Almost certainly you don't own "stock" in a corporation, you own shares of a mutual fund. Mutual funds typically distribute the income of the fund to their shareholders, reportable on Form 1099-DIV. The typical distributions comprise dividends, short term capital gains and long term capital gains. The dividends arise from stock the fund owns that paid dividends to the fund and the short and long term capital gains arise from the fund's own trading activity.
So while it's generally true that you can create capital gains from your own trading activities, it's also true that you can have reportable capital gains distributed to you by mutual funds.
Tom Young
