A student points to a monitor displaying BitCoin price against the U.S. dollar via a portal for trading virtual currencies, inside the cryptocurrency mining farm and school at the Ministry of Youth and Sports facility in Caracas, Venezuela, on Thursday, Feb. 22, 2018. Venezuelan President Nicolas Maduro said intended purchases of the country’s cryptocurrency, known as the Petro, surpassed $1 billion in two days of sales. (Bloomberg)

It’s one of the most hotly debated questions in the world of virtual currencies: Is Tether telling the truth when it says that each of its digital coins is backed by one U.S. dollar? The answer could have big ramifications, given that Tether’s coin (also called Tether or USDT) is among the most actively traded cryptocurrencies -- treated by many as a substitute for the greenback on crypto markets around the world.

Over the past few days, USDT has broken out of its historically tight trading range around $1, fueling fresh speculation that investors may be losing faith in the coin. On Oct. 15, USDT traded at about 90 cents on San Francisco-based crypto exchange Kraken.

1. What is Tether?

It’s an issuer of a cryptocurrency with a twist. Unlike Bitcoin, whose value fluctuates wildly from day to day, Tether’s tokens are designed for stability. Prices for the coins have historically stayed near $1 because Tether says each one is backed by a dollar in its bank accounts.

2. Why are the coins popular?

Many traders use them as a substitute for dollars. Tether’s coins are more easily transferable between cryptocurrency exchanges and other online platforms because they don’t have to travel through the banking system. Stable prices have made the coins handy instruments for betting on the direction of other cryptocurrencies.

3. Why are there skeptics?

While Tether has repeatedly said that its coins are fully backed by dollars, the company has yet to provide conclusive evidence of its holdings to the public. There are also questions about Tether’s relationship with Bitfinex, one of the world’s biggest cryptocurrency exchanges. Some market watchers have alleged that trading in Tether’s coins on Bitfinex, which has the same CEO as Tether, has helped prop up Bitcoin’s price.

In a Medium post on Oct. 8, Bitfinex dismissed allegations that it was insolvent and said that withdrawals were functioning as normal. It added that “Complications continue to exist for us in the domain of fiat transactions, as they do for most cryptocurrency-related organisations. However, we continue to do our utmost to minimise any waiting times associated with fiat deposits and withdrawals.”

4. What are U.S. regulators doing?

The U.S. Commodity Futures Trading Commission sent subpoenas to Bitfinex and Tether in December, Bloomberg reported, citing a person familiar with the matter. “We routinely receive legal process from law enforcement agents and regulators conducting investigations,” Bitfinex and Tether said in an emailed statement in January. “It is our policy not to comment on any such requests.”

5. Why is Tether so important for cryptocurrency investors?

Despite their modest total market value of about $2.4 billion, Tether’s coins play an outsized role on cryptocurrency exchanges. They were the second-most traded among all digital currencies after Bitcoin as of Oct. 15, according to data compiled by CoinMarketCap.com. While there are many other so-called stablecoins, none have come close to challenging USDT’s popularity.

6. What’s next?

If authorities were to find any evidence of wrongdoing at Tether or if traders lose faith in the company’s ability to redeem its coins for $1, USDT could quickly lose value. But only time will tell if the coin’s recent slide is just a blip or the start of something bigger. “Tether’s stablecoin dominance will only persist if they can settle community criticisms about their lack of transparency once and for all,” said Jehan Chu, managing partner at blockchain investment and advisory company Kenetic Capital.

(Updates prices from second paragraph.)

--With assistance from Justina Lee and Eric Lam.

To contact the reporters on this story: Andrea Tan in Singapore at atan17@bloomberg.net;Benjamin Robertson in Hong Kong at brobertson29@bloomberg.net;Matthew Leising in Los Angeles at mleising@bloomberg.net

To contact the editors responsible for this story: Sam Mamudi at smamudi@bloomberg.net, Michael Patterson, Eric Lam

©2018 Bloomberg L.P.