# Relationship history for MSHA mine 2000902

Current hierarchy: **Oerther Brothers Excavating → Oerther Brothers Excavating → Rock Crete Products Pit**

- 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:** Rock Crete Products → Rock Crete Products Pit; 1950-01-01 to 1980-09-24; source msha-controller-operator-history
- **controller_controls_mine:** Marcello  Scapitticci et al → Rock Crete Products Pit; 1950-01-01 to 1980-09-24; source msha-controller-operator-history
- **controller_controls_operator:** Marcello  Scapitticci et al → Rock Crete Products; 1950-01-01 to 1980-09-24; source msha-controller-operator-history
- **operator_operates_mine:** Oerther Brothers Excavating → Rock Crete Products Pit; 1980-09-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Oerther Brothers Excavating → Rock Crete Products Pit; 1980-09-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Oerther Brothers Excavating → Oerther Brothers Excavating; 1980-09-25 to current/open; source msha-controller-operator-history