While optimism for SEC approval of a spot bitcoin ETF is running high at the moment, continued investor caution could be warranted. “I had a really good laugh when we saw the BlackRock [spot bitcoin ETF] filing come out,” said Opimas CEO and founder Octavio Marenzi, appearing on CoinDesk TV Monday morning. He took note that the BlackRock fund seeks to use Coinbase (COIN) as its crypto custodian even as that exchange is facing a lawsuit from the SEC.