Re: Maybe I'm not as smart as these card tech guys...
Well typically it's not a hash, because that won't allow fuzzy matching that takes into account small changes between different presentations of the same finger. MasterCard say that they convert the fingerprint to a template and store it in an encrypted form on the card. Of course the encryption key needs to be stored on the card too, but hopefully it is not easy to extract both it and the encrypted template.
Biting the hand that feeds IT
