# Relationship history for MSHA mine 3002968

Current hierarchy: **Greene Donald C → D C G Development Company → Ushers Industrial Park**

- 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 C G Development Company → Ushers Industrial Park; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Greene Donald C → Ushers Industrial Park; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greene Donald C → D C G Development Company; 1990-07-01 to current/open; source msha-controller-operator-history