# Relationship history for MSHA mine 1509515

Current hierarchy: **Branham Greg → B & B Coal Company → 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** R & L Coal Company → No 1 Mine; 1976-02-01 to 1980-11-19; source msha-controller-operator-history
- **controller_controls_mine:** Elliot Ronald Lee → No 1 Mine; 1976-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Elliot Ronald Lee → R & L Coal Company; 1976-02-01 to 1980-11-19; source msha-controller-operator-history
- **operator_operates_mine:** B & B Coal Company → No 1 Mine; 1980-11-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Branham Greg → No 1 Mine; 1980-11-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Branham Greg → B & B Coal Company; 1980-11-20 to current/open; source msha-controller-operator-history