22 CFR § 120.19 - Reexport.
(1) An actual shipment or transmission of a defense article from one foreign country to another foreign country, including the sending or taking of a defense article to or from such countries in any manner;
(2) Releasing or otherwise transferring technical data to a foreign person who is a citizen or permanent resident of a country other than the foreign country where the release or transfer takes place (a “deemed reexport”); or
(3) Transferring registration, control, or ownership of any aircraft, vessel, or satellite subject to the ITAR between foreign persons.
(b) Any release outside the United States of technical data to a foreign person is deemed to be a reexport to all countries in which the foreign person has held or holds citizenship or holds permanent residency.