# Relationship history for MSHA mine 1601382

Current hierarchy: **Martin Marietta Materials Inc → TXI Operations LP → Stanley Hornsby Dredge &Plant**

- 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

- **controller_controls_mine:** Texas Industries Inc → Stanley Hornsby Dredge &Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Texas Industries → Stanley Hornsby Dredge &Plant; 2001-03-01 to 2004-12-14; source msha-controller-operator-history
- **controller_controls_operator:** Texas Industries Inc → Texas Industries; 2001-03-01 to 2004-12-14; source msha-controller-operator-history
- **controller_controls_mine:** Texas Industries Inc → Stanley Hornsby Dredge &Plant; 2004-12-01 to 2014-07-01; source msha-controller-operator-history
- **operator_operates_mine:** TXI Operations LP → Stanley Hornsby Dredge &Plant; 2004-12-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Texas Industries Inc → TXI Operations LP; 2004-12-15 to 2014-07-01; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Stanley Hornsby Dredge &Plant; 2014-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → TXI Operations LP; 2014-07-02 to current/open; source msha-controller-operator-history