# Relationship history for MSHA mine 4609232

Current hierarchy: **Massey Energy Company → Massey Energy Co. → Superior Highwall Miner # 54**

- 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:** Massey Energy Co. → Superior Highwall Miner # 54; 2007-10-03 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → Superior Highwall Miner # 54; 2007-10-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Massey Energy Co.; 2007-10-03 to current/open; source msha-controller-operator-history