# Relationship history for MSHA mine 4609190

Current hierarchy: **Roy E  Collins → Boomerang Coal Inc → Brady 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

- **operator_operates_mine:** Boomerang Coal Inc → Brady Surface; 2006-10-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy E  Collins → Brady Surface; 2006-10-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy E  Collins → Boomerang Coal Inc; 2006-10-18 to current/open; source msha-controller-operator-history