# Relationship history for MSHA mine 4606617

Current hierarchy: **Anderson Arthur L → Triple A Coals Inc → #2 Surface**

- 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:** Anderson Arthur L → #2 Surface; 1976-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Technology Production Inc → #2 Surface; 1982-12-01 to 1984-09-25; source msha-controller-operator-history
- **controller_controls_mine:** Basham Calvin R Et Al → #2 Surface; 1982-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Basham Calvin R Et Al → Technology Production Inc; 1982-12-01 to 1984-09-25; source msha-controller-operator-history
- **operator_operates_mine:** Triple A Coals Inc → #2 Surface; 1984-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Anderson Arthur L → Triple A Coals Inc; 1984-09-26 to current/open; source msha-controller-operator-history