# Relationship history for MSHA mine 3609635

Current hierarchy: **Craig  Keller → Keller Crushing & Screening Inc → Keller Crushing & Screening Inc**

- 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:** Keller Crushing & Screening Inc → Keller Crushing & Screening Inc; 2008-06-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joseph  Keller → Keller Crushing & Screening Inc; 2008-06-23 to 2013-01-08; source msha-controller-operator-history
- **controller_controls_operator:** Joseph  Keller → Keller Crushing & Screening Inc; 2008-06-23 to 2013-01-08; source msha-controller-operator-history
- **controller_controls_mine:** Craig  Keller → Keller Crushing & Screening Inc; 2013-01-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Craig  Keller → Keller Crushing & Screening Inc; 2013-01-09 to current/open; source msha-controller-operator-history