# Relationship history for MSHA mine 4201746

Current hierarchy: **U C O Inc → Winter Quarters Mining Corp → Scofield 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:** Winter Quarters Mining Corp → Scofield Mine; 1981-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** U C O Inc → Scofield Mine; 1981-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** U C O Inc → Winter Quarters Mining Corp; 1981-07-01 to current/open; source msha-controller-operator-history