Bitcoin auctions are carried out by US Marshal Service and consist of 3 steps:
1. Bidder registration
2. Online Auction Period
3. Award and sale close
To participate in an auction, you must submit a registration form that could be found on the website, a copy of government-issued ID, a deposit with at least 200 000 dollars originating from a US bank and a copy of the EFT transmittal receipt. Non-US citizens are also allowed to participate in an auction.
Once you are accepted to participate, you are eligible to make your bid. Here are rules of winners’ determination:
1. The eligible bidder who offers the highest price will be the prevailing bidder;
2. If there are multiple bids at the highest price, the first bid received will prevail; and
3. If a winning bidder defaults, the next highest bidder will be declared the winning bidder.
For details, check https://www.usmarshals.gov/assets/2018/bitcoinauction/