# Relationship history for MSHA mine 0401699

Current hierarchy: **Knife River Corporation → Baldwin Contracting Company Inc → Pentz Pit**

- 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:** Baldwin Contracting Company Inc → Pentz Pit; 1950-01-01 to 1996-07-31; source msha-controller-operator-history
- **controller_controls_mine:** M & T Inc → Pentz Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** M & T Inc → Baldwin Contracting Company Inc; 1950-01-01 to 1996-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Baldwin Contracting Company Inc → Pentz Pit; 1996-08-01 to 1997-02-09; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → Pentz Pit; 1996-08-01 to 2023-05-31; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Baldwin Contracting Company Inc; 1996-08-01 to 1997-02-09; source msha-controller-operator-history
- **operator_operates_mine:** Aggregate Material Processing Inc → Pentz Pit; 1997-02-10 to 1999-02-08; source msha-controller-operator-history
- **controller_controls_mine:** Randy J  Howarth  et al → Pentz Pit; 1997-02-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Randy J  Howarth  et al → Aggregate Material Processing Inc; 1997-02-10 to 1999-02-08; source msha-controller-operator-history
- **controller_controls_operator:** William I  Sliger  et al → Aggregate Material Processing Inc; 1997-02-10 to 1999-02-08; source msha-controller-operator-history
- **operator_operates_mine:** Baldwin Contracting Company Inc → Pentz Pit; 1999-02-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Baldwin Contracting Company Inc; 1999-02-09 to 2023-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Knife River Corporation → Pentz Pit; 2023-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Knife River Corporation → Baldwin Contracting Company Inc; 2023-06-01 to 1997-02-09; source msha-controller-operator-history
- **controller_controls_operator:** Knife River Corporation → Baldwin Contracting Company Inc; 2023-06-01 to current/open; source msha-controller-operator-history