# Relationship history for MSHA mine 4703431

Current hierarchy: **Michael  Bakken; Richard  Bakken → Northwestern Stone LLC → Plant #4**

- 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

- **controller_controls_mine:** Richard C  Bakken → Plant #4; 1950-01-01 to 2025-03-26; source msha-controller-operator-history
- **operator_operates_mine:** Northwestern Stone LLC → Plant #4; 2005-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard C  Bakken → Northwestern Stone LLC; 2005-07-19 to 2025-03-26; source msha-controller-operator-history
- **controller_controls_mine:** Michael  Bakken et al → Plant #4; 2025-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  Bakken et al → Northwestern Stone LLC; 2025-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Bakken et al → Northwestern Stone LLC; 2025-03-27 to current/open; source msha-controller-operator-history