# Relationship history for MSHA mine 2302040

Current hierarchy: **Clark Roy → Big R Sand & Gravel Inc → Big R Sand & Gravel Incorporated**

- 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

- **operator_operates_mine:** Big R Sand & Gravel Inc → Big R Sand & Gravel Incorporated; 1991-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Clark Roy → Big R Sand & Gravel Incorporated; 1991-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Clark Roy → Big R Sand & Gravel Inc; 1991-04-01 to current/open; source msha-controller-operator-history