# Relationship history for MSHA mine 4607825

Current hierarchy: **Bell Douglas-Casset Bias → Laurel Coal Corp → Buffalo 10**

- 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:** Bell Douglas-Casset Bias Et Al → Buffalo 10; 1987-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Laurel Coal Corp → Buffalo 10; 1990-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bell Douglas-Casset Bias Et Al → Laurel Coal Corp; 1990-01-01 to current/open; source msha-controller-operator-history