If a company has a publicly traded operation in another country, do I benefit? I own America Online (AOL) and Yahoo! (YHOO) , both of which have stocks in other countries, such as America Online Latin America (AOLA) and Yahoo! Japan. Do my shares let me in on this action, or are these companies totally separate? --James Maloney

James,

There are two ways to answer this question: no and yes. No, you don't get a piece of the action, because you don't own any of the stock in AOL Latin America or Yahoo! Japan.

On the other hand, yes, you do get a piece of the action, albeit indirectly. If you own stock in AOL or Yahoo! or another company, you own the whole shebang: the core business, the subsidiaries and the plastic trays in the company's cafeteria.

You get a piece of everything that the company itself owns. You can apply that thinking to these overseas joint ventures, such as AOL Latin America.

Although you're a shareholder in AOL, you didn't receive shares of AOL Latin America, which is a joint venture between AOL and the Venezuelan media company

Cisneros Group

that made its initial public offering Tuesday. (Whether you would actually want a piece of this IPO is another question: AOL Latin America ended its first trading day up a modest 5% from the $8 offering price, which had been drastically lowered last week.)

However, as an AOL shareholder you obviously have an economic interest in whatever AOL owns.

"You aren't going to have any AOL Latin America shares to sell, but you're going to benefit," says Will Landers, director for Latin America Internet equity research at

Credit Suisse First Boston

.

AOL owns just over 40% of AOL Latin America, which provides Internet services in Brazil, Mexico and Argentina. But as a piece of the giant AOL, this venture is minuscule. AOL Latin America has a value of roughly $2.4 billion based on market capitalization, while AOL's market cap is more than $120 billion. Once AOL merges with

Time Warner

(TWX)

, the company's market cap will roughly double.

"AOL Latin America is such a small part of AOL that it really doesn't affect the value of AOL shares," says Eswar Menon, manager of the

Loomis Sayles Emerging Markets

fund.

If you're extremely optimistic toward the prospects of Internet growth in Latin America, you'll probably want more exposure than your AOL stock provides. But by owning AOL, you do have a tiny investment in the region nonetheless.

Your interest in Yahoo! Japan is somewhat similar. Yahoo!, the U.S. company, owns about 34% of Yahoo! Japan, Japan's dominant Internet portal. "By investing in Yahoo!, you're investing in Yahoo! Japan," says Christopher Dixon, entertainment and new media analyst at

PaineWebber

TheStreet Recommends

. (

Softbank

, Japan's biggest Internet company, owns about half of Yahoo! Japan.)

If you wanted to take a direct stake in either AOL Latin America or Yahoo! Japan, you may find buying AOL and Yahoo! themselves easier, since they are traded on the

Nasdaq Stock Market

. (Yahoo! Japan trades in Japan.)

If you own just a few large Internet stocks, you probably have stakes in scores of other companies and ventures. "Many Internet companies take early investment in start-ups in deals where they receive equity," says Dixon. Dixon adds that AOL, for example, has investments in dozens of companies, including

Inktomi

(INKT)

and

Motley Fool,

which is still in private hands.

An investment's material effect on a company's financial results and stock performance really depends on how large that investment is.

When a subsidiary or joint venture goes public, that transaction can help improve the parent company's valuation and stock price. "It segments that one business and focuses investor attention on the value," says Bill Nygren, co-manager of the

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Oakmark and

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Oakmark Select funds.

If large enough, a spinoff or public joint venture could ultimately lead to an increase in the valuation that investors give to the parent, thereby boosting its stock price.

Determining the effect on a parent company's revenue and earnings can be just as tricky. Accounting for these subsidiaries and joint ventures depends on the terms and size of the relationship with the parent and can be incredibly complicated.

If you want to know how investments and ventures affect a stock you own, start by reading Management's Discussion and Analysis in the company's annual report instead of searching through the balance sheet and income statement. This should give you feel for where your company is invested and where it's going.

If a venture or investment is too small to mention, that should tell you something about its relevance.