# Relationship history for MSHA mine 3608386

Current hierarchy: **Barbuschak Richard → Barbuschak Excavating → Job #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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Barbuschak Excavating → Job #1; 1993-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Barbuschak Richard → Job #1; 1993-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Barbuschak Richard → Barbuschak Excavating; 1993-02-01 to current/open; source msha-controller-operator-history