Hi All,

Mailgunner here, a couple of notes:

* The case outlined in this blog post is related to incoming email forwarding feature, not Mailgun outbound sending.

* General email forwarding case does not break Mailgun's DKIM signature.

* Forwarding is tricky as long as it modifies content and we have lots of edge cases with our customers, and we are always working on improving on edge cases like this one.

* This is an edge case where the email has been forwarded from Mailchimp -> Mailgun -> Gmail and we have some conflicting content with Mailchimp's original email causing the DKIM signature failure.

* Mailgun sending pipeline team is looking at the issue to get more detail about that.

Thanks everyone!