# Relationship history for MSHA mine 4000071

Current hierarchy: **Wiley B  Roark → MAYMEAD MATERIALS, INC. → MAYMEAD MATERIALS, INC.**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Maymead Materials, Inc. → MAYMEAD MATERIALS, INC.; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wiley B  Roark et al → MAYMEAD MATERIALS, INC.; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wiley B  Roark et al → Maymead Materials, Inc.; 1950-01-01 to current/open; source msha-controller-operator-history