Andreas Arvanitakis, senior analyst at Point Carbon, says an obvious starting point is improving the security of the computer systems with encryption and more layers of protection. "Some of the national registries are less safe than a hotmail account," he says. "Each of the allowances has a serial number but sales happen so quickly in a few clicks that they are long gone before they can be traced. A buyer on an exchange could be completely unaware they are handling stolen goods. The big question now is what happens to the victims of this and the eventual owners of the credits. Who pays? Is the buyer left liable? "