    <SEC-DOCUMENT>0000764065-20-000215-index.html : 20201026
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    <ACCEPTANCE-DATETIME>20200928062836
    ACCESSION NUMBER:		0000764065-20-000215
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		24
    CONFORMED PERIOD OF REPORT:	20200924
    ITEM INFORMATION:		Entry into a Material Definitive Agreement
    ITEM INFORMATION:		Unregistered Sales of Equity Securities
    ITEM INFORMATION:		Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20200928
    DATE AS OF CHANGE:		20200928

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			CLEVELAND-CLIFFS INC.
    		CENTRAL INDEX KEY:			0000764065
    		STANDARD INDUSTRIAL CLASSIFICATION:	METAL MINING [1000]
    		IRS NUMBER:				341464672
    		STATE OF INCORPORATION:			OH
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-08944
    		FILM NUMBER:		201201946

    	BUSINESS ADDRESS:
    		STREET 1:		200 PUBLIC SQUARE
    		STREET 2:		STE. 3300
    		CITY:			CLEVELAND
    		STATE:			OH
    		ZIP:			44114-2315
    		BUSINESS PHONE:		216-694-5700

    	MAIL ADDRESS:
    		STREET 1:		200 PUBLIC SQUARE
    		STREET 2:		STE. 3300
    		CITY:			CLEVELAND
    		STATE:			OH
    		ZIP:			44114-2315

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	CLIFFS NATURAL RESOURCES INC.
    		DATE OF NAME CHANGE:	20081015

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	CLEVELAND CLIFFS INC
    		DATE OF NAME CHANGE:	19920703
    </SEC-HEADER>
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    <SEQUENCE>1
    <FILENAME>clf-20200924.htm
    <DESCRIPTION>8-K
    <TEXT>
    Document 1 - file: clf-20200924.htm

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    <SEQUENCE>2
    <FILENAME>a20200924-8xkxex31.htm
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    <FILENAME>clf-20200924.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT
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