The FCC plans to add 128.5MHz. of spectrum to its screening procedures for vetting mergers and spectrum sales. Sprint (S -4.1%) owns 101MHz. of the spectrum, via its acquisition of Clearwire and its valuable 2.5GHz. band spectrum (good for urban areas).
The rule change, due for a May 15 vote, relates to the FCC's scrutiny of deals that give a carrier more than 1/3 of all spectrum in a particular market. Sprint will exceed that threshold in most big markets once the change goes through.
Though Sprint won't be forced to sell spectrum in those markets, it could have a much harder time adding to its spectrum position within them via M&A - say, through a merger with T-Mobile USA (TMUS -3.6%).
Separately, the FCC plans to provide tougher scrutiny of deals that would lead to a single carrier having over 1/3 of all quality low-frequency (sub-1GHz., better for buildings and rural areas) spectrum in a market, and to limit how much a carrier with such a spectrum position can bid in 2015's anticipated low-frequency auctions.
AT&T (T +1.3%) and Verizon (VZ +1.5%), which together control a giant share of low-frequency U.S. mobile spectrum, are the companies targeted by those proposals. Sprint, T-Mobile, and other rivals have been pressuring the FCC to limit how much spectrum AT&T and Verizon can buy in the 2015 auction.