Subsidiary

State or Country of Incorporation

Adela Investment Company

Chicago Lakeside Development, LLC

Chrome Deposit Corporation

Clairton 1314B Partnership, L.P.

Compagnie de Gestion de Mifergui- Nimba, LTEE

Cygnus Mines Limited

Delaware USS Corporation

Double Eagle Steel Coating Company

Double G Coatings, Inc.

Double G Coatings Company, L.P.

EJ&E West Company

Essex Minerals Company

Feralloy Processing Company

GCW/USS Energy, LLC

Grant Assurance Corporation

Lakeside Land, LLC

La Pointe Iron Company

New Deal Development, Inc.

Obal-Servis, a.s. Košice

Oilfield Technologies, Inc.

Olympic Laser Processing

Orinoco Mining Company

Perdido Land Development, Inc.

PITCAL, Inc.

USS-POSCO Industries

Pitcal Pipe, LLC

United Spiral Pipe, LLC

ProCoil Company, LLC

Smart Screen Systems, Inc.

Societe Des mines de Fer de Guinee Pour L’Exploitation Des Monts Nimba

Steel Health Resources, LLC

Straightline, Inc.

Straightline Source, Inc.

Swan Point Development Company, Inc.

Brookfield Swan Point, LLC

Swan Point Yacht & Country Club, Inc.

Transtar, Inc.

Birmingham Southern Railroad Company

Delray Connecting Railroad Company

Elgin, Joliet and Eastern Railway Company

Fairfield Southern Company, Inc.

Texas & Northern Railway Company

Lake Terminal Railroad Company, The

McKeesport Connecting Railroad Company

Union Railroad Company

Warrior & Gulf Navigation Company

Mobile River Terminal Company

Sisco Stevedoring, LLC

U. S. Steel China, LLC

U. S. Steel International of Canada, LTD.

U. S. Steel Mining Company, LLC

USS Mine Management, Inc.

United States Steel International, Inc.

Compania de Representaciones Mercantiles, Cubacero, S. A.

United States Steel Export Company de Mexico, S.R.L. de C.V.

Acero Prime, S.R.L. de CV

Acero Prime Servicios, S.R.L. de CV

United States Steel International de Mexico, S.R.L. de C. V.

United States Steel Receivables, LLC

U. S. Steel Services s.r.o.

U. S. Steel Timber Company, LLC

USS Galvanizing, Inc.

PRO-TEC Coating Company

PRO-TEC Coating Company, Inc.

USS International Services, LLC

USS Lakeside, LLC

USS Oilwell Supply Co., LTD.

USS Oilwell Tubular, Inc.

USS Portfolio Delaware, Inc.

USS Tubular Processing, Inc.

U. S. Steel Holdings, Inc.

USS Global Holdings I, B.V.

U. S. Steel Košice, s.r.o. (USSK)

Stabilita d.d.s., a.s.

U. S. Steel Kosice – Austria GmbH

Elekroservis VN a VVN a.s.

Hutnictvi železa, a.s.

U. S. Steel Košice – Labortest, s.r.o.

U. S. Steel Kosice – Belgium S.A.

U. S. Steel Kosice Switzerland AG in liquidation

U. S. Steel Košice - Bohemia a.s.

U. S. Steel Kosice - France S.A.

U. S. Steel Košice - SBS, s.r.o.

U. S. Steel Kosice - Germany GmbH

U. S. Steel Kosice (UK) LIMITED

Refrako s.r.o.

Reliningserv s.r.o.

Vulkmont, a.s. Košice

U. S. Steel Global Holdings II, B.V.

U. S. Steel Enterprises BV

U. S. Steel Serbia, d.o.o.

USSB Industrial Business Zone d.o.o.

USSB Kucevo d.o.o.

USSB Spin d.o.o.

USSB Stara Zelezara d.o.o

U. S. Steel Serbia, BV

U. S. Steel Balkan, d.o.o.

U. S. Steel Holdings II, LLC

Worldwide Steel C.V.

U. S. Steel Europe, B.V.

U. S. Steel Holdings IV, Inc.

United States Steel Credit Corporation

UEC Technologies, LLC

Met-Chem Canada, Inc.

Met-Chem, Inc.

UEC Sail Information Technology, LTD.

USX Engineers and Consultants

USX International Sales Company, Inc.

USX Participacoes LTDA.

Merinds Mineracao

Mineracao Carajas, LTDA.

Mineracao Maraba, LTDA.

USX RTI Holdings, Inc.

Republic Technologies International Holdings LLC

Republic Technology International LLC

Worthington Specialty Processing

WP Acquisition Holding Corporation

Preserve Village Developers, LLC

Appleford Swim Club, Inc.

Hillsboro Residential Association, Inc.

Brocks Gap Swim Club, Inc.

Chestnut Ridge Owner’s Association, Inc.

Lake Trace Owner’s Association, Inc.

Oxmoor Corporate Park Association, Inc.

The Preserve Owners Association, Inc.

Rosser Farms Homeowner’s Association, Inc.

U. S. Steel Tubular Products, Inc.

Zinklahoma, Inc.

Fintube Technologies, Inc.

Lone Star Steel Holdings, Inc.

Fintube Canada, Inc.

Star Capital Funding, Inc.

Star Brazil US, LLC1

Star Brazil US, LLC 2, Suite 600

Lone Star Brazil Holdings 1 Ltda.

Lone Star Brazil Holdings 2 Ltda.

Apolo Tubulars S.A.

Star International Holdings Ltd.

Star China Ltd.

Star TC Holdings, LLC

Lone Star Technologies China, LLC

Aletas Y Birlos Mexicana SA, De C.V.

Aletas Y Birlos SA, De C.V.

Fintube (Thailand) Limited

U. S. Steel Canada Limited Partnership

The Steel Company of Canada, Limited

U. S. Steel Canada, Inc.

Stelco Holding Company

Ontario Coal Company

Ontario Eveleth Company

Stelco Coal Company

Chisholm Coal Company

Ontario Hibbing Company

Stelco Erie Corporation

Kanawha Coal Company

Ontario Tilden Company

Tilden Mining Company, LLC

Hibbing Development Company

Hibbing Taconite Company

Beckley Coal Co.

Mathies Coal Co. (PA)

Mittal USA - Ontario Iron Inc.

Hamilton Coke GP Inc.

Hamilton Coke Limited Partnership

Lake Erie Coke GP Inc.

Lake Erie Coke Limited Partnership