# Relationship history for MSHA mine 4501267

Current hierarchy: **Cliff  Schroeder → South Hill Sand & Gravel Company → South Hill 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Haley Bob → South Hill Pit; 1950-01-01 to 1985-07-25; source msha-controller-operator-history
- **operator_operates_mine:** Haley Construction Company → South Hill Pit; 1979-01-01 to 1980-01-03; source msha-controller-operator-history
- **controller_controls_operator:** Haley Bob → Haley Construction Company; 1979-01-01 to 1980-01-03; source msha-controller-operator-history
- **controller_controls_mine:** Mosby Wayne → South Hill Pit; 1979-07-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** M & M Crushing Company Inc → South Hill Pit; 1980-01-04 to 1981-01-06; source msha-controller-operator-history
- **controller_controls_operator:** Mosby Wayne → M & M Crushing Company Inc; 1980-01-04 to 1981-01-06; source msha-controller-operator-history
- **operator_operates_mine:** South Hill Sand & Gravel Company → South Hill Pit; 1981-01-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cliff  Schroeder → South Hill Pit; 1981-01-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cliff  Schroeder → South Hill Sand & Gravel Company; 1981-01-07 to current/open; source msha-controller-operator-history