# Relationship history for MSHA mine 2601698

Current hierarchy: **Block Gerald & Bernard Klein → Stewart Kelly Mine (Mdi) → Stewart Kelly 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

- **operator_operates_mine:** Stewart Kelly Mine (Mdi) → Stewart Kelly Mine; 1980-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Block Gerald & Bernard Klein Et Al → Stewart Kelly Mine; 1980-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Block Gerald & Bernard Klein Et Al → Stewart Kelly Mine (Mdi); 1980-12-01 to current/open; source msha-controller-operator-history