# Relationship history for MSHA mine 1507132

Current hierarchy: **Massey Energy Company → Stone Mining Company → No A-5 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

- **controller_controls_mine:** Pittston Company → No A-5 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Eastern Coal Corp → No A-5 Mine; 1974-01-01 to 1993-02-22; source msha-controller-operator-history
- **controller_controls_operator:** Pittston Company → Eastern Coal Corp; 1974-01-01 to 1993-02-22; source msha-controller-operator-history
- **operator_operates_mine:** Stone Mining Company → No A-5 Mine; 1993-02-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → No A-5 Mine; 1993-02-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Stone Mining Company; 1993-02-23 to current/open; source msha-controller-operator-history