# Relationship history for MSHA mine 2402168

Current hierarchy: **Lyle  Stenberg; Ray  Stenberg → Stenberg Construction & Supply Inc → PORTABLE SCREENING PLANT**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Stenberg Construction & Supply Inc → PORTABLE SCREENING PLANT; 1999-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lyle  Stenberg et al → PORTABLE SCREENING PLANT; 1999-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lyle  Stenberg et al → Stenberg Construction & Supply Inc; 1999-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ray  Stenberg et al → Stenberg Construction & Supply Inc; 1999-03-01 to current/open; source msha-controller-operator-history