# Relationship history for MSHA mine 4801588

Current hierarchy: **Leroy  Morris → LM Excavation → PORTABLE SCREEN #1**

- 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:** Lm Excavation → PORTABLE SCREEN #1; 2001-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Leroy  Morris → PORTABLE SCREEN #1; 2001-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Leroy  Morris → Lm Excavation; 2001-01-01 to current/open; source msha-controller-operator-history