# Relationship history for MSHA mine 2103002

Current hierarchy: **Wacker Ronald F → Wacker Brothers Construction & Son → Cone Crushing**

- 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:** Wacker Brothers Construction & Son → Cone Crushing; 1989-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wacker Ronald F → Cone Crushing; 1989-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wacker Ronald F → Wacker Brothers Construction & Son; 1989-10-01 to current/open; source msha-controller-operator-history