<SEC-DOCUMENT>0001550096-17-000004.txt : 20170613
<SEC-HEADER>0001550096-17-000004.hdr.sgml : 20170613
<ACCEPTANCE-DATETIME>20170613150017
ACCESSION NUMBER:		0001550096-17-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170609
FILED AS OF DATE:		20170613
DATE AS OF CHANGE:		20170613

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:			Hartnett John R.
		CENTRAL INDEX KEY:			0001550096

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-04797
		FILM NUMBER:		17908675

	MAIL ADDRESS:	
		STREET 1:		155 HARLEM AVE
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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            <rptOwnerStreet2>155 HARLEM AVENUE</rptOwnerStreet2>
            <rptOwnerCity>GLENVIEW</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60025</rptOwnerZipCode>
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            <isTenPercentOwner>0</isTenPercentOwner>
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            <officerTitle>Executive Vice President</officerTitle>
            <otherText></otherText>
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    <footnotes>
        <footnote id="F1">This transaction was executed in multiple trades at prices ranging from $144.79 to $145.12. 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 stockholder of Illinois Tool Works Inc. full information regarding the number of shares and prices at which the transaction was effected.</footnote>
        <footnote id="F2">Options vest in four (4) equal annual installments beginning one year from date of grant.</footnote>
        <footnote id="F3">Each performance restricted stock unit (PRSU) and performance share unit (PSU) represents a contingent right to receive one share of the Company's common stock.</footnote>
        <footnote id="F4">Each PRSU and PSU vests 100% three years from the date of grant if performance goals are met.</footnote>
        <footnote id="F5">PSUs accrue dividends in shares of common stock, subject to fulfillment of vesting period and performance goals; the PSUs shown include dividend equivalents accrued to date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>John R. Hartnett, by Janet O. Love, Deputy General Counsel &amp; Assistant Secretary, Attorney-In-Fact on File</signatureName>
        <signatureDate>2017-06-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
