# Relationship history for MSHA mine 1200003

Current hierarchy: **Rogers Group Inc → Rogers Group Inc → Spencer 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

- **operator_operates_mine:** American Aggregates Corp → Spencer Quarry; 1950-01-01 to 1987-02-28; source msha-controller-operator-history
- **controller_controls_mine:** American Aggregates Corp → Spencer Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** American Aggregates Corp → American Aggregates Corp; 1950-01-01 to 1987-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Rogers Group Inc → Spencer Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Consolidated Gold Fields Limited → Spencer Quarry; 1987-02-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → Spencer Quarry; 1987-03-01 to 1989-05-01; source msha-controller-operator-history
- **controller_controls_operator:** Consolidated Gold Fields Limited → American Aggregates Corp; 1987-03-01 to 1989-05-01; source msha-controller-operator-history
- **operator_operates_mine:** Rogers Group Inc → Spencer Quarry; 1989-05-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rogers Group Inc → Rogers Group Inc; 1989-05-02 to current/open; source msha-controller-operator-history