# Relationship history for MSHA mine 2200496

Current hierarchy: **Cook William G Jr → C & F Contracting Company Inc → Williams Pit**

- 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:** Phillips W R (Billy) → Williams Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Contractors Gravel Company Inc → Williams Pit; 1979-01-01 to 1983-01-05; source msha-controller-operator-history
- **controller_controls_operator:** Phillips W R (Billy) → Contractors Gravel Company Inc; 1979-01-01 to 1983-01-05; source msha-controller-operator-history
- **controller_controls_mine:** Cook William G Jr → Williams Pit; 1981-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** C & F Contracting Company Inc → Williams Pit; 1983-01-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cook William G Jr → C & F Contracting Company Inc; 1983-01-06 to current/open; source msha-controller-operator-history