# Relationship history for MSHA mine 1202203

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials Inc → Kokomo Sand**

- 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:** Martin Marietta Materials Inc → Kokomo Sand; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → Kokomo Sand; 1996-11-01 to 2002-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1996-11-01 to 2002-06-03; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Incorporated → Kokomo Sand; 2002-06-04 to 2003-02-20; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Incorporated; 2002-06-04 to 2003-02-20; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → Kokomo Sand; 2003-02-21 to 2005-05-19; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 2003-02-21 to 2005-05-19; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Inc → Kokomo Sand; 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