# Relationship history for MSHA mine 4102367

Current hierarchy: **Bobby  Yancey → Conroe Concrete Inc → Yancey Sand & Gravel Pit & Plant**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Conroe Concrete Inc → Yancey Sand & Gravel Pit & Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bobby  Yancey → Yancey Sand & Gravel Pit & Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bobby  Yancey → Conroe Concrete Inc; 1950-01-01 to current/open; source msha-controller-operator-history