# Relationship history for MSHA mine 3500856

Current hierarchy: **Parks & Palm Logging Company → Parks & Palm Logging Company → Clatskanie Quarry**

- 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:** Parks & Palm Logging Company → Clatskanie Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Parks & Palm Logging Company → Clatskanie Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Parks & Palm Logging Company → Parks & Palm Logging Company; 1950-01-01 to current/open; source msha-controller-operator-history