# Relationship history for MSHA mine 0503927

Current hierarchy: **Monks Robert E → R E Monks Construction Company → Airport Pit #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

- **controller_controls_mine:** Kerrigan D R → Airport Pit #2; 1982-09-14 to 1984-05-31; source msha-controller-operator-history
- **operator_operates_mine:** Kerrigan Brothers → Airport Pit #2; 1984-01-01 to 1984-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Kerrigan D R → Kerrigan Brothers; 1984-01-01 to 1984-05-31; source msha-controller-operator-history
- **operator_operates_mine:** R E Monks Construction Company → Airport Pit #2; 1984-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Monks Robert E → Airport Pit #2; 1984-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Monks Robert E → R E Monks Construction Company; 1984-06-01 to current/open; source msha-controller-operator-history