# Relationship history for MSHA mine 3003866

Current hierarchy: **Douglas C  Kohorst → Attica Sand & Gravel → Attica Sand & Gravel Inc**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Attica Sand & Gravel → Attica Sand & Gravel Inc; 2012-11-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Douglas C  Kohorst → Attica Sand & Gravel Inc; 2012-11-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Douglas C  Kohorst → Attica Sand & Gravel; 2012-11-14 to current/open; source msha-controller-operator-history