Passive income is defined under IRC §1297(b), generally by reference to foreign personal holding company income under IRC §954(c), including dividends, interest, rents, royalties, annuities, and certain gains.
Practical Takeaway
Most PFIC problems for U.S. persons abroad come from ordinary foreign funds, not exotic offshore schemes. Foreign mutual funds, ETFs, managed funds, and pooled investment products commonly hold passive assets and earn passive income, so they often fall within the PFIC definition.