Three financial watchdogs in the United States have issued a warning to investors considering certain individual retirement accounts with exposure to cryptocurrencies.

“Some self-directed IRAs may offer investments in ‘crypto assets’ such as ‘virtual currencies,’ ‘coins,’ and ‘tokens’,” said the notice. “Many of the trading platforms for these crypto assets refer to themselves as ‘exchanges,’ which may give investors the misimpression that they have registered with the SEC.”