# Relationship history for MSHA mine 1513494

Current hierarchy: **Zielinski Brothers → Zielinski Construction Corp → Cedar Ridge**

- 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:** Zielinski Brothers → Cedar Ridge; 1976-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Zielinski Construction Corp → Cedar Ridge; 1982-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Zielinski Brothers → Zielinski Construction Corp; 1982-04-01 to current/open; source msha-controller-operator-history