# Relationship history for MSHA mine 1201951

Current hierarchy: **Clarkson William F Iii → Clarkson Company Mine #1 Inc → The Clarkson Company Mine #1 Inc**

- 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:** Clarkson Company Mine #1 Inc → The Clarkson Company Mine #1 Inc; 1984-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Clarkson William F Iii → The Clarkson Company Mine #1 Inc; 1984-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Clarkson William F Iii → Clarkson Company Mine #1 Inc; 1984-08-01 to current/open; source msha-controller-operator-history