# Relationship history for MSHA mine 3609615

Current hierarchy: **Mario B  Vasquez → Mario B Vasquez Stone → Gregerson 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Mario B  Vasquez → Gregerson Quarry; 2008-04-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mario B Vasquez Stone → Gregerson Quarry; 2008-04-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mario B  Vasquez → Mario B Vasquez Stone; 2008-04-16 to current/open; source msha-controller-operator-history