# Relationship history for MSHA mine 0503552

Current hierarchy: **Bradbury Edward Sr & Thomas → Bemmco → Yankee Blade #3 Shaft**

- 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:** Bemmco → Yankee Blade #3 Shaft; 1983-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bradbury Edward Sr & Thomas Et Al → Yankee Blade #3 Shaft; 1983-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bradbury Edward Sr & Thomas Et Al → Bemmco; 1983-04-01 to current/open; source msha-controller-operator-history