# Relationship history for MSHA mine 3503620

Current hierarchy: **Merle M  Mitchell → Mid Pacific Enterprises Inc → Hills Quarry**

- 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:** Merle M  Mitchell → Hills Quarry; 2005-05-05 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mid Pacific Enterprises Inc → Hills Quarry; 2005-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Merle M  Mitchell → Mid Pacific Enterprises Inc; 2005-07-20 to current/open; source msha-controller-operator-history