# Relationship history for MSHA mine 4001738

Current hierarchy: **Duncan Roger J → D & D Coal Company → J J #1 Section 2**

- 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

- **operator_operates_mine:** H & B Coal Company → J J #1 Section 2; 1974-12-01 to 1975-11-09; source msha-controller-operator-history
- **controller_controls_mine:** H & B Coal Company → J J #1 Section 2; 1974-12-01 to 1975-11-09; source msha-controller-operator-history
- **controller_controls_operator:** H & B Coal Company → H & B Coal Company; 1974-12-01 to 1975-11-09; source msha-controller-operator-history
- **operator_operates_mine:** Braden Coal Company → J J #1 Section 2; 1975-11-10 to 1976-03-11; source msha-controller-operator-history
- **controller_controls_mine:** Braden Calvin → J J #1 Section 2; 1975-11-10 to 1976-03-11; source msha-controller-operator-history
- **controller_controls_operator:** Braden Calvin → Braden Coal Company; 1975-11-10 to 1976-03-11; source msha-controller-operator-history
- **operator_operates_mine:** Taylor Coal Company → J J #1 Section 2; 1976-03-12 to 1978-02-09; source msha-controller-operator-history
- **controller_controls_mine:** Taylor Roy C & Mike → J J #1 Section 2; 1976-03-12 to 1978-02-09; source msha-controller-operator-history
- **controller_controls_operator:** Taylor Roy C & Mike → Taylor Coal Company; 1976-03-12 to 1978-02-09; source msha-controller-operator-history
- **operator_operates_mine:** Brumco Company → J J #1 Section 2; 1978-02-10 to 1981-03-22; source msha-controller-operator-history
- **controller_controls_mine:** Brummett Lillian & Clyde → J J #1 Section 2; 1978-02-10 to 1981-03-22; source msha-controller-operator-history
- **controller_controls_operator:** Brummett Lillian & Clyde → Brumco Company; 1978-02-10 to 1981-03-22; source msha-controller-operator-history
- **operator_operates_mine:** D & D Coal Company → J J #1 Section 2; 1981-03-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Duncan Roger J → J J #1 Section 2; 1981-03-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Duncan Roger J → D & D Coal Company; 1981-03-23 to current/open; source msha-controller-operator-history