Peer to Peer (P2P) software developer StreamCast Networks this week added online TV firm Joost to its legal hit list.

StreamCast originally filed suit against Skype in March 2006, alleging that the company had misappropriated intellectual property. The lawsuit was amended to include eBay – Skype’s owner – and 21 other defendants later in the year.

Joost has been added to the filing alongside its owners, Niklas Zenstromm and Janus Friis – who also founded Skype and Kazaa – in a suit for $12.3bn in damages.

“The sale of Skype to eBay was made possible through a scheme by many of the defendants to misappropriate the FastTrack peer-to-peer technology that rightfully belongs to StreamCast,” said outside counsel Dan Woods, a partner at the global law firm of White & Case LLP, acting on behalf of StreamCast.

“We’ve now added the offshore entity known as Joost as a defendant to this lawsuit. Zennstrom and Friis may have been trying to mainstream themselves but they can hide from these claims no longer,” he said.

The suit alleges that the original Kazaa co-founders, Zennstrom and Friis, profited handsomely from the sale of Skype to eBay after they secretly transferred away the rights to the FastTrack technology in violation of a license agreement that provided StreamCast a right of first refusal to acquire the technology.

StreamCast is seeking to stop the sale and marketing of Skype’s services and the new online P2P television venture Joost.