Foreign persons with a U.S. trade or business, including but not limited to:

• U.S. trade or business;
• Partnerships and trusts;
• Banking;
• Management of real property;
• Determining effectively connected income;
• Effect of tax treaty provisions;
• Permanent establishment; and
• Branch profits tax.

Foreign persons with nonbusiness U.S. source income, including but not limited to:

• General withholding rules, subject to treaties;
• Fixed or determinable annual or periodic (FDAP) income;
• Treaty shopping, and defenses to treaty shopping;
• Responsibilities of withholding agents; and
• Foreign investment in U.S. real property (FIRPTA).