# Relationship history for MSHA mine 4500321

Current hierarchy: **Jane A  Hallock → Pioneer Towing Company Inc → Pioneer 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

- **operator_operates_mine:** Pioneer Towing Company Inc → Pioneer Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jane A  Hallock → Pioneer Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jane A  Hallock → Pioneer Towing Company Inc; 1950-01-01 to current/open; source msha-controller-operator-history