# Relationship history for MSHA mine 4406135

Current hierarchy: **Walter F  Steele → Riverside Brick & Supply Company → MINE # 4**

- 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:** Riverside Brick & Supply Company → MINE # 4; 1984-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Walter F  Steele et al → MINE # 4; 1984-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walter F  Steele et al → Riverside Brick & Supply Company; 1984-09-01 to current/open; source msha-controller-operator-history