# Relationship history for MSHA mine 3901591

Current hierarchy: **Leonard  Matthaei; DeeAnn  Matthaei → Matthaei Excavating Inc → Portable Screener #2**

- 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

- **controller_controls_mine:** Leonard  Matthaei et al → Portable Screener #2; 2008-08-11 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Matthaei Excavating Inc → Portable Screener #2; 2012-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Leonard  Matthaei et al → Matthaei Excavating Inc; 2012-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** DeeAnn  Matthaei et al → Matthaei Excavating Inc; 2012-08-28 to current/open; source msha-controller-operator-history