# Relationship history for MSHA mine 0102278

Current hierarchy: **Calvert John D → Compliance Coal Processors Inc → Compliance 8-2**

- 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:** Calvert John D → Compliance 8-2; 1980-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Compliance Coal Processors Inc → Compliance 8-2; 1980-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Calvert John D → Compliance Coal Processors Inc; 1980-12-01 to current/open; source msha-controller-operator-history