# Relationship history for MSHA mine 2700420

Current hierarchy: **Keith B  Foote → Big Foote Crushing LLC → Portable Unit #2**

- 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:** Ernest J  Thibeault III → Portable Unit #2; 1997-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Keith B  Foote → Portable Unit #2; 2004-04-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Thibeault Corp → Portable Unit #2; 2007-04-20 to 2026-03-24; source msha-controller-operator-history
- **controller_controls_operator:** Ernest J  Thibeault III → Thibeault Corp; 2007-04-20 to 2026-03-24; source msha-controller-operator-history
- **operator_operates_mine:** Big Foote Crushing LLC → Portable Unit #2; 2026-03-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keith B  Foote → Big Foote Crushing LLC; 2026-03-25 to current/open; source msha-controller-operator-history