# Relationship history for MSHA mine 4401635

Current hierarchy: **Horn Bill E → Brent Coal Corp → No 1 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

- **operator_operates_mine:** Wanda Coal Company Inc → No 1 Mine; 1950-01-01 to 1982-10-14; source msha-controller-operator-history
- **controller_controls_mine:** Brown Arthur & Walter → No 1 Mine; 1950-01-01 to 1982-10-14; source msha-controller-operator-history
- **controller_controls_operator:** Brown Arthur & Walter → Wanda Coal Company Inc; 1950-01-01 to 1982-10-14; source msha-controller-operator-history
- **operator_operates_mine:** Brent Coal Corp → No 1 Mine; 1982-10-15 to 1983-09-15; source msha-controller-operator-history
- **controller_controls_mine:** Colley Eric R → No 1 Mine; 1982-10-15 to 1983-09-15; source msha-controller-operator-history
- **controller_controls_operator:** Colley Eric R → Brent Coal Corp; 1982-10-15 to 1983-09-15; source msha-controller-operator-history
- **operator_operates_mine:** Brent Coal Corp → No 1 Mine; 1983-09-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Horn Bill E → No 1 Mine; 1983-09-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Horn Bill E → Brent Coal Corp; 1983-09-16 to current/open; source msha-controller-operator-history