The U.S. Securities and Exchange Commission (SEC) has kicked off its review of WisdomTree's bitcoin ETF application, starting the countdown clock to a final decision.

The SEC published a public notice Friday announcing it would begin evaluating the WisdomTree Bitcoin Trust, which the ETF giant filed with Cboe BZX Exchange. WisdomTree first filed for this ETF last month, but has previously attempted to launch a regulated financial product with exposure to cryptocurrencies.

A bitcoin ETF would provide retail and institutional investors a chance to invest in a regulated financial product incorporating the world's oldest cryptocurrency, without requiring them to invest in the crypto directly. This is seen as a potentially safer way to gain exposure to the still-young crypto sector, which can be volatile or frothy at times.

This is the second active bitcoin exchange-traded fund (ETF) application the federal regulator is evaluating in the U.S. The first, filed by VanEck, has been under review for a few weeks, with its initial comment period closing on Friday. As of press time, only five comments had been filed.

The regulator's initial decision on whether to approve or reject, or otherwise continue evaluating VanEck's application is expected to come next month.

Also on Friday, Kryptoin Investment Advisors, an asset manager launched by Jason Toussaint of SPDR Gold Shares fame, filed a registration form for a bitcoin ETF, bringing the total number of active applications to eight.

The others include the Fidelity-linked Wise Origin Bitcoin Trust, NYDIG, Valkyrie, Anthony Scaramucci's SkyBridge Capital and Simplify.

The SEC has blocked all attempts at launching a bitcoin ETF to date, rejecting over a dozen applications in past years. Despite that, many expect an ETF to be approved for the first time in the U.S. in 2021.

Several bitcoin ETFs have already launched in Canada and one in Brazil, with other crypto exchange-traded products being traded in other nations as well.