# Relationship history for MSHA mine 0405140

Current hierarchy: **Knife River Corporation → Knife River → Concrete, Inc DBA Knife River**

- 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:** Roc-San Gravel Company Inc → Concrete, Inc DBA Knife River; 1991-04-01 to 1992-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Gregory  Lewis → Concrete, Inc DBA Knife River; 1991-04-01 to 1992-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Gregory  Lewis → Roc-San Gravel Company Inc; 1991-04-01 to 1992-04-30; source msha-controller-operator-history
- **operator_operates_mine:** KRC Aggregate Inc → Concrete, Inc DBA Knife River; 1992-05-01 to 2010-04-30; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → Concrete, Inc DBA Knife River; 1992-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → KRC Aggregate Inc; 1992-05-01 to 2010-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Knife River → Concrete, Inc DBA Knife River; 2010-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → Concrete, Inc DBA Knife River; 2010-05-01 to 2023-05-31; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Knife River; 2010-05-01 to 2023-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Knife River Corporation → Concrete, Inc DBA Knife River; 2023-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Knife River Corporation → Knife River; 2023-06-01 to current/open; source msha-controller-operator-history