# Relationship history for MSHA mine 4703621

Current hierarchy: **Timothy L  Zillges → Zillges Materials, Inc. → Masaba Wash Plant**

- 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:** Timothy L  Zillges → Masaba Wash Plant; 2006-08-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Zillges Materials Inc → Masaba Wash Plant; 2011-09-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Timothy L  Zillges → Zillges Materials Inc; 2011-09-08 to current/open; source msha-controller-operator-history