Do you need to clarify whether you are a "US person"?

This includes Green card holder, resident, snow bird. This is a good site to give clarification. It can be very confusing for many people.

Generally the question of whether one is a “U.S. person” (citizen, Green Card Holder, resident, substantial presence test) is determined under U.S. law. FATCA has the effect of enforcing the taxation of “U.S. persons” who reside outside the U.S. By changing the definition of “U.S. person”, the U.S. can increase the number of “U.S. persons” residing in other countries. FATCA is the enforcer – by identifying “U.S. persons” – of extra-territorial taxation. The combined effect of “U.S. person” taxation and FATCA is that the U.S. can increase or decrease its tax base in other countries. If more people are deemed to be U.S. persons the tax base will increase. The FATCA rules make clear that the U.S. and only the U.S. will define what is a “U.S. account” (held by a “U.S. person”).

Interestingly the IRS has offices outside the U.S. (London, Frankfurt, Paris and Beijing). As FATCA becomes fully operational, one wonders whether the IRS will establish more “Local Office(s) Internationally”. FATCA is likely to make the IRS a “U.S. export”.

The U.S. is gradually expanding the number and kinds of people that it deems to be taxable “U.S. persons”. Leaving aside the question of “citizens”, it’s important to realize that U.S. “residents” (which can include people who do NOT reside in the U.S.) are taxable “U.S. persons”.

For further reading on this article click on link. This link is NOT by a tax compliant accountant /lawyer that wants money to do your taxes. Just ordinary people who live abroad.

http://isaacbrocksociety.ca/2014/11/07/fatca-and-extra-territorial-taxation/#more-33388