# Relationship history for MSHA mine 0102220

Current hierarchy: **Brown Boyce & J E → Brown Brothers Coal Company Inc → Jackson Pit**

- 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:** Brown Boyce & J E → Jackson Pit; 1976-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brown Brothers Coal Company Inc → Jackson Pit; 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brown Boyce & J E → Brown Brothers Coal Company Inc; 1980-06-01 to current/open; source msha-controller-operator-history