# Relationship history for MSHA mine 2501103

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials → Springfield 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:** Martin Marietta Materials Inc → Springfield Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** City Wide Rock & Excavating Inc → Springfield Quarry; 1950-01-01 to 2002-07-16; source msha-controller-operator-history
- **operator_operates_mine:** City Wide Rock & Excavating Company Inc → Springfield Quarry; 1988-07-01 to 2001-09-11; source msha-controller-operator-history
- **controller_controls_operator:** City Wide Rock & Excavating Inc → City Wide Rock & Excavating Company Inc; 1988-07-01 to 2001-09-11; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → Springfield Quarry; 2001-09-12 to 2002-07-16; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 2001-09-12 to 2002-07-16; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Springfield Quarry; 2002-07-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → City Wide Rock & Excavating Company Inc; 2002-07-17 to 2001-09-11; source msha-controller-operator-history
- **operator_operates_mine:** City Wide Rock & Excavating → Springfield Quarry; 2002-07-17 to 2002-12-14; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → City Wide Rock & Excavating; 2002-07-17 to 2002-12-14; source msha-controller-operator-history
- **controller_controls_operator:** City Wide Rock & Excavating Inc → City Wide Rock & Excavating; 2002-07-17 to 2002-07-16; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials → Springfield Quarry; 2002-12-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials; 2002-12-15 to current/open; source msha-controller-operator-history