Subsidiary

Adela Investment Company S.A.

Chrome Deposit Corporation

Clairton 1314B Partnership, L.P.

Compagnie de Gestion de Mifergui-Nimba, LTEE.

Cygnus Mines Limited

Delaware USS Corporation

Delray Connecting Railroad

Double Eagle Steel Coating Company

Double G Coatings, Inc.

Double G Coatings Company, L.P.

Essex Minerals Company (Societe des Mineraux Essex)

Farms Sewer Company, Inc.

Farms Water Company, Inc.

Feralloy Processing Co.

Grant Assurance Corporation

La Pointe Iron Company

New Deal Development, Inc.

New King Court Development Associates, LLC

Oilfield Technologies, Inc.

Olympic Laser Processing

Orinoco Mining Company

Pasadena Yacht and Country Club, Inc.

Perdido Land Development Co., Inc.

Phil Prop, Inc.

PITCAL, Inc.

USS-POSCO Industries

ProCoil Company, LLC

Smart Screen Systems, Inc.

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

Straightline Source, Inc.

Straightline, Inc.

Swan Point Yacht & Country Club, Inc.

Tilden Iron Mining Company

Transtar, Inc.

Birmingham Southern Railroad Company

Elgin, Joliet and Eastern Railway Company

Fairfield Southern Company, Inc.

Lake Terminal Railroad Company, The

McKeesport Connecting Railroad Company

Tracks Traffic and Management Services, Inc.

Union Railroad Company

Warrior & Gulf Navigation Company

Mobile River Terminal Company

Sisco Stevedoring, LLC

The Southern International Services Company, Inc.

The Southern International Services Company II, Inc.

Transtar Logistics, LLC

EX-IM Logistics, 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 C.V.

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

U. S. Steel Receivables, LLC

U. S. Steel Timber Company, LLC

USS Coal Sales, LLC

USS Galvanizing, Inc.

PRO-TEC Coating Company

PRO-TEC Coating Company, Inc.

USS International Services, 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 Kosice (USSK)

Elektroservis VN a VVN a.s. Kosice

Energoservis a.s. Kosice

Hutnictvi zeleza (Czech Republic)

International Trade Center a.s.

NV Promet SA (Belgium)

SZ Stahl GmbH (Germany)

Waltzwerke Finow GmbH

Betrieber Gesellschaft Nordbahn GmbH

Stawa Stahlbau GmbH

Vozmult a.s. Kosice

VSZ (U.K.) Ltd. (United Kingdom)

Vulkmont a.s. Kosice

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

U. S. Steel Serbia, B.V.

Sartid, a.d.

Sartid Beli Limovi, a.d.

Luka Smedervo d.o.o.

Veljko Dugosevic d.o.o. Kucevo

Spin d.o.o.

Slobodna Zona Smederevo

Stara Zelezara d.o.o. Smederevo

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

U. S. Steel Holdings III, Inc.

U. S. Steel Poland, B.V.

U. S. Steel Europe, B.V.

USX Credit Corp. – California

UEC Technologies, LLC

Met-Chem Canada Inc.

UEC Sail Information Technology, LTD.

USX Engineers and Consultants, Inc.

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 Technologies International LLC

Worthington Specialty Processing