ibr-co-20
If Invoice line period (ibg-26) is used, the Invoice line period start date (ibt-134) or the Invoice line period end date (ibt-135) MUST be filled, or both.
What the rule checks
As the rule set's publisher wrote it. The rule runs on every element the context matches, and fails where the test is false; the validator reports the line of that element.
cac:InvoiceLine/cac:InvoicePeriod | cac:CreditNoteLine/cac:InvoicePeriod
exists(cbc:StartDate) or exists(cbc:EndDate)
Checked with PINT SG Invoice, PINT SG Credit Note, PINT JP Invoice, PINT A-NZ Invoice, PINT A-NZ Credit Note, PINT MY Invoice, PINT MY Credit Note