# Relationship history for MSHA mine 4102205

Current hierarchy: **Jesse Lee  Thompson → A & T Sand and Gravel → A & T Sand and Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** A & T Sand and Gravel → A & T Sand and Gravel; 1950-01-01 to 2010-10-20; source msha-controller-operator-history
- **controller_controls_mine:** Alan  Ethridge → A & T Sand and Gravel; 1950-01-01 to 2007-02-20; source msha-controller-operator-history
- **controller_controls_operator:** Alan  Ethridge → A & T Sand and Gravel; 1950-01-01 to 2007-02-20; source msha-controller-operator-history
- **controller_controls_mine:** Howard  Shipman → A & T Sand and Gravel; 2007-02-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Howard  Shipman → A & T Sand and Gravel; 2007-02-21 to 2010-10-20; source msha-controller-operator-history
- **operator_operates_mine:** A & T Sand and Gravel → A & T Sand and Gravel; 2010-10-21 to 2012-01-09; source msha-controller-operator-history
- **controller_controls_mine:** Tonya  Shipman → A & T Sand and Gravel; 2010-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tonya  Shipman → A & T Sand and Gravel; 2010-10-21 to 2012-01-09; source msha-controller-operator-history
- **operator_operates_mine:** A & T Sand and Gravel → A & T Sand and Gravel; 2012-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jesse Lee  Thompson → A & T Sand and Gravel; 2012-01-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jesse Lee  Thompson → A & T Sand and Gravel; 2012-01-10 to current/open; source msha-controller-operator-history