# Relationship history for MSHA mine 1506825

Current hierarchy: **Hobert  Newman → Toni-Elkhorn Mining Company Inc → No 1 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

- **controller_controls_mine:** Newman Berman & Wendell → No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Newman Coal Company → No 1 Mine; 1973-01-01 to 1978-05-30; source msha-controller-operator-history
- **controller_controls_operator:** Newman Berman & Wendell → Newman Coal Company; 1973-01-01 to 1978-05-30; source msha-controller-operator-history
- **operator_operates_mine:** Toni-Elkhorn Mining Company Inc → No 1 Mine; 1978-05-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hobert  Newman → No 1 Mine; 1978-05-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hobert  Newman → Toni-Elkhorn Mining Company Inc; 1978-05-31 to current/open; source msha-controller-operator-history