This typically happens a minimum of once a year. Fund of Funds FOF Definition Also known as a multi-manager investment, a fund of funds FOF is a pooled fund that invests in other funds, usually hedge funds or mutual funds. The good news is that, with a little knowledge, you can go from confused to confident when it comes to mutual funds. By Joshua Kennon. The Securities and Exchange Commission SEC requires a fund company to disclose shareholder fees and operating expenses in its fund prospectus.