Attestwire › Rule reference › BR-DE-28

BR-DE-28 The seller email address must look like an email address

noun · XRechnung · warning · BT-43

Your invoice carries a warning because the contact email address does not have the form of an email address. Usually a display name sits in front of it, or several addresses share one field; give a single, bare address. KoSIT rates this a warning, so the invoice is accepted. In the standard the field is BT-43, and BR-DE-28 is the rule that checks the form.

Diese Regel auf Deutsch: BR-DE-28 — auf Deutsch erklärt.

Business term

BT-43 — Seller contact email address

Severity

warning

Applies to

xrechnung-ubl, xrechnung-cii

The fix

Put a single, bare email address into seller.contact.email: no display name, no angle brackets, no list.

What the rule requires

What is checked is the form of BT-43. KoSIT’s rule text asks for exactly one @, at least two characters on each side of it, neither a space nor a dot directly beside it, and no dot at the start or the end.

By far the most common trigger is a display name: Buchhaltung <rechnungen@example.de> is a valid header in an email program, but not a valid value for BT-43. Neither is a comma-separated list of addresses.

In this library the field is seller.contact.email.

In BT-43 soll genau ein @-Zeichen enthalten sein, welches nicht von einem Leerzeichen, einem Punkt, aber mindestens zwei Zeichen auf beiden Seiten flankiert werden soll. Ein Punkt sollte nicht am Anfang oder am Ende stehen.

A passing value

"email": "rechnungen@example.de"

Why it exists

BT-43 is processed by machine: the authority writes to this address. What a person reads effortlessly as an address with a name in front is, to a mailing system, an invalid string. The check catches it before the first query goes nowhere.

What the library returns

The full error returned by @attestwire/en16931. It includes the rule ID, affected field and suggested correction. Developers can use this object in their application:

{
  "rule": "BR-DE-28",
  "field": "BT-43",
  "severity": "warning",
  "message": "The seller contact email address (BT-43) must contain exactly one \"@\", flanked by at least two characters on each side and by neither a space nor a dot, and must not begin or end with a dot. \"Buchhaltung <rechnungen@acme.example>\" does not satisfy that shape.",
  "fix": "Supply a single, plain email address — no display name, no angle brackets, no comma-separated list.",
  "example": "\"email\": \"rechnungen@example.de\"",
  "xpath": "/ubl:Invoice/cac:AccountingSupplierParty/cac:Party/cac:Contact/cbc:ElectronicMail",
  "docsUrl": "https://attestwire.com/rules/BR-DE-28"
}

xpath is always a UBL path. On a CII invoice, look for the matching CII field instead.

How our check differs

See also: BR-DE-7 — the rule that requires the field at all; BR-DE-27 — the same kind of shape check for the telephone number.