AT&T has handled the iPhone since its first launch in 2007 when AT&T was chosen as the launch carrier in the US. AT&T has stated that the iPhone 5 was their biggest launch so far in terms of units sold on opening day. The iPhone 5 was actually sold out on Apple's website for launch day shipments. AT&T was quoted saying:
AT&T set a sales record with iPhone 5 over the weekend, making it the fastest-selling iPhone the company has ever offered. Customers ordered more iPhones from AT&T than any previous model, both on its first day of preorders and over the weekend.