[KarlInOhio]

Simple piece of aluminum foil, 2X the size of the license. Fold once. Problem solved.

I doubt that will completely stop all signals, but rather just attenuate them by a certain amount thus shortening the range at which it can be detected. Maybe you can shorten the range enough so that they have to be inside your pocket to detect it in your wallet. I would rather have something like a small drill and a drop of acid to kill the RFID chip or antenna.

[Wonder Warthog]

"I doubt that will completely stop all signals, but rather just attenuate them by a certain amount thus shortening the range at which it can be detected."

Remember, RFID cards get their DRIVE ENERGY from the triggering RF in order to send out their info. They don't have on-board batteries. No power, no signal.

Perhaps someone with access to an RFID reader could test.