# Relationship history for MSHA mine 0405400

Current hierarchy: **Chul L  Choe → Protech Minerals Inc → BROWN CLAY**

- 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:** Chul L  Choe → BROWN CLAY; 1996-01-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Protech Minerals Inc → BROWN CLAY; 2000-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Chul L  Choe → Protech Minerals Inc; 2000-01-01 to current/open; source msha-controller-operator-history