Cameron (L) and Tyler (R) Winklevoss. Adam Jeffery | CNBC

Would-be bitcoin ETF investors are in wait-and-see mode as the Securities and Exchange Commission reconsiders whether to allow the first bitcoin exchange-traded fund to come to fruition. To the dismay of many, the SEC rejected the Winklevoss Bitcoin ETF (COIN) in a March 10 decision, citing a lack of regulation and surveillance-sharing agreements between exchanges. Bats Global Markets, operator of the exchange on which the ETF would trade and which is owned by the same parent company — CBOE — as ETF.com, responded to the SEC's verdict by filing a "petition for review" of the disapproval on March 24. Bats argued that the commission's initial conclusion "is clearly erroneous," "inconsistent with prior ETP [exchange-traded products] approval orders" and that "the manipulation concerns ... are overstated and largely theoretical." More from ETF.com:

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This Trump ETF trade completely unwinds Bats urged the SEC to approve its proposed rule change, which would open the door to the listing of the ETF and "provide investors access to bitcoin through a regulated and transparent investment vehicle." On April 24 the SEC agreed to consider Bats' petition for review and asked for public comments on the original disapproval order. The last of those comments was submitted on May 15, setting the stage for a new round of deliberations by the commission.

High bar for approval

Though hopes are high that the bitcoin ETF will eventually be approved — public comments on the fund have been largely positive — analysts aren't confident the SEC will turn around so soon after its previous negative ruling and suddenly give it the green light. Spencer Bogart, managing director and head of research for Blockchain Capital, is skeptical that the SEC will change its tune on the bitcoin ETF. "Their reason for disapproval was the underlying markets for bitcoin, which haven't changed in the weeks since they made their decision," he said. "One of the issues was that Bats hadn't set up surveillance-sharing agreements with the major exchanges on which bitcoin is traded, with the purpose of identifying and stomping out market manipulation. Even if they did, a lot of those exchanges reside in jurisdictions that don't have much of a regulatory body that can go and take action against people that are doing something bad to the market."

However, Bogart did leave open the possibility that the SEC's thinking could change on the ETF if a new set of people look into the matter. "It is possible that, in the short time period from when the SEC disapproved to when the petition was granted, there was a significant regime change at the SEC," explained Bogart. "You could have a different group of people who want to review the matter because they aren't sure the decision to disapprove was a good choice. I've heard whisperings that there are many people within this administration who are friendly or at least amicable to digital currencies like bitcoin."

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