Originally Posted by
emcampbe
Not sure what it was exactly, but vaguely recall something about the first overwater segment carrier (codeshare or operating carrier) was the one that needs to be used for ticketing.
Experience tells me this isn't true; last year I flew LAN-ORD-ICN-BKK on UA-OZ-OZ (coded as UA-OZ-OZ) and on a 016 ticket through United.com. You can also search for an award ticket on united.com and they often then give you a cash purchase option even when no flights are operated by UA.