I recently returned from a trip to Singapore and had a frustrating experience getting seats assigned on an AA Codeshare on Japan Airlines on the Tokyo to Singapore leg. I was wondering if anyone else had similar experiences and whether there was anything we could have done differently. I was traveling with my wife, who had Gold Status at the time (this trip put both of us to Platinum, me on a Challenge and her the old fashioned way). We purchased a discounted coach ticket, "N" fare. Travelling AA metal from DFW to Tokyo and then Japan on a AA Codeshare from Tokyo to Singapore the next morning. Similar routing on the way back with Japan Codeshare SIN to HND and AA from NRT to DFW. I called AA and Japan at the time of booking and was told they wouldn't be able to assign seats until 72 hours out, and that I should call back then. At 72 hours out, I called Japan Airlines and was told that I actually wasn't able to get seat assignments until 24 hours out. At 24 hours out, I called them and was told that I actually wouldn't be able to get a seat assignment over the phone and would have to receive it when I checked in for my 1st flight out of DFW. When I checked in at the airport I was told that AA was unable to give me a seat assignment, and I'd need to check in with Japan. I called Japan Airlines from the Admiral's Club and they told me that American Airlines should be able to give me a seat if I was at the airport. I asked the agent in the lounge if she could help and she tried with a supervisor, but said it wasn't open to them. I then called American, who told me the best bet was to ask an agent in the Admiral's Club. When I told her I already had, they said I'd just need to talk to Japan Airlines when I landed in Tokyo. I went to the counter in Tokyo and was told they couldn't give me a seat assignment there, but that I could do it on-line and pointed me to a wifi access point in Starbucks. Of course it said I wasn't able to check in on-line, and when I brought my ipad back to them and showed them, they said I'd just need to come back the next morning before my flight to get a seat. When I pressed it further, they finally said they'd block us two seats for the flight. We were then able to check in the next morning with the seats they had blocked for us. Is this typical of flying on a codeshare? I wouldn't mind nearly as much if I was flying alone, but it was quite exhausting. Flying back wasn't an issue, since we just had the seats assigned at check in at the Singapore airport, and already had our AA seats for the other leg.