# Relationship history for MSHA mine 0201886

Current hierarchy: **Skousen W R → W R Skousen Contractor Inc → Portable Crusher 512-10126**

- 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:** Skousen W R → Portable Crusher 512-10126; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** W R Skousen Contractor Inc → Portable Crusher 512-10126; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Skousen W R → W R Skousen Contractor Inc; 1978-03-09 to current/open; source msha-controller-operator-history