This represents a contract for a "reverse" VCG (vickery-clark-groves) auction also known as a "second price auction". This means that a number of bidders will bid, and the lowest bidder will win the auction. The winner will pay the second lowest bid.
The contract runs one auction at a time.
Each auction is instantiated with a fixed number of bidders. Once the target number of bidders has been satisfied, the auction may be closed and a winner selected.
Authorizing bidders based on predetermined addresses will be a necessary but later feature of this contract.