# Relationship history for MSHA mine 1502472

Current hierarchy: **Thornsberry Garry K & George M Smith → S & T Coal Company → No 9-C**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Southern Mining Company Inc → No 9-C; 1950-01-01 to 1977-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Johnson Donald T → No 9-C; 1950-01-01 to 1977-07-10; source msha-controller-operator-history
- **controller_controls_operator:** Johnson Donald T → Southern Mining Company Inc; 1950-01-01 to 1977-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Murphy Howard → No 9-C; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thornsberry Garry K & George M Smith → No 9-C; 1975-09-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southern Elkhorn Coal Corp → No 9-C; 1977-07-11 to 1979-09-20; source msha-controller-operator-history
- **controller_controls_mine:** International Minerals & Chemical Corp → No 9-C; 1977-07-11 to 1983-04-02; source msha-controller-operator-history
- **controller_controls_operator:** International Minerals & Chemical Corp → Southern Elkhorn Coal Corp; 1977-07-11 to 1979-09-20; source msha-controller-operator-history
- **operator_operates_mine:** Justice & Murphy Coal Company Inc → No 9-C; 1979-09-21 to 1980-08-04; source msha-controller-operator-history
- **controller_controls_operator:** Murphy Howard → Justice & Murphy Coal Company Inc; 1979-09-21 to 1980-08-04; source msha-controller-operator-history
- **operator_operates_mine:** S & T Coal Company → No 9-C; 1980-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thornsberry Garry K & George M Smith → S & T Coal Company; 1980-08-05 to current/open; source msha-controller-operator-history