# Relationship history for MSHA mine 1507970

Current hierarchy: **Cornett Hiram → Cornett Coal Company → 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Cornett Coal Company → No 1 Mine; 1975-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cornett Hiram → No 1 Mine; 1975-01-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cornett Hiram → Cornett Coal Company; 1975-01-08 to current/open; source msha-controller-operator-history