# Relationship history for MSHA mine 4002759

Current hierarchy: **Wilkinson John F → W & S Coal Group Inc → Heather Mine**

- 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

- **controller_controls_mine:** Wilkinson John F → Heather Mine; 1981-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** W & S Coal Group Inc → Heather Mine; 1981-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wilkinson John F → W & S Coal Group Inc; 1981-11-01 to current/open; source msha-controller-operator-history