| 1 | MPTX | Procor Ltd. | added 1/1974; 1/1975-7/2005 | | NAKINA |
| 2 | MPTX | Union Tank Car Co. | added 7/1973; eliminated 1/1974 | | NAKINA |
| 3 | MPTX | Magnolia Provision Co. | 8/1920-7/1923 | | NAKINA |
| 4 | MPTX | Union Tank Car Co. | added 7/73; eliminated 1/74 | | NRHS |
| 5 | MPTX | Procor Ltd. | added 1/74; 1/75-7/2000 | | NRHS |
| 6 | MPTX | *MAGNOLIA PROVISION CO. | | | PWRC |
| 7 | MPTX | +(PROX) PROCOR LIMITED [UNION TANK CAR CO.] | | | PWRC |
| 8 | MPTX | Magnolia Provision Co. (Procor) | | | RSRV |
| 9 | MPTX | PROCOR LIMITED | | | SCAC4 |
