# Relationship history for MSHA mine 1601175

Current hierarchy: **Roy  Hunt → Hunt Sand & Gravel → HUNT SAND & GRAVEL**

- 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:** Roy  Hunt → HUNT SAND & GRAVEL; 1986-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hunt Sand & Gravel → HUNT SAND & GRAVEL; 1988-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy  Hunt → Hunt Sand & Gravel; 1988-08-01 to current/open; source msha-controller-operator-history