# Relationship history for MSHA mine 4606724

Current hierarchy: **Brewster Thomas → Mar-San Corp → Mountaineer**

- 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:** Mar-San Corp → Mountaineer; 1983-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brewster Thomas → Mountaineer; 1983-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brewster Thomas → Mar-San Corp; 1983-11-01 to current/open; source msha-controller-operator-history