# Relationship history for MSHA mine 4503364

Current hierarchy: **Cemex S A → Pacific Rock Products LLC → Portable #1**

- 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:** Eucon Corporation → Portable #1; 1985-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Pacific Rock Products Llc → Portable #1; 1997-04-01 to 2000-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Eucon Corporation → Pacific Rock Products Llc; 1997-04-01 to 2000-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Pacific Rock Products LLC → Portable #1; 2000-10-01 to 2002-09-25; source msha-controller-operator-history
- **controller_controls_mine:** Peter Kiewit Sons' Inc → Portable #1; 2000-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Peter Kiewit Sons' Inc → Pacific Rock Products LLC; 2000-10-01 to 2002-09-25; source msha-controller-operator-history
- **operator_operates_mine:** Pacific Rock Products LLC → Portable #1; 2002-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → Portable #1; 2002-09-26 to 2003-03-31; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → Pacific Rock Products LLC; 2002-09-26 to 2003-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Rinker Group Ltd → Portable #1; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Rinker Group Ltd → Pacific Rock Products LLC; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Portable #1; 2007-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Pacific Rock Products LLC; 2007-07-10 to current/open; source msha-controller-operator-history