Update - Yahoo: Facebook’s AOL patent deal with Microsoft show it is weak 
 
 As expected, Facebook and Microsoft today announced Menlo Park will pay Redmond $550 million for a portion of the 925 U.S. patents and patent applications it recently acquired from AOL for $1.056 billion. “This is another significant step in our ongoing process of building an intellectual property portfolio to protect Facebook’s interests over the long term,” Ted Ullyot, general counsel of Facebook, said in a statement. Facebook subsequently countersued Yahoo, in a pattern that is playing out again and again in different parts of the technology business, especially the mobile phone market. Google has menaced Microsoft’s business on a number of fronts, including with free online Google applications that compete with Microsoft Office and with Android, a mobile operating system that competes with Microsoft’s Windows Phone software. “This may be a case of the enemy of my enemy is my friend,” he added. Microsoft will retain ownership of approximately 275 AOL patents and applications, a license to the approximately 650 AOL patents and applications that will now be owned by Facebook, and a license to approximately 300 patents that AOL did not sell in its auction. If the deal announced Monday clears regulatory scrutiny, Microsoft would still own about 275 AOL patents and retain a license to the 650 patents that Facebook will own. Facebook will not, however, get a license to the 300 patents AOL still retains and which Microsoft has licensed. I said Microsoft would not directly help Facebook: 
 
 Microsoft and Yahoo have a patent sharing deal through their 2009 search agreement, which has been extended till 2013.
– Earlier this month, AOL agreed to sell Microsoft 925 patents and patent applications for just north of $1 billion; now another tech giant is getting a piece of the action. Facebook has pledged to buy some 650 of those patents, or $550 million worth. In the deal, Facebook also gets a license to Microsoft's portion of the portfolio. According to Facebook's announcement, Microsoft ends up with 275 AOL patents, plus licenses to Facebook's AOL patents and the 300-ish patents AOL didn't sell. "Today’s agreement with Facebook enables us to recoup over half of our costs while achieving our goals from the AOL auction," says a Microsoft rep. For Facebook, it's "another significant step in our ongoing process of building an intellectual property portfolio to protect Facebook’s interests over the long term," says a spokesman. What do outsiders say? "The deal is a further sign of the growing importance of stockpiling patents in the arsenal of any big technology company," writes Nick Wingfield for the New York Times. "It also shows how Microsoft and Facebook have gravitated increasingly closer to each other in large part because of a common enemy: Google." Writing for ZDNet, Emil Protalinski says it's actually all about Yahoo, not Google. "With public companies like Yahoo targeting it for patent infringement, the social networking giant has stepped up its game. I don’t believe it’s a coincidence that AOL and Yahoo are such similar companies. This is exactly why Facebook is so interested in AOL’s patents: a lot of them cover technologies that Facebook uses, as well technologies used by companies that want to sue Facebook."