| 1 | UNCX | United Central Oil Corp. (Crown Central Petroleum Corp.) | 7/1930 | | NAKINA |
| 2 | UNCX | Universal Car Co. | 7/1935-4/1938 | | NAKINA |
| 3 | UNCX | Union Carbide Canada Ltd., Plastics & Chemicals | added 7/1981; eliminated 4/1987 | | NAKINA |
| 4 | UNCX | General Electric Railcar Services Corp. | eliminated 4/1992 | | NAKINA |
| 5 | UNCX | CGTX, Inc. | added 4/1992; 1/1994-7/2000; eliminated 4/2002 | | NAKINA |
| 6 | UNCX | GATX Rail Canada Corp. | added 4/2002; 7/2005 | | NAKINA |
| 7 | UNCX | Universal Car Co. | Apr-38 | | NRHS |
| 8 | UNCX | Union Carbide Canada Ltd., Plastics & Chemicals | added 7/81; eliminated 4/87 | | NRHS |
| 9 | UNCX | General Electric Railcar Services Corp. | eliminated 4/92 | | NRHS |
| 10 | UNCX | CGTX, Inc. | added 4/92; 1/94-7/2000 | | NRHS |
| 11 | UNCX | *CROWN CENTRAL PETROLEUM CO. [UNITED CENTRAL OIL CORP.] | | | PWRC |
| 12 | UNCX | *UNIVERSAL CAR CO. | | | PWRC |
| 13 | UNCX | *UNION CARBIDE CANADE, LTD. | | | PWRC |
| 14 | UNCX | +GATX RAIL CANADA CORP. [(CGTX)GENERAL ELECTRIC RAILCAR SERVICES CORP.] | | | PWRC |
| 15 | UNCX | Union Carbide Canada | | | RSRV |
| 16 | UNCX | GATX RAIL CANADA CORPORATION | | | SCAC4 |
