Related persons is any of the following:
- Members of a family, including only brothers, sisters, half brothers, half sisters, spouse, ancestors (parents, grandparents, etc.), and lineal descendants (children, grandchildren, etc.).
- Any person who is a party to any arrangement undertaken for the purpose of avoiding the contingent interest rules.
- Certain corporations, partnerships, and other entities.
Citation: IRC § 871(h)(4)(B). Tax on nonresident alien individuals