Worse, there are some reports that it sends not just what you copy, but everything you select..
And Tynt provides no opt outs. Not cookie based, not IP based, but stop it you creeps angry phone call based.
It ain't a pure useful service, and it ain't a pure privacy invasion. But I sure wish they'd go away and have had the decency to never start up in the first place. I block it on Firefox with Ghostery.