The latest 13F season is here, when many money managers issue required reports on their holdings. It can be worthwhile to pay attention, as you might get an investment idea or two by seeing what some major investors have been buying and selling.

For example, consider Bridgewater Associates, one of the world's largest hedge fund companies. According to its recently released 13F statement, the company has reduced or eliminated its positions in Hewlett-Packard (NYSE:HPQ), Broadcom (NASDAQ: BRCM), and Micron Technology (NASDAQ:MU).

Hewlett-Packard has struggled in recent years, but its stock doubled in 2013 and it's up by double digits so far this year. The printing giant has been hurt by the weak PC market, with shrinking revenue to show for it, while earnings have risen in part due to aggressive cost-cutting. The company's turnaround strategy includes enormous layoffs, to the tune of about 45,000 to 50,000 jobs, with some worrying whether it's cutting bone along with fat. (It hasn't been cutting its R&D spending, though.) A bright spot is its hefty free cash flow, topping $8 billion annually. Hewlett-Packard bulls like its moves into areas such as 3-D printing and in health care analytics, as well as its 1.9% dividend yield. The company's forward price-to-earnings ratio of 8.6 is appealing, but Hewlett-Packard's future is rather uncertain.

Broadcom is a telecom chipmaker whose stock has averaged 3% annual growth over the past decade. It did pop close to 10% recently, though, when the company announced that it's giving up on its low-margin cellular business (which some think Apple might want to buy). A bit of good news is that Broadcom is working with Apple on its HomeKit home-automation technology that should appear in this year's iOS8. Bulls are hopeful about its investments in the infrastructure, mobile, and wearable-computing arena. Bears don't like the company's deteriorating financials and disappointing recent quarterly results -- but many of these numbers could change for the better soon. Broadcom's stock yields 1.3%.

Micron Technology's stock has surged some 130% over the past year, and its P/E ratio is still just near 12, suggesting that it's attractively priced. It offers a lot of reasons to be bullish, such as stabilizing prices, expected continued demand growth for memory, and Micron's presence in iPhones, which are likely to experience a surge in sales with the upcoming debut of the iPhone 6. Some expect the company to start paying a dividend again, as its free cash flow is substantial and profit margins are growing. There are still some worries, though, such as the commoditization of memory, the risk of falling prices, and tough competition.