# Relationship history for MSHA mine 1513091

Current hierarchy: **Hatton Billy → Briar Coal Company → No 3 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

- **controller_controls_mine:** Hugh  Holbrook → No 3 Mine; 1976-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Holbrook Mining Company Inc → No 3 Mine; 1981-09-01 to 1983-10-02; source msha-controller-operator-history
- **controller_controls_operator:** Hugh  Holbrook → Holbrook Mining Company Inc; 1981-09-01 to 1983-10-02; source msha-controller-operator-history
- **controller_controls_mine:** Hatton Billy Et Al → No 3 Mine; 1983-03-17 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Briar Coal Company → No 3 Mine; 1983-10-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hatton Billy Et Al → Briar Coal Company; 1983-10-03 to current/open; source msha-controller-operator-history