# Relationship history for MSHA mine 4801778

Current hierarchy: **John O  Lee → Ace Engineering, Inc. → Arrow-Shield**

- 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:** Ace Engineering, Inc. → Arrow-Shield; 2014-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John O  Lee → Arrow-Shield; 2014-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John O  Lee → Ace Engineering, Inc.; 2014-03-27 to current/open; source msha-controller-operator-history