| 1 | ASTX | Asarco LLC | added 10/2008 | | NAKINA |
| 2 | ASTX | Asarco Inc. | added 10/1975; 1/1980-7/2005; eliminated 10/2008 | | NAKINA |
| 3 | ASTX | American Smelting and Refining Co. | added 1/1974; 1/1975; eliminated 10/1975 | | NAKINA |
| 4 | ASTX | American Sheet & Tin Plate Co. | 7/1937 (not listed) | | NAKINA |
| 5 | ASTX | American Sheet & Tin Plate Co. (Carnegie-Illinois Steel Corp.) | 7/1936 | | NAKINA |
| 6 | ASTX | American Sheet & Tin Plate Co. | 7/1930-7/1935; 7/1937 (not listed) | | NAKINA |
| 7 | ASTX | American Smelting and Refining Co. | added 1/74; 1/75 | | NRHS |
| 8 | ASTX | Asarco Inc. | 1/80-7/2000 | | NRHS |
| 9 | ASTX | ASARCO INCORPORATED [AMERICAN SHEET & TIN PLATE CO.; AMERICAN SMELTING & REFINING CO.] | | | PWRC |
| 10 | ASTX | ASARCO | | | RSRV |
| 11 | ASTX | ASARCO LLC | | | SCAC4 |