# Relationship history for MSHA mine 3401751

Current hierarchy: **Harris Robert E → Bob Harris Dirt Contracting → Harris 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:** Bob Harris Dirt Contracting → Harris Pit; 1991-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Harris Robert E → Harris Pit; 1991-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harris Robert E → Bob Harris Dirt Contracting; 1991-04-01 to current/open; source msha-controller-operator-history