# Relationship history for MSHA mine 1300924

Current hierarchy: **Carlson Donald & Ernest → Carlson Brothers → Carlson Brothers 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Carlson Brothers → Carlson Brothers Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Carlson Donald & Ernest → Carlson Brothers Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Carlson Donald & Ernest → Carlson Brothers; 1950-01-01 to current/open; source msha-controller-operator-history