# Relationship history for MSHA mine 4001934

Current hierarchy: **Cook Earl → D & E Coal Company Inc → No 1 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

- **operator_operates_mine:** D & E Coal Company Inc → No 1 Mine; 1975-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cook Earl → No 1 Mine; 1975-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cook Earl → D & E Coal Company Inc; 1975-10-01 to current/open; source msha-controller-operator-history