It's not very often that Warren Buffett's Berkshire Hathaway sells a company, and even rarer when it sells a company that it just bought less than a year ago. So it seems a bit intriguing that Berkshire has decided to unload almost 30% of its stake in Suncor (NYSE:SU) after making the initial purchase back in the second quarter of 2013. 

One possibility for unloading shares of Suncor could be because Berkshire Hathaway wants to dedicate more of its capital to its largest energy holding, ExxonMobil (NYSE:XOM). The combined sell-off of both Suncor and ConocoPhillips (NYSE:COP) is just about equal to the number of shares that were picked up in Exxon, which would suggest that Berkshire doesn't want more exposure to the energy market than it already has. Tune in to the following video to find out why Berkshire might be more in love with Exxon than with any of its other energy holdings.