# Relationship history for MSHA mine 1507092

Current hierarchy: **Ronald S  Ratliff → R S Mining Inc → Rsno3**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Johnson Ralph → Rsno3; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Johnson Coal Company Inc → Rsno3; 1974-05-24 to 1987-10-18; source msha-controller-operator-history
- **controller_controls_operator:** Johnson Ralph → Johnson Coal Company Inc; 1974-05-24 to 1987-10-18; source msha-controller-operator-history
- **controller_controls_mine:** Watts Marvin → Rsno3; 1987-08-20 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ampak Mining Inc → Rsno3; 1987-10-19 to 1988-07-17; source msha-controller-operator-history
- **controller_controls_mine:** Kretzer Peggy A → Rsno3; 1987-10-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kretzer Peggy A → Ampak Mining Inc; 1987-10-19 to 1988-07-17; source msha-controller-operator-history
- **controller_controls_mine:** Ronald S  Ratliff → Rsno3; 1988-07-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southern Hills Mining Company Inc → Rsno3; 1988-07-18 to 1989-03-07; source msha-controller-operator-history
- **controller_controls_operator:** Watts Marvin → Southern Hills Mining Company Inc; 1988-07-18 to 1989-03-07; source msha-controller-operator-history
- **operator_operates_mine:** R S Mining Inc → Rsno3; 1989-03-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronald S  Ratliff → R S Mining Inc; 1989-03-08 to current/open; source msha-controller-operator-history