I have question for fellow developers who reside in a country which has tax treaty agreements with US that has 0% withholding rates for royalty payments. Is Amazon withholding the 30% from your payments if you have not supplied ITIN? As Amazon Tax Interview says that to get treaty benefits, you must have ITIN even if your country has treaty with US with 0% withholding.
We address this question in our Distribution Portal FAQs, in the section
https://developer.amazon.com/help/faq.html#SalesPaymentTax, under the question Q: Will you withhold any taxes from payments made to international developers for U.S. sales? If you have additional questions with regard to tax withholding for the Amazon Mobile App Distribution Program, please use our Contact Us feature for help from the Mobile App Distribution Support Team.