# Relationship history for MSHA mine 0202468

Current hierarchy: **Byers Richard L → Havasu Materials → Havasu Materials**

- 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:** Havasu Materials → Havasu Materials; 1988-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Byers Richard L → Havasu Materials; 1988-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Byers Richard L → Havasu Materials; 1988-11-01 to current/open; source msha-controller-operator-history