# Relationship history for MSHA mine 1512153

Current hierarchy: **Wood Haynes R → H R Wood Coal Company Inc → Fern Valley**

- 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:** H R Wood Coal Company Inc → Fern Valley; 1979-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wood Haynes R → Fern Valley; 1979-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wood Haynes R → H R Wood Coal Company Inc; 1979-11-01 to current/open; source msha-controller-operator-history