| 1 | GCP | DAC Air, S.A. | IATA: 6P, Ceased operations | RO | AVCODES |
| 2 | GCPD | GLENN CO PRODUCE DISTRIBUTORS INC | | | SCAC4 |
| 3 | GCPI | GARFIELD CONTAINER TRANSPORT INC | | | SCAC4 |
| 4 | GCPR | GREAT CONCEPTS INC | | | SCAC4 |
| 5 | GCPU | BURLINGTON NORTHERN AND SANTA FE RAILWAY (BNSF RAILWAY) [GENSTAR CONTAINER CORPORATION] | | | PWRC |
| 6 | GCPU | Genstar (BNSF Railway) | | | RSRV |
| 7 | GCPV | Cementos Portland Valderrivas, S.A. | | ES | VKM |
| 8 | GCPX | Georgia Gulf Corp., PVC Division | added 4/1985; 1/1994-7/2005 | | NAKINA |
| 9 | GCPX | Georgia Pacific Chemicals, Inc. | added 10/1984; eliminated 4/1985 | | NAKINA |
| 10 | GCPX | Georgia Pacific Chemicals, Inc. | added 10/84; eliminated 4/85 | | NRHS |
| 11 | GCPX | Georgia Gulf Corp., PVC Division | added 4/85; 1/94-7/2000 | | NRHS |
| 12 | GCPX | GEORGIA GULF CORP., PVC DIV.[GEORGIA PACIFIC CHEMICALS] | | | PWRC |
| 13 | GCPX | Georgia Gulf Corporation (PVC Division) | | | RSRV |
| 14 | GCPX | GEORGIA GULF CORP., PVC DIV. | | | SCAC4 |
