Domestic (US) customers receive a 1099 tax statement, which includes dividends, interest, 1099-B, OID, and 1099 miscellaneous. We produce 1099s for domestic accounts with reportable activity, for the 1099-DIV and 1099-INT they would have to receive $10 or more to generate a tax statement and disposition of shares (ie sale, short sale for example) would generate 1099-B.
International users (Non-US) will receive a 1042-S tax statement for all foreign accounts if they have reportable activity. Reportable activity includes dividend income (or MLP dividend income) of $.50 or more for the tax year. This also covers spillover payments. The amount is then rounded to the nearest $1.00. This applies to each income code listed on the form.