| 1 | EDCX | El Dorado Chemical Co. | added 7/1984; 1/1994-7/2005 | | NAKINA |
| 2 | EDCX | E.D.C., Inc. | added 1/1984; eliminated 7/1984 | | NAKINA |
| 3 | EDCX | Ethyl-Dow Corp. Chemical Co. | 1/1952-10/1966; eliminated 4/1970 | | NAKINA |
| 4 | EDCX | Ethyl-Dow Chemical Co. | 1/1946-1/1950 | | NAKINA |
| 5 | EDCX | Ethyl-Dow Corp. Chemical Co. | 1/52-10/66; eliminated 4/70 | | NRHS |
| 6 | EDCX | E.D.C., Inc. | eliminated 7/84 | | NRHS |
| 7 | EDCX | El Dorado Chemical Co. | added 7/84; 1/94-7/2000 | | NRHS |
| 8 | EDCX | *ETHYL-DOW CHEMICAL CO. | | | PWRC |
| 9 | EDCX | +EL DORADO CHEMICAL COMPANY (EDC, INC.) | | | PWRC |
| 10 | EDCX | EDC | | | RSRV |
| 11 | EDCX | ETHYL-DOW CHEMICAL CO | | | SCAC3 |
| 12 | EDCX | EL DORADO CHEMICAL COMPANY | | | SCAC4 |
