The SEC is seeking public comment on the Ark 21Shares Bitcoin ETF application, and has pushed back the decision date by several weeks to potentially months. 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. 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.