# Relationship history for MSHA mine 3502906

Current hierarchy: **Knife River Corporation → Knife River Materials → Mobile 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

- **controller_controls_mine:** Charles W  Royers → Mobile Crusher #1; 1978-03-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Charles Royers Company → Mobile Crusher #1; 1979-01-01 to 1990-08-26; source msha-controller-operator-history
- **controller_controls_operator:** Charles W  Royers → Charles Royers Company; 1979-01-01 to 1990-08-26; source msha-controller-operator-history
- **operator_operates_mine:** Bracelin-Yeager Div. of LTM Inc. → Mobile Crusher #1; 1990-08-27 to 2001-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Leroy  Bracelin  et al → Mobile Crusher #1; 1990-08-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Leroy  Bracelin  et al → Bracelin-Yeager Div. of LTM Inc.; 1990-08-27 to 2001-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Irv  Yeager  et al → Bracelin-Yeager Div. of LTM Inc.; 1990-08-27 to 2001-09-30; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → Mobile Crusher #1; 2000-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bracelin-Yeager Umpqua River Navigation → Mobile Crusher #1; 2001-10-01 to 2007-07-02; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Bracelin-Yeager Umpqua River Navigation; 2001-10-01 to 2007-07-02; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → Mobile Crusher #1; 2004-05-28 to 2023-05-31; source msha-controller-operator-history
- **operator_operates_mine:** Knife River Materials → Mobile Crusher #1; 2007-07-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Knife River Materials; 2007-07-03 to 2023-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Knife River Corporation → Mobile Crusher #1; 2023-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Knife River Corporation → Knife River Materials; 2023-06-01 to current/open; source msha-controller-operator-history