# F-LIB024

Source: https://xmlvalid.com/rules/F-LIB024

> There must be a FirstName if the FamilyName is not present

- Level: error
- Rule sets: OIOUBL 2.1 Invoice rules (Denmark) 1.17.2, OIOUBL 2.1 Credit Note rules (Denmark) 1.17.2, OIOUBL 2.1 Reminder rules (Denmark) 1.17.2
- Test: `(not(cbc:FamilyName) or cbc:FamilyName = '') and (not(cbc:FirstName) or cbc:FirstName = '')`

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