# Relationship history for MSHA mine 1202122

Current hierarchy: **Romero Richard → Northern Coal Company Inc → Owen 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

- **operator_operates_mine:** Northern Coal Company Inc → Owen Mine; 1992-07-01 to 1992-10-14; source msha-controller-operator-history
- **controller_controls_mine:** Francis William → Owen Mine; 1992-07-01 to 1993-03-17; source msha-controller-operator-history
- **controller_controls_operator:** Francis William → Northern Coal Company Inc; 1992-07-01 to 1992-10-14; source msha-controller-operator-history
- **operator_operates_mine:** Shamrock Mining Company Inc → Owen Mine; 1992-10-15 to 1993-05-09; source msha-controller-operator-history
- **controller_controls_mine:** La Follette Mary Ann → Owen Mine; 1992-10-15 to 1993-05-09; source msha-controller-operator-history
- **controller_controls_operator:** La Follette Mary Ann → Shamrock Mining Company Inc; 1992-10-15 to 1993-05-09; source msha-controller-operator-history
- **controller_controls_mine:** Romero Richard → Owen Mine; 1993-02-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Northern Coal Company Inc → Owen Mine; 1993-05-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Romero Richard → Northern Coal Company Inc; 1993-05-10 to current/open; source msha-controller-operator-history