If you've followed international stocks over the past few years, you've surely noticed a trend: Foreign companies delisting their stocks from major U.S. exchanges.

In fact, well-known foreign companies such as British Airways, Fiat, and Bayer have either announced or implemented their departure from the NYSE in recent weeks.

And we can expect this flight from New York to continue.

It's nothing personal; it's just business
This spring, U.S. regulators made it a lot easier for foreign companies to deregister their shares, and many companies have capitalized on the opportunity. Why, you ask? Put simply, the extra costs of following Sarbanes-Oxley (SOX) and various exchange regulations, as well as anemic trading volumes on U.S. exchanges, often outweighed the benefits for these companies.

Professors Joseph D. Piotroski and Suraj Srinivasan at the University of Chicago Graduate School of Business recently studied this phenomenon and discovered that, since SOX was passed in 2002, "The frequency of foreign listings on the NYSE and Nasdaq has fallen by nearly 63%. ... In contrast, the frequency of foreign listings on the (London Stock Exchange) has more than doubled since the Act."

Piotroski and Srinivasan also noted that smaller foreign companies in particular are avoiding NYSE or Nasdaq listings because U.S. regulatory costs can have a significant impact on their bottom lines.

While some larger companies have also packed their bags, you're unlikely to see large foreign firms with high daily trading volume -- think CVRD (NYSE:RIO), Baidu.com (NASDAQ:BIDU), or Petrobras (NYSE:PBR) -- leaving Wall Street anytime soon. In these cases, it's more cost effective (and good public relations) to be listed in the States.

The good news is that you still have access to foreign companies that have delisted their shares: You can pick them up via the Pink Sheets.

Oh, the humanity!
While the Fool typically dissuades investors from patrolling the Pink Sheets, using it to purchase foreign shares is an exception. Trading guidelines for these over-the-counter shares (place only limit orders, etc.), however, should still be followed.

Here are three foreign firms that trade on the Pink Sheets and deserve your attention:

  1. CSR (CSRXF): This Cambridge, U.K.-based firm designs more than half of the world's Bluetooth chips, sports an impressive balance sheet ($185 million in cash and no long-term debt), and grew its bottom line 33% in 2006. The company competes with Broadcom (NASDAQ:BRCM) and supplies a who's-who list of tech companies such as Apple (NASDAQ:AAPL) and Dell (NASDAQ:DELL) with its Bluetooth chips.
  2. Wal-Mart de Mexico (WMMVY): As the largest retailer in Mexico, Wal-Mart de Mexico (Walmex) has plenty of room to expand in a growing economy. The region also seems to be more accepting of Wal-Mart's brand and operating methods, so this is not likely to be a repeat of Wal-Mart's failed and expensive attempt to penetrate the German market.
  3. Lukoil (LUKOY): If you're in the market for a large oil conglomerate and can handle the extra political and economic risks associated with Russia, Lukoil is worth your attention. It has the world's second-largest hydrocarbon reserves behind only ExxonMobil (NYSE:XOM), has grown net income by 33% per year on average over the past five years, and posted a 25% return on equity in 2006.

Before you press the "buy" button ...
Even though following SOX and U.S. exchange regulations can be costly for companies, it's important to note that these regulations were largely designed to protect shareholder interests by requiring greater disclosure and adherence to U.S. GAAP. As such, it can be much more difficult to interpret financial statements and estimate a valuation for non-U.S.-listed firms.

Yet simply ignoring non-U.S.-listed foreign companies for this reason would be folly. The growth potential is just too great, and, with the trend of foreign companies delisting their shares, the foreign stocks you own today may be off the U.S. exchanges down the road.

If you'd like some help navigating the complex international markets, Motley Fool Global Gains is here for you. Fool senior analyst Bill Mann and the Global Gains team take the time to explain the intricacies of the global markets and teach you what to look for and what to avoid.

You can see all of their past recommendations and receive two new stock ideas each month with a free 30-day trial to Global Gains. Simply click here to take advantage of our offer. There is no obligation to subscribe.

Fool contributor Todd Wenning commemorated "Talk Like a Pirate Day" on Sept. 19 by wearing arrrgh-yle socks. He does not own shares of any company mentioned. Wal-Mart de Mexico is a Global Gains pick. Wal-Mart and Dell are Inside Value choices. Dell is also a Stock Advisor recommendation. Petrobras is an Income Investor selection and Baidu.com is a Rule Breakers pick. The Fool's disclosure policy is full of booty.