ATT and T-Mobile are both eyeing valuable spectrum that Verizon Wireless holds but isnt currently putting to use, according to a report from The Wall Street Journal. The spectrum in question comes from the 700MHz A-block. Verizon paid $2.4 billion for the licenses to those airwaves, which offer better building penetration than higher frequencies, but the largest US carrier hasnt yet put the spectrum to use. The A spectrum is out there, and if someone walks up to me with an offer, we will entertain it, Verizon CFO Fran Shammo has said.