# Relationship history for MSHA mine 1509812

Current hierarchy: **Perry John → Wyandot Corp → Wyandot Surface**

- 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:** Wyandot Corp → Wyandot Surface; 1976-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Perry John → Wyandot Surface; 1976-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Perry John → Wyandot Corp; 1976-07-02 to current/open; source msha-controller-operator-history