MIAMI - With the average equity mutual fund portfolio down more than 38% in 2008, money market mutual funds are quickly becoming one of the only safe havens for risk-averse investors. Money market fund assets recently topped $4 trillion for the first time, making money funds the single largest mutual fund group, according to the Investment Company Institute.

However, while the industry certainly has reason to celebrate all that cash piling up, some mutual fund leaders warn that hoarding cash in ultra-safe investments creates its own set of risks. Others note that regulators are bound to change money funds' mandate, and that due to zero yields, many money fund companies are absorbing administration fees to prop up NAVs.

Subscribe Now

Access to premium content including in-depth coverage of mutual funds, hedge funds, 401(K)s, 529 plans, and more.

3-Week Free Trial

Insight and analysis into the management, marketing, operations and technology of the asset management industry.