# Relationship history for MSHA mine 1401323

Current hierarchy: **O'Rourke Dary → Prairie Mining Inc → Plant No 1**

- 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

- **controller_controls_mine:** O'Rourke Brothers Inc → Plant No 1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** J A Tobin Construction Company → Plant No 1; 1979-01-01 to 1985-10-20; source msha-controller-operator-history
- **controller_controls_operator:** O'Rourke Brothers Inc → J A Tobin Construction Company; 1979-01-01 to 1985-10-20; source msha-controller-operator-history
- **operator_operates_mine:** Prairie Mining Inc → Plant No 1; 1985-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** O'Rourke Dary Et Al → Plant No 1; 1985-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** O'Rourke Dary Et Al → Prairie Mining Inc; 1985-10-21 to current/open; source msha-controller-operator-history