# Relationship history for MSHA mine 3608630

Current hierarchy: **Jerry L  Johnson → Johnson Quarries Inc → Cobbs Corner 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:** Robert J  Johnson Sr → Cobbs Corner Quarry; 1987-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jerry L  Johnson → Cobbs Corner Quarry; 1997-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Belcher & Sons Flagstone → Cobbs Corner Quarry; 1997-04-01 to 2002-05-13; source msha-controller-operator-history
- **controller_controls_mine:** Tony  Belcher → Cobbs Corner Quarry; 1997-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tony  Belcher → Belcher & Sons Flagstone; 1997-04-01 to 2002-05-13; source msha-controller-operator-history
- **operator_operates_mine:** ROBERT JOHNSON FLAGSTONE → Cobbs Corner Quarry; 2002-05-14 to 2009-11-22; source msha-controller-operator-history
- **controller_controls_operator:** Robert J  Johnson Sr → ROBERT JOHNSON FLAGSTONE; 2002-05-14 to 2009-11-22; source msha-controller-operator-history
- **operator_operates_mine:** Johnson Quarries Inc → Cobbs Corner Quarry; 2009-11-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jerry L  Johnson → Johnson Quarries Inc; 2009-11-23 to current/open; source msha-controller-operator-history