# Relationship history for MSHA mine 0400156

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials, Inc. → NATIVIDAD 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:** Martin Marietta Materials Inc → NATIVIDAD PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kaiser Aluminum & Chemical Corp → NATIVIDAD PLANT; 1950-01-01 to 1984-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Kaiser Aluminum & Chemical Corp → NATIVIDAD PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kaiser Aluminum & Chemical Corp → Kaiser Aluminum & Chemical Corp; 1950-01-01 to 1984-12-31; source msha-controller-operator-history
- **operator_operates_mine:** National Refractories & Minerals Corp → NATIVIDAD PLANT; 1985-01-01 to 1997-12-30; source msha-controller-operator-history
- **controller_controls_mine:** National Refractories & Minerals Corp → NATIVIDAD PLANT; 1985-01-01 to 1997-12-30; source msha-controller-operator-history
- **controller_controls_operator:** National Refractories & Minerals Corp → National Refractories & Minerals Corp; 1985-01-01 to 1997-12-30; source msha-controller-operator-history
- **controller_controls_mine:** Chemical Lime Company → NATIVIDAD PLANT; 1986-12-04 to 1998-12-30; source msha-controller-operator-history
- **operator_operates_mine:** Lhoist North America of Arizona Inc. → NATIVIDAD PLANT; 1997-12-31 to 2026-09-16; source msha-controller-operator-history
- **controller_controls_operator:** Chemical Lime Company → Lhoist North America of Arizona Inc.; 1997-12-31 to 1998-12-30; source msha-controller-operator-history
- **controller_controls_mine:** Lhoist Group → NATIVIDAD PLANT; 1998-12-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lhoist Group → Lhoist North America of Arizona Inc.; 1998-12-31 to 2026-09-16; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc. → NATIVIDAD PLANT; 2026-09-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc.; 2026-09-17 to current/open; source msha-controller-operator-history