case interview about VCN Handout 1: Virtual Credit Card Number Validation rules Similar to credit card numbers, the digits in virtual card numbers and associated transaction numbers may seem random, but they actually carry meaning. When a Capital One Virtual Credit Card is used, the data must be validated against certain business rules to arrive at a spend decision. These rules are applied to specific digits in the VCN and transaction id. Each transaction made with a VCN is assigned a unique eight (8) digit transaction id.
