Originally Posted by
smxflyer
Delays of 3-4 hrs are due 300 Euros, so definitely entitled to some compensation.
Only for a flight of less than 3500km. LIS-EWR is 5,447km, so compensation isn't due unless the delay is more than 4 hours.
Realistically, UA isn't going to readily pay a cent of EU261 compensation in a case like this. Non-EU airline, for a US domestic flight, with a passenger arriving late from a different airlines flight. They will almost certainly offer compensation in the form of vouchers due to the extended delay of the connecting flight (which their website is claiming is due to "operational difficulties", not weather).
Having said that, there is a precedence that compensation is potentially due.
European Commission - PRESS RELEASES - Press release - Passengers on connecting flights must be compensated when their flight arrives at the final destination at least three hours late If both flights were on United, then per that ruling compensation would be due - it's the switch of airlines that is going to cause difficulty...
Starting with TAP would certainly be the best option, but I wouldn't expect it to be an easy fight...