# Relationship history for MSHA mine 4105543

Current hierarchy: **Dean  Fischer → Brauntex Materials, Inc. → Medina River 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

- **controller_controls_mine:** Dean  Fischer → Medina River Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Brauntex Materials, Inc. → Medina River Sand & Gravel; 2021-01-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dean  Fischer → Brauntex Materials, Inc.; 2021-01-28 to current/open; source msha-controller-operator-history