# Relationship history for MSHA mine 4202183

Current hierarchy: **Merrick  Young → Merrick Young Inc → Young Mobile Unit 1**

- 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:** Merrick Young Inc → Young Mobile Unit 1; 1997-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Merrick  Young → Young Mobile Unit 1; 1997-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Merrick  Young → Merrick Young Inc; 1997-08-01 to current/open; source msha-controller-operator-history