# Relationship history for MSHA mine 3700184

Current hierarchy: **Frank  Mello → Viking Stone Corp → Tiverton Plant**

- 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:** Frank  Mello → Tiverton Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Viking Stone Corp → Tiverton Plant; 1993-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Frank  Mello → Viking Stone Corp; 1993-10-01 to current/open; source msha-controller-operator-history