# Relationship history for MSHA mine 2103103

Current hierarchy: **Kevin D  Scherber → Hassan Sand & Gravel, Inc. → HSAG #1**

- 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:** Hassan Sand & Gravel, Inc. → HSAG #1; 1995-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dale  Scherber → HSAG #1; 1995-06-01 to 2019-01-02; source msha-controller-operator-history
- **controller_controls_operator:** Dale  Scherber → Hassan Sand & Gravel, Inc.; 1995-06-01 to 2019-01-02; source msha-controller-operator-history
- **controller_controls_mine:** Kevin D  Scherber et al → HSAG #1; 2019-01-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kevin D  Scherber et al → Hassan Sand & Gravel, Inc.; 2019-01-03 to current/open; source msha-controller-operator-history