# Relationship history for MSHA mine 1200331

Current hierarchy: **British Petroleum Company PLC → Old Ben Coal Company → Old Ben 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

- **controller_controls_mine:** British Petroleum Company PLC → Old Ben 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Amax Coal Company → Old Ben 1 Mine; 1950-01-01 to 1978-09-26; source msha-controller-operator-history
- **controller_controls_mine:** Cyprus Amax Minerals Company → Old Ben 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Amax Coal Company; 1950-01-01 to 1978-09-26; source msha-controller-operator-history
- **operator_operates_mine:** Old Ben Coal Company → Old Ben 1 Mine; 1978-09-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** British Petroleum Company PLC → Old Ben Coal Company; 1978-09-27 to current/open; source msha-controller-operator-history