# Relationship history for MSHA mine 3609624

Current hierarchy: **Scott R  Middendorf; Christopher L  Roof → M R Dirt → Forbes 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:** M R Dirt → Forbes Pit; 2008-05-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Christopher L  Roof et al → Forbes Pit; 2008-05-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Christopher L  Roof et al → M R Dirt; 2008-05-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Scott R  Middendorf et al → M R Dirt; 2008-05-12 to current/open; source msha-controller-operator-history