Originally Posted by
fransknorge
It does not matter for Avios and Tier Points for a flight operated by AA and whether it is marketed for BA, IB or AA for an international flight.
For domestic there are some nuances.
there are a lot of differences between ba code and aa code for avios for example a OW LHR-JFK in S class on BA earns 1729 avios and on AA earns 863 avios in business and first class the differences are even bigger