# Relationship history for MSHA mine 3605617

Current hierarchy: **Burton Leroy → Cardinal Coal & Contracting Company → Owens Strip**

- 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:** Cardinal Coal & Contracting Company → Owens Strip; 1975-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Burton Leroy → Owens Strip; 1975-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Burton Leroy → Cardinal Coal & Contracting Company; 1975-06-01 to current/open; source msha-controller-operator-history