# Relationship history for MSHA mine 2602155

Current hierarchy: **White Park Research & Development Ltd → White Park Research & Development Ltd → White Park Mill**

- 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:** White Park Research & Development Ltd → White Park Mill; 1990-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** White Park Research & Development Ltd → White Park Mill; 1990-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** White Park Research & Development Ltd → White Park Research & Development Ltd; 1990-05-01 to current/open; source msha-controller-operator-history