<SEC-DOCUMENT>0000049826-16-000205.txt : 20160513
<SEC-HEADER>0000049826-16-000205.hdr.sgml : 20160513
<ACCEPTANCE-DATETIME>20160513103557
ACCESSION NUMBER:		0000049826-16-000205
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160510
FILED AS OF DATE:		20160513
DATE AS OF CHANGE:		20160513

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ILLINOIS TOOL WORKS INC
		CENTRAL INDEX KEY:			0000049826
		STANDARD INDUSTRIAL CLASSIFICATION:	GENERAL INDUSTRIAL MACHINERY & EQUIPMENT [3560]
		IRS NUMBER:				361258310
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		155 HARLEM AVENUE
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025
		BUSINESS PHONE:		8477247500

	MAIL ADDRESS:	
		STREET 1:		155 HARLEM AVENUE
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Schlitz Lei Zhang
		CENTRAL INDEX KEY:			0001652579

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-04797
		FILM NUMBER:		161646514

	MAIL ADDRESS:	
		STREET 1:		155 HARLEM AVE.
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
<TEXT>
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        <issuerName>ILLINOIS TOOL WORKS INC</issuerName>
        <issuerTradingSymbol>ITW</issuerTradingSymbol>
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            <rptOwnerStreet2></rptOwnerStreet2>
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            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60025</rptOwnerZipCode>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President</officerTitle>
            <otherText></otherText>
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            <expirationDate>
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                <value>Performance Restricted Stock Unit (granted 2/12/2016)</value>
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                <value>0.0</value>
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                    <value>2993</value>
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    <footnotes>
        <footnote id="F1">This transaction was executed at multiple prices ranging from $105.453 to $105.46. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, Illinois Tool Works Inc. or a shareholder of Illinois Tool Works Inc. full information regarding the number of shares and prices at which the transaction was effected.</footnote>
        <footnote id="F2">Shares of common stock allocated to my account in the Illinois Tool Works Inc. Savings &amp; Investment Plan--Information reported as of May 10, 2016.</footnote>
        <footnote id="F3">Options vest in four (4) equal annual installments beginning one year from date of grant.</footnote>
        <footnote id="F4">Each restricted stock unit (RSU) represents a contingent right to receive one share of the Company's common stock.</footnote>
        <footnote id="F5">Each RSU vests 100% three years from the date of grant.</footnote>
        <footnote id="F6">Each performance restricted stock unit (PRSU) represents a contingent right to receive one share of the Company's common stock.</footnote>
        <footnote id="F7">Each PRSU vests 100% three years from date of grant if performance goals are met.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Lei Zhang Schlitz, by Janet O. Love, Deputy General Counsel &amp; Assistant Secretary, Attorney-In-Fact on File</signatureName>
        <signatureDate>2016-05-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
