# Relationship history for MSHA mine 3300497

Current hierarchy: **Akers Bill & Jerry Massie → Brohard Mining & Development Inc → Pedro Mine & Mill**

- 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

- **operator_operates_mine:** Brohard Mining & Development Inc → Pedro Mine & Mill; 1950-01-01 to 1983-11-01; source msha-controller-operator-history
- **controller_controls_mine:** Brohard C E → Pedro Mine & Mill; 1950-01-01 to 1983-11-01; source msha-controller-operator-history
- **controller_controls_operator:** Brohard C E → Brohard Mining & Development Inc; 1950-01-01 to 1983-11-01; source msha-controller-operator-history
- **operator_operates_mine:** Brohard Mining & Development Inc → Pedro Mine & Mill; 1983-11-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Akers Bill & Jerry Massie → Pedro Mine & Mill; 1983-11-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Akers Bill & Jerry Massie → Brohard Mining & Development Inc; 1983-11-02 to current/open; source msha-controller-operator-history