# Relationship history for MSHA mine 4402216

Current hierarchy: **Turner Herbert Coal Company → Herbert Turner Coal Company → No 15**

- 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:** Poteet Coal Company → No 15; 1950-01-01 to 1971-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Poteet Rosa → No 15; 1950-01-01 to 1971-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Poteet Rosa → Poteet Coal Company; 1950-01-01 to 1971-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Turner Herbert Coal Company → No 15; 1971-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Herbert Turner Coal Company → No 15; 1972-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Turner Herbert Coal Company → Herbert Turner Coal Company; 1972-01-01 to current/open; source msha-controller-operator-history