# Relationship history for MSHA mine 1517873

Current hierarchy: **Horizon Natural Resources Incorporated → Sunny Ridge Mining Company Inc → No 12-A**

- 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:** John M  Potter et al → No 12-A; 1987-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sunny Ridge Mining Company Inc → No 12-A; 1996-11-01 to 2000-07-19; source msha-controller-operator-history
- **controller_controls_operator:** John M  Potter et al → Sunny Ridge Mining Company Inc; 1996-11-01 to 2000-07-19; source msha-controller-operator-history
- **controller_controls_operator:** Thomas A  Potter et al → Sunny Ridge Mining Company Inc; 1996-11-01 to 2000-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Horizon Natural Resources Incorporated → No 12-A; 1999-06-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sunny Ridge Mining Company Inc → No 12-A; 2000-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Horizon Natural Resources Incorporated → Sunny Ridge Mining Company Inc; 2000-07-20 to current/open; source msha-controller-operator-history