# Relationship history for MSHA mine 2301924

Current hierarchy: **CRH PLC → Ash Grove Aggregates Inc → RENTAL PLANT PORTABLE**

- 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:** Ash Grove Cement Company → RENTAL PLANT PORTABLE; 1950-01-01 to 2018-06-20; source msha-controller-operator-history
- **operator_operates_mine:** Fort Scott Fertilizer - Cullor Inc → RENTAL PLANT PORTABLE; 1985-07-01 to 1993-05-20; source msha-controller-operator-history
- **controller_controls_mine:** Gary W  Cullor → RENTAL PLANT PORTABLE; 1985-07-01 to 1993-05-20; source msha-controller-operator-history
- **controller_controls_operator:** Gary W  Cullor → Fort Scott Fertilizer - Cullor Inc; 1985-07-01 to 1993-05-20; source msha-controller-operator-history
- **operator_operates_mine:** Ash Grove Aggregates Inc → RENTAL PLANT PORTABLE; 1993-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ash Grove Cement Company → Ash Grove Aggregates Inc; 1993-05-21 to 2018-06-20; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → RENTAL PLANT PORTABLE; 2018-06-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Ash Grove Aggregates Inc; 2018-06-21 to current/open; source msha-controller-operator-history