# Relationship history for MSHA mine 2103326

Current hierarchy: **Central Specialties, Inc. → Central Specialties, Inc. → SAND SCREW**

- 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:** Joe  Minnerath et al → SAND SCREW; 1997-04-01 to 2021-01-05; source msha-controller-operator-history
- **operator_operates_mine:** Central Specialties, Inc. → SAND SCREW; 2002-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joe  Minnerath et al → Central Specialties, Inc.; 2002-07-01 to 2021-01-05; source msha-controller-operator-history
- **controller_controls_mine:** Allan  Minnerath → SAND SCREW; 2021-01-06 to 2024-01-01; source msha-controller-operator-history
- **controller_controls_operator:** Allan  Minnerath → Central Specialties, Inc.; 2021-01-06 to 2024-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Central Specialties, Inc. → SAND SCREW; 2024-01-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Central Specialties, Inc. → Central Specialties, Inc.; 2024-01-02 to current/open; source msha-controller-operator-history