# Yahoo Complaint Feedback Loop (CFL)

> How Yahoo's DKIM-domain-based Complaint Feedback Loop works: enrollment via Sender Hub, ARF report format, and operational rules.

Source: emailmarketing.net — https://emailmarketing.net/learn/providers/yahoo-complaint-feedback-loop

If you send mail to Yahoo users, you can receive a report each time one of them marks your message as spam. Yahoo's Complaint Feedback Loop (CFL) sends these reports in **ARF (Abuse Reporting Format)**.

The reports let you **suppress complainers from further campaigns** and adjust your targeting and frequency. This matters because spam votes directly damage sender reputation, and count toward Yahoo's 0.3% complaint threshold (see [Yahoo Sender Requirements](https://emailmarketing.net/learn/providers/yahoo-sender-requirements)).

## Key properties

| Property | Value |
|---|---|
| Basis | **Domain-based, DKIM only.** Only mail signed with DKIM is supported, because DKIM is how Yahoo identifies the sender actually responsible |
| IP-based FBL | **Not offered.** Yahoo no longer supports CFL reporting based on IP addresses or CIDR ranges |
| Report format | ARF |
| Coverage | All consumer domains hosted by Yahoo, including AOL (thousands of hosted domains) |
| Who should enroll | Bulk email senders. ESPs usually enroll DKIM domains on behalf of their clients |

## Enrollment (via Sender Hub)

1. **Create your Sender profile** on Yahoo Sender Hub (senders.yahooinc.com).
2. **Add and verify your domains**: the DKIM `d=` domains you sign with.
3. **Enroll each domain** in the CFL.

Notes:

- Enrollments made through Yahoo's **old form, from before Sender Hub, did not carry over**. You had to enroll again through Sender Hub. ARF reports for old enrollments stopped on **August 1, 2024**, with no grace period.
- The **reporting address can be any email address you control**. Ownership is verified during enrollment, and you can reuse the same verified address to enroll more domains.
- Enrolling the organizational domain does not enroll all its subdomains. **ARF reports are sent for the enrolled DKIM domains that match the signature** on the message that received the complaint. Enroll each signing domain.
- To check the status of enrollments, edit them or delete them, go to **Manage Services**, then **Complaint Feedback Loop**, in your Sender Hub profile.

## Report mechanics

- All reports use the **Abuse Reporting Format (ARF)** and contain **at least three MIME parts**: a plain-text part, machine-readable metadata in MIME format, and the headers of the original message.
- Report messages arrive with:
  - From header display name: **"Yahoo! Mail AntiSpam Feedback"**
  - SMTP sender: **feedback@arf.mail.yahoo.com**
  - A DKIM signature with the domain **arf.mail.yahoo.com** (verify the signature before you trust the reports or automate actions on them)
- When a message has several DKIM signatures, Yahoo evaluates all of them for the CFL (and also for DMARC alignment and reputation).

## Operational use

- **Automate suppression.** Parse incoming ARF reports, and immediately unsubscribe or suppress the recipient who complained. Continuing to mail people who complained adds to the reputation damage.
- **Monitor the complaint rate.** Comparing CFL volume with the volume delivered to Yahoo is the practical way to track your position against the 0.3% threshold. The `complaints` metric in the [Performance Feeds](https://emailmarketing.net/learn/providers/yahoo-performance-feeds) gives an aggregate view.
- **Diagnose segments.** A spike in ARF reports after a change in content, frequency or audience identifies the campaign or segment at fault.

## Related articles

- [Yahoo Sender Requirements](https://emailmarketing.net/learn/providers/yahoo-sender-requirements), including the 0.3% complaint threshold
- [Yahoo Deliverability Performance Feeds](https://emailmarketing.net/learn/providers/yahoo-performance-feeds), for aggregate complaint and placement metrics
- [Foundations of Email Deliverability](https://emailmarketing.net/learn/foundations/foundations-of-email-deliverability), on how complaints affect reputation