U.S. companies that are 25 percent or more foreign-owned, foreign companies that are engaged in business with the U.S., and certain other multinationals must file a Form 5472 with their corporate U.S. tax return if they engage in a reportable transaction. The form isn't new, but related reporting requirements and penalties have been expanded.
If you’re a U.S. taxpayer with a bank account outside the country, you may need file an FBAR, which is used to report foreign account information to the U.S. government. Failure to file can result in severe penalties, with fines as high as $100,000 or 50% of the account's balance.