# Relationship history for MSHA mine 4503651

Current hierarchy: **Michael  G  Woolsey → Landworks Northwest Inc. → Portable 4242SR Impactor**

- 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:** Michael  G  Woolsey → Portable 4242SR Impactor; 1995-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Landworks Northwest Inc → Portable 4242SR Impactor; 2008-09-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  G  Woolsey → Landworks Northwest Inc; 2008-09-15 to current/open; source msha-controller-operator-history