Yahoo Complaint Feedback Loop service FAQ

Yahoo provides the Complaint Feedback Loop (CFL) service to bulk mail senders and mail list providers to improve the accuracy of their mail lists. By keeping bulk senders informed about how their email is being received by our users, it improves the flow of email for both senders and recipients reducing the amount of unsolicited email our users receive.

Yahoo provides the Complaint Feedback Loop (CFL) service to bulk mail senders and mail list providers to improve the accuracy of their mail lists. By keeping bulk senders informed about how their email is being received by our users, it improves the flow of email for both senders and recipients reducing the amount of unsolicited email our users receive.

Frequently asked questions

What is a "Complaint Feedback Loop"?

When a user clicks the “report spam” button, the message is processed by Yahoo SpamGuard. If the original sender has submitted their domain to the CFL program, Yahoo sends them a copy so they can improve their campaign by removing Yahoo accounts that consider the message to be spam.

It’s recommended that you use a dedicated email address for this purpose.

How does Yahoo determine the sender of a message?

Yahoo uses the domain in your DomainKeys or DKIM signature to determine the original sender because it survives forwarding. This ensures that we can route the report to the correct sender, even if the message was forwarded through another IP address.

If the message isn't signed or the DomainKey or DKIM signature can’t be verified it won’t be included in the CFL.

For bulk commercial senders or senders of transactional mail, DomainKeys or DKIM is the best option.

What does the report look like?

A report is generated in the Abuse Feedback Reporting Format (ARF) every time a Yahoo user marks a message as “spam.” The report includes the message (with full headers, nothing “munged” or redacted), and some additional metadata.

The From: header reads: ‘Yahoo Mail AntiSpam Feedback '.

The SMTP MAIL FROM (envelope sender) is formatted as: ‘cfl.-=@returns.bulk.yahoo.com’.

The source IP address varies, but every report is signed with DomainKeys or DKIM using the signing domain ‘arf.mail.yahoo.com’. That signing domain is only used for that purpose.

Yahoo doesn’t provide sample reports customized for your domain, but there’s an example in the ARF specification linked to above.

As a sender, What do I do with these reports?

The expectation is you'll take steps to reduce the number of complaints. There's many ways to utilize this information to improve your sending status:

Bulk senders or mailing list operators:

  • Proactively maintain your lists:
    • Immediately cease sending additional similar mail to that recipient.
    • Review how that address was added to your list.
      - Adjust processes so the mistake isn't repeated.
    • Determine if the message content led to the report.
  • Honor the frequency of your list’s intent.
    - Was the message expected by the recipient?

Internet Service Providers:

  • Need to determine which of their users sent the message. It’s their responsibility to decide if that user violated their policies, and react appropriately.
  • Actions taken may include:
    • Warning sent to the user.
    • Reduced privileges.
    • Removal from the system.

What if a recipient made a mistake?

Don’t panic. A single complaint won’t automatically get your mail permanently blocked.

If the only reports you get are a few obvious mistakes, you're doing something right.

When lots of recipients complain about the same message, or campaign, you’ll want to investigate why your recipients are marking your message as spam.

Should I sign up with every domain my company owns?

You only need to submit the domains you use to send DomainKeys or DKIM signed messages to Yahoo accounts. For example, If you own both example.com and example.net, but only sign with example.com, you don't need to set up a complaint feedback loop for example.net.

Who do I contact about delivery issues at Yahoo?

You can reach out to our postmaster team by filling out the form at https://postmaster.yahoo.com.

I’m not getting any complaints, but my mail is in the Bulk or Spam folder. Why?

Messages automatically filtered to the Bulk or Spam folder can’t be reported as spam.

When a message is filtered by Yahoo SpamGuard, the recipient would need to check their spam folder to see the email. Automatically filtered messages have met certain criteria to be considered spam by our algorithms.

Are there any other policies that may affect my delivery?

Yes. Yahoo recently updated its policy on how our servers handle DMARC. For more info on what you can do to improve your sending reputation, check out our mail deliverability FAQ.

What do I need to do for the switch from Return Path hosted CFLs to Yahoo hosted CFLs?

Nothing. You’ll continue to get reports for CFLs you set up through Return Path from Yahoo. To add or modify CFLs in future, visit postmaster.yahoo.com and submit a Feedback Loop Application.

Why is Yahoo making the transition from a Return Path hosted CFL to Yahoo hosted CFL?

Yahoo is streamlining customer care and CFL requests by taking over the hosted CFL sign-up page from Return Path. Yahoo and Return Path continue work on other projects such as the Certification program, DMARC and Email Fraud Protection.

If I didn’t save my existing CFL info from the Return Path site is there still a way to get it?

You'll need to contact Yahoo Customer Care to complete your request.

  1. Visit postmaster.yahoo.com.
  2. Click Contact Us | select Product Support.
  3. Enter your info in the required fields.
  4. Click Create Request.

To request CFL data for your domains, submit a New Sender Application.

Can I turn off my CFL service if I no longer want to receive reports?

Yes. To turn off your service submit a CFL application. Under “Request type,” choose the option to Delete reports.

Note: Yahoo only shares the CFL information with authorized users.