The FCC is asking AT&T and T-Mobile USA some pointed questions about the companies’ proposed merger.

On Friday, the FCC sent AT&T a 78-page document asking the company to back up many of its reasons for acquiring T-Mobile, such as its need for additional spectrum.

The agency requested additional information about several of the statements laid out in AT&T’s public interest statement on the merger, including its capacity problems and pledge to expand LTE to an additional 55 million Americans should the merger be approved.

The FCC also asked questions about pricing, competition and whether Verizon Wireless and AT&T cut each other deals on collocation and backhaul rates.

AT&T called the FCC’s information request, which contained 50 detailed questions and several forms, “standard procedure.”

“It is standard procedure for the FCC to submit data requests to parties to a license transfer,” said AT&T spokeswoman Margaret Boles. “We will provide the FCC with all the data it needs to evaluate this transaction, and we are confident that, after doing so, the FCC will recognize its significant public interest benefits and approve the transaction.”

T-Mobile parent company Deutsche Telekom received a similar, 74-page information request from the FCC. The agency asked Deutsche Telekom questions about its spectrum holdings, backhaul and pricing, and requested information about how T-Mobile would perform if it became a stand-alone business without support from its parent company.

AT&T and Deutsche Telekom have until June 10 to provide responses to the FCC’s latest round of questions.

Today, May 31, marks the first deadline in the FCC’s public comment period on AT&T’s buyout of T-Mobile. People interested in opposing the deal have until the end of the day to file their petitions to deny with the agency.