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 Fisher Asset Management, founded in 1979 by Ken Fisher. You may know Fisher by his longtime column in Forbes magazine, where he's also No. 263 in the magazine's list of the 400 richest Americans, with a net worth of $1.7 billion. You may know his father, as well: Phil Fisher wrote the seminal investing text, Common Stocks, Uncommon Profits.

The reportable stock portfolio of Fisher's company totaled a whopping $37.5 billion in value as of March 31, 2012. The company manages money for more than 100 large institutions, and its strategy involves macroeconomic research and fundamental analysis.

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

New holdings include Diamond Foods (Nasdaq: DMND), which has seen its stock plunge 73% over the past year. The company has been investigated for improper payments to walnut growers, failed to report three quarterly reports on time, suspended its dividend, was unsuccessful in its attempt to buy Pringles from Procter & Gamble, and faces delisting from the Nasdaq market. That's enough to make some run away, but others simply see the stock as having fallen into bargain territory -- provided it successfully turns itself around.

Among holdings in which Fisher Asset Management increased its stake were Cliffs Natural Resources (NYSE: CLF) and TriQuint Semiconductor (Nasdaq: TQNT). Iron ore producer Cliffs has been struggling, with rising labor costs and fuel expenses putting pressure on its profits. Another concern is slowing growth in China -- but even when slowed, China is still growing, and Cliffs has been rewarding shareholders with massive dividend increases in the past few years.

TriQuint, meanwhile has been cut roughly in half over the past year, but in its favor it's supplying components for iPads, which bodes well for success. (Although it is risky for a company to depend too much on any other company for a big chunk of its revenue.) TriQuint does have other customers, but they include beleaguered mobile phone makers Nokia (NYSE: NOK) and Research In Motion. The company also has other businesses, such as supplying network infrastructure projects.

Fisher Asset Management reduced its stake in a lot of companies, including Exelon (NYSE: EXC) and Nokia. Exelon is the nation's top nuclear power company, and offers a fat dividend topping 4%. But low natural gas prices have disrupted many utilities, and nuclear power's reputation has been tarnished by the disaster in Japan. Still, Exelon carries less debt than many peers, and as a utility providing a very necessary good, it's a defensive investment.

Nokia, meanwhile, has been posting some ugly results over the past few years, unsuccessfully fighting the iPhone and other competitors. To survive, its latest plan is to focus on low-end smartphones, while cutting tens of thousands of jobs. Will it work? Stay tuned...

Finally, Fisher Asset Management unloaded several companies, such as Patriot Coal and Endeavor Silver. Patriot shares have imploded, plunging 94% over the past year, as coal use has fallen, due partly to the low price of natural gas. Endeavor has gained 20% and remains promising to those who expect high silver prices.

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.

If you'd like to profit off the trillion-dollar mobile revolution with stocks other than Nokia or even TriQuint, check out this free special report to learn about the surprising star of the mobile revolution.