As filed with the Securities and Exchange Commission on June 15, 2022

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

MRC GLOBAL INC.

(Exact name of registrant as specified in its charter)

1301 McKinney Street, Suite 2300

Houston, Texas 77010

(877) 294-7574

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

MRC GLOBAL INC. OMNIBUS INCENTIVE PLAN, as amended

(Full title of the plan)

Daniel J. Churay

Executive Vice President – Corporate Affairs, General Counsel and Corporate Secretary

MRC Global Inc.

1301 McKinney Street, Suite 2300

Houston, Texas 77010

Telephone: (877) 294-7574

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

Copies to:

Brian P. Fenske

Norton Rose Fulbright US LLP

1301 McKinney, Suite 5100

Houston, Texas 77010

Telephone: (713) 651-5557

Facsimile: (713) 651-5246

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

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See definition 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 pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

EXPLANATORY NOTE

On May 5, 2022, at the 2022 Annual Meeting of Stockholders of MRC Global Inc. (the “Company”), the Company’s stockholders approved an amendment (the “Amendment”) to the MRC Global Inc. Omnibus Incentive Plan (as amended, the “Plan”). The Amendment provides that an additional 3,000,000 shares of the Company’s common stock, par value $0.01 per share (the “Common Stock”), may be issued under the Plan (the “Additional Shares”).

This Registration Statement on Form S-8 (this “Registration Statement”) is being filed by the Company to register the Additional Shares. The Additional Shares are in addition to (i) the 2,500,000 shares of Common Stock that may be issued under the Plan pursuant to the Company’s Registration Statement on Form S-8 (File No. 333-231222) filed with the Securities and Exchange Commission (the “Commission”) on May 3, 2019, (ii) the 4,250,000 shares (less the 102,525 Remaining Shares, which is defined therein) of Common Stock that may be issued under the Plan pursuant to the Company’s Registration Statement on Form S-8 (File No. 333-206455) filed with the Commission on August 18, 2015, and (iii) the 3,250,000 shares of Common Stock that may be issued under the Plan pursuant to the Company’s Registration Statement on Form S-8 (File No. 333-180777) filed with the Commission on April 17, 2012 (collectively, the “Prior Registration Statements”). Pursuant to General Instruction E to Form S-8 under the Securities Act of 1933, as amended (the “Securities Act”), the contents of the Prior Registration Statements are incorporated by reference into this Registration Statement, except to the extent supplemented, amended and superseded by the information set forth herein.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

SIGNATURES

Pursuant to the requirements of the Securities Act, MRC Global Inc. certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Houston, State of Texas, on June 15, 2022.

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below, the undersigned officers and directors of MRC Global Inc., hereby severally constitute and appoint Rob Saltiel, Kelly Youngblood and Daniel J. Churay, and each of them singly (with full power to each of them to act alone), his true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them for him and in his name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

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

Exhibit 5.1

June 15, 2022

MRC Global Inc.

1301 McKinney Street, Suite 2300

Houston, TX 77010

Ladies and Gentlemen:

We have acted as counsel to MRC Global Inc., a Delaware corporation (the “Company”), in connection with the registration under the Securities Act of 1933, as amended (the “Securities Act”), of an additional 3,000,000 shares (the “Shares”) of the Company’s common stock, par value $0.01 per share, that are reserved for issuance under the MRC Global Inc. Omnibus Incentive Plan, as amended (the “Plan”), as described in the Company’s Registration Statement on Form S-8 (as may subsequently be amended, the “Registration Statement”), which was filed with the Securities and Exchange Commission (the “SEC”) on June 15, 2022.

In connection with the foregoing, we have examined the Plan and originals or copies of certain corporate records of the Company, certificates and other communications of public officials, certificates of officers of the Company and such other documents as we have deemed relevant or necessary for the purpose of rendering the opinions expressed herein. As to questions of fact material to those opinions, we have, to the extent we deemed appropriate, relied on certificates of officers of the Company and on certificates and other communications of public officials. We have assumed that the persons identified to us as officers of the Company are actually serving as such and that any certificates representing the Shares will be properly executed by one or more such persons. We have assumed the effectiveness of the Registration Statement pursuant to the Securities Act. We have assumed the genuineness of all signatures on, and the authenticity of, all documents submitted to us as originals, the conformity to authentic original documents of all documents submitted to us as copies thereof, the due authorization, execution and delivery by the parties thereto other than the Company of all documents examined by us, that the Company will receive any required consideration for such Shares and the legal capacity of each individual who signed any of those documents.

Norton Rose Fulbright US LLP is a limited liability partnership registered under the laws of Texas.

Norton Rose Fulbright US LLP, Norton Rose Fulbright LLP, Norton Rose Fulbright Australia, Norton Rose Fulbright Canada LLP, Norton Rose Fulbright South Africa (incorporated as Deneys Reitz, Inc.), each of which is a separate legal entity, are members of Norton Rose Fulbright Verein, a Swiss Verein. Details of each entity, with certain regulatory information, are at nortonrosefulbright.com. Norton Rose Fulbright Verein helps coordinate the activities of the members but does not itself provide legal services to clients.

MRC Global Inc.

June 15, 2022

Page 2

Based upon the foregoing, we are of the opinion that the Shares, when issued and sold in the manner referred to in the Plan and pursuant to the agreements that accompany the Plan, will be validly issued, fully paid and nonassessable.

The opinions expressed herein are limited exclusively to applicable federal laws of the United States of America, and applicable provisions of, respectively, the Delaware Constitution, the Delaware General Corporation Law and reported judicial interpretations of such law, in each case as currently in effect, and we are expressing no opinion as to the effect of the laws of any other jurisdiction.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and the reference to this firm wherever it appears in the Registration Statement. This consent is not to be construed as an admission that we are a party whose consent is required to be filed with the Registration Statement under the provisions of the Securities Act or the rules and regulations of the SEC promulgated thereunder.

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the Registration Statement on Form S-8 pertaining to the MRC Global Inc. Omnibus Incentive Plan, as amended of our reports dated February 16, 2022, with respect to the consolidated financial statements of MRC Global Inc. and the effectiveness of internal control over financial reporting of MRC Global Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2021, filed with the Securities and Exchange Commission.

/s/ ERNST & YOUNG LLP

Houston, Texas

June 15, 2022

Exhibit 107

Calculation of Filing Fee Tables

Form S-8

(Form Type)

MRC GLOBAL INC.

(Exact Name of Registrant as Specified in its Charter)

Table 1: Newly Registered Securities