# Relationship history for MSHA mine 3610171

Current hierarchy: **John M  Stilley → Amerikohl Aggregates Inc → Gardner 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** John M  Stilley → Gardner Quarry; 2011-07-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Amerikohl Aggregates Inc → Gardner Quarry; 2016-03-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John M  Stilley → Amerikohl Aggregates Inc; 2016-03-18 to current/open; source msha-controller-operator-history