A change to the mechanics of BlackRock’s proposed spot bitcoin (BTC) ETF opens the door for Wall Street banks, which face restrictions holding cryptocurrencies, to play a key role. BlackRock recently made it so authorized participants (APs) – a vital part of the ETF ecosystem – will be able to create new fund shares with cash, rather than only with cryptocurrency. As highly regulated U.S. banks are unable to hold bitcoin themselves, this set-up would enable the likes of JPMorgan or Goldman Sachs – firms with some of the largest balance sheets in the world – to act as APs to BlackRock’s ETF. (Whether they want to is another matter.) The cash APs use in this process can then be exchanged into bitcoin by an intermediary and warehoused by the ETF’s custody provider, as per a memo filing relating to a Nov. 28 meeting involving the Securities and Exchange Commission, BlackRock and Nasdaq.