New Complaint Feedback Loops Available from Synacor and FastMail

Continuing the growth of our global Receiver Alliance, Return Path is pleased to announce the deployment of two new feedback loop services for our partners Synacor and FastMail. With the addition of these services, Return Path now hosts and manages 10 of the 13 public complaint feedback loops available today.

These feedback loops enable an ISP’s or mailbox provider’s customers to report spam via their web-based mail service, custom email client, or possibly through a help desk. The ISPs use this data first to improve their own spam filters, and can in turn report their customer complaints to fellow ISPs or bulk senders who have registered and been approved to receive the reports. A more detailed description is available in this article from last year.

The Return Path feedback loop operations and management service enables ISPs and mailbox providers to create a complete spam reporting mechanism for their customers and registered feedback loop participants. The Return Path service handles all the sign-up and routing details, from setting up the feedback loop process to managing the daily approval requests and reporting, thus enabling our partners to focus on their customer experience.

A registration page is available to ISPs, senders, and other entities who wish to register for these feedback loops. The registration page facilitates the approval of the application prior to receiving feedback. Upon approval, Return Path will begin to receive the complaints from our partners and will pass the reports to the approved participants using the industry-standard Abuse Reporting Format.

By allowing senders and peers access to this complaint data, Synacor and FastMail demonstrate their commitment to providing a superior experience for their customers and to making email work better for everyone.

Synacor offers a robust, customizable, and secure email solution for a large number of ISPs, including Qwest, Century Link, WideOpenWest and many others. Synacor’s new complaint feedback loop is at

FastMail has been providing email services for the past 10 years for thousands of companies and a large customer base. FastMail’s new complaint feedback loop is at

The Return Path Receiver Alliance is an open data cooperative that includes the top email providers worldwide, serving over 2.1 Billion mailboxes. It offers a range of benefits to support the daily management of large-scale inbound mail streams.

Return Path also hosts complaint feedback loops for:

In all cases, the ISP or mailbox provider makes all decisions of eligibility for participation in their feedback loop service.

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