# Relationship history for MSHA mine 1400081

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Aggregates → #383 Woodbine 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Hallett Construction Company → #383 Woodbine Quarry; 1950-01-01 to 1986-10-13; source msha-controller-operator-history
- **controller_controls_mine:** Hallett Construction Company → #383 Woodbine Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hallett Construction Company → Hallett Construction Company; 1950-01-01 to 1986-10-13; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → #383 Woodbine Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mid America Materials Company → #383 Woodbine Quarry; 1986-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hallett Materials → #383 Woodbine Quarry; 1986-10-14 to 1990-01-14; source msha-controller-operator-history
- **controller_controls_operator:** Mid America Materials Company → Hallett Materials; 1986-10-14 to 1990-01-14; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → #383 Woodbine Quarry; 1990-01-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1990-01-15 to current/open; source msha-controller-operator-history