US regulator the Federal Communications Commission said it had begun its procedures related to the planned merger of AT&T and T-Mobile USA, which would create the biggest mobile operator in the country by some margin. Apparently, the operators are expected to file documentation with the regulator by the end of the month, and by opening a “docket” for the case, the FCC is now ready to begin its work. eWeek said that the watchdog will investigate if the deal serves “the public interest, convenience and necessity,” and the “burden of proof” is on AT&T/T-Mobile to show the benefits. According to Bloomberg, the transaction will be subject to a “coordinated review” involving the FCC and the Justice Department, with the two agencies working on “parallel tracks” during the process. No timeframe has been given for a completion of the probe, although the work will be conducted as swiftly as possible. The FCC’s documentation also includes a “protective order,” to ensure that commercial information disclosed during the procedure remains confidential.

AT&T announced its plan to acquire T-Mobile USA last month, in a deal which has been widely reported as an attempt by AT&T to ensure it has the necessary spectrum allocations to meet growing mobile service demand. The companies have already said that they expect the deal to take 12 months to complete, underlining the complicated nature of the transaction. Sprint Nextel, the US number three operator which will lag significantly behind AT&T/T-Mobile and Verizon Wireless when the transaction is completed, has already stated that it opposes the deal, arguing that the combination “would reverse nearly three decades of actions by the US government and the courts that modernised and opened US communications markets to competition.”