# Relationship history for MSHA mine 5100204

Current hierarchy: **Fong Daniel P S → Fong Construction Company Ltd → Fong'S Portable Crusher**

- 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:** Fong Daniel P S → Fong'S Portable Crusher; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Fong Construction Company Ltd → Fong'S Portable Crusher; 1991-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fong Daniel P S → Fong Construction Company Ltd; 1991-04-01 to current/open; source msha-controller-operator-history