# Relationship history for MSHA mine 1516692

Current hierarchy: **Daugherty Roger A → Buccaneer Coal Company Inc → Lower Buc**

- 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:** Buccaneer Coal Company Inc → Lower Buc; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Daugherty Roger A → Lower Buc; 1989-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daugherty Roger A → Buccaneer Coal Company Inc; 1989-08-01 to current/open; source msha-controller-operator-history