# Relationship history for MSHA mine 0500344

Current hierarchy: **Cemex S A → CEMEX Construction Materials South, LLC → Lyons Cement Plant Cemex Inc**

- 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:** Martin Marietta Cement → Lyons Cement Plant Cemex Inc; 1950-01-01 to 1984-04-02; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Lyons Cement Plant Cemex Inc; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Cement; 1950-01-01 to 1984-04-02; source msha-controller-operator-history
- **controller_controls_mine:** Southdown Inc → Lyons Cement Plant Cemex Inc; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southdown Inc → Lyons Cement Plant Cemex Inc; 1984-04-03 to 2001-02-27; source msha-controller-operator-history
- **controller_controls_operator:** Southdown Inc → Southdown Inc; 1984-04-03 to 2001-02-27; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Lyons Cement Plant Cemex Inc; 1994-09-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cemex Inc → Lyons Cement Plant Cemex Inc; 2001-02-28 to 2015-07-21; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Cemex Inc; 2001-02-28 to 2015-07-21; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Lyons Cement Plant Cemex Inc; 2008-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** CEMEX Construction Materials South, LLC → Lyons Cement Plant Cemex Inc; 2015-07-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → CEMEX Construction Materials South, LLC; 2015-07-22 to current/open; source msha-controller-operator-history