Fidelity announced on Tuesday it would allow up to 20% of assets in 401(k)s to be invested in bitcoin, though the 23,000 companies whose employees save for retirement in Fidelity accounts would have the final say on the permissible percentage. Employers are held to a fiduciary standard when offering retirement accounts and are responsible for evaluating plans for any risky investments or high fees. Some companies may choose to only to allow 5% of portfolios to be invested in bitcoin, while others might set a 10% ceiling, Fidelity said.

See: Why I don’t want bitcoin in my 401(k) 

Bitcoin and other cryptocurrencies are becoming more popular, but they’re still volatile investments. Many advisers suggest individuals proceed with caution when investing in these assets, and refrain from doing so with money they that’s needed in either the near term or the long term (such as retirement savings). But because there’s so much “hype” around these assets, people feel they need to invest in them or be “left behind,” Khawar told the Journal. 

The Labor Department had issued a warning in March to employers about allowing cryptocurrency investment via retirement accounts. As a result, the department will likely accept some amount of bitcoin in a 401(k) plan but will apply “pressure for that number to be below 5%,” according to Jaret Seiberg of Cowen Washington Research Group. “If it wanted the exposure to be zero, we believe the agency would have gone further than just speaking to a newspaper.” 

Though the investing world is still watching how cryptocurrencies will fit into employer-sponsored retirement plans, investors can include bitcoin and other digital assets in IRAs already.