# Relationship history for MSHA mine 3503547

Current hierarchy: **Delbert L  Barber Sr → Del Barber Excavation, Inc. → Barber #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:** Del Barber Excavation, Inc. → Barber #1; 2001-10-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Delbert L  Barber Sr → Barber #1; 2001-10-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Delbert L  Barber Sr → Del Barber Excavation, Inc.; 2001-10-24 to current/open; source msha-controller-operator-history