Please establish a Feedback Loop agreement with Google and provide the data from the Google Feedback Loop for messages sent to gmail addresses.

This could be done either by:

Allowing administrators to customize email headers to place header and fields as specified by Google (Feedback-ID: a:b:c:SenderId; see https://support.google.com/a/answer/6254652?hl=en);

Or by automatically including the header code with fields tied to each email send (ex. using em_id as an identifier).

Receiving feedback on spam complaints tied to specific campaigns or email sends would be helpful to ensure inbox placement--especially since, as the Luminate Online FAQs point out: "Gmail, for instance, relies primarily on user engagement and feedback to rank senders."