Originally Posted by number_6

Any OW airline can re-issue the ticket, while the ticketing airline is required to do the re-issue. So other airlines do it when they want to; they are allowed to refuse and require you to have AY do it. In practice they rarely refuse unless there is something wrong with the ticket. 99% of the time there is no problem. I've had problems with AY ticketing for years, but I wouldn't hesitate to buy through them if there was a price difference.