# Relationship history for MSHA mine 4104163

Current hierarchy: **Rocky  York; Byron  York → York Brothers Stone Company → YORK BROS 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:** York Brothers Stone Company → YORK BROS QUARRY; 2000-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Rocky  York et al → YORK BROS QUARRY; 2000-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rocky  York et al → York Brothers Stone Company; 2000-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Byron  York et al → York Brothers Stone Company; 2000-06-01 to current/open; source msha-controller-operator-history