Taiwan Passport Number

Detects Taiwan passport number 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. Context label evidence plus explicit template/example exclusion improves precision for high-risk identifiers. Added context gating and exclusion rules improve precision and reduce incidental matches.

Detection quality

Verified

Jurisdictions

tw

Frameworks

ISO 27001, ISO 27701

Data categories

pii, government-id

Scope

narrow

Risk rating

8

Platform compatibility

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

Pattern

\b\d{9}\b

Corroborative evidence keywords

passport, travel document, passport number, ID number, identification, ID card, license, permit, registration, certificate, field, column, row, entry, record, value, form, register, database, extract (+19 more)

Proximity: 300 characters

Should match

• 301234567 — Nine-digit passport number
• 987654321 — Nine-digit passport number
• 456789012 — Nine-digit passport number

Should not match

• 12345678 — Only 8 digits is too short
• 1234567890 — Ten digits is too long
• sample template placeholder number 123456789 — Template/sample context should be excluded even when numeric-like values appear
• template example placeholder record identifier — Template/sample context should be excluded even when anchor words are present

Known false positives

• Generic alphanumeric sequences matching passport format in unrelated contexts. Mitigation: Require corroborative evidence keywords within the proximity window.

References

• Taiwan passport number entity definition - Microsoft Learn