| 1 | WCMX | Western Chemical Manufacturing Co. (General Chemical Co.) | 8/1920 | | NAKINA |
| 2 | WCMX | West End Chemical Co. | 1/1952 | | NAKINA |
| 3 | WCMX | Wyandotte Chemicals Corp. | added 4/1959; 4/1961; eliminated 1/1963; added 10/1963; 7/1965-4/1970; eliminated 7/1971 | | NAKINA |
| 4 | WCMX | West End Chemical Co. | Jan-52 | | NRHS |
| 5 | WCMX | Wyandotte Chemicals Corp. | 4/61-4/70 | | NRHS |
| 6 | WCMX | WYANDOTTE CHEMICALS CORP. [WEST END CHEMICAL CO.; GENERAL CHEMICAL CO.; WESTERN CHEMICAL MFG. CO.] | | | PWRC |
