# Relationship history for MSHA mine 2300181

Current hierarchy: **John H Berra Construction Co → Riverview Quarry Inc → Riverview Quarry Incorporated (North)**

- 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

- **operator_operates_mine:** Riverview Stone & Material Company → Riverview Quarry Incorporated (North); 1950-01-01 to 1987-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Meyer R W → Riverview Quarry Incorporated (North); 1950-01-01 to 1987-01-01; source msha-controller-operator-history
- **controller_controls_operator:** Meyer R W → Riverview Stone & Material Company; 1950-01-01 to 1987-01-01; source msha-controller-operator-history
- **operator_operates_mine:** Riverview Quarry Inc → Riverview Quarry Incorporated (North); 1987-01-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John H Berra Construction Co → Riverview Quarry Incorporated (North); 1987-01-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John H Berra Construction Co → Riverview Quarry Inc; 1987-01-02 to current/open; source msha-controller-operator-history