# Relationship history for MSHA mine 3605633

Current hierarchy: **Gregory F E Jr → F E Gregory & Sons Inc → F E Gregory**

- 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:** F E Gregory & Sons Inc → F E Gregory; 1975-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gregory F E Jr → F E Gregory; 1975-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gregory F E Jr → F E Gregory & Sons Inc; 1975-06-01 to current/open; source msha-controller-operator-history