Yahoo has warned Facebook that it will face legal action if the social network doesn't sign licensing deals for patents Yahoo believes Facebook is using for its advertising systems, according to reports.
"Yahoo has a responsibility to its shareholders, employees and other stakeholders to protect its intellectual property," Yahoo said in a statement according to various sources, including The New York Times. "We must insist that Facebook either enter into a licensing agreement or we will be compelled to move forward unilaterally to protect our rights."
Facebook said it was not yet able to issue a full response to the claims as it was only just made aware of them.
"Yahoo contacted us at the same time they called The New York Times and so we haven't had the opportunity to fully evaluate their claims," it said.
The stance taken by Yahoo could open up yet another swathe of litigation in the technology sector, where numerous firms including Google, Apple and Microsoft are embroiled in patent battles as firms look to impinge on competitors' ability to operate effectively
Yahoo has struggled in recent years to capture its former success, with previous CEO Carol Bartz fired and replaced by ex-PayPal chief Scott Thompson, while founder Jerry Yang has also left the company.
Is Yahoo looking for some stock in Facebook? That certainly helped end an ongoing patent dispute between Google and Yahoo back in 2004 prior to Google's IPO, along with Google agreeing to license the software Yahoo bought from Overture. Coincidentally, we're approaching Facebook's IPO.