# Relationship history for MSHA mine 1514543

Current hierarchy: **Saiah D & F Engleman → B X Corp → No 1 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Saiah D & F Engleman → No 1 Surface; 1984-03-12 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** B X Corp → No 1 Surface; 1984-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Saiah D & F Engleman → B X Corp; 1984-04-01 to current/open; source msha-controller-operator-history