# Relationship history for MSHA mine 2500790

Current hierarchy: **Knight Roger J-Tom Atkins → Knight Asphalt Inc → Knight Asphalt 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

- **operator_operates_mine:** Knight Brothers Inc → Knight Asphalt Pit; 1950-01-01 to 1992-06-01; source msha-controller-operator-history
- **controller_controls_mine:** Knight William R → Knight Asphalt Pit; 1950-01-01 to 1992-06-01; source msha-controller-operator-history
- **controller_controls_operator:** Knight William R → Knight Brothers Inc; 1950-01-01 to 1992-06-01; source msha-controller-operator-history
- **operator_operates_mine:** Knight Asphalt Inc → Knight Asphalt Pit; 1992-06-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Knight Roger J-Tom Atkins Et Al → Knight Asphalt Pit; 1992-06-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Knight Roger J-Tom Atkins Et Al → Knight Asphalt Inc; 1992-06-02 to current/open; source msha-controller-operator-history