# Relationship history for MSHA mine 3200874

Current hierarchy: **Clifford H  Sabo; Julie  Dahl-Sabo → J. D. Services Inc → Portable Crusher #1**

- 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:** J. D. Services Inc → Portable Crusher #1; 2010-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Julie  Dahl-Sabo et al → Portable Crusher #1; 2010-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Julie  Dahl-Sabo et al → J. D. Services Inc; 2010-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Clifford H  Sabo et al → J. D. Services Inc; 2010-11-16 to current/open; source msha-controller-operator-history