Ericsson returned to profit in its fourth quarter of 2019 despite a drop in sales in its biggest market, North America, which it blamed on uncertainties surrounding the proposed merger of Sprint and T-Mobile, and the impact of that outcome on 5G. The US market is waiting to see whether the third and fourth MNOs will be allowed to merge, a move that has been approved by regulators but could be blocked by legal action from several states on the grounds of reduced competition. The operators argue that, if they can combine their operations, they will have the scale to build out 5G more quickly and comprehensively, by combining Sprint’s midband 2.5 GHz spectrum with T-Mobile’s 600 MHz coverage band.…