Millimeter wave spectrum will deliver the fastest version of 5G services, and after six months of semi-secretive auctions, the Federal Communications Commission has finally announced the winners of 28GHz and 24GHz U.S. spectrum. The commission raised over $2.7 billion across the auctions, and the winners were mostly major players in the telecom industry: AT&T bid over $982 million for 831 24GHz licenses, T-Mobile bid $803 million for 1,346 24GHz licenses, and Verizon bid $505 million for 1,066 28GHz licenses.

Almost 60 bidders preregistered for the 24GHz auction, including cable companies Cox and Frontier, as well as a variety of smaller regional carriers. Verizon and AT&T notably used the auctions to augment their prior millimeter wave holdings purchased from other companies, enabling them to expand upon the early 5G services tested and launched on those frequencies. T-Mobile won enough 24GHz licenses to establish itself with millimeter wave towers, after having previously focused almost exclusively on a strategy of using low-frequency and midband holdings for 5G.

Recognizing the spectrum’s potential, the FCC offered significant discounts for small and rural bidders to encourage competition. But the most notable winning bidder after the big three carriers was U.S. Cellular, which won 590 licenses for $254 million.

Though the FCC announced a $702 million haul for 28GHz spectrum in late January, and proceeds of just under $2 billion from its first phase of 24GHz bidding, a second and final “assignment phase” pushed the latter to $2.024 billion as of its close late on May 28. The commission’s bidding process dragged each auction out for over two months, and with gaps between auctions bidders’ identities have remained secret since last November.

Auction participants fought for geography-specific rights to millimeter wave spectrum, such that one carrier could buy rights to 24GHz spectrum in central Utah and another might have already won 28GHz spectrum in the same area. While the two aren’t identical, they’re very similar, and either will enable a carrier to deliver multi-gigabit data rates with extremely low latencies — assuming the carrier is willing to install many “small cell” radios within an area to distribute the high-speed but short-distance millimeter wave signals.

Millimeter wave spectrum was considered all but useless for consumer devices several years ago, as the hardware necessary to send and receive millimeter wave signals tended to be satellite dish- or oven-sized. But engineers saw potential in the spectrum and successfully shrunk millimeter wave hardware into pocketable components, the first of which are now available in Netgear’s Nighthawk 5G Hotspot, Motorola’s 5G Moto Mod, and Samsung’s Galaxy S10 5G phone.

In the absence of millimeter wave holdings or hardware, some carriers have opted to launch 5G on non-millimeter wave “sub-6GHz” frequencies that are likely to be slower, but with the ability to travel longer distances. U.S. carriers plan to use both types of frequencies but to start with millimeter wave, while other carriers will generally start with sub-6GHz frequencies and then add millimeter wave when it becomes locally available.