# Relationship history for MSHA mine 4202106

Current hierarchy: **Gann Patricia → P G Trucking Inc → Elk Hill Portable Rock Products**

- 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:** P G Trucking Inc → Elk Hill Portable Rock Products; 1994-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gann Patricia → Elk Hill Portable Rock Products; 1994-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gann Patricia → P G Trucking Inc; 1994-06-01 to current/open; source msha-controller-operator-history