# Relationship history for MSHA mine 1519038

Current hierarchy: **Robert C  Billips → Bayonet MNG. Co, Inc → Wright Fork**

- 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

- **controller_controls_mine:** Robert C  Billips → Wright Fork; 1995-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bayonet MNG. Co, Inc → Wright Fork; 2006-08-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert C  Billips → Bayonet MNG. Co, Inc; 2006-08-31 to current/open; source msha-controller-operator-history