I'm not familiar with the Barclay card. MasterCard has a service called True Name that lets you put whatever you want on your card. It's proprietary but I don't know if they keep it between the two of you. European countries have much stronger privacy protections, though they might have social security numbers which contain sex as an even/odd digit, and it's difficult to change. Checking account numbers are listed in these systems. Banks guard client account line items closely, although in the US the government has blanket access without a warrant.
