A friend of mine is a U.S. citizen in South Korea who made some money trading South Korean stocks through a South Korean brokerage company. Is he going to have to pay U.S. capital gains taxes on his profit? Does anyone know of a good accountant that can handle taxes on trading foreign stocks?
US citizens are subject to US income tax on their worldwide income from all sources. Where you, er, you friend, are, what country's stocks you trade and through whom, are all moot points. There is no special "handling" involved in this case. Any tax accountant or tax prep software can handle this.