# Relationship history for MSHA mine 0203117

Current hierarchy: **Meadow Valley Corp → Ready Mix Inc → Detrital Sand and Gravel Pit**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Meadow Valley Corp → Detrital Sand and Gravel Pit; 1996-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ready Mix Inc → Detrital Sand and Gravel Pit; 2005-11-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Meadow Valley Corp → Ready Mix Inc; 2005-11-15 to current/open; source msha-controller-operator-history