RFC 5965, "An Extensible Format for Email Feedback Reports", August 2010

Errata ID: 3120
Status: Held for Document Update
Type: Technical
Publication Format(s) : TEXT
Reported By: John Levine
Date Reported: 2012-02-14
Held for Document Update by: Pete Resnick

Section 2.d. says:

This part MUST be included (contrary to [REPORT])

It should say:

This part MUST be included if the entity creating the report has 
received the message.

Notes:

Reports can be created from info collected in SMTP transactions that don't accept a message, a scenario we didn't consider when we wrote this section.

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