# Relationship history for MSHA mine 4104320

Current hierarchy: **Ruben  Perez → R & J Materials → R & J Building Stone 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:** R & J Materials → R & J Building Stone Quarry; 2001-10-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ruben  Perez → R & J Building Stone Quarry; 2001-10-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ruben  Perez → R & J Materials; 2001-10-29 to current/open; source msha-controller-operator-history