Yahoo has filed an intellectual property lawsuit¹ against Facebook.

雅虎投诉Facebook侵犯其知识产权。

Yahoo claims the social network has infringed² 10 of its patents including systems and methods for advertising³ on the web. Facebook denies the allegation.

The move comes ahead of Facebook's planned flotation later this year.

Patent litigation（诉讼） has become common between the smartphone makers⁴, but this marks a new front in the battles between the tech giants.

A statement from Yahoo suggested the web portal believed it has a strong case.

"Yahoo's patents relate to cutting edge innovations in online products, including in messaging, news feed generation, social commenting, advertising display, preventing click fraud and privacy controls," its suit said.

"Facebook's entire social network model, which allows users to create profiles and connect with, among other things, persons and businesses, is based on Yahoo's patented social networking technology.

The social network signalled that it believed that Yahoo had not tried hard to settle the matter without involving the courts. It described Yahoo's action as "puzzling".

"We're disappointed that Yahoo, a longtime business partner of Facebook and a company that has substantially benefited from its association with Facebook, has decided⁵ to resort to litigation," it added.