Yahoo Inc sued Facebook Inc over 10 patents that include methods and systems for advertising on the Web, opening the first major legal battle among big technology companies in social media. The lawsuit, filed in a San Jose, California federal court on Monday, marks a major escalation of patent litigation that has already swept up the smartphone and tablet sectors and high-tech stalwarts such as Apple Inc, Microsoft Corp and Motorola Mobility Holdings Inc. Yahoo's patent lawsuit follows Facebook's announcement of plans for an initial public offering that could value the company at about $100 billion. Facebook spokesman Jonathan Thaw said Facebook learned of the lawsuit through the media, and he stated "we're disappointed that Yahoo, a longtime business partner of Facebook and a company that has substantially benefited from its association with Facebook, has decided to resort to litigation," he said. In an emailed statement, Yahoo said it is confident it will prevail. "Unfortunately, the matter with Facebook remains unresolved and we are compelled to seek redress in federal court," the company said in a statement. Yahoo, one of the Web's pioneering companies, has seen its revenues decline in recent years at a time when rivals such as Facebook and Google have thrived. In January, Yahoo appointed former PayPal President Scott Thompson as its new chief executive, replacing Carol Bartz, who was fired in September, as Reuters stated. Yahoo said late last month it was seeking licensing fees from Facebook over its patents and that other companies have already agreed to such licensing deals.
