<SEC-DOCUMENT>0001660112-19-000002.txt : 20190806
<SEC-HEADER>0001660112-19-000002.hdr.sgml : 20190806
<ACCEPTANCE-DATETIME>20190806205817
ACCESSION NUMBER:		0001660112-19-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190805
FILED AS OF DATE:		20190806
DATE AS OF CHANGE:		20190806

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mendoza Marie
		CENTRAL INDEX KEY:			0001660112

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34460
		FILM NUMBER:		191003636

	MAIL ADDRESS:	
		STREET 1:		10680 TREENA STREET, SUITE 600
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KRATOS DEFENSE & SECURITY SOLUTIONS, INC.
		CENTRAL INDEX KEY:			0001069258
		STANDARD INDUSTRIAL CLASSIFICATION:	GUIDED MISSILES & SPACE VEHICLES & PARTS [3760]
		IRS NUMBER:				133818604
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1229

	BUSINESS ADDRESS:	
		STREET 1:		10680 TREENA STREET
		STREET 2:		SUITE 600
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131
		BUSINESS PHONE:		858-812-7300

	MAIL ADDRESS:	
		STREET 1:		10680 TREENA STREET
		STREET 2:		SUITE 600
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	WIRELESS FACILITIES INC
		DATE OF NAME CHANGE:	19990817
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-08-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001069258</issuerCik>
        <issuerName>KRATOS DEFENSE &amp; SECURITY SOLUTIONS, INC.</issuerName>
        <issuerTradingSymbol>KTOS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001660112</rptOwnerCik>
            <rptOwnerName>Mendoza Marie</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>10680 TREENA STREET, SUITE 600</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92131</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP &amp; General Counsel</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-08-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4800</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.1234</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20189</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-08-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9193</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.8691</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10996</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Open market sale of Issuer's common stock made in accordance with Issuer's trading policies.</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 $20.00 to $20.25 inclusive. The reporting person undertakes to provide to Issuer, any security holder of Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote to this Form 4.</footnote>
        <footnote id="F3">The price reported in Column 4 is a weighted average price.  These shares were sold in multiple transactions at prices ranging from $19.75 to $20.00 inclusive. The reporting person undertakes to provide to Issuer, any security holder of Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote to this Form 4.</footnote>
        <footnote id="F4">Includes 235 shares purchased through Issuer's Employee Stock Purchase Plan and approximately 10,761 shares held in Issuer's 401(k) Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Marie C. Mendoza, by Eva Yee, Attorney-In-Fact</signatureName>
        <signatureDate>2019-08-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
