# Relationship history for MSHA mine 4403737

Current hierarchy: **Mullins Denver L & Wayne--Mike Brooks → Nova Coal Co → 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

- **controller_controls_mine:** Mullins Denver L & Wayne--Mike Brooks → No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dadem Coal Corp → No 1 Mine; 1974-01-01 to 1975-07-24; source msha-controller-operator-history
- **controller_controls_mine:** Ball D C → No 1 Mine; 1974-01-01 to 1975-07-24; source msha-controller-operator-history
- **controller_controls_operator:** Ball D C → Dadem Coal Corp; 1974-01-01 to 1975-07-24; source msha-controller-operator-history
- **operator_operates_mine:** Nova Coal Co → No 1 Mine; 1975-07-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mullins Denver L & Wayne--Mike Brooks → Nova Coal Co; 1975-07-25 to current/open; source msha-controller-operator-history