# Relationship history for MSHA mine 3503883

Current hierarchy: **Jason E  Curtis; Sarah B  Curtis → Curtis Excavation, LLC → Curtis Rock**

- 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:** Curtis Excavation, LLC → Curtis Rock; 2019-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jason E  Curtis et al → Curtis Rock; 2019-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jason E  Curtis et al → Curtis Excavation, LLC; 2019-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sarah B  Curtis et al → Curtis Excavation, LLC; 2019-02-11 to current/open; source msha-controller-operator-history