We knew that Yahoo was preparing to take "formal action" against Facebook for allegedly violating its social networking and online advertising patents, and AllThingsD is reporting that the company has pulled the trigger today, filing a lawsuit against the social networking giant. Yahoo is quoted with the following statement:

Yahoo! has invested substantial resources in research and development through the years, which has resulted in numerous patented inventions of technology that other companies have licensed. These technologies are the foundation of our business that engages over 700 million monthly unique visitors and represent the spirit of innovation upon which Yahoo! is built. Unfortunately, the matter with Facebook remains unresolved and we are compelled to seek redress in federal court. We are confident that we will prevail.

The move comes after talks between the two companies broke down, with Yahoo reportedly hoping to secure some portion of Facebook's revenues moving forward.

A Facebook spokesperson provided us with the following response:

We're disappointed that Yahoo, a longtime business partner of Facebook and a company that has substantially benefitted from its association with Facebook, has decided to resort to litigation. Once again, we learned of Yahoo's decision simultaneously with the media. We will defend ourselves vigorously against these puzzling actions.

We've reached out to Yahoo for further comment.