# Relationship history for MSHA mine 1001775

Current hierarchy: **Vienna International Ltd → Vienna International Ltd → Vienna International**

- 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

- **operator_operates_mine:** Vienna International Ltd → Vienna International; 1987-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Vienna International Ltd → Vienna International; 1987-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vienna International Ltd → Vienna International Ltd; 1987-04-01 to current/open; source msha-controller-operator-history