# Relationship history for MSHA mine 1516571

Current hierarchy: **Ritchie Levi Haskel & Joseph B → Ritchie Brothers Construction → Ritchie Bros Const No 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:** Ritchie Brothers Construction → Ritchie Bros Const No 1; 1989-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ritchie Levi Haskel & Joseph B → Ritchie Bros Const No 1; 1989-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ritchie Levi Haskel & Joseph B → Ritchie Brothers Construction; 1989-02-01 to current/open; source msha-controller-operator-history