It is guided by two Wall Street trade groups that they are interested in opening ETFs and mutual funds based on bitcoins. They have not been able to comply with the SEC rules so far, this letter creates the case that these companies are offering cryptocurrency-based investment products. These American securities and its exchange commission issued an employee letter on January 18.
Source - https://cointelegraph.com/news/sec-says-crypto-based-funds-not-ready-for-regulation