# Relationship history for MSHA mine 0400011

Current hierarchy: **Taiheiyo Cement Corp → CALPORTLAND → ORO GRANDE 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:** Amcord Inc → ORO GRANDE QUARRY; 1950-01-01 to 1979-12-06; source msha-controller-operator-history
- **operator_operates_mine:** Riverside Cement Company → ORO GRANDE QUARRY; 1978-03-09 to 1979-12-06; source msha-controller-operator-history
- **controller_controls_operator:** Amcord Inc → Riverside Cement Company; 1978-03-09 to 1979-12-06; source msha-controller-operator-history
- **operator_operates_mine:** Riverside Cement Company → ORO GRANDE QUARRY; 1979-12-07 to 1995-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → ORO GRANDE QUARRY; 1979-12-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Riverside Cement Company; 1979-12-07 to 1995-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Taiheiyo Cement Corp → ORO GRANDE QUARRY; 1990-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Riverside Cement Company → ORO GRANDE QUARRY; 1995-02-01 to 1998-01-14; source msha-controller-operator-history
- **controller_controls_mine:** Ssangyong Corp → ORO GRANDE QUARRY; 1995-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ssangyong Corp → Riverside Cement Company; 1995-02-01 to 1998-01-14; source msha-controller-operator-history
- **operator_operates_mine:** Riverside Cement Co → ORO GRANDE QUARRY; 1998-01-15 to 2015-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Texas Industries Inc → ORO GRANDE QUARRY; 1998-01-15 to 2014-07-01; source msha-controller-operator-history
- **controller_controls_operator:** Texas Industries Inc → Riverside Cement Co; 1998-01-15 to 2014-07-01; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → ORO GRANDE QUARRY; 2014-07-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Riverside Cement Co; 2014-07-02 to 2015-09-30; source msha-controller-operator-history
- **operator_operates_mine:** CalPortland → ORO GRANDE QUARRY; 2015-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Taiheiyo Cement Corp → CalPortland; 2015-10-01 to current/open; source msha-controller-operator-history