# Relationship history for MSHA mine 0600654

Current hierarchy: **CRH PLC → Tilcon Connecticut Inc → Griswold 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

- **operator_operates_mine:** Soneco/Northeastern Inc → Griswold Sand & Gravel; 1996-09-01 to 2000-02-21; source msha-controller-operator-history
- **controller_controls_mine:** Christopher  Mc Laughlin → Griswold Sand & Gravel; 1996-09-01 to 2000-02-21; source msha-controller-operator-history
- **controller_controls_operator:** Christopher  Mc Laughlin → Soneco/Northeastern Inc; 1996-09-01 to 2000-02-21; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Griswold Sand & Gravel; 1996-09-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Tilcon Connecticut Inc → Griswold Sand & Gravel; 2000-02-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Tilcon Connecticut Inc; 2000-02-22 to current/open; source msha-controller-operator-history