The majority of them do. A few do not. The standard 36/28-inch griddles do. Remove the griddle top and gently lay the griddle base on its back. Remove the bottom tray with the Thumbscrews and then fold the left leg first and then the right leg, securing the legs with the spring loaded leg lock.
Any ProSeries, Griddle+, and Culinary series griddles are not going to fold for transport.