SIXTH SUPPLEMENTAL INDENTURE

EXHIBIT -4.11

SIXTH SUPPLEMENTAL INDENTURE

     SIXTH SUPPLEMENTAL INDENTURE dated as of September 3, 2007 (this “Supplemental Indenture”) among ISPAT INLAND ULC, a Nova Scotia unlimited liability company, as issuer (the “Issuer”), the Guarantors and LASALLE BANK NATIONAL ASSOCIATION, as Trustee (the “Trustee”).

RECITALS

     WHEREAS, the Issuer, the Guarantors and the Trustee have entered into an Indenture dated as of March 25, 2004, as supplemented (as so supplemented, the “Indenture”);

     WHEREAS, pursuant to Section 8.01 of the Indenture, the Issuer and the Guarantors, when authorized by a Board Resolution, and the Trustee, when an Officers’ Certificate is provided stating that such amendment or supplement complies with the provisions of Section 8.01, may amend or supplement the Indenture without notice to or consent of any Holder to provide for the assumption by a successor entity of the obligations of Parent under the Indenture;

     WHEREAS, Mittal Steel Company N.V., a Netherlands company (formerly known as Ispat International N.V. and the “Parent” under the Indenture), merged by absorption (the “Step 1 Merger”) into its wholly-owned subsidiary, ArcelorMittal, a Luxembourg company the (“Successor Parent”), effective as of September 3, 2007, and as a result of the Step 1 Merger, the Parent has ceased to exist and has transferred by law all of its assets and liabilities to the Successor Parent;

     WHEREAS, Luxembourg, the country under which the Successor Parent is organized, was a member nation of the European Union on March 25, 2004; and

     WHEREAS, the Issuer, the Guarantors and Trustee wish to enter into this Supplemental Indenture pursuant to Section 4.22(1) of the Indenture in order to reflect the assumption by the Successor Parent of all the obligations of the Parent under its Note Guarantee and the Indenture.

     NOW, THEREFORE, each party agrees as follows for the benefit of the other parties and for the equal and ratable benefit of the Holders of the Notes, as follows:

ARTICLE 1

ASSUMPTION

     SECTION 1.1 The Successor Parent hereby expressly assumes all obligations of the Parent under its Note Guarantee and the Indenture, and the term “Parent,” as used in the Indenture and the Collateral Documents, shall, from and after the date hereof, mean and refer to the Successor Parent.

ARTICLE 2

MISCELLANEOUS

     SECTION 2.1 This Supplemental Indenture is executed and shall be construed as an indenture supplemental to the Indenture with respect to the Notes and, as provided in the Indenture, this Supplemental Indenture forms a part thereof with respect to the Notes. Except as herein modified, the

Indenture is in all respects ratified and confirmed with respect to the Notes and all the terms, provisions and conditions thereof shall be and remain in full force and effect with respect to the Notes and every Holder of Notes shall be bound hereby. Except as expressly otherwise defined, the use of the terms and expressions herein is in accordance with the definitions, uses and constructions contained in the Indenture.

     SECTION 2.2 If any provision of this Supplemental Indenture limits, qualifies or conflicts with any other provision hereof or of the Indenture that is required to be included in the Indenture by any of the provisions of the TIA, such required provision shall control.

     SECTION 2.3 Unless otherwise indicated, capitalized terms used herein without definition shall have the meanings specified therefor in Section 1.01 of the Indenture.

     SECTION 2.4 If any provision of this Supplemental Indenture shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

     SECTION 2.5 This Supplemental Indenture shall be construed in accordance with, and governed by, the laws of the State of New York.

     SECTION 2.6 This Supplemental Indenture may be executed in any number of counterparts, each of which shall be an original but such counterparts shall together constitute but one and the same instrument.

     SECTION 2.7 This Supplemental Indenture shall become effective as of the date first above written.

     IN WITNESS WHEREOF, the parties have caused this Sixth Supplemental Indenture to be executed on December 21, 2007 effective as of the date first above written.

	ISPAT INLAND ULC, as Issuer
	By:	/s/ Xxxxxx Xxxxx
		Name:	Xxxxxx Xxxxx
		Title:

	ARCELORMITTAL (successor by merger), as a Guarantor and Successor Parent
	By:	/s/ E. S. De Vries
		Name:	E. S. De Vries
		Title:	Group Treasurer
	By:	/s/ Xxxxx Xxxxx
		Name:	Xxxxx Xxxxx
		Title:	Group General Counsel

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		ARCELORMITTAL USA INC. (formerly, Mittal Steel
		USA Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx
				Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL PARTNERSHIP (formerly, Mittal
		Steel USA Partnership), as a Guarantor
		By:		Mittal Canada Inc., a partner
		By:		/s/ Xxxxxx D’Auteuil Name: Xxxxxx D’Auteuil
				Title: Treasurer
		3019693 NOVA SCOTIA U.L.C.
		as a Guarantor
		By:		/s/ Xxxxxx Xxxxx Name: Xxxxxx Xxxxx
				Title:
		ARCELORMITTAL FINANCE LLC (formerly, Xxxxx
		Steel USA-Finance LLC), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx
				Name: Xxxxxx X. XxXxx
				Title: Treasurer
		XXXXXXX TRUCKING COMPANY, INC.,
		as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL USA INCOAL INC. (formerly,
		Incoal Company), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer

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		ARCELORMITTAL MINORCA MINE INC. (formerly,
		Mittal Steel USA-Minorca Mine Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL SERVICE INC. (formerly, Mittal
		Steel USA Service Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL CLEVELAND INC. (formerly, ISG
		Cleveland Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL WEIRTON INC. (formerly, ISG
		Weirton Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL HENNEPIN INC. (formerly, ISG
		Hennepin Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx
				Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL INDIANA HARBOR INC.
		(formerly, ISG Indiana Harbor Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer

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		ARCELORMITTAL XXXXXX INC.
		(formerly ISG Xxxxxx Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL RIVERDALE INC. (formerly, ISG Riverdale Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		MITTAL STEEL USA — VENTURE INC. (formerly, ISG Venture Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL PLATE LLC (formerly ISG Plate LLC), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ISG SPARROWS POINT LLC, as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL STEELTON LLC (formerly ISG
		Steelton LLC), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer

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		ARCELORMITTAL LACKAWANNA LLC (formerly,
		ISG Lackawanna LLC), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL XXXXX HARBOR LLC (formerly, ISG Xxxxx Harbor LLC), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL COLUMBUS LLC (formerly, ISG Columbus Coatings, LLC), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL GEORGETOWN INC. (formerly,
		ISG Georgetown Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		MITTAL STEEL USA – RAILWAYS INC. (formerly,
		ISG Railways Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL HIBBING INC. (formerly, ISG
		Hibbing Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer

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		HIBBING TACONITE HOLDING INC.,
		as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ISG ACQUISITION INC.,
		as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		ARCELORMITTAL REAL ESTATE INC. (formerly
		ISG Real Estate Inc.), as a Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: VP, Finance and Chief Accounting Officer
		ARCELORMITTAL TOW PATH VALLEY BUSINESS
		PARK DEVELOPMENT COMPANY (formerly, Tow
		Path Valley Business Park Development Company), as a
		Guarantor
		By:		/s/ Xxxxxx X. XxXxx Name: Xxxxxx X. XxXxx
				Title: Treasurer
		LASALLE BANK NATIONAL ASSOCIATION,
		as a Trustee
		By:		/s/ Xxxxx X. Xxxxxxx Name: Xxxxx X. Xxxxxxx
				Title: Assistant Vice President

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