[05/13/2015 @ 7:18 PM] Fare gone. Old post. Clean-up.
This looks like a price war for a limited set of dates between Avianca / American and United.
American Airlines and United are offering round-trip flights from Dallas (DFW) to San Jose, Costa Rica (SJO) starting at $310. Flights last week of May to second week of June.
Read More Cheap Flights: Dallas to San Jose, Costa Rica $310 r/t – American / United