http://www.irs.gov/Individuals/International-Taxpayers/Some-Nonresidents-with-U.S.-Assets-Must-File-Estate-Tax-Returns
Executors for nonresidents must file an estate tax return, Form 706NA, United States Estate (and Generation-Skipping) Tax Return, Estate of a nonresident not a citizen of the United States, if the fair market value at death of the decedent's U.S.-situated assets exceeds $60,000.
Executors for nonresidents must file an estate tax return, Form 706NA, United States Estate (and Generation-Skipping) Tax Return, Estate of a nonresident not a citizen of the United States, if the fair market value at death of the decedent's U.S.-situated assets exceeds $60,000.