Several regulatory and legal experts said they expected the Mt.Gox shutdown could spur regulators to take more immediate steps to protect future customers.
Jeffrey Matsuura, a lawyer at Alliance Law Group in Virginia who specializes in online commerce issues, said he wouldn't be surprised if state or federal consumer protection agencies eventually take some kind of action regarding Mt. Gox and other exchanges.
But Jerry Brito, a senior research fellow at the Mercatus Center at George Mason University, said people who deposited bitcoins with Mt.Gox knew that the exchange had experienced problems in recent months.
"At this point, bitcoin is speculative," he said. "People are going in with eyes wide open."
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Thus far, the only U.S. regulatory agency with specific oversight of Mt.Gox is the U.S. Treasury Department's anti-money laundering unit, the Financial Crimes Enforcement Network, or FinCEN, after the exchange agreed to register as a money services business last summer.
New York State's top banking regulator is exploring licensing requirements for bitcoin exchanges, while the Commodity Futures Trading Commission has considered whether to set rules for the virtual currency. And federal prosecutors in New York have issued subpoenas to Mt.Gox and other exchanges seeking information on how they had handled recent cyber attacks, a source told Reuters.
"Bitcoin in many ways is terra incognita for the regulatory system," said Joseph Grundfest, a law professor at Stanford University and a former SEC commissioner.
But, he added, that would not stop federal prosecutors in Manhattan from investigating criminal activity involving bitcoins if any of the transactions had a connection to New York.
"The lack of clarity about formal regulatory status provides no safe harbor for liability for criminal fraud," he said.