Direxion, ProShares and VanEck are among a handful of ETF issuers that have withdrawn filings to launch bitcoin ETFs at the request of U.S. regulators. The Securities and Exchange Commission (SEC) requested the issuers withdraw their filings.

The news of the withdrawn plans for cryptocurrency ETFs comes just days after the SEC said it is soliciting comments from the investing public on two proposed rules changes that could prompt the long-awaited introductions of bitcoin ETFs.

The SEC is seeking input on proposed rules changes by the Chicago Board Options Exchange (Cboe) that could allow the exchange to list up to four bitcoin ETFs. Cboe was the first exchange operator in the U.S. to introduce futures based on the volatile digital currency, having done so last month.

Direxion Shares ETF TrustExchange Listed Funds Trust and ProShares Trust all filed to create exchange-traded products in the past month. Yet notably, none of the proposed offerings would have held bitcoin directly – rather, their price movements would have been driven by changes in the still-nascent market for bitcoin futures,” reports Coindesk.com.

First Trust and VanEck are also among the issuers that withdrew plans for bitcoin ETFs.

Thus far, no exchange traded products related to digital currencies have been approved by U.S. regulators. Derivatives help increase liquidity and improve markets for an asset category by allowing investors to bet on ups and downs of an asset, evening allowing individuals to adopt market-neutral strategies. They are also a key component in the creation of many futures-backed ETFs utilized by a range of investors.

“While the SEC has released the Cboe proposals for public comment, it has a longer history of pressing for bitcoin ETF proposal withdrawals,” according to Coindesk. “Several organizations killed their ETF efforts last year at the request of the agency – at the same time, at least two of these proposals were denied because bitcoin futures contracts did not exist at the time.”

For more information on the cryptocurrency market, visit our Bitcoin category.