Brokerage firm Bernstein on Monday stated that the U.S. Securities and Exchange Commission (SEC) may find it challenging to maintain its current position on spot Bitcoin (CRYPTO: BTC) exchange-traded funds (ETFs), suggesting that the chances of approval are relatively high. The report highlights that the SEC has already given the green light to futures-based Bitcoin ETFs, including those that are leverage-based, on the grounds that futures pricing originates from a regulated exchange such as the CME, Coindesk reported.