# Relationship history for MSHA mine 0404723

Current hierarchy: **Perry  Thompson → Hat Creek Construction Inc → Ward Lake Pit**

- 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:** Darrel  Miller et al → Ward Lake Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Miller's Custom Work Inc → Ward Lake Pit; 1984-09-01 to 2011-05-22; source msha-controller-operator-history
- **controller_controls_operator:** Darrel  Miller et al → Miller's Custom Work Inc; 1984-09-01 to 2011-05-22; source msha-controller-operator-history
- **controller_controls_mine:** Perry  Thompson  et al → Ward Lake Pit; 1992-02-01 to 2017-02-12; source msha-controller-operator-history
- **operator_operates_mine:** Hat Creek Construction Inc → Ward Lake Pit; 2011-05-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Perry  Thompson  et al → Hat Creek Construction Inc; 2011-05-23 to 2017-02-12; source msha-controller-operator-history
- **controller_controls_operator:** Bob  Thompson  et al → Hat Creek Construction Inc; 2011-05-23 to 2017-02-12; source msha-controller-operator-history
- **controller_controls_mine:** Perry  Thompson → Ward Lake Pit; 2017-02-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Perry  Thompson → Hat Creek Construction Inc; 2017-02-13 to current/open; source msha-controller-operator-history