# Relationship history for MSHA mine 1516246

Current hierarchy: **Spotte I C → Sun Glo Coal Company Inc → No 23**

- 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 23; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Beth Energy Mines Inc → No 23; 1987-11-01 to 1988-11-29; source msha-controller-operator-history
- **controller_controls_operator:** Bethlehem Steel Corp → Beth Energy Mines Inc; 1987-11-01 to 1988-11-29; source msha-controller-operator-history
- **controller_controls_mine:** Spotte I C → No 23; 1988-11-28 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sun Glo Coal Company Inc → No 23; 1988-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Spotte I C → Sun Glo Coal Company Inc; 1988-11-30 to current/open; source msha-controller-operator-history