# Relationship history for MSHA mine 1100549

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Aggregates → PANA 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

- **controller_controls_mine:** Martin Marietta Materials Inc → PANA QUARRY; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** St Louis Slag Products → PANA QUARRY; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Standard Slag Company → PANA QUARRY; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Standard Slag Company → St Louis Slag Products; 1950-01-01 to 1989-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Standard Lafarge → PANA QUARRY; 1989-10-01 to 1993-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → PANA QUARRY; 1989-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Standard Lafarge; 1989-10-01 to 1993-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → PANA QUARRY; 1994-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1994-01-01 to current/open; source msha-controller-operator-history