| 1 | IPC | Intercontinental Pacific Airways, Inc. | IATA: IS, Callsign: Interpac, IATA designator changed to IO | RP | AVCODES |
| 2 | IPC | Intercontinental Pacific Airways, Inc. | IATA: IO, Callsign: Interpac, IATA designator changed from IS* | RP | AVCODES |
| 3 | IPCI | INTERNATIONAL PAPER CO ( INTERMODAL | | | SCAC4 |
| 4 | IPCM | INTERDOM PARTNERS LLC | | | SCAC4 |
| 5 | IPCT | ISC SHIPPING | | | SCAC4 |
| 6 | IPCU | INDEPENDENT CONTAINER LINE | | | PWRC |
| 7 | IPCU | Independent Container Line | | | RSRV |
| 8 | IPCU | INLET PETROLEUM COMPANY | | | SCAC4 |
| 9 | IPCX | International Paper Co. | 8/1920-1/1980; eliminated 10/1981; added 10/1984; 1/1994-7/2005 | | NAKINA |
| 10 | IPCX | International Paper Co. | 4/38-1/80; eliminated 10/81; added 10/84; 1/94-7/2000 | | NRHS |
| 11 | IPCX | INTERNATIONAL PAPER COMPANY | | | PWRC |
| 12 | IPCX | International Paper | | | RSRV |
| 13 | IPCX | INTERNATIONAL PAPER COMPANY | | | SCAC4 |
| 14 | IPCZ | INTERNATIONAL PAPER CO. | | | PWRC |
