It may not be an official code share where United sells tickets on Singapore's planes under its own name, but as a Star Alliance member, I don't care. I get credit on either flight. Although at my level in Mileage Plus, I wouldn't get double miles on Singapore, only United. Star Alliance partners make efforts to fly to each other's hubs for the convenience of passengers needing to transfer to other flights. SAS now flies to Dulles, for example as does Austrian. Lufthansa flies into Denver, etc. I love the seamless travel of Star Alliance and appreciate the efforts of its members to coordinate with each other's flights and hubs.
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