# Relationship history for MSHA mine 0300509

Current hierarchy: **Ben  Baldwin; Billy C  Baldwin; Brandon  Baldwin → ROCK-IT NATURAL STONE, INC. → Arkansas Sand & Gravel**

- 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:** Ozark Material Company Inc → Arkansas Sand & Gravel; 1950-01-01 to 2013-05-22; source msha-controller-operator-history
- **controller_controls_mine:** Robert N  Chrisman → Arkansas Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert N  Chrisman → Ozark Material Company Inc; 1950-01-01 to 2013-05-22; source msha-controller-operator-history
- **controller_controls_mine:** Billy D  Baldwin → Arkansas Sand & Gravel; 2001-02-01 to 2024-01-22; source msha-controller-operator-history
- **operator_operates_mine:** Arkansas Sand and Gravel, LLC → Arkansas Sand & Gravel; 2013-05-23 to 2014-01-20; source msha-controller-operator-history
- **controller_controls_mine:** Larrisa  Opper → Arkansas Sand & Gravel; 2013-05-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larrisa  Opper → Arkansas Sand and Gravel, LLC; 2013-05-23 to 2014-01-20; source msha-controller-operator-history
- **operator_operates_mine:** ROCK-IT NATURAL STONE, INC. → Arkansas Sand & Gravel; 2014-01-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Billy D  Baldwin → ROCK-IT NATURAL STONE, INC.; 2014-01-21 to 2024-01-22; source msha-controller-operator-history
- **controller_controls_mine:** Ben  Baldwin et al → Arkansas Sand & Gravel; 2024-01-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ben  Baldwin et al → ROCK-IT NATURAL STONE, INC.; 2024-01-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brandon  Baldwin et al → ROCK-IT NATURAL STONE, INC.; 2024-01-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Billy C  Baldwin et al → ROCK-IT NATURAL STONE, INC.; 2024-01-23 to current/open; source msha-controller-operator-history