# Relationship history for MSHA mine 2103762

Current hierarchy: **Curtis L  Osterfeld → North Central Inc → The Screen Machine**

- 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:** North Central Inc → The Screen Machine; 2012-04-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Curtis L  Osterfeld → The Screen Machine; 2012-04-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Curtis L  Osterfeld → North Central Inc; 2012-04-23 to current/open; source msha-controller-operator-history