# Relationship history for MSHA mine 2301913

Current hierarchy: **Rasmussen Group Inc → Viking Aggregates, Inc. → Kahoka Crushing Plant**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Kaser Corporation et al → Kahoka Crushing Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kaser Corp → Kahoka Crushing Plant; 1985-05-01 to 1995-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Kaser Corporation et al → Kaser Corp; 1985-05-01 to 1995-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc et al → Kaser Corp; 1985-05-01 to 1995-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Johnson Holding Company → Kahoka Crushing Plant; 1991-03-15 to 2024-04-18; source msha-controller-operator-history
- **operator_operates_mine:** Viking Aggregates, Inc. → Kahoka Crushing Plant; 1995-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnson Holding Company → Viking Aggregates, Inc.; 1995-05-01 to 2024-04-18; source msha-controller-operator-history
- **controller_controls_mine:** Rasmussen Group Inc → Kahoka Crushing Plant; 2024-04-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rasmussen Group Inc → Viking Aggregates, Inc.; 2024-04-19 to current/open; source msha-controller-operator-history