Originally Posted by
lincolnjkc
For clarity, I believe you mean either "non-EU carrier departing from a non-EU station" or a "US carrier departing from a non-EU station" -- but either way, yes. EU 261 is only a 100% magic pill if you're on a EU carrier; otherwise it's the 50% magic pill: you can get its benefits leaving the EU but not arriving.
Even on EU carriers, there can be exceptions if the route doesn't touch the EU. For instance, there's a KLM flight between DPS and SIN and an AF flight between EZE and MVD.