# Relationship history for MSHA mine 4103645

Current hierarchy: **Whitlow Ed → J & W Sand & Gravel Company Inc → J&W SAND&GRAV CO INC**

- 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:** Whitlow Ed → J&W SAND&GRAV CO INC; 1990-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** J & W Sand & Gravel Company Inc → J&W SAND&GRAV CO INC; 1990-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Whitlow Ed → J & W Sand & Gravel Company Inc; 1990-11-01 to current/open; source msha-controller-operator-history