<SEC-DOCUMENT>0000899243-22-037138.txt : 20221129
<SEC-HEADER>0000899243-22-037138.hdr.sgml : 20221129
<ACCEPTANCE-DATETIME>20221129165600
ACCESSION NUMBER:		0000899243-22-037138
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20221125
FILED AS OF DATE:		20221129
DATE AS OF CHANGE:		20221129

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Spice Adam C.
		CENTRAL INDEX KEY:			0001509421

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39560
		FILM NUMBER:		221433405

	MAIL ADDRESS:	
		STREET 1:		2051 PALOMAR AIRPORT ROAD
		STREET 2:		SUITE 100
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92011

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Rocket Lab USA, Inc.
		CENTRAL INDEX KEY:			0001819994
		STANDARD INDUSTRIAL CLASSIFICATION:	GUIDED MISSILES & SPACE VEHICLES & PARTS [3760]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3881 MCGOWEN STREET
		CITY:			LONG BEACH
		STATE:			CA
		ZIP:			90808
		BUSINESS PHONE:		714-465-5737

	MAIL ADDRESS:	
		STREET 1:		3881 MCGOWEN STREET
		CITY:			LONG BEACH
		STATE:			CA
		ZIP:			90808

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Vector Acquisition Corp
		DATE OF NAME CHANGE:	20200803
</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>2022-11-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001819994</issuerCik>
        <issuerName>Rocket Lab USA, Inc.</issuerName>
        <issuerTradingSymbol>RKLB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001509421</rptOwnerCik>
            <rptOwnerName>Spice Adam C.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ROCKET LAB USA, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3881 MCGOWEN STREET</rptOwnerStreet2>
            <rptOwnerCity>LONG BEACH</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90808</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2022-11-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>45659</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>4.22</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1750357</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents the sale of Common Shares pursuant to a &quot;sell-to-cover&quot; transaction in order to satisfy applicable tax withholding obligations in connection with the vesting and settlement of restricted stock units previously granted to the reporting person.</footnote>
        <footnote id="F2">The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $4.14 to $4.525, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of Common Shares sold at each separate price within the range set forth in this footnote (2) to this Form 4.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Janine Wong as Attorney-in-Fact for Adam Spice</signatureName>
        <signatureDate>2022-11-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
