Is the Sky the Limit?

— L.M., online

A Yes. Companies don’t have unlimited shares. They issue a certain number when they go public via an “initial public offering” (IPO), and they may issue more later, via secondary offerings. You could buy all the shares on the market, but by doing so, your sudden demand for the shares would drive up the price. (That’s why Warren Buffett doesn’t like to publicize what he’s buying, and why he and other big buyers try to buy gradually, in increments.) Once you own 5 percent of a class of shares, you’ll need to file a report alerting the Securities and Exchange Commission (SEC).

Note also that it can be very costly to buy up all of a company. If you own 2,000 shares, that might seem like a lot. But Nike, for example, has almost 500 million shares outstanding, and you’d need around $30 billion to buy them all.

Keep in mind that a company may only have 10 percent of its value in shares trading publicly. If a firm’s founder, for example, holds 60 percent or 90 percent of the company, then she still controls it.

Q Where can I access earnings reports that companies file with the SEC?

— R.T., Davenport, Iowa

A Many Web sites, such as ours, include access to these filings in their stock data offerings. For example, enter a ticker symbol at http://caps.fool.com and then click on the “SEC Filings” tab. You can also go right to the source at www.sec. gov (look under “Filings & Forms”). You’re smart to look up 10-K and 10-Q reports — they can tell you a lot about a company.

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