Just two weeks after Microsoft bought more than 925 patents from AOL, the company is turning around and selling about 650 of them to Facebook. The deal also allows Facebook to license the other AOL patents that it’s not buying from Microsoft.

According to today’s announcement, the sale will cost Facebook about $550 million — close to half of what Microsoft originally spent on the AOL patents.

Microsoft says the sale is motivated by financial reasons. “Today’s agreement with Facebook enables us to recoup over half of our costs while achieving our goals from the AOL auction,” says Microsoft’s general counsel Brad Smith.

Facebook, on the other hand, has bigger reasons to want the AOL patents: It’s defending itself against Yahoo’s recent patent-infringement lawsuit, a fact that Facebook attorney Ted Ullyot referred to indirectly in his statement about today’s patent buy:

Today’s agreement with Microsoft represents an important acquisition for Facebook. This is another significant step in our ongoing process of building an intellectual property portfolio to protect Facebook’s interests over the long term.

In a statement reported by the New York Times, Yahoo says it sees today’s Microsoft-Facebook agreement as “validation” of its lawsuit against Facebook.

Related Topics: Channel: Industry | Facebook: Business Issues | Facebook: Legal | Legal: Patents | Microsoft: Business Issues | Top News

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