Nitpick (as you well know) - codice fiscale in Italy differs from USA SSN in that, for once, it has never had AFAIK any semblance of secrecy at all, as you can easily construct it starting from name, surname, place and date of birth [1] Funnily enough, this sometimes results in two individuals computing to the same code [2]

[1] https://en.wikipedia.org/wiki/Italian_fiscal_code

[2] https://it.wikipedia.org/wiki/Omocodia