# Relationship history for MSHA mine 3602693

Current hierarchy: **Crown Coal & Coke Company → Pembroke Coal Company → Pembroke #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:** Decker Construction Company → Pembroke #1 Mine; 1950-01-01 to 1977-09-18; source msha-controller-operator-history
- **controller_controls_mine:** Decker Robert W → Pembroke #1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Decker Robert W → Decker Construction Company; 1950-01-01 to 1977-09-18; source msha-controller-operator-history
- **operator_operates_mine:** Pembroke Coal Company → Pembroke #1 Mine; 1977-09-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Crown Coal & Coke Company → Pembroke #1 Mine; 1977-09-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Crown Coal & Coke Company → Pembroke Coal Company; 1977-09-19 to current/open; source msha-controller-operator-history