Definition: By law, every year, mutual funds must distribute that year’s net investment income (the total of dividends and interest received, less fund expenses) and net realized gain (gains less losses on securities sales) to its shareholders. These distributions are taxable income reported to the IRS on Form 1099. Investors must report the income on their tax returns. This poses a problem for some mutual fund investors who make initial purchases of mutual funds near the end of a calendar year. Because they receive a capital gains distribution, they immediately receive taxable income and face a mutual fund NAV that is reduced from the distribution.