# Relationship history for MSHA mine 3901250

Current hierarchy: **Fran  Schoonover → Schoonover Brothers → Schoonover Crusher**

- 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

- **controller_controls_mine:** Fran  Schoonover et al → Schoonover Crusher; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Schoonover Brothers → Schoonover Crusher; 1980-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fran  Schoonover et al → Schoonover Brothers; 1980-09-01 to current/open; source msha-controller-operator-history