The U.S. Securities and Exchange Commission (SEC) has delayed a decision on whether to approve Cathie Wood-led Ark Investment Management's (ARK) spot bitcoin exchange-traded fund (ETF), a filing by the regulator showed.

The SEC's Friday filing said it is seeking public comment on the Ark 21Shares Bitcoin ETF application, and has pushed back the decision date by several weeks to potentially months. It was previously due to make a decision by Aug. 13.

The regulator has in recent years rejected dozens of applications for spot bitcoin ETFs, publicly traded investment vehicles that directly track bitcoin price, citing inadequate level of trading surveillance that could leave the underlying spot market subject to fraud and manipulation.

Still, futures-based bitcoin ETFs that track the price of bitcoin futures contracts have been allowed by regulators since October 2021.

Interest from major financial institutions has helped revive the crypto markets in recent months that had been in the doldrums after a series of high-profile firms collapsed last year including Sam Bankman-Fried's FTX.

In June, BlackRock, the world's biggest asset manager, also filed for a bitcoin ETF, a move that many viewed as a gamechanger for the industry.

In 2021, Wood's ARK and crypto investment firm 21Shares US LLC had first teamed up to file an application for a spot bitcoin ETF with the regulator.