# Relationship history for MSHA mine 4201759

Current hierarchy: **BHP Billiton → Bhp Minerals International Inc → Alton 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:** General Electric Company → Alton Mine; 1950-01-01 to 1984-04-01; source msha-controller-operator-history
- **operator_operates_mine:** Utah International Inc → Alton Mine; 1981-10-01 to 1984-04-01; source msha-controller-operator-history
- **controller_controls_operator:** General Electric Company → Utah International Inc; 1981-10-01 to 1984-04-01; source msha-controller-operator-history
- **operator_operates_mine:** Bhp Minerals International Inc → Alton Mine; 1984-04-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** BHP Billiton → Alton Mine; 1984-04-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** BHP Billiton → Bhp Minerals International Inc; 1984-04-02 to current/open; source msha-controller-operator-history