| 1 | RSO | Aero Asia International (Private) Ltd. | IATA: E4, Callsign: Aero Asia, IATA Prefix: 532, | PK | AVCODES |
| 2 | RSO | Aero Asia International | IATA: E4 | | ICAO1 |
| 3 | RSOA | R S OIL CORPORATION | | | SCAC4 |
| 4 | RSOC | RSO INC | | | SCAC3 |
| 5 | RSOD | RESOURCE DISTRIBUTION INC | | | SCAC3 |
| 6 | RSOG | RUSSOM TRUCKING INC | | | SCAC4 |
| 7 | RSOI | RIVERSIDE OIL INC | | | SCAC3 |
| 8 | RSOL | RESEARCH SOLVENTS AND CHEMICALS INC | | | SCAC4 |
| 9 | RSOM | ROSS OIL CO INC | | | SCAC4 |
| 10 | RSOP | ROSE OF SHARON TRANSPORTATION LLC | | | SCAC4 |
| 11 | RSOR | Riceboro Southern Ry., LLC | added 1/2005; 7/2005; eliminated 7/2006 | | NAKINA |
| 12 | RSOR | RICEBORO SOUTHERN RAILWAY | | | PWRC |
| 13 | RSOR | Riceboro Southern Railway | | | RSRV |
| 14 | RSOR | RICEBORO SOUTHERN RAILWAY LLC | | | SCAC4 |
| 15 | RSOT | RUSSO TRUCKING INC | | | SCAC4 |
| 16 | RSOX | General Electric Rail Services Corp. | added 10/2001; 7/2005 | | NAKINA |
| 17 | RSOX | Resolution Performance Products | added 4/2001; eliminated 10/2001 | | NAKINA |
| 18 | RSOX | Shell Epoxy Resins | added 1/2001; eliminated 4/2001 | | NAKINA |
| 19 | RSOX | Shell Epoxy Resins | added 1/2001; eliminated 4/2001 | | NRHS |
| 20 | RSOX | Resolution Performance Products | added 4/2001 | | NRHS |
| 21 | RSOX | *RESOLUTION PERFORMANCE PRODUCTS [SHELL EPOXY RESINS] | | | PWRC |
| 22 | RSOX | +GENERAL ELECTRIC RAIL SERVICES CORP.) | | | PWRC |
| 23 | RSOX | General Electric Rail Services Corporation | | | RSRV |
| 24 | RSOX | GENERAL ELECTRIC RAILCAR SERVICES C | | | SCAC4 |
