# Relationship history for MSHA mine 4103905

Current hierarchy: **MDU Resources Group Inc → Young Materials Corp → COBB 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

- **controller_controls_mine:** F M  Young → COBB PIT; 1950-01-01 to 2003-07-10; source msha-controller-operator-history
- **operator_operates_mine:** Young Materials Corp → COBB PIT; 1995-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** F M  Young → Young Materials Corp; 1995-06-01 to 2003-07-10; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → COBB PIT; 2003-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Young Materials Corp; 2003-07-11 to current/open; source msha-controller-operator-history