# Relationship history for MSHA mine 4503774

Current hierarchy: **Todd  Johnson → Premier Excavation, Inc → Premier 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:** Premier Excavation, Inc → Premier Crushing; 2017-10-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Todd  Johnson et al → Premier Crushing; 2017-10-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Todd  Johnson et al → Premier Excavation, Inc; 2017-10-18 to current/open; source msha-controller-operator-history