# Relationship history for MSHA mine 0503621

Current hierarchy: **Mosch Alvin → Mosch Exploration & Mining Company → Brighton Mine**

- 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:** Mosch Exploration & Mining Company → Brighton Mine; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mosch Alvin → Brighton Mine; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mosch Alvin → Mosch Exploration & Mining Company; 1980-02-01 to current/open; source msha-controller-operator-history