MASHABLE - Apr 4 - 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. Facebook 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.” Facebook says it plans to fight the original lawsuit. Yahoo formally went after Facebook in March, claiming the company violated 10 of its patents.