# Relationship history for MSHA mine 4104359

Current hierarchy: **Michael D  Smith → LS  SAND & GRAVEL LTD. → SMITH RANCH MINE**

- 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:** LS  SAND & GRAVEL LTD. → SMITH RANCH MINE; 2002-04-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael D  Smith → SMITH RANCH MINE; 2002-04-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael D  Smith → LS  SAND & GRAVEL LTD.; 2002-04-11 to current/open; source msha-controller-operator-history