# Relationship history for MSHA mine 4104029

Current hierarchy: **Curtis Glenn Thurman → Thurman Transportation Inc → Thurman Transportation Inc Hwy 67 Sand P**

- 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:** Curtis Glenn Thurman et al → Thurman Transportation Inc Hwy 67 Sand P; 1990-02-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Thurman Transportation Inc → Thurman Transportation Inc Hwy 67 Sand P; 1998-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Curtis Glenn Thurman et al → Thurman Transportation Inc; 1998-09-01 to current/open; source msha-controller-operator-history