# Relationship history for MSHA mine 1401548

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Aggregates → MELVERN QUARRY #349**

- 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 → MELVERN QUARRY #349; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Criqui Limestone Inc → MELVERN QUARRY #349; 1991-04-01 to 1996-09-18; source msha-controller-operator-history
- **controller_controls_mine:** Terry  Criqui → MELVERN QUARRY #349; 1991-04-01 to 1996-09-18; source msha-controller-operator-history
- **controller_controls_operator:** Terry  Criqui → Criqui Limestone Inc; 1991-04-01 to 1996-09-18; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → MELVERN QUARRY #349; 1996-09-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1996-09-19 to current/open; source msha-controller-operator-history