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 Tiger Global Management. The tech-oriented  hedge fund company's reportable stock portfolio totaled $7.4 billion in value as of March 31, 2014, and contained just a few dozen stocks. Indeed, the top 10 holdings make up about 61% of the overall portfolio's value.

Tiger Global's latest 13F report shows that it decreased or eliminated its positions in, (NASDAQ:AMZN), Bitauto Hldg Ltd (NYSE:BITA), and Netflix (NASDAQ:NFLX). has seen its shares slide some 25% from its 52-week high, and given its forward P/E of 61  and a current P/E near 480, many are still calling it overvalued. They've done that for many years, though, while the stock has averaged annual returns of 20% over the past decade. Amazon has had some negative press lately: It's engaged in a standoff with publisher Hachette and has been referred to by some as a bully. Those paying attention to labor issues will know that it has also been accused of having harsh working conditions in its warehouses, and workers in Germany are striking. Amazon is still growing its top line by double digits annually, though, and has many new initiatives under way, such as its cloud-computing services, its Fire TV video streaming device, its streaming music service, and its AmazonFresh grocery delivery service. Bears worry about slowing growth and rising taxes and would like to see greater profitability now rather than somewhere down the line.

Bitauto Holding is an Internet content and services company focused on China's auto industry and working closely with dealers. Tiger Global loaded up on Bitauto shares just last quarter, but with shares having quadrupled in value over the past year, perhaps the stock just seems a bit pricey at recent levels. Bulls are excited about the company's potential, given the Chinese auto industry's brisk growth rate and expectations of robust global growth in the coming years, much of it from China. Bears worry  about a possible stock pullback if growth rates slow -- and the company's last quarter did reflect a sequential slowdown, though it also surpassed earnings estimates. Profit margins have been on an upswing in recent years, and first-quarter revenue surged 48% year over year.

Netflix is dominating the online streaming arena. As it shifted its focus from DVD rentals to streaming video, its profit margins have swelled, and it's tacking on millions of new subscribers regularly, while pushing hard into Europe, Canada, and elsewhere. Netflix does face deep-pocketed competition, though, and its success hasn't come cheap, as it has spent much of its cash to secure existing content while also developing exclusive programming such as Orange Is the New Black. With a forward P/E ratio near 70, its stock doesn't look cheap, but 70 is still well below its five-year average P/E of 125. The company's recent news includes deals to stream classic HBO content and a partnership with DreamWorks.