Rijksregisternummer

Detects Rijksregisternummer 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

medium

Confidence justification

Medium confidence: pattern has structural constraints but corroborative keywords are recommended to reduce false positive rates. Added context gating and exclusion rules improve precision and reduce incidental matches.

Detection quality

Verified

Jurisdictions

eu, be

Regulations

BDSG, CNIL / LIL, GDPR

Frameworks

ISO 27001, ISO 27701

Data categories

pii, government-id

Scope

wide

Risk rating

5

Platform compatibility

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

Pattern

\b\d{11}\b

Corroborative evidence keywords

identifier, number, ID, ID number, identification, ID card, license, permit, registration, certificate, field, column, row, entry, record, value, form, register, database, extract (+16 more)

Proximity: 300 characters

Should match

• 85010100145 — Standard Belgian national register number
• 90123100234 — Alternate register number
• 00010100456 — 2000-born register number

Should not match

• 1234567890 — Only 10 digits instead of 11
• 123456789012 — 12 digits instead of 11
• 1234567890A — Contains a letter instead of all digits
• template example placeholder record identifier — Template/sample context should be excluded even when anchor words are present

Known false positives

• Long numeric sequences in unrelated contexts (tracking numbers, serial codes) matching the Rijksregisternummer format Mitigation: Use corroborative keywords and, where available, checksum validation to filter false matches.

References

• Belgium national number entity definition - Microsoft Learn

Collections

• European National IDs