# Relationship history for MSHA mine 4605434

Current hierarchy: **Westbury Coal Inc & Sewickley Coal Management Inc → J & J Coal Mining Partnership → Pokey #2 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:** J & J Coal Mining Partnership → Pokey #2 Mine; 1977-03-03 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Westbury Coal Inc & Sewickley Coal Management Inc → Pokey #2 Mine; 1977-03-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Westbury Coal Inc & Sewickley Coal Management Inc → J & J Coal Mining Partnership; 1977-03-03 to current/open; source msha-controller-operator-history