Facebook has dragged the sex social notworking site Shagbook to court claiming that the outfit has been “damaged by the issuance of a registration for the trademark Shagbook.” Shagbook has now filed its own opposition, along with counterclaims, with the United States Patent and Trademark Office.

Shagbook, in the filing, “denies the allegation that Facebook is highly distinctive as it is a generic term”. It claims that Facebook’s trademark should never have been granted.

Facebook claims that Shagbook site’s name is highly similar in “appearance, sound meaning, and commercial impression”. Its has told the court that the name was adopted with “the intent to call to mind and create a likelihood of confusion … and/or trade off the fame of Facebook”.

According to AP the “Shagbook” name came about when its Shagbook's American owner was living in the UK. He called his “referred to his little black book as his little ‘Shagbook’”. “He was amused with the word ‘shag’, and picked up the name Shagbook.com, all perfectly innocently.”