# Relationship history for MSHA mine 4403717

Current hierarchy: **Dotson Rail & Dexter → R & D Coal Company → Splashdam No 25 Mine**

- 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:** Dotson Rail & Dexter → Splashdam No 25 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** R & D Coal Company → Splashdam No 25 Mine; 1974-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dotson Rail & Dexter → R & D Coal Company; 1974-01-01 to current/open; source msha-controller-operator-history
