# Relationship history for MSHA mine 0801181

Current hierarchy: **Superfos America Inc → Okaloosa Asphalt Inc → Crestview**

- 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:** Okaloosa Asphalt Inc → Crestview; 1991-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Superfos America Inc → Crestview; 1991-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Superfos America Inc → Okaloosa Asphalt Inc; 1991-09-01 to current/open; source msha-controller-operator-history