# Relationship history for MSHA mine 4102673

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials Southwest Ltd → PORTER MOORE PIT**

- 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

- **operator_operates_mine:** South Texas Construction Company → PORTER MOORE PIT; 1950-01-01 to 1987-08-05; source msha-controller-operator-history
- **controller_controls_mine:** Basic Industries Inc → PORTER MOORE PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Basic Industries Inc → South Texas Construction Company; 1950-01-01 to 1987-08-05; source msha-controller-operator-history
- **controller_controls_mine:** Redland Plc → PORTER MOORE PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Redland Stone Products Company → PORTER MOORE PIT; 1987-08-06 to 1998-02-10; source msha-controller-operator-history
- **controller_controls_operator:** Redland Plc → Redland Stone Products Company; 1987-08-06 to 1998-02-10; source msha-controller-operator-history
- **operator_operates_mine:** Redland Stone Products Company → PORTER MOORE PIT; 1998-02-11 to 1998-12-16; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → PORTER MOORE PIT; 1998-02-11 to 1998-12-16; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Redland Stone Products Company; 1998-02-11 to 1998-12-16; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Southwest Ltd → PORTER MOORE PIT; 1998-12-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → PORTER MOORE PIT; 1998-12-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Southwest Ltd; 1998-12-17 to current/open; source msha-controller-operator-history