Originally Posted by
stargold
No, it's nothing to do with the codeshare. They just keep some seats for assignment at the airport, like most airlines.
So what rows are block to sell as UA codeshare ? If NH block off 5 rows in the 763 in Y on NRT-HKG for UA (UA can only assign seats in those 5 rows), I am sure it works the same way for ORD-NRT.