# Relationship history for MSHA mine 4604071

Current hierarchy: **K C Holding Company → Kessler Coals Inc → No 3a 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:** Bethlehem Steel Corp → No 3a Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bethlehem Mines Corp → No 3a Mine; 1974-05-01 to 1985-01-06; source msha-controller-operator-history
- **controller_controls_operator:** Bethlehem Steel Corp → Bethlehem Mines Corp; 1974-05-01 to 1985-01-06; source msha-controller-operator-history
- **controller_controls_mine:** K C Holding Company → No 3a Mine; 1982-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kessler Coals Inc → No 3a Mine; 1985-01-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** K C Holding Company → Kessler Coals Inc; 1985-01-07 to current/open; source msha-controller-operator-history