Quote from alanm:
Since you say "prop firms", do you really mean "customer"? That is, are you a member/partner in an LLC, getting a partnership income K1 form at the end of the year, instead of a 1099?
Let's suppose there is a trader from Europe who has Series 7 and opens prop accout(with deposit) at Assent/Bright/Echo/Genesis and etc.
What tax from will he receive at the end of the year?