FINDINGpii.
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A Finnish henkilötunnus — a valid century sign, a valid mod-31 check character, and a plausible date — appears in the free text.
What it looks at#
An 11-character DDMMYY + century sign + 3-digit individual number + 1 check character.
The sign between the date and the individual number encodes the century — + for
1800-1899, - (and a small set of legacy letters) for 1900-1999, A-F for 2000-2099 —
and the trailing character must match the standard mod-31 check computed from the date
and individual number.
Why it matters#
The henkilötunnus is Finland’s national identifier, used across banking, healthcare and government services — high severity for the same reason as the Swedish and Norwegian equivalents.
What to do#
High severity. Redact before storing or forwarding.