# Relationship history for MSHA mine 4404766

Current hierarchy: **Hylton Walter & Mary → Little B Coal Company → No 6 Strip**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Hylton Walter & Mary → No 6 Strip; 1973-12-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Little B Coal Company → No 6 Strip; 1977-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hylton Walter & Mary → Little B Coal Company; 1977-06-01 to current/open; source msha-controller-operator-history