# Relationship history for MSHA mine 4406447

Current hierarchy: **Koch Industries Inc → Koch Carbon Inc → Tl No 1 Strip**

- 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:** Koch Industries Inc → Tl No 1 Strip; 1979-05-31 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Koch Carbon Inc → Tl No 1 Strip; 1988-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Koch Industries Inc → Koch Carbon Inc; 1988-03-01 to current/open; source msha-controller-operator-history