When Bitwise filed its registration statement with the SEC for a Bitcoin ETF in January, it said the filing responded to questions that the agency had raised about previous bitcoin ETF filings, but the SEC apparently did not agree.

After receiving a filing from the NYSE Arca about a proposed rule change to list and trade shares of the Bitwise Bitcoin ETF, the agency delayed a decision on the Bitwise ETF in late March, along with a decision on the VanEck SolidX Bitcoin Shares. It said it needed more time and by May 16 it expected to “approve or disapprove or institute proceedings” to help make its decision.

The SEC has apparently decided on the latter after receiving an amendment to the NYSE Arca proposed rule change earlier this month and a report from Bitwise that 95% of current spot Bitcoin trading is fake, once again delaying a decision on the Bitwise Bitcoin ETF. The proposed Bitwise Bitcoin ETF Trust would track an index that draws prices from only those cryptocurrency exchanges that Bitwise says do the “majority of currently verifiable Bitcoin trading.”

The agency, which has already received 25 comments on the proposal — most of them negative — is again seeking public comment, this time on 14 questions, many asking about potential manipulation of the Bitcoin market.

Among the questions in its notice: whether commentators agree with assertions made by the NYSE Arca and Bitwise that the Bitwise Bitcoin ETF is uniquely resistant to manipulation, that the 10 Bitcoin trading venues exchanges it would reference represent “substantially all of the economically significant Bitcoin trading volume in the world” and that “a significant, regulated and surveilled market for Bitcoin futures exists” to prevent manipulation.

Comments will be due 21 days after the notice is published in the Federal Register, and rebuttal comments are due 35 days after publication.

SEC Chairman Jay Clayton, who has been reticent about cryptocurrencies, told Fox Business News in late March that he’s concerned whether “it can be reasonably demonstrated that the underlying trading [in Bitcoin] is generally not manipulated, it’s happening on reliable venues with good rules and that custody is something we can feel comfortable about.”

Meanwhile Bitcoin, which began trading this year at under $4,000, has jumped over $7,000 in recent trading. In late December 2017, it came within $200 of $20,000.

— Check out Fidelity Said to Offer Bitcoin Trading Within Weeks on ThinkAdvisor.