| 1 | GCI | Guarda Costiera Italiana | Callsign: Italian Coast Guard, | I | AVCODES |
| 2 | GCIH | GUGGISBERG CHEESE INC | | | SCAC4 |
| 3 | GCIP | GRUPO CORSA INTERNACIONAL | | | SCAC4 |
| 4 | GCIQ | GROUPE CANAM INC | | | SCAC4 |
| 5 | GCIR | | | IRQ | TRAFFIC |
| 6 | GCIU | GLOBAL CONTAINER AND CHASSIS | | USA | BIC |
| 7 | GCIU | GLOBAL CONTAINER LINES (BAHAMAS) LT | | | SCAC4 |
| 8 | GCIX | Gabriel Chemicals | added 1/1997; eliminated 1/1998; 7/2000-7/2005 (not listed) | | NAKINA |
| 9 | GCIX | Gabriel Chemicals | added 1/97; eliminated 1/98; 7/2000 | | NRHS |
| 10 | GCIX | GABRIEL CHEMICALS, INC. | | | PWRC |
| 11 | GCIX | Gabriel Chemicals | | | RSRV |
