The present invention relates to a method for operating a security device, wherein the security device is part of a charging device for charging an energy store of a vehicle, preferably an electric vehicle or hybrid vehicle. The security device is connected to an Internet-capable server. In a first step of the method, the security device reads the vehicle service data. In a second step of the method, the security device compares the vehicle service data via the server with a database of vehicles which have been reported stolen. Finally, the security device sends a signal to the charging device if the vehicle is entered as stolen in the database.