SC 13G/A

Name of Reporting Persons:

Blackstone Inc.

Check the Appropriate Box if a Member of a Group

(a) ☐ (b) ☒

SEC Use Only

Citizenship or Place of Organization:

Delaware

SC 13G/A 1 d719064dsc13ga.htm SC 13G/A SC 13G/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 4)*

MPLX LP

(Name of Issuer)

Common Units Representing Limited Partnership Interests

(Title of Class of Securities)

55336V100

(CUSIP Number)

December 31, 2023

(Date of Event which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

*	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).


CUSIP No. 55336V100				13G


CUSIP No. 55336V100				13G


CUSIP No. 55336V100				13G

Item 1(a). Name of Issuer:

MPLX LP (the “Issuer”)

Item 1(b). Address of Issuer’s Principal Executive Offices:

200 E. Hardin Street, Findlay, Ohio 45840

Item 2(a). Name of Person Filing

Item 2(b). Address of Principal Business Office

Item 2(c). Citizenship

Each of the following is hereinafter individually referred to as a “Reporting Person” and collectively as the “Reporting Persons.” This statement is filed on behalf of:

(i)

Blackstone Inc.

345 Park Avenue

New York, NY 10154

Citizenship: State of Delaware

(ii)

Blackstone Group Management L.L.C.

c/o Blackstone Inc.

345 Park Avenue

New York, NY 10154

Citizenship: State of Delaware

(iii)

Stephen A. Schwarzman

c/o Blackstone Inc.

345 Park Avenue

New York, NY 10154

Citizenship: United States

This Schedule 13G reflects Common Units (as defined below) held by funds or accounts that may be deemed to be indirectly controlled by Blackstone Inc. The sole holder of the Series II preferred stock of Blackstone Inc. is Blackstone Group Management L.L.C. Blackstone Group Management L.L.C. is wholly-owned by Blackstone’s senior managing directors and controlled by its founder, Stephen A. Schwarzman.

Each such Reporting Person may be deemed to beneficially own the Common Units reported herein, but neither the filing of this Schedule 13G nor any of its contents shall be deemed to constitute an admission that any Reporting Person is the beneficial owner of the Common Units referred to herein for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the “Act”), or for any other purpose and each of the Reporting Persons expressly disclaims beneficial ownership of such Common Units. The filing of this statement should not be construed to be an admission that any member of the Reporting Persons are members of a “group” for the purposes of Sections 13(d) and 13(g) of the Act.

Item 2(d). Title of Class of Securities:

Common units representing limited partnership interests (the “Common Units”).

Item 2(e). CUSIP Number:

55336V100

Item 3. If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

Not applicable.

Item 4. Ownership.

(a) Amount beneficially owned:

Calculation of the percentage of Common Units beneficially owned is based on 1,001,217,044 Common Units outstanding as of October 27, 2023, as reported in the Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on October 31, 2023. Each of the Reporting Persons may be deemed to be the beneficial owner of the Common Units listed on such Reporting Person’s cover page.

As of December 31, 2023, funds or accounts that may be deemed to be indirectly controlled by Blackstone Inc. held 23,413,432 Common Units.

(b) Percent of class:

Each of the Reporting Persons may be deemed to be the beneficial owner of the percentage of Common Units listed on such Reporting Person’s cover page.

(c) Number of Shares as to which the Reporting Person has:

(i)

Sole power to vote or to direct the vote:

See each cover page hereof.

(ii)

Shared power to vote or to direct the vote:

See each cover page hereof.

(iii)

Sole power to dispose or to direct the disposition of:

See each cover page hereof.

(iv)

Shared power to dispose or to direct the disposition of:

See each cover page hereof.

Item 5. Ownership of Five Percent or Less of a Class.

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following: ☒

Item 6. Ownership of More than Five Percent on Behalf of Another Person.

Not applicable.

Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company.

Not applicable.

Item 8. Identification and Classification of Members of the Group.

Not applicable.

Item 9. Notice of Dissolution of Group.

Not applicable.

Item 10. Certification.

Each of the Reporting Persons hereby makes the following certification:

By signing below the undersigned certifies that, to the best of its knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURE

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

Dated: February 9, 2024


BLACKSTONE INC.

By:		/s/ Tabea Hsi
Name:		Tabea Hsi
Title:		Senior Managing Director

BLACKSTONE GROUP MANAGEMENT L.L.C.

By:		/s/ Tabea Hsi
Name:		Tabea Hsi
Title:		Senior Managing Director

/s/ Stephen A. Schwarzman
Stephen A. Schwarzman

SEC Form SC 13G/A filed by MPLX LP (Amendment)