# Relationship history for MSHA mine 3901376

Current hierarchy: **Rosane Douglas & Dennis → R A & S Contracting Company → Portable Screen #4**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Rosane Douglas & Dennis → Portable Screen #4; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** R A & S Contracting Company → Portable Screen #4; 1990-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rosane Douglas & Dennis → R A & S Contracting Company; 1990-05-01 to current/open; source msha-controller-operator-history