UNITED STATES

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549

SCHEDULE 13D/A

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)*

Liberty Oilfield Services Inc.

(Name of Issuer)

Class A Common Stock, $0.01 par value per share

(Title of Class of Securities)

53115L 104

(CUSIP Number)

Dianna Rosser Aprile

c/o Riverstone Holdings, LLC

712 Fifth Avenue, 36th Floor

New York, New York 10019

(212) 993-0076

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

(with a copy to)

Jeffrey S. Hochman

Willkie Farr & Gallagher LLP

787 Seventh Avenue New York, New York 10019

(212) 728-8000

November 5, 2019

(Date of Event Which Requires Filing of Statement on Schedule 13D)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), checking the following box. ☐

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Explanatory Note

This Amendment No. 4 to Schedule 13D (this “Amendment No. 4”) amends and supplements the Schedule 13D filed with the Securities and Exchange Commission on January 26, 2018, as amended by Amendment No. 1 to Schedule 13D/A, filed on September 14, 2018, as amended by Amendment No. 2 to Schedule 13D/A, filed on July 11, 2019 and as amended by Amendment No. 3 to Schedule 13D/A, filed on July 23, 2019 (the “Current Schedule 13D”), relating to the Class A common stock, par value $0.01 per share (the “Common A Shares”), of Liberty Oilfield Services Inc. (the “Issuer”). The Common A Shares and Class B common stock, par value $0.01 per share, of the Issuer (the “Common B Shares” and, together with the Common A Shares, the “Common Shares”) are treated as a single class for purposes of this Schedule 13D because they vote together as a single class. Capitalized terms used herein without definition shall have the meaning set forth in the Current Schedule 13D.

ITEM 4. PURPOSE OF TRANSACTION

Item 4 of the Current Schedule 13D is hereby amended and supplemented as follows:

On November 5, 2019, R/C IV Liberty Holdings, L.P. (“R/C Liberty”) sold 4,016,965 Common A Shares and R/C Energy IV Direct Partnership, L.P. (“R/C Direct”) sold 1,733,035 Common A Shares at a price of $9.61 per share through Morgan Stanley & Co. LLC in accordance with Rule 144 under the Securities Act of 1933.  In connection with such sale by R/C Liberty, 4,016,965 Units and the related Common B Shares were redeemed by the Issuer for an equal amount of Common A Shares.

ITEM 5.          INTEREST IN SECURITIES OF THE ISSUER

Item 5 of the Current Schedule 13D is hereby amended and restated in its entirety as follows:

(a)

and (b)

The below table sets forth the number of Common Shares directly and beneficially owned by each of the Reporting Persons.  The shares directly owned by R/C Direct and R/C Liberty are deemed to be beneficially owned by Riverstone/Carlyle, their general partner, and all of such shares are deemed to be beneficially owned by R/C GP, the general partner of Riverstone/Carlyle.  Accordingly, as indicated with respect to such shares listed as beneficially owned in the below table, the applicable Reporting Persons have shared voting power to vote and direct the vote of, and have shared power to dispose and direct the disposition of, such shares.  None of the Reporting Persons have the sole power to vote or direct the vote, or the sole power to dispose or direct the disposition of, the shares listed in the table below.  In addition, by virtue of the Stockholders Agreement and the other agreements among certain of the Reporting Persons as described in this Schedule 13D, the Reporting Persons may be deemed to constitute a “group” within the meaning of Section 13(d)(3) under the Securities Exchange Act of 1934, as amended, and Rule 13d-5(1) thereunder.   Each Reporting Person expressly disclaims, to the extent permitted by applicable law, beneficial ownership of any Common Shares held by the other Reporting Persons.

(1)	Based on an aggregate of 75,868,419 Common A Shares and 36,655,925 Common B Shares outstanding as of October 25, 2019, as reported in the Issuer’s quarterly report on Form 10-Q for the quarter ended September 30, 2019.

(2)	Represents 12,850,432 Common A Shares and 21,204,564 Common B Shares and includes Common Shares directly owned by R/C Direct and R/C Liberty.

By virtue of the various agreements and arrangements among the Reporting Persons described in this Schedule 13D and the members of the Voting Group (the members of the Voting Group other than any Reporting Persons, the “Non-Riverstone Members”), the Non-Riverstone Members may be deemed to be members of a “group” with the Reporting Persons. None of the Non-Riverstone Members are Reporting Persons on this Schedule 13D, and any obligations any of them may have under Section 13(d) of the Act would have to be satisfied on one or more separate filings. To the extent that any Non-Riverstone Members beneficially owns Equity Interests, the Reporting Persons may be deemed to beneficially own any such Equity Interests, but expressly disclaim, to the extent permitted by applicable law, beneficial ownership thereof.

(c)	None of the Reporting Persons has effected any transactions of the Common A Shares during the 60 days preceding the date of this report, except as described in Items 4 and 6 of this Schedule 13D, which information is incorporated herein by reference.

(d)	Not applicable.

(e)	Not applicable.

Item 6 of the Current Schedule 13D is amended and supplemented as follows:

In connection with the sales described in Item 4 above, on November 5, 2019, each of R/C Direct and R/C Liberty entered into a 30 day Lock-Up Agreement with Morgan Stanley & Co. LLC.  Copies of each Lock-Up Agreement are attached as exhibits 7.11 and 7.12 to this Schedule 13D and are incorporated herein by reference.

ITEM 7.          MATERIAL TO BE FILED AS EXHIBITS

Item 7 of the Current Schedule 13D is amended and supplemented by adding the following exhibit:

7.11	Lock-Up Agreement of R/C Direct.

7.12	Lock-Up Agreement of R/C Liberty.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete, and correct.

Dated as of November 7, 2019

RIVERSTONE/CARLYLE ENERGY PARTNERS IV, L.P.

By: R/C Energy GP IV, LLC, its general partner

By: /s/ Peter Haskopoulos          

Name: Peter Haskopoulos

Title: Managing Director

R/C ENERGY IV DIRECT PARTNERSHIP, L.P.

By: Riverstone/Carlyle Energy Partners IV, L.P., its general partner

By: R/C Energy GP IV, LLC, its general partner

By: /s/ Peter Haskopoulos          

Name: Peter Haskopoulos

Title: Managing Director

R/C IV LIBERTY HOLDINGS, L.P.

By: Riverstone/Carlyle Energy Partners IV, L.P., its general partner

By: R/C Energy GP IV, LLC, its general partner

By: /s/ Peter Haskopoulos          

Name: Peter Haskopoulos

Title: Managing Director

R/C ENERGY GP IV, LLC

By: /s/ Peter Haskopoulos          

Name: Peter Haskopoulos

Title: Managing Director

Exhibit 7.11

LOCK-UP LETTER

November 5, 2019

Morgan Stanley & Co. LLC
1585 Broadway
New York, NY 10036

Ladies and Gentlemen:

The undersigned proposes to sell 1,733,035 Shares (the “Shares”) of Class A common stock, par value $0.01 per share (the “Common Stock”), of Liberty Oilfield Services Inc. (the “Company”) through Morgan Stanley & Co. LLC (“Morgan Stanley”) in accordance with the requirements of Rule 144 under the Securities Act of 1933, as amended (the “Transaction”).

To induce Morgan Stanley to enter into the Transaction, except pursuant to the Transaction, the undersigned hereby agrees that, without the prior written consent of Morgan Stanley, it will not, during the period commencing on the date hereof and ending 30 days after the date hereof (the “Restricted Period”), (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock beneficially owned (as such term is used in Rule 13d-3 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), by the undersigned or any other securities so owned convertible into or exercisable or exchangeable for Common Stock or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise.  The foregoing sentence shall not apply to (a) transactions relating to shares of Common Stock or other securities acquired in open market transactions after the date hereof, provided that no filing by any party under Section 16(a) of the Exchange Act, shall be required or shall be voluntarily made in connection with subsequent sales of Common Stock or other securities acquired in such open market transactions, (b) transfers of shares of Common Stock or any security convertible into Common Stock as a bona fide gift or gifts, (c) distributions of shares of Common Stock or any security convertible into Common Stock to limited partners or stockholders of the undersigned, and (d) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act for the transfer of shares of Common Stock, provided that (i) such plan does not provide for the transfer of Common Stock during the Restricted Period and (ii) to the extent a public announcement or filing under the Exchange Act, if any, is

required of or voluntarily made by or on behalf of the Company or the undersigned regarding the establishment of such plan, such announcement or filing shall include a statement to the effect that no transfer of Common Stock may be made under such plan during the Restricted Period; provided further that in the case of any transfer or distribution pursuant to clause (b) or (c), (i) each donee or distributee shall sign and deliver a lock‑up letter substantially in the form of this letter and (ii) the undersigned shall not be required to, and shall not voluntarily, file a report under Section 16(a) of the Exchange Act, reporting a reduction in beneficial ownership of shares of Common Stock during the Restricted Period.  In addition, the undersigned agrees that, without the prior written consent of Morgan Stanley, it will not, during the Restricted Period, make any demand for or exercise any right with respect to, the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock.  The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar against the transfer of the undersigned’s shares of Common Stock except in compliance with the foregoing restrictions.

The undersigned understands that Morgan Stanley is relying upon this agreement in proceeding toward consummation of the Transaction.  The undersigned further understands that this agreement is irrevocable and shall be binding upon the undersigned’s successors and assigns.

Whether or not the Transaction actually occurs depends on a number of factors, including market conditions.

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