# Relationship history for MSHA mine 4202352

Current hierarchy: **Grant  Wadman → Western Builders, Inc. → Portable**

- 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:** Western Builders, Inc. → Portable; 2002-06-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Grant  Wadman → Portable; 2002-06-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Grant  Wadman → Western Builders, Inc.; 2002-06-25 to current/open; source msha-controller-operator-history