<SEC-DOCUMENT>0000899243-20-031650.txt : 20201119
<SEC-HEADER>0000899243-20-031650.hdr.sgml : 20201119
<ACCEPTANCE-DATETIME>20201119163016
ACCESSION NUMBER:		0000899243-20-031650
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20201117
FILED AS OF DATE:		20201119
DATE AS OF CHANGE:		20201119

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Fortress Acquisition Sponsor LLC
		CENTRAL INDEX KEY:			0001801364

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39277
		FILM NUMBER:		201329163

	BUSINESS ADDRESS:	
		STREET 1:		1345 AVENUE OF THE AMERICAS
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10105
		BUSINESS PHONE:		212-798-6100

	MAIL ADDRESS:	
		STREET 1:		1345 AVENUE OF THE AMERICAS
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10105

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Principal Holdings I LP
		CENTRAL INDEX KEY:			0001427223

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39277
		FILM NUMBER:		201329164

	BUSINESS ADDRESS:	
		STREET 1:		1345 AVENUE OF THE AMERICAS
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10105
		BUSINESS PHONE:		212 798 6100

	MAIL ADDRESS:	
		STREET 1:		1345 AVENUE OF THE AMERICAS
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10105

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MP Materials Corp. / DE
		CENTRAL INDEX KEY:			0001801368
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL MINING [1000]
		IRS NUMBER:				844465489

	BUSINESS ADDRESS:	
		STREET 1:		6720 VIA AUSTI PARKWAY
		STREET 2:		SUITE 450
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89119
		BUSINESS PHONE:		(702) 844-6111

	MAIL ADDRESS:	
		STREET 1:		6720 VIA AUSTI PARKWAY
		STREET 2:		SUITE 450
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89119

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Fortress Value Acquisition Corp.
		DATE OF NAME CHANGE:	20200128
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-11-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001427223</rptOwnerCik>
            <rptOwnerName>Principal Holdings I LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1345 AVENUE OF THE AMERICAS,</rptOwnerStreet1>
            <rptOwnerStreet2>46TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10105</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001801364</rptOwnerCik>
            <rptOwnerName>Fortress Acquisition Sponsor LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O 1345 AVENUE OF THE AMERICAS</rptOwnerStreet1>
            <rptOwnerStreet2>46TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10105</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock, par value $0.0001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2020-11-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>500000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>500000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Explanation of Responses</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock, par value $0.0001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2020-11-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9465000</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9965000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Explanation of Responses</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Class F Common Stock, par value $0.0001 per share</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-11-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>890000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A common stock, par value $0.0001 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>890000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9465000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Explanation of Responses</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Class F Common Stock, par value $0.0001 per share</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-11-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9465000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A common stock, par value $0.0001 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>9465000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Explanation of Responses</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares purchased by Fortress Acquisition Sponsor LLC (&quot;Sponsor&quot;) from Fortress Value Acquisition Corp. (the &quot;Issuer&quot;) in a private placement at a purchase price of $10.00 per share in connection with the consummation of the business combination with MP Mine Operations LLC and Secured Natural Resources LLC, on November 17, 2020 (the &quot;Business Combination&quot;), and pursuant to that certain Subscription Agreement, dated as of July 15, 2020.</footnote>
        <footnote id="F2">Represents the exchange of 5,933,333 private placement warrants directly held by Sponsor for 890,000 newly issued shares of Class F common stock of the Issuer, at an exchange ratio of one private placement warrant for 0.15 shares of Class F common stock pursuant to that certain Agreement and Plan of Merger, dated as of July 15, 2020, as amended, and that certain Warrant Exchange Agreement, dated as of July 15, 2020, by and between the Issuer and Sponsor in connection with the consummation of  Business Combination,.</footnote>
        <footnote id="F3">In connection with the consummation of the Business Combination, each issued and outstanding share of Class F common stock of the Issuer automatically converted into one share of Class A common stock of the Issuer, pursuant to the Issuer's certificate of incorporation in effect prior to the Business Combination. Under certain circumstances, all or a portion of such shares of Class A common stock are subject to forfeiture if certain stock price levels are not achieved on or before the tenth anniversary of the Business Combination.</footnote>
        <footnote id="F4">The member of Sponsor is Principal Holdings I LP, a Delaware limited partnership (&quot;Holdings&quot; and together with Sponsor, &quot;the Reporting Persons&quot;).</footnote>
        <footnote id="F5">Because of the relationship between the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any.</footnote>
        <footnote id="F6">Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Alexander Gillette, Authorized Signatory, Principal Holdings I LP</signatureName>
        <signatureDate>2020-11-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Alexander Gillette, Authorized Signatory, Fortress Acquisition Sponsor LLC</signatureName>
        <signatureDate>2020-11-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
