# Relationship history for MSHA mine 4400067

Current hierarchy: **Roy D  Simmons Jr → Rockbridge Stone Products Inc → 01 MINE**

- 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:** Lone Jack Limestone Company Inc → 01 MINE; 1950-01-01 to 1993-01-18; source msha-controller-operator-history
- **controller_controls_mine:** Robert W  Massie III → 01 MINE; 1950-01-01 to 1993-01-18; source msha-controller-operator-history
- **controller_controls_operator:** Robert W  Massie III → Lone Jack Limestone Company Inc; 1950-01-01 to 1993-01-18; source msha-controller-operator-history
- **operator_operates_mine:** Rockbridge Stone Products Inc → 01 MINE; 1993-01-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy D  Simmons Jr → 01 MINE; 1993-01-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy D  Simmons Jr → Rockbridge Stone Products Inc; 1993-01-19 to current/open; source msha-controller-operator-history