For Milenijski & Cilji, an uncertain tax situation is one involving the revenue earned from any received income from assets or jobs performed outside the USA. These rulings change a lot from state to state. It would be best if you hire someone to handle the way to report this income accurately and avoid any legal issues. If you have real estate properties in other country and you receive income by renting it, the IRA takes a cut. It also happens when you have stock investments that generate revenue outside the USA, Uncle Sam will come to claim its share.