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 investing giant Westfield Capital Management, an investment advisor serving institutions and wealthy investors. It employs deep fundamental research as it seeks out stocks that are underloved by the market, and its funds have outperformed their benchmarks, on average, since inception.

The company's reportable stock portfolio totaled $13.6 billion in value as of June 30, 2012.

Interesting developments
So, what does Westfield Capital's latest quarterly 13F filing tell us? Here are a few interesting details.

New holdings include Nu Skin Enterprises (NYSE: NUS), a Utah-based multi-level marketing company offering personal care products. It recently reporting second-quarter income up 45%, with sales of anti-aging creams selling briskly in China and elsewhere in Asia. While overall revenue rose 40%, revenue in China skyrocketed 150%. The stock took a 13% hit this week, though, on news of allegations that the company is engaging in illegal marketing activities in China.

Among holdings in which Westfield Capital increased its stake were Kraft, Fortinet, and Coach. Blue-chip Kraft has long offered diversification, with both slow-growth grocery items and faster-growing snack foods. But now it's splitting those two businesses into two companies. Computer security specialist Fortinet recently posted a strong quarter, with revenue up 25% over year-ago levels. Luxury handbag maker Coach fell some 17% recently, on disappointing sales in the U.S., despite solid sales abroad.

Westfield Capital reduced its stake in lots of companies, including Halliburton (NYSE: HAL) and Skyworks Solutions (Nasdaq: SWKS). Oilfield services giant Halliburton miscalculated recently when it loaded up on guar gum, a key fracking ingredient in short supply. But supply rose, and prices fell. Still, the company is performing well and seeing rapid revenue growth internationally. Skyworks, a smartphone ingredient maker, has benefited from the explosive growth of iDevices, with some worrying that it's rather dependent on one key customer. Others point out that it actually serves many other markets, such as the automotive, medical, avionics, and military ones, among others.

Finally, Westfield Capital unloaded several companies, such as Alpha Natural Resources (NYSE: ANR) and NII Holdings (Nasdaq: NIHD). Alpha Natural Resources has fallen about 75% over the past year, due to low coal prices. The company has cut back on production, but its future doesn't look rosy in the near term, at least while natural gas prices are low. (Many utilities are switching to producing electricity with gas instead of coal these days.) Still, its long-term prospects may be decent. NII Holdings, meanwhile, has plunged 81%, focusing on delivering wireless services to enterprises in Central and South America. Revenue has been flat lately, but earnings have dropped as the company invests in its network -- though even there it's a bit behind the times, offering 3G technology in a world increasingly interested in 4G.

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. 13-F forms can be great places to find intriguing candidates for our portfolios.

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