# Relationship history for MSHA mine 5400351

Current hierarchy: **Efrain D  Vassallo → Marmoles Vassco Inc → Marmoles Vassco Inc Quarry**

- 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:** Efrain D  Vassallo → Marmoles Vassco Inc Quarry; 1988-07-28 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Marmoles Vassco Inc → Marmoles Vassco Inc Quarry; 1993-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Efrain D  Vassallo → Marmoles Vassco Inc; 1993-05-01 to current/open; source msha-controller-operator-history