# Relationship history for MSHA mine 1502121

Current hierarchy: **Inspiration Resources Corporation → Sovereign Coal Corp → No 1-A**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Sovereign Coal Corp → No 1-A; 1950-01-01 to 1981-07-14; source msha-controller-operator-history
- **controller_controls_mine:** Walker George F → No 1-A; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walker George F → Sovereign Coal Corp; 1950-01-01 to 1981-07-14; source msha-controller-operator-history
- **operator_operates_mine:** Sovereign Coal Corp → No 1-A; 1981-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Inspiration Resources Corporation → No 1-A; 1981-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Inspiration Resources Corporation → Sovereign Coal Corp; 1981-07-15 to current/open; source msha-controller-operator-history