Reporting mark

A reporting mark is a code used to identify owners or lessees of rolling stock and other equipment used on certain rail transport networks.

The code typically reflects the name or identifying number of the owner, lessee, or operator of the equipment, similar to IATA airline designators.

In North America, the mark, which consists of an alphabetic code of two to four letters, is stenciled on each piece of equipment, along with a one- to six-digit number.

The Association of American Railroads (AAR) assigns marks to all carriers, under authority granted by the U.S.

Railinc, a subsidiary of the AAR, maintains the active reporting marks for the North American rail industry.

Private (non-common carrier) freight car owners in Mexico were issued, up until around 1990, reporting marks ending in two X's, possibly to signify that their cars followed different regulations (such as bans on friction bearing trucks) than their American counterparts and so their viability for interchange service was impaired.

Companies owning trailers used in trailer-on-flatcar service are assigned marks ending with the letter "Z", and the National Motor Freight Traffic Association, which maintains the list of Standard Carrier Alpha Codes, assigns marks ending in "U" to owners of intermodal containers.

CMO originally belonged to Chicago, St. Paul, Minneapolis and Omaha Railway, a predecessor of the CNW, from which the UP inherited it.

The registered keeper of a vehicle is now indicated by a separate Vehicle Keeper Marking (VKM), usually the name of the owning company or an abbreviation thereof, which must be registered with the Intergovernmental Organisation for International Carriage by Rail (OTIF) and the European Union Agency for Railways (ERA)[3] and which is unique throughout Europe and parts of Asia and Northern Africa.