<SEC-DOCUMENT>0001014803-17-000002.txt : 20171211
<SEC-HEADER>0001014803-17-000002.hdr.sgml : 20171211
<ACCEPTANCE-DATETIME>20171211084858
ACCESSION NUMBER:		0001014803-17-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20171207
FILED AS OF DATE:		20171211
DATE AS OF CHANGE:		20171211

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Jarvis Scot B
		CENTRAL INDEX KEY:			0001014803
		STANDARD INDUSTRIAL CLASSIFICATION:	RADIO TELEPHONE COMMUNICATIONS [4812]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34460
		FILM NUMBER:		171248522

	MAIL ADDRESS:	
		STREET 1:		C/O KRATOS DEFENSE & SECURITY SOLUTIONS
		STREET 2:		4810 EASTGATE MALL
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121

	FORMER NAME:	
		FORMER CONFORMED NAME:	JARVIS SCOT
		DATE OF NAME CHANGE:	19960517

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:			1225

	BUSINESS ADDRESS:	
		STREET 1:		4820 EASTGATE MALL
		STREET 2:		SUITE 200
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121
		BUSINESS PHONE:		858-812-7300

	MAIL ADDRESS:	
		STREET 1:		4820 EASTGATE MALL
		STREET 2:		SUITE 200
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121

	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>2017-12-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001014803</rptOwnerCik>
            <rptOwnerName>Jarvis Scot B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O KRATOS DEFENSE &amp; SECURITY SOLUTIONS</rptOwnerStreet1>
            <rptOwnerStreet2>4820 EASTGATE MALL</rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92121</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-12-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.4965</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>95200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Open market purchase 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 purchased in multiple transactions at prices ranging from $10.4892 to $10.50 inclusive.  The Reporting Person undertakes to provide to Issuer, any security holder of Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote to this Form 4.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Scot B. Jarvis, by Eva Yee, Attorney-In-Fact</signatureName>
        <signatureDate>2017-12-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
