# Relationship history for MSHA mine 2401521

Current hierarchy: **Nicor Minerals Inc → Montana Barite Company → Kenelty Mine**

- 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:** Reber D L → Kenelty Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Montana Barite Company Inc → Kenelty Mine; 1980-02-01 to 1983-07-11; source msha-controller-operator-history
- **controller_controls_operator:** Reber D L → Montana Barite Company Inc; 1980-02-01 to 1983-07-11; source msha-controller-operator-history
- **operator_operates_mine:** Montana Barite Company → Kenelty Mine; 1983-07-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Nicor Minerals Inc → Kenelty Mine; 1983-07-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nicor Minerals Inc → Montana Barite Company; 1983-07-12 to current/open; source msha-controller-operator-history