# UBL-DT-12

Source: https://xmlvalid.com/rules/UBL-DT-12

> Format attribute should not be present

- Level: warning
- Rule sets: EN 16931 rules (UBL) 1.3.17, EN 16931 rules 1.3.16 (UBL), EXTENDED-CTC-FR rules (UBL) 1.4.0.04, Romanian RO e-Factura rules (UBL) 1.0.9
- Context: `/ubl:Invoice | /cn:CreditNote`
- Test: `not(//@format)`

Validate a document against these rules: https://xmlvalid.com/validate