Twitter has bowed to legal pressure and given-up the details of five of its users, as part of a landmark libel case.
The social networking site has been ordered to hand-over the details in an attempt to unmask an anonymous tweeter, accused of posting libelous messages about members of South Tyneside council.
The order could have implications in the controversy which saw scandal-hit, Premier League footballer Ryan Giggs named on Twitter despite an injunction banning his naming.
Giggs' alleged affair with a reality TV star was later revealed in parliament, but his lawyers are believed to be chasing the details of thousands of individual Twitter users who initially breached the court order.
Twitter last week insisted that it would not protect its members in the face of legal demands from the authorities, which means the South Tyneside case could aid the efforts of the Welshman's legal team.
Lawyers for the councilors who claim to have been libeled by an anonymous poster known only as "Mr Monkey" took their efforts to a California court, which has jurisdiction over Twitter
Media lawyer Mark Stephens told Sky News: "Ryan Giggs' lawyers went to the High Court in London which doesn't have jurisdiction over Twitter in California.
"Whereas the 9th Circuit court where the Tyneside council went in California does have jurisdiction over Twitter, so Twitter had no alternative but to hand over the material."
Be careful what you Tweet, guys. Ill-behaved, rich celebrities are going after your freedom of speech and Twitter isn't going to shield you.