Yesterday Yahoo filed a lawsuit against Facebook claiming that Facebook had used 10 of Yahoo’s patents. Some of the patents include methods and systems for advertising, Instant Messaging (IM) and a few over technologies that are important to Facebook.

The 10 Patents include methods and systems for advertising, Instant Messaging, News feed, and other technologies that make Facebook what Facebook is today.

Yahoo are Suing Facebook just weeks before they are due to cash in with it’s initial public offering of stock which is somewhat of a coincidence since Yahoo did something similar back in 2004 when Yahoo sued Google over the use of Adwords technology that was originally owned by Overture, a company that Yahoo had recently bought at the time. Eventually Yahoo won the battle and received 2.7 million shares of stock which they then later sold to make $1.5 billion.

Yahoo have left this statement to explain why they are suing Facebook “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.”

Facebook are thought to be puzzled as to why Yahoo want to do this after Facebook sends a lot of traffic to Yahoo and has helped them over the years in attracting new users. A Facebook spokesperson has said this “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. Once again, we learned of Yahoo’s decision simultaneously with the media. We will defend ourselves vigorously against these puzzling actions.”