# Relationship history for MSHA mine 1513580

Current hierarchy: **Simpson Ronald K-Pat → P B & S Coal Company → No 1**

- 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:** P B & S Coal Company → No 1; 1982-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Simpson Ronald K-Pat Et Al → No 1; 1982-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Simpson Ronald K-Pat Et Al → P B & S Coal Company; 1982-07-01 to current/open; source msha-controller-operator-history