# Relationship history for MSHA mine 4400589

Current hierarchy: **Hobbs Rex → Hobbs Brothers Coal Company → No 15 U G**

- 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:** Hobbs Brothers Coal Company → No 15 U G; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hobbs Rex → No 15 U G; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hobbs Rex → Hobbs Brothers Coal Company; 1950-01-01 to current/open; source msha-controller-operator-history