Why is there an increase in Yahoo FBL reports starting July 6th?
Matthew Whittaker
Co-founder & CTO, Suped
Published 4 Jun 2025
Updated 17 Aug 2025
7 min read
Email Feedback Loops (FBLs) are crucial for senders, providing vital insights into how recipients perceive their emails. These reports notify you when users mark your messages as spam, helping you maintain a healthy sender reputation. Ignoring FBL data can lead to serious deliverability problems, including being blocklisted (or blacklisted) by Internet Service Providers (ISPs).
Recently, many email senders have observed a notable increase in Yahoo FBL reports beginning around July 6th. This sudden uptick has naturally raised concerns about potential new issues affecting email deliverability or a spike in user complaints.
It's important to investigate such anomalies promptly to understand their root cause and determine if any action is needed. This article will explore the likely reasons behind this observed increase and what steps you can take to ensure your email program remains robust.
Understanding email feedback loops
Feedback loops are a cornerstone of email deliverability, acting as a direct communication channel between ISPs and legitimate senders. When a recipient at an ISP like Yahoo marks an email as spam, the FBL system relays that information back to the sender. This allows senders to identify problematic campaigns, remove disengaged users from their lists, and ultimately improve their sender reputation and inbox placement.
FBL data is critical for understanding your audience's engagement and avoiding being flagged as a spammer. A sudden surge in these reports could indicate that your content is being perceived as irrelevant or unsolicited by a larger segment of your audience, or it could point to an issue with your sending practices.
However, it's crucial to differentiate between an actual increase in user complaints and an increase in the *volume of FBL reports themselves*. Sometimes, an ISP might update its FBL system or processes, leading to more frequent or more detailed reports being sent, even if the underlying complaint rate hasn't changed. This distinction is vital for accurate diagnosis.
The new Yahoo FBL system and reporting
The increase in Yahoo FBL reports starting around July 6th appears to be related to internal system changes at Yahoo. Their postmaster team indicated they were investigating a spike in complaint feedback loop volume. This suggests the observed increase is more likely a result of Yahoo's complaint feedback loop system coming fully online or being adjusted, rather than a sudden spike in actual spam complaints from users.
Some senders who had previously noted unusually low FBL volumes or issues receiving reports through the new setup saw the July 6th date as a sign that the system was finally stabilizing and delivering reports as expected. This aligns with the understanding that the FBL reports indicate volume is up, rather than a necessarily higher complaint rate.
It's also worth noting that Yahoo (and Google) implemented new email requirements earlier in 2024, emphasizing sender authentication and reduced spam rates. These changes might also have played a role in the adjustments to their FBL infrastructure, leading to reporting shifts as the ecosystem adapts.
In some cases, senders reported receiving multiple FBLs for the same complaint, suggesting a potential duplication issue with the new system rather than an increase in unique complaints. Yahoo's postmaster team acknowledged this and worked on a fix.
Investigating potential causes
While the observed increase might be a reporting adjustment, it's still essential for senders to confirm their FBL registrations and monitor their email performance closely. Older FBL registrations might have expired or required re-registration, which could also contribute to perceived fluctuations in report volume.
A genuine increase in complaints, even if not the primary cause of this specific event, is a critical signal. It suggests potential issues such as:
List quality degradation: Sending to unengaged or old addresses can lead to more spam complaints or hits on spam traps. Regularly cleaning your list is key.
Content relevance: If your emails don't meet recipient expectations, they might mark them as spam.
Missing unsubscribe options: Make it easy for users to opt out. If they can't find an unsubscribe link, they will resort to the spam button. Gmail's new unsubscribe feature makes this even more critical.
Maintaining deliverability amidst changes
Even if the specific July 6th Yahoo FBL increase was a reporting anomaly, maintaining strong email deliverability practices is paramount. Here’s what you should do:
Enroll in FBLs: Ensure all your sending domains are properly enrolled in the Verizon Media Group (which includes Yahoo and AOL) Complaint Feedback Loop (CFL) program. This is your primary source for complaint data.
Monitor FBL data: Regularly review your FBL reports to identify trends, not just spikes. Look for consistent high complaint rates or specific campaigns that generate more complaints.
Maintain list hygiene: Promptly remove recipients who mark your emails as spam from your mailing lists. Regularly clean your lists to remove inactive or invalid addresses, reducing bounces and spam trap hits. This also helps with issues like Yahoo 'mailbox not found' bounces and Gmail 'mailbox full' bounces.
Implement strong authentication: Ensure your emails are properly authenticated with SPF, DKIM, and DMARC. This is increasingly important for major ISPs like Microsoft, Gmail, and Yahoo.
While the July 6th increase in Yahoo FBL reports was likely a system adjustment rather than a true spike in complaints, it serves as a valuable reminder of the importance of continuous monitoring and proactive email deliverability management. Staying informed about ISP changes and maintaining robust sending practices will always be your best defense against deliverability challenges.
Looking ahead
The increase in Yahoo FBL reports on July 6th initially caused concern among senders. While it appears to have been a correction or adjustment in Yahoo's FBL system and not a true increase in complaints, this event underscores the dynamic nature of email deliverability. Vigilant monitoring of your metrics, understanding ISP nuances, and maintaining strong authentication and list hygiene practices are essential for ensuring your emails consistently reach the inbox.
Views from the trenches
Best practices
Actively enroll all your sending domains in relevant Complaint Feedback Loops, including Yahoo's, to receive direct spam complaint data.
Regularly cross-reference your FBL data with your internal engagement metrics to get a holistic view of email performance.
Implement a robust list hygiene strategy to promptly remove unengaged subscribers and avoid hitting spam traps.
Prioritize email authentication (SPF, DKIM, and DMARC) to build and maintain strong sender reputation with ISPs.
Stay informed about updates and announcements from major ISPs like Yahoo, Google, and Microsoft regarding their email policies.
Common pitfalls
Misinterpreting an increase in FBL report volume as an increase in actual spam complaints without further investigation.
Neglecting to re-register FBLs after system changes or expiration, leading to a loss of critical feedback data.
Failing to integrate FBL data into your suppression lists, which can result in continued sending to complaint-prone recipients.
Not reacting quickly to FBL data, allowing minor issues to escalate into significant deliverability problems.
Overlooking the importance of explicit consent and transparent unsubscribe options in email campaigns.
Expert tips
Monitor FBL volume and actual complaint rates separately to distinguish between reporting adjustments and genuine user feedback.
Automate FBL processing to ensure real-time suppression of complaining users from your mailing lists.
Use FBL data to segment your audience and tailor content to improve engagement and reduce future complaints.
Collaborate with your email service provider (ESP) or deliverability team to troubleshoot any persistent FBL anomalies.
Regularly test your email setup, including authentication, to ensure compliance with evolving ISP requirements.
Marketer view
Marketer from Email Geeks says they have seen graphs indicating an increase in Yahoo FBL volume, which aligns with observations from other senders.
2024-08-07 - Email Geeks
Marketer view
Marketer from Email Geeks says they love the new Yahoo FBL system because it helped them detect malicious activity related to their signup forms.
Yahoo marks an email as spam, the FBL system relays that information back to the sender. This allows senders to identify problematic campaigns, remove disengaged users from their lists, and ultimately improve their sender reputation and inbox placement.
Yahoo. Their postmaster team indicated they were investigating a spike in complaint feedback loop volume. This suggests the observed increase is more likely a result of Yahoo's complaint feedback loop system coming fully online or being adjusted, rather than a sudden spike in actual spam complaints from users.
Google) implemented new email requirements earlier in 2024, emphasizing sender authentication and reduced spam rates. These changes might also have played a role in the adjustments to their FBL infrastructure, leading to reporting shifts as the ecosystem adapts.
Verizon Media Group (which includes Yahoo and 
Microsoft, 
Gmail, and Yahoo.
