# PEPPOL-T01-R027

Source: https://xmlvalid.com/rules/PEPPOL-T01-R027

> The Item gross price SHALL NOT be negative.

- Level: error
- Rule sets: Peppol Order rules 3.7
- Context: `cac:Price`
- Test: `(cac:AllowanceCharge/cbc:BaseAmount) >= 0 or not(exists(cac:AllowanceCharge/cbc:BaseAmount))`

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