# Relationship history for MSHA mine 1400839

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta-Basic Products Aggregate Div → Flory 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

- **operator_operates_mine:** Martin Marietta-Basic Products Aggregate Div → Flory Quarry; 1984-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Flory Quarry; 1984-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta-Basic Products Aggregate Div; 1984-05-01 to current/open; source msha-controller-operator-history