# Relationship history for MSHA mine 3901538

Current hierarchy: **Steve L.  Priebe; Wes R.  Priebe → Lloyd Priebe & Sons Construction Inc → Portable #1**

- 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:** Lloyd Priebe & Sons Construction Inc → Portable #1; 2009-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Steve L.  Priebe et al → Portable #1; 2009-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steve L.  Priebe et al → Lloyd Priebe & Sons Construction Inc; 2009-04-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wes R.  Priebe et al → Lloyd Priebe & Sons Construction Inc; 2009-04-30 to current/open; source msha-controller-operator-history