# Relationship history for MSHA mine 0301731

Current hierarchy: **Daryl  Jackson → Rock Producers Inc → Alma Quarry**

- 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:** Daryl  Jackson → Alma Quarry; 1988-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Rock Producers Inc → Alma Quarry; 1992-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daryl  Jackson → Rock Producers Inc; 1992-09-01 to current/open; source msha-controller-operator-history