# Relationship history for MSHA mine 0405420

Current hierarchy: **Paul D  Ford → Robert R Ford Trucking Inc → Pacific Clay**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Robert R Ford Trucking Inc → Pacific Clay; 2000-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Paul D  Ford → Pacific Clay; 2000-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Paul D  Ford → Robert R Ford Trucking Inc; 2000-03-01 to current/open; source msha-controller-operator-history