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. It manages money for more than 100 large institutions, and its strategy involves macroeconomic research and fundamental analysis. You may know Fisher by his longtime column in Forbes magazine, where he's also No. 243 in the magazine's list of the 400 richest Americans, with a net worth of $2.3 billion. You may know his father, as well: Phil Fisher wrote the seminal investing text Common Stocks, Uncommon Profits.

The company's reportable stock portfolio totaled $43.4 billion in value as of March 31, 2014.

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

New holdings of interest include electric-car company Tesla Motors (TSLA 0.10%). The stock got a boost this week when CEO Elon Musk spoke of strong demand and plans to build cars in China, which would expose the company to a huge market and also avoid hefty import tariffs there. As the company tries to keep up with demand, it's also establishing a plant in California. Tesla's fourth quarter featured revenue up some 150% and earnings blasting past expectations. It's aiming to bring down battery costs by building a massive "Gigafactory." Tesla's Model S was rated as practically perfect by Consumer Reports last year.

Among holdings in which Fisher Asset Management increased its stake were Caterpillar (CAT 0.36%) and Baidu (BIDU -0.67%). The world's largest maker of construction and mining equipment has been struggling in recent years, in part due to weakness in China, and it reduced its workforce by 7% over the past year. It just reported its first-quarter results, with estimate-topping earnings up 10% (or 23% excluding restructuring charges) over year-ago levels -- though revenue was roughly flat. Bulls are hopeful about the company's plan to strengthen its important dealer network, and they see Caterpillar's fortunes improving if mining and infrastructure work picks up. Less exciting is that it has become the target of a U.S. Senate investigation into whether it improperly avoided taxes by shifting billions of dollars of profits to low-tax countries. The stock yields 2.3%

China-based search-engine giant Baidu has risen about 80% over the past year. It just reported its first-quarter results last night, topping earnings expectations and meeting revenue projections. Revenue surged 59% over year-ago levels, while net income rose 24%. Baidu is reportedly talking with Chinese travel-booking specialist Ctrip.com about some kind of business combination. Meanwhile, Baidu seems to be gaining ground in the mobile arena.

Fisher Asset Management reduced its stake in lots of companies, including Sirius XM Radio (SIRI 0.98%) and Gilead Sciences (GILD 0.51%). Sirius XM Holdings also just posted its first-quarter results, featuring revenue up 11% over year-ago levels and non-GAAP earnings up 54%. There was a net gain of subscribers of 267,000, and the CEO noted, "New car installations and trial conversions set first quarter records." Bulls see paths to international expansion via streaming, while bears worry about rate hikes and competition from free and Internet radio services.

Gilead Sciences reported its first-quarter results earlier this week, blowing away expectations with boffo sales for its new Hepatitis-C drug, Sovaldi. That's very exciting, but between its steep price tag (about $84,000 for a 12-week course) and competition, sales might not skyrocket long. Sales of Gilead's HIV drug Stribild have also been growing rapidly, and it might achieve blockbuster status soon, too. (Gilead is a leader in HIV treatments, which generate much of its revenue.)

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