# Relationship history for MSHA mine 0404157

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Southern California Aggregates,LLC → Maitri Sand and Gravel**

- 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:** Chandler'S Palos Verdes Sand & Gravel Company → Maitri Sand and Gravel; 1950-01-01 to 1995-01-06; source msha-controller-operator-history
- **controller_controls_mine:** Linden H  Chandler → Maitri Sand and Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Linden H  Chandler → Chandler'S Palos Verdes Sand & Gravel Company; 1950-01-01 to 1995-01-06; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Maitri Sand and Gravel; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **operator_operates_mine:** Chandler Aggregates Inc → Maitri Sand and Gravel; 1995-01-07 to 2024-10-10; source msha-controller-operator-history
- **controller_controls_mine:** Jim  Broyles et al → Maitri Sand and Gravel; 1995-01-07 to 2017-03-09; source msha-controller-operator-history
- **controller_controls_operator:** Jim  Broyles et al → Chandler Aggregates Inc; 1995-01-07 to 2017-03-09; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Maitri Sand and Gravel; 2007-08-23 to 2021-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Eric  Werner et al → Maitri Sand and Gravel; 2017-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eric  Werner et al → Chandler Aggregates Inc; 2017-03-10 to 2024-10-10; source msha-controller-operator-history
- **controller_controls_operator:** Pat  Broyles et al → Chandler Aggregates Inc; 2017-03-10 to 2024-10-10; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Maitri Sand and Gravel; 2021-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Southern California Aggregates,LLC → Maitri Sand and Gravel; 2024-10-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Martin Marietta Southern California Aggregates,LLC; 2024-10-11 to 2021-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Southern California Aggregates,LLC; 2024-10-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Martin Marietta Southern California Aggregates,LLC; 2024-10-11 to 2007-08-22; source msha-controller-operator-history