# Relationship history for MSHA mine 4700586

Current hierarchy: **Inland Steel Industries Inc → Jackson County Iron Company → Black River Falls Mine And Mill**

- 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:** Jackson County Iron Company → Black River Falls Mine And Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Inland Steel Industries Inc → Black River Falls Mine And Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Inland Steel Industries Inc → Jackson County Iron Company; 1950-01-01 to current/open; source msha-controller-operator-history