Facebook is playing the Yahoo vs. Facebook lawsuit by the book. Facebook, in its turn, has counter sued Yahoo for infringing on 10 of its patents. This move was predicted by Erin-Michael Gill, the chief intellectual property officer for MDB Capital. "Facebook is following the playbook," he said. "They're doing exactly what potentially Facebook investors would expect them to do. They're leveraging the IP that they've acquiring the past few years. They're putting their best assets on the table and now can engage in negotiations from a far stronger position."

Ted Ullyot, Facebook's General Counsel, said, "From the outset, we said we would defend ourselves vigorously against Yahoo's lawsuit, and today we filed our answer as well as counter-claims against Yahoo for infringing ten of Facebook's patents.... While we are asserting patent claims of our own, we do so in response to Yahoo's short-sighted decision to attack one of its partners and prioritize litigation over innovation."

Yahoo has sued Facebook because Yahoo has been unable to keep up in the changing landscape of the modern internet. They used to be an internet pioneer, but have fallen behind with the times. They are losing the search wars to Google. The counterclaim paints a different picture. Facebook is claiming that they are the damaged party. They want the court to dismiss Yahoo's case and award Facebook damages.

Facebook claims that Yahoo is infringing on patents via functions that are major contributors to Yahoo's revenue stream. The patents in question are:

• U.S. Patent No. 7,872,208 which covers "generating a feed of stories personalized for members of a social network" issued Nov. 2, 2010.
• U.S. Patent No. 7,945,653 covering "tagging digital media" which was issued May 17, 2011.
• U.S. Patent No. 6,288,717 entitled "Headline Posting Algorithm" issued Sept. 11, 2001.
• U.S. Patent No. 6,216,133 entitled "Method for Enabling a User to Fetch a Specific Information Item from a Set of Information Items and a System for Carrying Out Such a Method" issued April 10, 2001.
• U.S. Patent No. 6,411,949 entitled "Customizing Database Information for Presentation with Media Selections" issued on June 25, 2002.
• U.S. Patent No. 6,236,978 entitled "System and Method for Dynamic Profiling of Users in One-to-One Applications" issued May 22, 2001.
• U.S. Patent No. 7,603,331 entitled "System and Method for Dynamic Profiling of Users in One-to-One Applications and for Validating User Rules" issued Oct. 13, 2009.
• U.S. Patent No. 6,288,717 entitled "Headline Posting Algorithm" issued Sept. 11, 2001.
• U.S. Patent No. 8,005,896 entitled "System for Controlled Distribution of User Profiles Over a Network" issued August 23, 2011.
• U.S. Patent No. 8,150,913 entitled "System for Controlled Distribution of User Profiles Over a Network" issued April 3, 2012.