# Relationship history for MSHA mine 1701096

Current hierarchy: **Mike J  Thornton → Thornton Construction, Inc. → Chieftain Screen**

- 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

- **controller_controls_mine:** Mike J  Thornton → Chieftain Screen; 2004-02-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Thornton Construction, Inc. → Chieftain Screen; 2023-06-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mike J  Thornton → Thornton Construction, Inc.; 2023-06-14 to current/open; source msha-controller-operator-history