According to an eSports tracking website, Activision has just purchased "substantially all" of the assets belonging to Major League Gaming. At the moment, this should be considered a rumor, as only a single source has information on it. However, the "proof" does look quite convincing.
If the information is accurate, Activision will have paid a total of $46,000,000 to absorb MLG. That's a hefty sum, but apparently worth it to a company that wants to make a major impact on the market. It's increasingly becoming evident that many game publishers would rather run their own events than partake in someone else's. Valve has seen major success running its own show with Dota 2, and the same goes for Riot Games, with League of Legends.
One thing that this purchase could signify is that it's only worth it to create a league or event if you're looking to get bought out, because with game publishers taking things into their own hands with the biggest franchises out there, there's a risk of non-game publishers tasting little success. If a game company has a title that's successful enough to make a competition event successful, it's no secret why it'd want to handle everything on its own: all of the proceeds go into its own pockets.
The website eSports Observer notes that with this purchase, CEO Sundance DiGiovanni was removed from his position and replaced with Greg Chisholm, who was the company's CFO.
During its life, MLG hosted competitions for some popular games, such as Call of Duty, as well as Activision Blizzard's own StarCraft II. Again, it's best to treat this as a rumor right now, until Activision itself wants to cough up more information.