# Relationship history for MSHA mine 2602579

Current hierarchy: **Stephen  Harker; Joseph  Harker → Harker & Sons LLC → Harker Portable**

- 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:** Harker & Sons LLC → Harker Portable; 2005-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joseph  Harker et al → Harker Portable; 2005-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joseph  Harker et al → Harker & Sons LLC; 2005-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stephen  Harker et al → Harker & Sons LLC; 2005-11-30 to current/open; source msha-controller-operator-history