If account ownership verification is your concern, then the digits of a credit card offer relatively little assurance. Fun story: I used to work for a company t

If account ownership verification is your concern, then the digits of a credit card offer relatively little assurance. Fun story: I used to work for a company that utilized the last four of a CC on file for verification. They also let anyone pay an outstanding balance without needing to otherwise verify, and kept the last four of the card on file. So...