I've just completed a search of flights on BA for WAW - LAS at the beginning of March. Interestingly, the only flights which show are the BA metal flights connecting to America West. For some reason, it will not show any of the flights that BA and AA codeshare together.

Is this because they are prohibted for selling transatlantic tickets together, no matter whether the leg is within the US? This doesn't make sense to me, because when I look at AA.com to book the same route, it will show AA codeshare flights LHR - WAW, saying "operated by British Airways".

This is annoying, because I just don't want to fly America West, but I'm not provided with any options.