# Relationship history for MSHA mine 3607380

Current hierarchy: **Henckel Lawrence & Charles E Brooks → H & B Coal Company → H & B Coal Co**

- 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:** H & B Coal Company → H & B Coal Co; 1982-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Henckel Lawrence & Charles E Brooks → H & B Coal Co; 1982-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Henckel Lawrence & Charles E Brooks → H & B Coal Company; 1982-09-01 to current/open; source msha-controller-operator-history