Dish Network, Cellular South, the Rural Cellular Association (RCA) and a group of open Internet advocates are asking the FCC to block AT&T's $1.9 billion purchase of Qualcomm's Flo TV spectrum.

The groups argue that the deal for 11 valuable licenses in the lower 700 MHz block, once used for Qualcomm's now-defunct mobile television service, would further stymie competition in the wireless industry.

"The Commission should deny the Applications because entrusting additional beachfront spectrum to AT&T would cause irreparable harm to competition and consumers," the RCA said in its FCC filing. "In a market that is teetering dangerously on the brink of true duopoly, the Commission should not tip the balance further."

AT&T and Verizon Wireless have both purchased considerable swaths of the 700 MHz spectrum to use for their respective LTE networks. If the FCC approves AT&T's acquisition of Qualcomm's 700 MHz licenses, AT&T will gain access to additional beachfront spectrum in New York, Boston, Philadelphia, Los Angeles and San Francisco.

Dish Network asked the FCC to either block the deal or require AT&T to divest those markets as part of its conditions to approve the deal.

In all, the 700 MHz D block and E block licenses on sale cover more than 300 million people nationwide and would give AT&T between 6 MHz and 80 MHz of spectrum below 1 GHz in the relevant markets. AT&T plans to use the unpaired spectrum for extra downlink capacity in its LTE network, which is slated to begin commercial operations some time this year.

Cellular South wants the FCC to block the deal, or failing that, mandate AT&T enter into data roaming agreements; prevent AT&T from forming device exclusivity deals; and stop the carrier from what Cellular South called "anticompetitive 700 MHz equipment design and procurement practices."

In a joint petition, Free Press, Public Knowledge, Media Access Project, Consumers Union and the New America Foundation argued that AT&T's application for the 700 MHz holdings "ignores facts that clearly demonstrate that this transaction will limit competition and harm consumers."

The groups want the FCC to mandate interoperability in band classes in 700 MHz spectrum; stop AT&T from forming exclusive new device deals; cut back on early termination fees; offer reasonably priced backhaul to competitors; and phase out AT&T's receipt of money from the Universal Service Fund.

The petitions opposing AT&T's purchase of additional 700 MHz spectrum reflect ongoing disputes between small and large operators over data roaming, interoperability in the 700 MHz band and device exclusivity agreements. The FCC has made few recent moves to address the contentious issues and it is not clear whether the petitions will be enough to cause it to block the deal.

AT&T could not be reached for comment by press time. The carrier has until March 21 to file a response to the petitions with the FCC.