Bitcoin will make its debut on a major exchange Sunday, a landmark for the cryptocurrency that has generated enthusiasm among some investors and more than a little anxiety from others.

The Cboe Futures Exchange in Chicago will open trading in bitcoin futures at 2300 GMT on Sunday, a move that is expected to be followed a week later by a rival listing on Chicago Mercantile Exchange.

"Bitcoin bonanza takes hold of world markets," proclaimed the front page of the Times of London on Friday, reporting on the latest record price of the digital currency.

Among those cheering the launch are the Winklevoss twins, who have been called the first bitcoin billionaires. Critics include financial commentator Jim Cramer, who warns that prices could tumble once the new trading venues open the door to "short sellers," who bet on downward moves in assets.

The two launches were made possible after a key US regulator, the Commodities and Futures Trading Commission, gave the green light to the exchanges on December 1, while warning "of the potentially high level of volatility and risk in trading these contracts."

Anticipation of the first mainstream listings for the digital currency has been a catalyst for a sharp price increase in recent weeks. Bitcoin opened 2017 at around $1,000, surged past $10,000 for the first time last month and soared as high as $16,777 on Thursday before retreating somewhat.

The actual opening of the Cboe market, an electronic trading venue, is expected to be a low-key affair, lacking the pomp of an initial public offering, which is often marked by the new entrant ringing the bell of the New York Stock Exchange.

"There won't be any ceremony, no champagne," said a person close to the Cboe process.

"It's going to happen quietly, a switch flipping," the person added. "There are not going to be many people in the office."

Going mainstream -

The embrace by mainstream exchanges of bitcoin futures -- a type of derivative contract that allows trading based on bitcoin's movement, without taking ownership of the currency itself -- marks a sea change from the days when the digital currency was associated with drug dealing and other illicit activities.

Still, plenty of key figures in and around markets are taking a cautious approach to bitcoin, which has no central bank backing it, and no legal exchange rate.

The Futures Industry Association, which includes some of the world's biggest derivatives brokerages, criticized the CFTC's move in a letter to the regulator, saying contracts are being rushed through without properly weighing the risks.

"A more thorough and considered process would have allowed for a robust public discussion among clearing member firms, exchanges and clearing houses," the association said.

Several leading financial heavyweights are still studying bitcoin and not serving as financial intermediaries. This group includes JPMorgan Chase, Bank of America Merrill Lynch, Citigroup, Barclays, Morgan Stanley and Societe Generale, said people close to the matter.

Of the larger banks, only Goldman Sachs and ABN Amro are serving as intermediaries for the trades. That means most of the terrain will be dominated by smaller entities that are typically requiring larger than usual margin requirements -- funds set aside as collateral in case of losses.

Wedbush Securities has lifted its margin requirements and is only permitting trades from clients on a "selected" basis, said Bob Fitzsimmons, a managing director for the firm.

"We are commissioning only the select clients who have experience in bitcoins," he said.

"Our risk systems are ready and we have made sure we have our customers and firm protected by increased margins and increased scrutiny."

source: AFP