# Relationship history for MSHA mine 4703313

Current hierarchy: **Larry  Burcalow → Yahara Materials Inc → Unit No. 13**

- 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:** Larry  Burcalow → Unit No. 13; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Yahara Materials Inc → Unit No. 13; 2002-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry  Burcalow → Yahara Materials Inc; 2002-07-08 to current/open; source msha-controller-operator-history