As filed with the U.S. Securities and Exchange Commission on November 1, 2017

Registration No. 333-220584

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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AMENDMENT NO. 3 to
FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

__________________

Sentinel Energy Services Inc.

(Exact Name of Registrant as Specified in its Charter)

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1000 Louisiana Street, Suite 3850
Houston, Texas, 77002
(281) 407-0686

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of registrant’s principal executive offices)

Kent Jamison
General Counsel and Secretary
1000 Louisiana Street, Suite 3850
Houston, Texas, 77002
(281) 407-0686

(Name, address, including zip code, and telephone number, including area code, of agent for service)

__________________

Copies to:

__________________

Approximate date of commencement of proposed sale to the public:
As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided to Section 7(a)(2)(B) of the Securities Act. x

CALCULATION OF REGISTRATION FEE

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(1)      Estimated solely for the purpose of calculating the registration fee.

(2)      Includes 4,500,000 units, consisting of 4,500,000 Class A ordinary shares and 1,500,000 warrants, which may be issued upon exercise of a 45-day option granted to the underwriters to cover over-allotments, if any.

(3)      Pursuant to Rule 416(a), there are also being registered an indeterminable number of additional securities as may be issued to prevent dilution resulting from share splits, share dividends or similar transactions.

(4)      No fee pursuant to Rule 457(g).

EXPLANATORY NOTE

Sentinel Energy Services Inc. is filing this Amendment No. 3 to the Registration Statement on Form S-1 (File No. 333-220584) solely for the purpose of filing with the U.S. Securities and Exchange Commission certain exhibits to the Registration Statement.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 13. Other Expenses of Issuance and Distribution.

The estimated expenses payable by us in connection with the offering described in this registration statement (other than the underwriting discounts and commissions) will be as follows:

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(1)      This amount represents the approximate amount of annual director and officer liability insurance premiums the registrant anticipates paying following the completion of its initial public offering and until it completes a business combination.

(2)      This amount represents additional expenses that may be incurred by the Company in connection with the offering over and above those specifically listed above, including distribution and mailing costs.

Item 14. Indemnification of Directors and Officers.

Cayman Islands law does not limit the extent to which a company’s memorandum and articles of association may provide for indemnification of officers and directors, except to the extent any such provision may be held by the Cayman Islands courts to be contrary to public policy, such as to provide indemnification against willful default, willful neglect, civil fraud or the consequences of committing a crime. Our amended and restated memorandum and articles of association provides that all of our directors, officers, employees and agents shall be entitled to be indemnified by us to the fullest extent permitted by law including for any liability incurred in their capacities as such, except through their own actual fraud, willful default or willful neglect. We may purchase a policy of directors’ and officers’ liability insurance that insures our officers and directors against the cost of defense, settlement or payment of a judgment in some circumstances and insures us against our obligations to indemnify our officers and directors. Our officers and directors have agreed to waive any right, title, interest or claim of any kind in or to any monies in the trust account, and have agreed to waive any right, title, interest or claim of any kind they may have in the future as a result of, or arising out of, any services provided to us and will not seek recourse against the trust account for any reason whatsoever. Accordingly, any indemnification provided will only be able to be satisfied by us if (i) we have sufficient funds outside of the trust account or (ii) we consummate an initial business combination.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to our directors, officers, and controlling persons pursuant to the foregoing provisions, or otherwise, we have been advised that, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment of expenses incurred or paid by a director, officer or controlling person in a successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, we will, unless in the opinion of our counsel the matter has been settled by controlling precedent, submit to the court of appropriate jurisdiction the question whether such indemnification by us is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

Our amended and restated memorandum and articles of association will provide for indemnification of our officers and directors to the maximum extent permitted by law, including for any liability incurred in their capacities as such, except through their own actual fraud, willful default or willful neglect. We may purchase a policy of

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directors’ and officers’ liability insurance that insures our officers and directors against the cost of defense, settlement or payment of a judgment in some circumstances and insures us against our obligations to indemnify our officers and directors.

We have agreed to indemnify the underwriters and the underwriters have agreed to indemnify us against certain civil liabilities that may be incurred in connection with this offering, including certain liabilities under the Securities Act.

Item 15. Recent Sales of Unregistered Securities.

In June 12, 2017, our sponsor, purchased an aggregate of 14,375,000 of our Class B ordinary shares, for an aggregate offering price of $25,000, or approximately $0.002 per share. In August 2017, the sponsor surrendered 5,750,000 of its Class B ordinary shares for no consideration, resulting in the sponsor holding an aggregate of 8,625,000 Class B ordinary shares. The number of founder shares was determined based on the expectation that the founder shares would represent 20% of the outstanding shares after this offering. Such securities were issued in connection with our organization pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act.

Our sponsor is an accredited investor for purposes of Rule 501 of Regulation D under the Securities Act. The sole business of our sponsor is to act as our sponsor in connection with this offering.

In addition, our sponsor has committed, pursuant to a written agreement, to purchase from us an aggregate of 5,333,333 (or 5,933,333 if the underwriters’ over-allotment option is exercised in full) private placement warrants at $1.50 per warrant (for an aggregate purchase price of approximately $8,000,000 (or approximately $8,900,000 if the underwriters’ over-allotment option is exercised in full)). These purchases will take place on a private placement basis simultaneously with the completion of our initial public offering. These issuances will be made pursuant to the exemption from registration contained in Section 4(a)(2) of the Securities Act.

No underwriting discounts or commissions were paid with respect to such sales.

Item 16. Exhibits and Financial Statement Schedules.

(a)      The list of exhibits immediately preceding the signature page of this registration statement is incorporated herein by reference.

Item 17. Undertakings.

(a)      The undersigned registrant hereby undertakes to provide to the underwriter at the closing specified in the underwriting agreements, certificates in such denominations and registered in such names as required by the underwriter to permit prompt delivery to each purchaser.

(b)     Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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(c)      The undersigned registrant hereby undertakes that:

(1)      For purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

(2)      For the purpose of determining any liability under the Securities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

EXHIBIT INDEX

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*         Filed herewith.

***      Previously filed.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Houston, Texas, on the 1^st day of November, 2017.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

* By: /s/ Krishna Shivram                          
          Krishna Shivram, Attorney-in-Fact

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AUTHORIZED REPRESENTATIVE

Pursuant to the requirements of Section 6(a) of the Securities Act of 1933, the undersigned has signed this registration statement, solely in its capacity as the duly authorized representative of Sentinel Energy Services Inc., in the City of Houston, Texas on the 1^st day of November, 2017.

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