# Relationship history for MSHA mine 4105172

Current hierarchy: **Pedro  Martinez → Alvarado Sand and Gravel LLC → Alvarado Sand and 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Alvarado Sand and Gravel LLC → Alvarado Sand and Gravel; 2016-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Pedro  Martinez → Alvarado Sand and Gravel; 2016-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pedro  Martinez → Alvarado Sand and Gravel LLC; 2016-02-11 to current/open; source msha-controller-operator-history