A system or method that assesses a transaction request from a client to identify characteristics that are likely to indicate fraudulent behavior, based on data associated with the request and the client, including client data that is obtained from a social network, such as Facebook. The assessed characteristics may include the client's social profile, including number and status of friends, likes, and virtual account status, as well as parameters associated with the connection used for the transaction, such as IP and email addresses, country of origin, and language. A database is maintained that includes records associated with IP and e-mail addresses, users' characteristics and past redemptions, and the like. Specific criteria, limits, and responses may be defined for each particular class of transaction.