# Relationship history for MSHA mine 1601144

Current hierarchy: **Knight Steve → Steve Knight Sand & Gravel Company → Mitchell 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:** Knight Steve → Mitchell Pit; 1985-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Steve Knight Sand & Gravel Company → Mitchell Pit; 1987-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Knight Steve → Steve Knight Sand & Gravel Company; 1987-10-01 to current/open; source msha-controller-operator-history