| 1 | WMCX | The Westinghouse Machine Co. | 8/1920 | | NAKINA |
| 2 | WMCX | The Westinghouse Machine Co. (Westinghouse Electric & Manufacturing Co.—Machine Works) | 7/1923 | | NAKINA |
| 3 | WMCX | L.H. Wentz (Oil Division) | 7/1935 | | NAKINA |
| 4 | WMCX | Williams Molasses Co. | 4/1947-1/1950 | | NAKINA |
| 5 | WMCX | *WESTINGHOUSE ELECTRIC & MFG. CO, MACHINE WORKS [WESTINGHOUSE MACHINE CO.] | | | PWRC |
| 6 | WMCX | *WILLIAMS MOLASSES CO. | | | PWRC |
| 7 | WMCX | Westmoreland Coal Company | | USA | TRAFFIC |
