# Relationship history for MSHA mine 4605006

Current hierarchy: **Warmac Mining Company Inc → D & D Coal Company → No 2 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:** Warmac Mining Company Inc Et Al → No 2 Mine; 1975-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** D & D Coal Company → No 2 Mine; 1975-12-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warmac Mining Company Inc Et Al → D & D Coal Company; 1975-12-15 to current/open; source msha-controller-operator-history