Some amex cards have a 3 digit cvv [1]. [1] http://ecommerce.shopify.com/c/shopify-discussion/t/heads-up-amex-cards-now-with-3-digit-security-codes-28067 http:

Some amex cards have a 3 digit cvv [1]. [1] http://ecommerce.shopify.com/c/shopify-discussion/t/heads-up-amex-cards-now-with-3-digit-security-codes-28067 http://ecommerce.shopify.com/c/shopify-discussion/t/heads-up...