The Facebook-Yahoo grudge match continues.
Now Facebook is countersuing Yahoo, denying Yahoo's allegations that Facebook infringed on the company's patents -- and claiming Yahoo is actually infringing on Facebook's patents.
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Facebook's counter-claim, filed Tuesday, denies Yahoo's statements that many of Facebook's tools and features on the site stem from developments made by Yahoo. Facebook requests that any triable issues be taken to court.
The social network also says Yahoo is in violation of some of its patents, including patents the company holds for "generating a feed of stories personalized for members of a social network," and "tagging digital media."
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Facebook says it plans to fight the original lawsuit.
"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," Ted Ullyot, Facebook General Counsel said in a statement.
"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 said it had "a responsibility to its shareholders, employees and other stakeholders to protect its intellectual property."
"This Yahoo stuff feels to me like the business equivalent of when celebs do 'Dancing With The Stars' in a last-ditch effort to save a career," she tweeted.
What do you think about Facebook's counter-suit against Yahoo? Tell us in the comments.
This story originally published on Mashable here.