# Relationship history for MSHA mine 1509644

Current hierarchy: **Mc Gaw John Scott → Dawn Coal Company → Heath No 3 Strip**

- 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:** Dawn Coal Company → Heath No 3 Strip; 1976-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Gaw John Scott → Heath No 3 Strip; 1976-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Gaw John Scott → Dawn Coal Company; 1976-03-01 to current/open; source msha-controller-operator-history