Ownership History
| DMYTROW JR, RONALD S; DMYTROW, SHANNON M | $1 | | 2911-2002 | 06/25/2025 |
| BLEW, THOMAS L; DMYTROW, RONALD S | $1 | | 2495-2210 | 12/03/2013 |
| BLEW, THOMAS L; DMYTROW, RONALD S | $1 | | 2479-0865 | 07/31/2013 |
| BLEW, THOMAS L; DMYTROW, R S | $0 | | 1421-0538 | 01/18/1989 |
| KETCHLEDGE, R III & N I | $0 | | 1240-0813 | 06/17/1977 |
| GENERAL REFRACTORIES CO | $0 | | 0907-0407 | 09/21/1955 |