# Relationship history for MSHA mine 0600636

Current hierarchy: **O & G Industries Inc → O & G INDUSTRIES INC → NEW MILFORD PLANT**

- 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:** O & G Industries Inc → NEW MILFORD PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Advance Stone Inc → NEW MILFORD PLANT; 1990-10-01 to 2006-08-01; source msha-controller-operator-history
- **controller_controls_mine:** Paul  Kovacs  et al → NEW MILFORD PLANT; 1990-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Paul  Kovacs  et al → Advance Stone Inc; 1990-10-01 to 2006-08-01; source msha-controller-operator-history
- **controller_controls_operator:** Roger  Kovacs  et al → Advance Stone Inc; 1990-10-01 to 2006-08-01; source msha-controller-operator-history
- **operator_operates_mine:** O & G Industries Inc → NEW MILFORD PLANT; 2006-08-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** O & G Industries Inc → O & G Industries Inc; 2006-08-02 to current/open; source msha-controller-operator-history