# Relationship history for MSHA mine 4501977

Current hierarchy: **ITT Corp → Itt Rayonier Inc → Duncan 5000 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

- **controller_controls_mine:** ITT Corp → Duncan 5000 Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Spoelstra Brothers Inc → Duncan 5000 Pit; 1950-01-01 to 1979-06-11; source msha-controller-operator-history
- **controller_controls_mine:** Spoelstra Ted → Duncan 5000 Pit; 1950-01-01 to 1979-06-11; source msha-controller-operator-history
- **controller_controls_operator:** Spoelstra Ted → Spoelstra Brothers Inc; 1950-01-01 to 1979-06-11; source msha-controller-operator-history
- **operator_operates_mine:** Itt Rayonier Inc → Duncan 5000 Pit; 1979-06-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** ITT Corp → Itt Rayonier Inc; 1979-06-12 to current/open; source msha-controller-operator-history