# Relationship history for MSHA mine 1200002

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials Inc → North Indianapolis Quarry & Mill**

- 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

- **operator_operates_mine:** American Aggregates Corp → North Indianapolis Quarry & Mill; 1950-01-01 to 1987-02-28; source msha-controller-operator-history
- **controller_controls_mine:** American Aggregates Corp → North Indianapolis Quarry & Mill; 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:** Martin Marietta Materials Inc → North Indianapolis Quarry & Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Consolidated Gold Fields Limited → North Indianapolis Quarry & Mill; 1987-02-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → North Indianapolis Quarry & Mill; 1987-03-01 to 1989-08-06; source msha-controller-operator-history
- **controller_controls_operator:** Consolidated Gold Fields Limited → American Aggregates Corp; 1987-03-01 to 1989-08-06; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → North Indianapolis Quarry & Mill; 1989-03-10 to 1990-02-01; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → North Indianapolis Quarry & Mill; 1989-08-07 to 1990-02-01; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → American Aggregates Corp; 1989-08-07 to 1990-02-01; source msha-controller-operator-history
- **operator_operates_mine:** American Aggregates Corp → North Indianapolis Quarry & Mill; 1990-02-02 to 1997-05-27; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → North Indianapolis Quarry & Mill; 1990-02-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → American Aggregates Corp; 1990-02-02 to 1997-05-27; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → North Indianapolis Quarry & Mill; 1997-05-28 to 2005-05-19; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1997-05-28 to 2005-05-19; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Inc → North Indianapolis Quarry & Mill; 2005-05-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Inc; 2005-05-20 to current/open; source msha-controller-operator-history