# Relationship history for MSHA mine 2601921

Current hierarchy: **Bilyeu Kerry → Custom Crushing 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Custom Crushing Inc → Portable #1; 1985-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bilyeu Kerry → Portable #1; 1985-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bilyeu Kerry → Custom Crushing Inc; 1985-04-01 to current/open; source msha-controller-operator-history