# Relationship history for MSHA mine 1800008

Current hierarchy: **Aggregate Management, Inc → S W Barrick & Sons → S W Barrick & Sons**

- 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:** S W Barrick & Sons Inc → S W Barrick & Sons; 1950-01-01 to 1990-06-09; source msha-controller-operator-history
- **controller_controls_mine:** Samuel W  Barrick → S W Barrick & Sons; 1950-01-01 to 1990-06-09; source msha-controller-operator-history
- **controller_controls_operator:** Samuel W  Barrick → S W Barrick & Sons Inc; 1950-01-01 to 1990-06-09; source msha-controller-operator-history
- **operator_operates_mine:** S W Barrick & Sons → S W Barrick & Sons; 1990-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Aggregate Management, Inc → S W Barrick & Sons; 1990-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Aggregate Management, Inc → S W Barrick & Sons; 1990-06-10 to current/open; source msha-controller-operator-history