Social networking giant Facebook has filed a lawsuit against Shagbook in the United States, claiming the adult dating site’s name is too closely aligned to its own.
Facebook also alleges Shagbook will damage Facebook’s reputation "by the issuance of a registration" of its name.
Shagbook has fired back with a countersuit, claiming Facebook is bullying its competitors and added that the company should never have been issued the trademark.
A spokesman for Shagbook has said the name for the website came about innocently enough. The site’s owner referred to his "little black book" as his "shagbook", and, as he was amused by the word "shag", the site spun off from there.
Shagbook, which was established in 2006, is latest of several companies to have been hit with a lawsuit from Facebook. The social network has a history of aggressively targeting organisations it believes have infringed on its trademark, such as Teachbook and FacebbookOfSex.com.