# Relationship history for MSHA mine 4300416

Current hierarchy: **Stanyon Harold L → Stanyon Slate Products → Stanyon Slate Products**

- 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:** B W Hill Slate Company → Stanyon Slate Products; 1987-09-01 to 1988-08-30; source msha-controller-operator-history
- **controller_controls_mine:** Hill Bedford W → Stanyon Slate Products; 1987-09-01 to 1988-08-30; source msha-controller-operator-history
- **controller_controls_operator:** Hill Bedford W → B W Hill Slate Company; 1987-09-01 to 1988-08-30; source msha-controller-operator-history
- **operator_operates_mine:** Stanyon Slate Products → Stanyon Slate Products; 1988-08-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stanyon Harold L → Stanyon Slate Products; 1988-08-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stanyon Harold L → Stanyon Slate Products; 1988-08-31 to current/open; source msha-controller-operator-history