Exhibit 21

UNITED STATES STEEL CORPORATION
SUBSIDIARIES AND JOINT VENTURES AS OF DECEMBER 31, 2013

Company Name
Chisholm Coal LLC
Chrome Deposit Corporation
Compagnie de Gestion de Mifergui- Nimba, LTEE
Cygnus Mines Limited
Double Eagle Steel Coating Company
Double G Coatings, Inc.
Double G Coatings Company, L.P.
Essex Minerals Company
Feralloy Processing Company
GCW/USS Energy, LLC
Grant Assurance Corporation
Kanawha Coal LLC
Oilfield Technologies, Inc.
Orinoco Mining Company
PITCAL, Inc.
	USS-POSCO Industries
Perdido Land Development, Inc.
Pitcal Pipe, LLC
Preserve Village Developers, LLC
Steel Health Resources, LLC
Stelco Holding Company
	Ontario Coal Company
	Ontario Eveleth Company
	Ontario Hibbing Company
	Stelco Coal Company
		Stelco Erie Corporation
		Ontario Tilden Company
Swan Point Yacht & Country Club, Inc.
	SPDC Hotel, LLC
	Swan Point Development Company, Inc.
		Brookfield Swan Point, LLC
Timber Wolf Land, LLC
Transtar, Inc.
	Delray Connecting Railroad Company
	Gary Railway Company
	Tracks Traffic and Management Services, Inc.
	Texas & Northern Railway Company
	Lake Terminal Railroad Company, The
		Lorain Northern Company f/k/a/ Ohio Northern Company
	Union Railroad Company
	Birmingham Southern Railroad Company
		Fairfield Southern Company, Inc.
		Warrior & Gulf Navigation LLC
U. S. Steel China, LLC
U. S. Steel Holdings, Inc.
	U. S. Steel Holdings II, LLC

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UNITED STATES STEEL CORPORATION
SUBSIDIARIES AND JOINT VENTURES AS OF DECEMBER 31, 2013
(continued)

Company Name

	Worldwide Steel C.V.
			U. S. Steel Global Holdings I B.V.
				U. S. Steel Košice, s.r.o. (USSK)
					OBAL-SERVIS, a.s. Košice
						U. S. Steel Europe (UK) Limited
					U. S. Steel Košice – Labortest, s.r.o.
					U. S. Steel Services s.r.o.
					U. S. Steel Europe - Bohemia a.s.
					U. S. Steel Europe - France S.A.
					U.S. Steel Košice - SBS, s.r.o.
					U. S. Steel Europe - Germany GmbH
					U. S. Steel Europe - Italy S.r.l.
					RMS, a.s. Košice (prev.VULKMONT, a.s. Košice)
				U. S. Steel Enterprises BV
				U. S. Steel Global Holdings II, B.V.
				U. S. Steel Canada Limited Partnership
					U. S. Steel Canada Inc.
						The Steel Company of Canada, Limited
						4347226 Canada Inc.
						The Stelco Plate Company Ltd.
						U. S. Steel Tubular Products Canada GP Inc.
							U. S. Steel Tubular Products Canada Limited Partnership
						742784 Ontario Inc.
						Baycoat Limited
						Baycoat Limited Partnership (Baycoat L.P.)
						D.C. Chrome Limited
		U. S. Steel Serbia, BV
	U. S. Steel Holdings IV, Inc.
U. S. Steel International of Canada, LTD.
U. S. Steel Mining Company, LLC
U. S. Steel Receivables LLC
U. S. Steel Timber Company, LLC
U. S. Steel Tubular Products, Inc.
	U. S. Steel Oilwell Services, LLC
		Patriot Premium Threading Services, LLC
	U.S. Steel Produtos Tubulares do Brasil Ldta.
	Zinklahoma, Inc.
	Star Brazil US, LLC 2
	Star Brazil US, LLC1
		Lone Star Brazil Holdings 1 Ltda.
			Lone Star Brazil Holdings 2 Ltda.
				Apolo Tubulars S.A.
	Lone Star Steel Holdings, Inc.
		Lone Star Steel Holdings II, Inc.
			Fintube (Thailand) Limited
UEC Technologies, LLC
	Met-Chem Canada, Inc.
		Met-Chem, Inc.
	USX Engineers and Consultants

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UNITED STATES STEEL CORPORATION
SUBSIDIARIES AND JOINT VENTURES AS OF DECEMBER 31, 2013
(continued)

Company Name

	UEC Sail Information Technology, LTD.
United States Steel International, Inc.
	United States Steel Export Company de Mexico, S.R.L. de C.V.
		Acero Prime Servicios, S.R.L. de CV
	United States Steel International de Mexico, S.R.L. de C. V.
USS Galvanizing, Inc.
	PRO-TEC Coating Company
		PRO-TEC Coating Company, Inc.
USS International Services, LLC
USS Lakeside, LLC
	Chicago Lakeside Development, LLC
USS Mine Management, Inc.
USS Oilwell Supply Co., LTD.
USS Oilwell Tubular, Inc.
USS Portfolio Delaware, Inc.
USS WSP, LLC
	Worthington Specialty Processing
		ProCoil Company, LLC
		Worthington Taylor, LLC
USX International Sales Company, Inc.