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Bitcoin futures fall on second day of trading; Bitcoin exchange faces cyberattack

Evelyn Cheng
Dan Kitwood | Getty Images. The price of bitcoin fell below $8,000 for the third time in four days on Monday.

Bitcoin futures (CBOE Futures Exchange: @XBT.1) fell in low volume Tuesday in their second day of trading on the Cboe Futures Exchange. Trading volume in the most popular contract, which expires in January, was less than half what it was the prior day at 729 as of 12:08 p.m., ET. Volume had already topped 800 about two hours after the futures launch Sunday night and was near 3,000 by 9:30 a.m. Monday morning. The Cboe bitcoin futures, listed under the ticker XBT, traded 1 percent lower near $18,330 after earlier falling more than 3.5 percent. The contract had soared nearly 20 percent in its Monday debut, with a total 4,127 contracts traded and about 20 firms participating, according to Cboe. However, some of the largest banks, such as Goldman Sachs, offered limited to no support for the Cboe bitcoin futures as of Monday. Cboe did not immediately respond to a CNBC request for comment on Tuesday's low trading volume.

Bitcoin (Exchange: BTC=) itself traded more than 2.5 percent higher midday Tuesday to $17,142, according to CoinDesk's bitcoin price index, which tracks prices from digital currency exchanges Bitstamp, Coinbase, itBit and Bitfinex. The digital currency has surged about 1,700 percent this year as investor interest has grown despite criticism that bitcoin is in a bubble. Two of the largest exchanges for U.S. dollar-bitcoin trading reported technical issues Tuesday. Coinbase, one of the leading platforms in the U.S. for buying and selling bitcoin, reported a "partial system outage" on its support website as of 11:51 a.m., ET. The company also said in a 10:39 a.m. status update that buys and sells for ethereum and litecoin "are temporarily disabled." Litecoin briefly surged more than 80 percent over the last 24 hours to a record high of $341.72, while ethereum surged more than 30 percent over that time to an all-time high above $635, according to CoinMarketCap. Coinbase's GDAX exchange website also said there is a "minor service outage." The company did not immediately respond to a CNBC request for comment. Bitfinex tweeted Tuesday morning that it is once again under a DDoS, or distributed denial-of-service attack, which attempts to paralyze a system with a flood of information. The exchange had tweeted Thursday it was "under significant denial-of-service attack for the past several days" and that "the attack has recently worsened." Bitfinex also tweeted last Monday that its platform was briefly affected by an intentional DDoS attack. Bitfinex had the largest share of U.S. dollar-bitcoin trading volume late Tuesday morning at 33 percent, while Coinbase had about 22 percent, according to CryptoCompare. Bitfinex did not immediately respond to a CNBC request for comment. Tweet Cboe's bitcoin futures launch comes a week ahead of CME's own product in a race by major exchanges to launch bitcoin derivatives. Cantor Fitzgerald and Nasdaq are also planning their own derivatives products. Cryptocurrency enthusiasts say the launch of bitcoin derivatives will allow institutional investors to buy into the digital currency trend, helping establish bitcoin as a legitimate asset class and pave the way for an exchange-traded fund. VanEck refiled for a bitcoin ETF on Monday.

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