# Relationship history for MSHA mine 4403784

Current hierarchy: **Roberts Joe H → Joe H Roberts Company → No 2 Strip**

- 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

- **operator_operates_mine:** Joe H Roberts Company → No 2 Strip; 1974-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roberts Joe H → No 2 Strip; 1974-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roberts Joe H → Joe H Roberts Company; 1974-01-01 to current/open; source msha-controller-operator-history