# Relationship history for MSHA mine 5400001

Current hierarchy: **Cemex S A → Cemex de Puerto Rico → Ponce Cement 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

- **operator_operates_mine:** Cemex de Puerto Rico → Ponce Cement Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Puerto Rican Cement Company Inc → Ponce Cement Plant; 1950-01-01 to 2002-11-29; source msha-controller-operator-history
- **controller_controls_operator:** Puerto Rican Cement Company Inc → Cemex de Puerto Rico; 1950-01-01 to 2002-11-29; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Ponce Cement Plant; 2002-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Cemex de Puerto Rico; 2002-11-30 to current/open; source msha-controller-operator-history