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 David Einhorn, highly regarded value investor and founder of Greenlight Capital. Einhorn's investing success, as well as his advocacy of financial transparency and accountability, has attracted many fans. Although he isn't afraid to short stocks, he prefers going long, looking for situations where he feels a stock is mispriced. He started Greenlight with less than $1 million, and it now boasts a stock portfolio worth more than $5 billion. Greenlight Capital has averaged close to a 20% annual return since its 1996 inception.

Greenlight Capital's latest 13F report shows that it boosted its positions in BP (NYSE:BP), Anadarko Petroleum (NYSE:APC), and Take-Two Interactive Software (NASDAQ:TTWO).

Beleaguered oil giant BP yields 4.7%, but that doesn't make it appealing enough to buy for some investors. The company's fourth quarter featured net income down 30% over year-ago levels, due in part to weak refining margins, its divestment program, and Deepwater spill-related costs. BP has sold many assets to generate needed funds, but its ultimate total spill-related costs remain unknown. The company has retained a promising project portfolio, though, and it boasts strong reserve replacement ratios. A new worry is Russia and the upheaval in Ukraine, as BP has investments in the region. (One positive for BP, however, might be stronger interest in a pipeline to Europe that bypasses Ukraine.) In some ways, BP still looks more attractive than its peers, as it has been shrinking its debt and rewarding shareholders.

Anadarko Petroleum has a profitable oil business and is expanding in natural gas. The situation in Ukraine may benefit Anadarko if it boosts demand for natural gas. Meanwhile, its production in Colorado has been growing and delivering its biggest U.S. returns, while the Wolfcamp field in West Texas is also very promising. Some have worried about Anadarko's liabilities related to the Tronox titanium dioxide pigment company that was spun off from Kerr-McGee, a company that Anadarko acquired, but others feel those worries are already factored into its price to a large degree.

Take-Two Interactive is known to many for its Grand Theft Auto franchise, and rightly so. The Grand Theft Auto V game was 2013's best seller, and it's among the top-selling games of all time. Take-Two's NBA2K basketball game franchise is also a strong performer. It recently announced plans to shut down its Irrational Games subsidiary, which is behind the Bioshock Infinite game. With a forward P/E ratio near 11, Take-Two Interactive seems attractively priced as well, though bears worry about the company's inconsistent sales growth and question its ability to keep churning out megahits.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.