Note that this is no longer the case, as the ECJ has (the Airhelp/Austrian Airlines case) ruled that non-EU to non-EU via the EU on an EU carrier (in the particular case, it was Moldova to Thailand via VIE on OS) is not covered by 261 delay compensation (duty of care likely still applies, just not the 600 euro on top).

https://www.lexology.com/library/det...b-93449f1d391f


Therefore, Article 3(1) of Regulation no. 261/2004 cannot be interpreted as meaning that a passenger on a connecting flight, whose initial place of departure and final destination are located in third countries, may avail himself of the provisions of that regulation only because one or more stops of that flight’s segments are located in the territory of the Union.