# Relationship history for MSHA mine 2003503

Current hierarchy: **Thomas D  Smiljanich → Smily's Excavating & Trucking → Screen Plant**

- 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:** Smily's Excavating & Trucking → Screen Plant; 2014-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thomas D  Smiljanich → Screen Plant; 2014-10-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas D  Smiljanich → Smily's Excavating & Trucking; 2014-10-21 to current/open; source msha-controller-operator-history