# Relationship history for MSHA mine 4405683

Current hierarchy: **Deel Nubern-William → Ivy Branch Coal Company Inc → #15**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Deel Nubern-William Et Al → #15; 1980-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ivy Branch Coal Company Inc → #15; 1981-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Deel Nubern-William Et Al → Ivy Branch Coal Company Inc; 1981-07-01 to current/open; source msha-controller-operator-history