# Relationship history for MSHA mine 1507736

Current hierarchy: **Whitten Keith R → Right Fork Fuel Company Inc → No 4 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Reynolds Billy Joe--P J Hurley & Charles Dixon → No 4 Mine; 1974-05-13 to 1975-08-20; source msha-controller-operator-history
- **operator_operates_mine:** Right Fork Fuel Company Inc → No 4 Mine; 1974-11-24 to 1975-08-20; source msha-controller-operator-history
- **controller_controls_operator:** Reynolds Billy Joe--P J Hurley & Charles Dixon → Right Fork Fuel Company Inc; 1974-11-24 to 1975-08-20; source msha-controller-operator-history
- **operator_operates_mine:** Right Fork Fuel Company Inc → No 4 Mine; 1975-08-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Whitten Keith R → No 4 Mine; 1975-08-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Whitten Keith R → Right Fork Fuel Company Inc; 1975-08-21 to current/open; source msha-controller-operator-history