# Relationship history for MSHA mine 1503790

Current hierarchy: **Hurley Alex → B Z & H 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:** Low Gap Coal Company Inc → No 1 Mine; 1950-01-01 to 1975-03-20; source msha-controller-operator-history
- **controller_controls_mine:** Biliter Marvin Jr → No 1 Mine; 1950-01-01 to 1975-03-20; source msha-controller-operator-history
- **controller_controls_operator:** Biliter Marvin Jr → Low Gap Coal Company Inc; 1950-01-01 to 1975-03-20; source msha-controller-operator-history
- **operator_operates_mine:** B Z & H Coal Corp → No 1 Mine; 1975-03-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hurley Alex → No 1 Mine; 1975-03-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hurley Alex → B Z & H Coal Corp; 1975-03-21 to current/open; source msha-controller-operator-history