-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 CVRtq8ikazi3uFkFqGQhFwxNt16jR0kQUSGT0lD9Pc/dQH9Z/h4SJodsSOFCyALf
 an6+AAE2CVebY2ApZkQuvw==

<SEC-DOCUMENT>0001344627-11-000003.txt : 20110216
<SEC-HEADER>0001344627-11-000003.hdr.sgml : 20110216
<ACCEPTANCE-DATETIME>20110216171431
ACCESSION NUMBER:		0001344627-11-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110214
FILED AS OF DATE:		20110216
DATE AS OF CHANGE:		20110216

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Fulks Kip J
		CENTRAL INDEX KEY:			0001344627

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33202
		FILM NUMBER:		11618442

	MAIL ADDRESS:	
		STREET 1:		UNDER ARMOUR INC
		STREET 2:		1020 HULL STREET
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21230

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Under Armour, Inc.
		CENTRAL INDEX KEY:			0001336917
		STANDARD INDUSTRIAL CLASSIFICATION:	APPAREL & OTHER FINISHED PRODS OF FABRICS & SIMILAR MATERIAL [2300]
		IRS NUMBER:				521990078
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1020 HULL STREET
		STREET 2:		3RD FLOOR
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21230
		BUSINESS PHONE:		410-454-6428

	MAIL ADDRESS:	
		STREET 1:		1020 HULL STREET
		STREET 2:		3RD FLOOR
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21230
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-02-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001336917</issuerCik>
        <issuerName>Under Armour, Inc.</issuerName>
        <issuerTradingSymbol>UA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001344627</rptOwnerCik>
            <rptOwnerName>Fulks Kip J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1020 HULL STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BALTIMORE</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21230</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP of Product</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-02-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>70</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>45100</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares sold pursuant to a 10b5-1 trading plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: /s/ John P. Stanton, Attorney in Fact  For: Kip J. Fulks</signatureName>
        <signatureDate>2011-02-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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