<SEC-DOCUMENT>0001020569-18-000018.txt : 20180222
<SEC-HEADER>0001020569-18-000018.hdr.sgml : 20180222
<ACCEPTANCE-DATETIME>20180222173223
ACCESSION NUMBER:		0001020569-18-000018
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180216
FILED AS OF DATE:		20180222
DATE AS OF CHANGE:		20180222

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Bicks Edward
		CENTRAL INDEX KEY:			0001667756

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13045
		FILM NUMBER:		18633723

	MAIL ADDRESS:	
		STREET 1:		C/O IRON MOUNTAIN INCORPORATED
		STREET 2:		ONE FEDERAL STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IRON MOUNTAIN INC
		CENTRAL INDEX KEY:			0001020569
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				232588479
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE FEDERAL STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		617-535-4781

	MAIL ADDRESS:	
		STREET 1:		ONE FEDERAL STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IRON MOUNTAIN INC/PA
		DATE OF NAME CHANGE:	20000201

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PIERCE LEAHY CORP
		DATE OF NAME CHANGE:	19960807
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
<TEXT>
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        <issuerTradingSymbol>IRM</issuerTradingSymbol>
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        </reportingOwnerId>
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            <rptOwnerStreet2>ONE FEDERAL STREET</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
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            <isOther>0</isOther>
            <officerTitle>SVP, Strategy</officerTitle>
            <otherText></otherText>
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                    <value>853</value>
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    <footnotes>
        <footnote id="F1">This transaction is being reported to reflect the full vesting of performance units (&quot;PUs&quot;) initially granted to the Reporting Person on February 19, 2015.  Effective February 16, 2018, the Compensation Committee of Iron Mountain Incorporated's Board of Directors (the &quot;Compensation Committee&quot;) determined the actual award of PUs under the grant after completion of the relevant performance period, and the PUs vested on February 20, 2018.</footnote>
        <footnote id="F2">This acquisition is reported to reflect the partial vesting of restricted stock units (&quot;RSUs&quot;) previously granted to the Reporting Person on February 19, 2015.</footnote>
        <footnote id="F3">This acquisition is reported to reflect the partial vesting of RSUs previously granted to the Reporting Person on February 18, 2016.</footnote>
        <footnote id="F4">Each PU represents a contingent right to receive one share of Iron Mountain Incorporated common stock (&quot;Common Stock&quot;).</footnote>
        <footnote id="F5">The PUs were initially granted to the Reporting Person on February 19, 2015, and effective February 16, 2018 the Compensation Committee determined the actual award of PUs under the grant after completion of the relevant performance period.</footnote>
        <footnote id="F6">The PUs were initially granted to the Reporting Person on February 19, 2015 and fully vested on February 20, 2018.</footnote>
        <footnote id="F7">Each RSU represents a contingent right to receive one share of Common Stock.</footnote>
        <footnote id="F8">The RSUs were granted to the Reporting Person on February 19, 2015 and have fully vested.</footnote>
        <footnote id="F9">The RSUs, representing a contingent right to receive a total of 2,562 shares of Common Stock, were granted to the Reporting Person on February 18, 2016 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Elizabeth Tammaro, under Power of Attorney dated May 26, 2016, from Ned Bicks</signatureName>
        <signatureDate>2018-02-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
