# Relationship history for MSHA mine 1517214

Current hierarchy: **Conley C Thomas → Blackheart Inc → Brushy Fork Surface**

- 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

- **controller_controls_mine:** Conley C Thomas → Brushy Fork Surface; 1990-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Blackheart Inc → Brushy Fork Surface; 1992-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Conley C Thomas → Blackheart Inc; 1992-03-01 to current/open; source msha-controller-operator-history
