The Challenge
A mid-size investment bank's compliance team must share transaction reporting data with external auditors and regulators for a MiFID II compliance review. The datasets (XLSX and CSV) contain customer names, IBANs, account numbers, beneficiary identifiers, and individual transaction details. PCI DSS prohibits transmitting full credit card numbers outside the bank's secure perimeter. GDPR requires that personal data in the reports be minimized to what is strictly necessary for the audit purpose. The bank cannot use cloud-based redaction tools due to data sovereignty requirements.
The Solution
The compliance team installs anonym.plus on a dedicated compliance workstation within the bank's secure network segment. They create a Financial Compliance preset targeting: PERSON, EMAIL_ADDRESS, IBAN_CODE, CREDIT_CARD, US_SSN (for US-linked accounts), PHONE_NUMBER, and custom entities for the bank's internal account number format (regex). They use the Mask operator for IBANs (showing only last 4 digits: DE89 **** **** **** 5566) to preserve auditability while removing identifying information. Full names are replaced. The auditors receive a version that allows transaction pattern analysis without exposing individual customer identities.
The Results
- MiFID II audit dataset shared with external auditors — transaction patterns visible, individual identity protected
- PCI DSS requirement met — full credit card numbers not transmitted outside secure perimeter
- GDPR data minimization satisfied — personal data limited to what is necessary for audit purpose
- Data sovereignty maintained — no financial data left the bank's EU infrastructure during processing
- No DPA required with audit firm — anonymized data shared, not personal data
- IBAN masking preserves last 4 digits for transaction reference while removing identifying prefix
Financial Entity Types Supported
| Entity Type | Coverage | Recommended Operator |
|---|---|---|
| IBAN_CODE | All EU country IBAN formats (DE, FR, NL, ES, IT, GB, etc.) | Mask (last 4 visible) or Replace |
| CREDIT_CARD | Visa, Mastercard, Amex, Discover, JCB, Maestro | Replace or Redact |
| PERSON | Account holder, beneficiary, and counterparty names | Replace or Encrypt |
| EMAIL_ADDRESS | Customer and correspondent emails in reports | Replace |
| PHONE_NUMBER | Contact numbers in customer records | Replace |
| US_SSN / national IDs | US and EU national identifiers in multi-jurisdiction reports | Replace or Redact |
| LOCATION / STREET_ADDRESS | Residential and business addresses in KYC records | Replace |
| Custom: account numbers | Bank-specific account number formats via regex | Mask or Replace |
Financial Use Scenarios
- External audits: Share transaction datasets with auditors — individuals anonymized, patterns preserved
- Regulatory submissions: Submit reports to ECB, BaFin, AFM, or FCA — minimize personal data exposure
- Model development: Anonymize customer data before using in credit scoring or fraud detection model training
- Test data sanitization: Replace production IBAN/card data in test environments with structure-preserving labels
- Third-party analytics: Share transaction analytics datasets with data science vendors without customer PII
- AML/KYC archive: Anonymize retained KYC documents after the mandatory retention period (typically 5–7 years)
Read the file anonymization guide. File anonymization guide →
Frequently Asked Questions
How does anonym.plus detect IBANs and credit card numbers?
anonym.plus uses regex pattern matching for IBANs (covering all EU country prefixes and length checks per country) and the Luhn algorithm-validated patterns for credit card numbers across major card schemes. Detection works in text, DOCX paragraphs, XLSX cells, CSV fields, and JSON values.
Can I mask IBANs instead of removing them entirely?
Yes. Use the Mask operator configured to show the last 4 characters: DE89 **** **** **** 5566. The final 4 characters are often used for transaction reference and reconciliation purposes while removing the identifying portion of the account number.