# Relationship history for MSHA mine 2601966

Current hierarchy: **Fred  Ketten → Ketten Enterprises Inc → Tonopah Sand & Gravel #2**

- 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:** Fred  Ketten → Tonopah Sand & Gravel #2; 1985-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ketten Enterprises Inc → Tonopah Sand & Gravel #2; 1986-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fred  Ketten → Ketten Enterprises Inc; 1986-06-01 to current/open; source msha-controller-operator-history