# Relationship history for MSHA mine 1518551

Current hierarchy: **Dave  Kingen → Keystone Senior, LLC → Keystone**

- 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:** Keystone Senior, LLC → Keystone; 2002-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dave  Kingen → Keystone; 2002-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dave  Kingen → Keystone Senior, LLC; 2002-06-13 to current/open; source msha-controller-operator-history