# Relationship history for MSHA mine 4201536

Current hierarchy: **Janice  Sackett; Larry  Jardine → Le Grand Johnson Construction Company → Ferry Sand And Gravel Pit**

- 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

- **controller_controls_mine:** Janice  Sackett et al → Ferry Sand And Gravel Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Le Grand Johnson Construction Company → Ferry Sand And Gravel Pit; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Janice  Sackett et al → Le Grand Johnson Construction Company; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry  Jardine et al → Le Grand Johnson Construction Company; 1978-03-09 to current/open; source msha-controller-operator-history