# Relationship history for MSHA mine 0405995

Current hierarchy: **Allen S  Zanker; Ronald Evan  Zanker → Zanker and Zanker → Dawson 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:** Zanker and Zanker → Dawson Quarry; 2026-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Allen S  Zanker et al → Dawson Quarry; 2026-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Allen S  Zanker et al → Zanker and Zanker; 2026-09-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronald Evan  Zanker et al → Zanker and Zanker; 2026-09-21 to current/open; source msha-controller-operator-history