List of reporting marks: O

Note: Marks ending in U are for container owners; marks ending in X are not common carriers; marks ending in Z are for trailers without flanged wheels. All other marks are of common-carrier railroads.

O

OACX - Central Transportation, Inc.
OAR - Old Augusta Railroad
OCCU - ATS Container Leasing SA
OCCX - Occidental Chemical Company
OCE - Oregon, California and Eastern Railway
OCEU - Oceanex Inc.
OCFX - Owens Corning Fiberglass
OCLU - Overseas Containers, Ltd.
OCNU - Ocean Lines, Inc.
OCPX - Occidental Chemical Company; Oxy Vinyls
OCR - Oklahoma Central Railroad
OCRR - Ottawa Central Railway
OCRX - Oil Creek Refining Company
OCSU - Scripps Institute of Oceanography
OCTL - Oil Creek and Titusville Lines
OCTR - Octoraro Railway
OCTX - Octel America, Inc.
ODTX - Oil-Dri Corporation of America
OEDX - Ohio Edison Company
OERX - Southern California Railway Museum
OFCX - Ortner Freight Car Company
OFOX - Residco
OFSX - Tucson Electric Power Company
OGEE - Ogeechee Railway
OGEX - Oklahoma Gas and Electric Company
OGSX - Iowa Southern Utilities Company
OHCR - Ohio Central Railroad
OHFX - Fluor Daniel Fernald
OHIC - Ohi-Rail Corporation
OHIO - Ohio Terminal Railway
OHKU - Ohka American, Inc.
OHOX - United States Department of Energy (Ohio Field)
OHPA - Ohio and Pennsylvania Railroad
OHRY - Owego and Harford Railway
OILX - GE Rail Services
OJGX - Oscar J. Glover
OJTX - Tauber Transportation Company
OKAN - Okanagan Valley Railway (OmniTRAX)
OKCE - Okarche Central Railway
OKCX - Lone Star Industries
OKKT - Oklahoma, Kansas and Texas Railroad; Union Pacific Railroad
OLAU - Occidental Chemical Corporation
OLB - Omaha, Lincoln and Beatrice Railway
OLDX - Old Line Holding Company, Inc.
OLGX - Ineos Oligomers USA, LLC
OLLU - Ocean Leasing, Ltd.
OLNX - Olin Corporation
OLO - Ontario L'Orignal Railway
OLYR - Olympic Railroad
OLYU - Olympic Container Corporation
OLYR - Olympic Railroad
OLYX - Olympia Petroleum, Inc.
OLYZ - Showa Line, Ltd.
OMAX - Omaha Public Power District
OMID - Ontario Midland Railroad
OMLP - Ohio Midland Light and Power
OMLX - OmniTRAX Leasing, Ltd.
OMNX - Omnisource; Steel Dynamics.
OMRX - Ozark Mountain Railcar
OMSX - Ohio Mulch; J. T. Leasing, Inc.
ONCT - Ontario Central Railroad
ONER - Ontario Eastern Railroad
ONRR - Ohio and National Railway Company
ONSX - Oglebay Norton Industrial Sands, Inc.
ONT - Ontario Northland Railway
ONTA - Ontario Northland Railway
ONTX - On-Track Railcar Services, Inc.
ONW - Oregon and Northwestern Railroad
ONYX - American Colloid Company
OOCZ - Orient Overseas Line, Inc.
OOLU - OOCL
OOOX - Osborne, Inc.
OOUU - Orient Overseas Line, Inc.
OPE - Oregon, Pacific and Eastern Railway
OPIX - Equistar Chemicals
OPPX - Omaha Public Power District
OPR - Oregon Pacific Railroad
OPSU - EMP
OPSX - Public Service Company of Oklahoma
OPT - Orange Port Terminal Railway
OPX - Ohio Power Company
OR - Owasco River Railway
ORA - Ormet Railroad
ORCU - BSL Transport
OREX - Oregon Department of Agriculture
OROX - United States Department of Energy (Oak Ridge Operations Office)
ORR - Osage Railroad
OSCZ - Intermodal Services, Inc.
OSL - Oregon Short Line; Union Pacific Railroad
OSRX - Ontario Southland Railway
OSSU - Eurovos B.V.
OTCO - Owensville Terminal Company
OTCR - Oakdale Traction Corporation
OTDX - Greenbrier Leasing Corporation
OTPX - Otter Tail Power Company
OTR - Oakland Terminal Railway
OTRX - On-Track Railway Services, Ltd.
OTSX - On-Track Railway Services, Ltd.
OTT - Ottumwa Terminal Railroad
OTTX - TTX Corporation
OTVR - Otter Tail Valley Railroad (RailAmerica)
OUCH - Ouachita Railroad
OUCX - Orlando Utilities Commission
OURD - Ogden Union Railway and Depot Company
OVEX - Ohio Valley Electric Company
OVNZ - Overnite Transportation Company
OVO - Ottawa Valley Railway
OVR - Ohio Valley Railroad
OWIX - Old World Transportation, Ltd.
OWLU - Ocean World Lines, Inc.
OWSX - Oil Well Supply Company
OWTX - Shamrock Coal Company
OXYU - Eurotainer US, Inc.