Editor's Note: A previous version of this article erroneously attributed the founding of Tiger Global Management to Julian Robertson, who founded the unrelated hedge fund Tiger Management. Charles Coleman, who once worked for Robertson, founded Tiger Global Management. The author and the Fool regret the error.

Every quarter, many money managers have to disclose what they've bought and sold via 13F filings. Their latest moves can shine a bright light on smart stock picks.

Today let's look at Tiger Global Management. The company's reportable stock portfolio totaled $5.9 billion in value as of March 31, 2012. 

The fund's massive portfolio is highly concentrated, owning only a few dozen stocks. The portfolio's top three holdings, representing a whopping 41% of its assets, were Russian search giant Yandex, Apple, and Google.

Interesting developments
So what does Tiger Global Management's latest quarterly 13F filing tell us? Here are a few interesting details:

New holdings include Deckers Outdoor (Nasdaq: DECK) and Frontier Communications (Nasdaq: FTR). Deckers, maker of footwear such as the popular UGG boots, is down 40% over the past year, putting it into bargain territory in the eyes of some investors. Bulls like its hefty profit margins and dearth of debt, and its diversification; it owns not only the UGG brand, but also Teva and Sanuk, and it has been a longtime solid grower of revenue and earnings.

It might be less clear why an investor would load up on shares of Frontier Communications, since the rural-focused telecom company saddled itself with lots of landlines in an increasingly mobile-phoned world. It's also saddled with debt and has been losing customers. Its 10% dividend yield is certainly attractive, but note that the company recently cut its payout. It's not a lost cause, as its revenue growth has been accelerating and averaged about 20% annually over the past five years, and insiders have been buying, too. Still, there are less risky alternatives than Frontier.

Among holdings in which Tiger Global Management increased its stake was Arcos Dorados Holdings (NYSE: ARCO). Down 30% over the past year, it's the exclusive franchiser of McDonald's restaurants in Latin America and the Caribbean -- regions with economies growing much faster than ours. It already operates some 1,800 eateries, and some of our analysts like it so much that they've added shares of it to their real-money portfolios. The stock was recently whacked due to lower operating results, higher foreign exchange losses, and higher tax charges, but the company's long-term prospects seem rosy.

Tiger Global Management reduced its stake in Amazon.com (Nasdaq: AMZN). There's always a lot to like about Amazon, such as its growing footprint in our retail landscape and its innovations fueling growth, such as its Kindle, its promising cloud-computing services, and its Amazon Prime membership program featuring streaming videos and fast, free shipping. But investors get hung up on its valuation, which always seems too high. Recently, for example, the company's P/E ratio topped 185, and its forward P/E was still 69, considerably higher than the S&P 500's 13.

Finally, Tiger Global Management unloaded several companies, such as Heckmann (NYSE: HEK), which specializes in delivering and processing water. It has generated a lot of income from serving the growing fracking practice of natural-gas companies, but the low price of the gas has put a damper on that. Heckmann is turning more attention to more profitable shale oil projects, and is also buying the oil recycler Thermo Fluids. There's plenty to like about Heckmann, but right now it carries a lot of debt and is cash-flow negative.

We should never blindly copy any investor's moves, no matter how talented the investor. But it can be useful to keep an eye on what smart folks are doing, and 13-F forms can be great places to find intriguing candidates for our portfolios.

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Longtime Fool contributor Selena Maranjian, whom you can follow on Twitter, owns shares of Apple, Amazon.com, and Google, but she holds no other position in any company mentioned. Click here to see her holdings and a short bio. The Motley Fool owns shares of Arcos Dorados Holdings, Amazon.com, Google, Apple, and Heckmann. Motley Fool newsletter services have recommended buying shares of Amazon.com, Apple, Google, and Deckers Outdoor, as well as creating a bull call spread position on Apple. The Motley Fool has a disclosure policy. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days.