# Relationship history for MSHA mine 3003694

Current hierarchy: **Patrick O  Armstrong → PAT ARMSTRONG INC → NORTH TI 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:** Patrick O  Armstrong → NORTH TI SAND & GRAVEL; 1997-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Pat Armstrong Inc → NORTH TI SAND & GRAVEL; 2009-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patrick O  Armstrong → Pat Armstrong Inc; 2009-06-29 to current/open; source msha-controller-operator-history