# Relationship history for MSHA mine 1509815

Current hierarchy: **Mountain Coals Inc → Buckhorn Mining Corp → Breathitt #1 Surface**

- 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

- **controller_controls_mine:** Mountain Coals Inc → Breathitt #1 Surface; 1974-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Buckhorn Mining Corp → Breathitt #1 Surface; 1976-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mountain Coals Inc → Buckhorn Mining Corp; 1976-07-01 to current/open; source msha-controller-operator-history