# Relationship history for MSHA mine 4002043

Current hierarchy: **Laco Inc-H & B Mining & Coal Services → Laco Mining Company → No 1 Tipple**

- 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

- **controller_controls_mine:** Laco Inc-H & B Mining & Coal Services → No 1 Tipple; 1973-12-10 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Laco Mining Company → No 1 Tipple; 1976-02-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Laco Inc-H & B Mining & Coal Services → Laco Mining Company; 1976-02-12 to current/open; source msha-controller-operator-history