Single bidder wins Silk Road Bitcoin booty

A single unnamed bidder has snapped up bitcoins valued at nearly US$17.7 million (A$18.8 million) seized by the US Marshalls Service following an online auction last week.

The 29,655 bitcoins, which were discovered on Silk Road servers, were auctioned over a 12-hour period late last week in nine blocks of 3000 bitcoins, and one block of 2657 bitcoins.

The auction drew 63 bids from 45 registered bidders.

The price of Bitcoin rose last week, adding to the winners gains - it was last priced at US$652.02 (A$687.24), up 2 percent on the session. It has gained more than 15 percent since June 25, according to digital currency exchange Coindesk.

Several prominent participants revealed they had attempted to purchase some of the bounty, but had been unsuccessful.

Barry Silbert of SecondMarket Holdings, which runs a bitcoin investment platform, said his firm was outbid, as did hedge fund Pantera Capital, which bid below the market price, according to Pantera chief executive Dan Morehead.

Bitcoin Shop, which trades on the over-the-counter market OTCQB, said its bid had also been rejected. The virtual currency ecommerce company bid directly in the auction as well as through a syndicate organised by SecondMarket.

The US Marshals continue to hold about 144,342 additional bitcoins that were subject to a civil forfeiture proceeding.

Silk Road was shut down after an FBI raid in September 2013. Agents took control of its server and arrested the alleged owner and operator of the website, Ross Ulbricht.

Ulbricht is scheduled to face trial in November. He has pleaded not guilty to the four counts against him, including money laundering conspiracy and engaging in a continuing criminal enterprise.

Authorities have separately charged two Australians in connection with their alleged roles in assisting Ulbricht in operating Silk Road.