AHV-Nummer

Detects AHV-Nummer patterns. This pattern is based on a Microsoft Purview built-in sensitive information type. Users already running Purview may prefer to enable the built-in SIT directly, or use this version as a starting point for customisation.

Type

regex

Engine

universal

Confidence

high

Confidence justification

High confidence: pattern has strong structural constraints (specific format, prefix, or character class restrictions) that significantly reduce false positive rates.

Detection quality

Verified

Jurisdictions

ch

Frameworks

ISO 27001, ISO 27701

Data categories

pii, government-id

Scope

narrow

Risk rating

9

Platform compatibility

Purview: Compatible, GCP DLP: Compatible, Macie: Compatible, Zscaler: Compatible, Palo Alto: Compatible, Netskope: Compatible

Pattern

\b756\.\d{4}\.\d{4}\.\d{2}\b

Corroborative evidence keywords

AHV, AVS, sozialversicherungsnummer, social security, ID number, identification, ID card, license, permit, registration, certificate

Proximity: 300 characters

Should match

• 756.1234.5678.90 — Swiss AHV number
• 756.9876.5432.10 — Another AHV number
• 756.4567.8901.23 — Valid AHV format

Should not match

• 757.1234.5678.90 — Wrong country prefix (757)
• 756.1234.5678.9 — Too few digits in last group

Known false positives

• The 756 prefix (Switzerland country code) and dot-separated format provide strong structural validation. Mitigation: The country prefix and structured format significantly reduce false positives. Keyword context provides additional confidence.
• In multiple languages, similar terminology used in formal or administrative contexts (education, professional documentation) that does not constitute sensitive data collection. Mitigation: Layer with additional contextual signals such as structured identifiers, form fields, or database column headers to distinguish sensitive records from general references.

References

• Swiss Social Security Number AHV entity definition - Microsoft Learn