# Relationship history for MSHA mine 2402198

Current hierarchy: **W Greg  Harding → Mission Valley Concrete Industries Inc → PORTABLE CRUSHER**

- 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:** W Greg  Harding → PORTABLE CRUSHER; 1978-03-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mission Valley Concrete Industries Inc → PORTABLE CRUSHER; 2000-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** W Greg  Harding → Mission Valley Concrete Industries Inc; 2000-06-01 to current/open; source msha-controller-operator-history