# Relationship history for MSHA mine 3901343

Current hierarchy: **Doerr Leonard C & R E Robinson → Rambo Mining Company → Atlantic**

- 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:** Rambo Mining Company → Atlantic; 1985-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Doerr Leonard C & R E Robinson → Atlantic; 1985-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Doerr Leonard C & R E Robinson → Rambo Mining Company; 1985-11-01 to current/open; source msha-controller-operator-history