# Relationship history for MSHA mine 4703518

Current hierarchy: **David C  Behrens; Patti L  Behrens → David Behrens Construction Inc → Three B's 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

- **operator_operates_mine:** David Behrens Construction Inc → Three B's Quarry; 2007-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David C  Behrens  et al → Three B's Quarry; 2007-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David C  Behrens  et al → David Behrens Construction Inc; 2007-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patti L  Behrens  et al → David Behrens Construction Inc; 2007-10-31 to current/open; source msha-controller-operator-history