# Relationship history for MSHA mine 2002866

Current hierarchy: **Daniel R  Balkema; Ralph T  Balkema → Balkema Inc → Finlay Construction**

- 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:** Balkema Inc → Finlay Construction; 1991-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Daniel R  Balkema et al → Finlay Construction; 1991-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daniel R  Balkema et al → Balkema Inc; 1991-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ralph T  Balkema et al → Balkema Inc; 1991-08-01 to current/open; source msha-controller-operator-history