In the second round since the FCC boosted its asking price increase by 10% per round, bidders in the fourth, and last, stage of the forward portion of the spectrum auction bid up the total by $42 million—to $18,970,686,415 in round 23 from $18,928,450,387 in round 22.
The auction has already met its two key clearing targets and broadcasters already know how much they are getting, about $10 billion, so the auction will end at the end of the current forward auction stage. The difference between that $10 billion payout plus $1.9 billion for auction and TV station post-auction relocation expenses will go to the treasury.
The auction can't close until there is no more bidding in any of the 416 markets, which is not yet the case. For example, in round 22 there was more demand than supply in a number of smaller (below the top 40) markets, including Eugene. Ore., and Erie, Pa.
The FCC is making 70 MHz of spectrum available, divided into seven 10 MHz blocks, in each market thanks to broadcasters giving up 84 MHz of their spectrum (14 of which goes to guard bands and is not up for bid).
The forward auction is a clock auction in which the FCC raises the price in each round until demand does not exceed supply in each round.
At that point the auction will close and a second auction will be held among winning bidders to assign specific frequencies.