A portfolio of stocks, bonds, or other securities administered by a team of one or more managers from an investment company who make buy and sell decisions on component securities. Capital is contributed by smaller investors who buy shares in the mutual fund rather than the individual stocks and bonds in its portfolio. The return on the fund's holdings is distributed back to its contributors, or shareholders, minus various fees and commissions. This system allows small investors to participate in the reduced risk of a large and diverse portfolio that they could not otherwise build themselves. They also have the benefit of professional managers overseeing their money who have the time and expertise to analyze and pick securities. There are two types of mutual funds, open and closed-ended. Shares in closed-end funds, are readily transferable in the open market and are bought and sold, like other stock. These funds do not accept new contributions from investors, but only reinvest the return on the existing portfolio. Open-end funds sell their own new shares to investors, stand ready to buy back their old shares, and are not listed on exchanges. Open-end funds are so called because their capitalization is not fixed.