<SEC-DOCUMENT>0001862894-26-000002.txt : 20260114
<SEC-HEADER>0001862894-26-000002.hdr.sgml : 20260114
<ACCEPTANCE-DATETIME>20260114194316
ACCESSION NUMBER:		0001862894-26-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260112
FILED AS OF DATE:		20260114
DATE AS OF CHANGE:		20260114

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Hoops Elliot Dean
		CENTRAL INDEX KEY:			0001862894
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39277
		FILM NUMBER:		26534426

	MAIL ADDRESS:	
		STREET 1:		1700 S. PAVILION CENTER DR.
		STREET 2:		SUITE 800
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89135

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MP Materials Corp. / DE
		CENTRAL INDEX KEY:			0001801368
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL MINING [1000]
		ORGANIZATION NAME:           	01 Energy & Transportation
		EIN:				844465489
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1700 S. PAVILION CENTER DR.
		STREET 2:		SUITE 800
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89135
		BUSINESS PHONE:		(702) 844-6111

	MAIL ADDRESS:	
		STREET 1:		1700 S. PAVILION CENTER DR.
		STREET 2:		SUITE 800
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89135

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Fortress Value Acquisition Corp.
		DATE OF NAME CHANGE:	20200128
</SEC-HEADER>
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<SEQUENCE>1
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<DESCRIPTION>FORM 4
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    <periodOfReport>2026-01-12</periodOfReport>

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    <issuer>
        <issuerCik>0001801368</issuerCik>
        <issuerName>MP Materials Corp. / DE</issuerName>
        <issuerTradingSymbol>MP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001862894</rptOwnerCik>
            <rptOwnerName>Hoops Elliot Dean</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1700 S. PAVILION CENTER DRIVE, SUITE 800</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89135</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>General Counsel and Secretary</officerTitle>
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                <transactionCode>A</transactionCode>
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                    <value>69.30</value>
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                    <value>D</value>
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                    <value>82790</value>
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                <value>Common Stock</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The securities reported are restricted stock units that vest in four annual installments beginning on the first anniversary of the grant date. Each restricted stock unit represents the contingent right to receive, upon vesting of the unit, one share of the issuer's common stock.</footnote>
        <footnote id="F2">Represents the number of shares of Common Stock received upon vesting of restricted stock units with performance conditions award previously granted to the reporting person on February 23, 2023. Under the terms of this award, the restricted stock units with performance conditions cliff vest upon the conclusion of the three-year performance period from 01/01/2023 through 12/31/2025 and the certification of the Company's achievement of the pre-established performance conditions based on the relative total shareholder return of the Company's share price compared to the S&amp;P 400 Index and S&amp;P 400 Materials Index.</footnote>
        <footnote id="F3">Represents shares withheld to satisfy tax withholding obligations applicable to the vesting of restricted stock units with performance conditions that vested on January 12, 2026.</footnote>
        <footnote id="F4">Represents shares withheld to satisfy tax withholding obligations applicable to the vesting of restricted stock units that vested on January 12, 2026.</footnote>
        <footnote id="F5">Represents shares withheld to satisfy tax withholding obligations applicable to the vesting of restricted stock units that vested on January 13, 2026.</footnote>
        <footnote id="F6">Represents shares withheld to satisfy tax withholding obligations applicable to the vesting of restricted stock units that vested on January 14, 2026.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Elliot D. Hoops</signatureName>
        <signatureDate>2026-01-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
