 shares of Class A Common Stock (or 7,175,000 shares of Class A Common Stock if the
Underwriters’ over-allotment option in connection with the Public Offering is exercised in full), that Tortoise Borrower
has agreed to purchase for an aggregate purchase price of approximately $6,500,000 (or approximately $7,175,000 if the Underwriters’
over-allotment option in connection with the Public Offering is exercised in full), or $1.00 per warrant, in a private placement
that shall occur simultaneously with the consummation of the Public Offering; (iv) “Public Stockholders”
shall mean the holders of securities issued in the Public Offering; (v) “Trust Account” shall mean the
trust fund into which a portion of the net proceeds of the Public Offering shall be deposited; and (vi) “Forward Purchase
Agreement” shall mean that certain Amended and Restated Forward Purchase Agreement, dated as of February 6, 2019,
among the Company, the Sponsor and Atlas Point Fund.


 


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. Each of the parties hereto hereby acknowledges and agrees that each of Barclays Capital Inc. and
Goldman Sachs & Co. LLC, on behalf of the Underwriters, is a third party beneficiary of this Agreement.


 


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, Tortoise
Borrower, Atlas Point Fund, each Insider and each of their respective successors, heirs and assigns and permitted transferees.


 


14. 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 the State of New York located in the City and County of New York, Borough of Manhattan,
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.


 






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15. 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.


 


16. This Letter Agreement
shall terminate on the earlier of (i) the expiration of the Lock-up 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, 2019, provided further that paragraph 4 of this Letter Agreement shall survive such liquidation.


 


[Signature Page Follows]


 






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	 	Sincerely,
	 	 
	 	TORTOISE SPONSOR LLC
	 	 	 
	 	By:	/s/ Connie Savage
	 	Name:	Connie Savage
	 	Title:	Chief Financial Officer, Secretary and Treasurer


 


	 	/s/ Vincent T. Cubbage
	 	Vincent T. Cubbage
	 	 
	 	/s/ Stephen Pang
	 	Stephen Pang
	 	 
	 	/s/ Andrew J. Orekar
	 	Andrew J. Orekar
	 	 
	 	/s/ Frank M. Semple
	 	Frank M. Semple
	 	 
	 	/s/ Sidney L. Tassin
	 	Sidney L. Tassin
	 	 
	 	/s/ Connie Savage
	 	Connie Savage
	 	 
	 	/s/ Steven C. Schnitzer
	 	Steven C. Schnitzer
	 	 
	 	/s/ Darrell Brock, Jr.
	 	Darrell Brock, Jr.


 


	 	TORTOISE BORROWER LLC
	 	 
	 	By:	/s/ Connie Savage
	 	Name:	Connie Savage
	 	Title:	Officer
	 	 	 
	 	ATLAS POINT ENERGY INFRASTRUCTURE FUND, LLC
	 	 
	 	By:	/s/ Adam Karpf
	 	Name:	Adam Karpf
	 	Title:	Managing Director and Portfolio Manager


 


	Acknowledged and Agreed:	 
	 	 
	TORTOISE ACQUISITION CORP.	 
	 	 	 
	By:	/s/ Vincent T. Cubbage	 
	Name:	Vincent T. Cubbage	 
	Title:	President and Chief Executive Officer	 


 


[Signature Page to Letter Agreement]