# Relationship history for MSHA mine 1507252

Current hierarchy: **Curlin Peter B → Morc Industries Inc → Rich Strip 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Morc Industries Inc → Rich Strip Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Curlin Peter B → Rich Strip Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Curlin Peter B → Morc Industries Inc; 1950-01-01 to current/open; source msha-controller-operator-history