# Relationship history for MSHA mine 3607520

Current hierarchy: **Kletzli Nelson B → N B Kletzli Jr Coal & Development Company → East Run**

- 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:** N B Kletzli Jr Coal & Development Company → East Run; 1984-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kletzli Nelson B → East Run; 1984-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kletzli Nelson B → N B Kletzli Jr Coal & Development Company; 1984-02-01 to current/open; source msha-controller-operator-history