Despite skepticism from prominent lawyers and Wall Street analysts, bitcoin investors are increasingly confident the Securities and Exchange Commission will approve at least one of the three proposed bitcoin-focused exchange-traded funds currently under consideration.

Pricing in futures contracts traded on BitMEX, a popular exchange that is incorporated in the Republic of Seychelles, as well as the rapidly declining premium for shares of the Grayscale Bitcoin Trust traded on the secondary market suggest that some market participants are bracing for approval, said Spencer Bogart, an analyst at Needham & Co. Bogart is one of the few Wall Street analysts who cover Bitcoin.

The trust’s premium over bitcoin’s net asset value has shrunk from about 42.21% in early January to about 13% in recent trade, according to data provided by Grayscale.

The shrinking premium suggests investors are less willing to pay for shares of the trust because they expect one of the ETFs to be approved in the near future, Bogart said. Shares of a bitcoin ETF would likely trade much closer to the cryptocurrency’s net asset value, bitcoin watchers said.

The trading activity is at odds with the likelihood of approval tabulated by Bogart, who places it at less than 25%. Last month, a former lawyer for Gemini Trading, the bitcoin exchange operated by Tyler and Cameron Winklevoss, said he believed the SEC wouldn't approve the creation of a bitcoin exchange-traded fund. The SEC has said it would issue a ruling on the Winklevoss’s proposed bitcoin ETF, known as the Winklevoss Bitcoin Trust, by March 11.

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BitMEX recently launched a futures contract that allows investors to bet on the odds that the Winklevoss ETF will be approved. It is presently trading around 33.3, indicating that the thinly traded market is pricing in about a 33% chance of approval, which is higher than what Bogart expects. BitMEX couldn't be reached for immediate comment.

A few weeks ago, Grayscale, which launched the Bitcoin Investment Trust in 2013, filed for an initial public offering that would allow its trust to trade as an ETF on the New York Stock Exchange. The Grayscale bitcoin trust is presently one of the few registered investment vehicles available to financial institutions. A company known as SolidX has also filed for a bitcoin ETF.

Bogart believes that if an ETF is approved, more than $300 million of new institutional capital would flood the bitcoin ecosystem during the first week alone. Such an influx would likely cause the price of a single coin to skyrocket. Typically, trading volume in the global bitcoin market measures less than $100 million a day.

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Chris Burniske, blockchain products lead at ARK Invest, believes that the decline in the Grayscale bitcoin trust’s premium may suggest that investors are taking a wait-and-see approach ahead of the SEC’s decision. ARK holds shares in the trust.

The Grayscale trust, which is a taxable registered security, may appeal to institutions as well as individuals who want to add bitcoin to their retirement accounts, Burniske said. The fund was first launched in 2013. Only accredited investors can invest directly in the trust; for others, shares are traded on the secondary market. The trust’s market capitalization was $205.6 million as of last week, according to company data.

Grayscale, which filed for the fund’s IPO on Jan. 20, declined to comment further, citing restrictions imposed by federal securities laws.