# Relationship history for MSHA mine 0300737

Current hierarchy: **Bowie Jack → Overland Mining Company → Overland 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 Johnson Construction & Coal Company → Overland No 1 Mine; 1950-01-01 to 1974-12-30; source msha-controller-operator-history
- **controller_controls_mine:** Johnson R L Construction & Coal Co → Overland No 1 Mine; 1950-01-01 to 1974-12-30; source msha-controller-operator-history
- **controller_controls_operator:** Johnson R L Construction & Coal Co → R L Johnson Construction & Coal Company; 1950-01-01 to 1974-12-30; source msha-controller-operator-history
- **operator_operates_mine:** Overland Mining Company → Overland No 1 Mine; 1974-12-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bowie Jack → Overland No 1 Mine; 1974-12-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bowie Jack → Overland Mining Company; 1974-12-31 to current/open; source msha-controller-operator-history