Originally Posted by ilovetofly

Neither AA or JAL can assign Y seats with AA codeshare flight. I know that ones can choose seats at JAL website with JAL PNR. EXP desk said that there is no JAL PNR when the JAL flight is booked under AA flight #.

Not sure if J or F would be different though.

Originally Posted by k_getchell

I think you're right - I flew NRT-SIN and back again on JAL last Sept. Booked in N class on the AA codeshare number. No seat assignment for me until I checked in. Tried online and on the phone with both AA and JAL. No dice.

Didn't bother trying again at T-72 though, so might have been able to get something before checking if I had.

For BA though, AA Plat and ExPlat should be able to select seats no matter what the fare basis. I've done this multiple times on both BA and AA flight number on BA metal without any problem.