Hello, I have a puzzling question that I cannot solve.

Situation: LLC single owner.

Should file form 1040NR for ECI or non ECI that is U.S. derived, with certain exceptions.

Product is book publishing (intellectual rights). Everything is digitally manufactured outside the U.S. and the publishing takes place in Canada (Canadian ISBN).

The product is sold to a U.S. printer and distributor for the U.S. market.

Can this be considered foreign source income or is it ECI, as it is sold to a U.S. company?

From what I gather from Publication 519, rent properties/royalties/etc. are subject to tax where they are used. But, as the ISBN is Canadian... I think the place where the intellectual right is used/registered is Canada.

Does anybody have a clue?

Thanks