I had my first experience with Certigy when I was totally humilliated at a Walgren store. When my check was declined, I made them let me call Certigy and made everyone in the store wait while they asked all the confirming information and still would not clear my check. I was told my check writing habits alerted them and there was nothing negative to make them decline my check. I subsequently had them send me "an application" so I could write checks where ever they did business. Filled the paperwork out and haven't heard from them. Two more times I have since had this problem at Publix and Ross Dept Store. I don't know how I got in their system or how to find out what stores use them. It is really a humiliating experience. I have to say I had a heated discussion with them by phone after my Publix experience since this has never happened their before. How do you get out of their system? Wish I knew.