US Government Rejects AT&T's Takeover of T-Mobile USA

According to Bloomberg, AT&T decided to acquire one of its competitors, T-Mobile, leaving Sprint and Verizon far behind. however, the US government sued AT&T to block the acquisition, under the main claim that it will substantially lessen competition, and directly customers. 
In its project, AT&T was claiming that the acquisition will be synergistic and will benefit to customers as it would allow save on infrastructure that should translate in cheaper subscription plans. As the US government acted via its Justice Department, a federal judge will have to decide what would be the next step in this story.