# Relationship history for MSHA mine 4300666

Current hierarchy: **Greg D  Tatro → G W Tatro Construction Co Inc → Powerscreen Powertrack 800**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Greg D  Tatro → Powerscreen Powertrack 800; 1989-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** G W Tatro Construction Co Inc → Powerscreen Powertrack 800; 2007-06-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greg D  Tatro → G W Tatro Construction Co Inc; 2007-06-12 to current/open; source msha-controller-operator-history