# Relationship history for MSHA mine 1103276

Current hierarchy: **Billie  Roberts → BRAK LLC → Calvin Sand and Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** BRAK LLC → Calvin Sand and Gravel; 2015-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Billie  Roberts → Calvin Sand and Gravel; 2015-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Billie  Roberts → BRAK LLC; 2015-09-23 to current/open; source msha-controller-operator-history