# Relationship history for MSHA mine 3003228

Current hierarchy: **Thomas Ken → Ken Thomas → TNT QUARRY**

- 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:** Ken Thomas → TNT QUARRY; 1998-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thomas Ken → TNT QUARRY; 1998-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas Ken → Ken Thomas; 1998-07-01 to current/open; source msha-controller-operator-history