Summary
The consensus from experts and marketers is that feedback loop information is generally not public domain. It is primarily an agreement between senders and mailbox providers to facilitate the forwarding of spam complaints for better email list management and improved sender reputation. While there's a possibility of information leaks, sender subscriber data within platforms like uFBL is typically available to Mailbox Provider partners via UI but not exported publicly. Crucial steps for protecting deliverability and sender reputation include implementing SPF, DKIM, and DMARC, especially for private email servers, consistently sending valuable content, monitoring blocklists, and ensuring DKIM keys are appropriately sized. Documentation emphasizes the importance of standardized formats for feedback reports, different levels of data feed accessibility, and proactive authentication measures.
Key findings
- FBL Privacy: Feedback loop information is generally not public domain but an agreement between senders and mailbox providers.
- Subscriber Data Access: Sender subscriber data is typically available to mailbox providers via a UI within certain platforms but not via public export.
- Authentication Importance: SPF, DKIM, and DMARC are crucial for preventing email spoofing and establishing sender validity.
- Report Utilization: Standardized feedback reports are used for automated processing of spam complaints.
- Data Feeds: Data feeds exist in both public and private forms, depending on the provider.
- Reputation Maintenance: Consistently sending valuable content and monitoring blocklists contribute to maintaining a good sender reputation.
Key considerations
- Data Security: While feedback loop data is not public, consider potential leaks and secure the information appropriately.
- Authentication Practices: Implement and regularly update SPF, DKIM, and DMARC records to protect against spoofing and improve deliverability.
- Content Strategy: Focus on providing valuable and engaging content to minimize spam complaints.
- Monitoring and Management: Actively monitor feedback loop data and blocklists to proactively manage sender reputation.
- DKIM Configuration: Ensure that DKIM keys are of an adequate length (2048 bits or higher) to meet current security standards.
What email marketers say
10 marketer opinions
Feedback loops are agreements between senders and mailbox providers, facilitating the forwarding of spam complaints to the sender for list management and improved deliverability. While subscriber information may be available to mailbox provider partners through UIs, it is not generally exported or considered public domain. Implementing SPF, DKIM, and DMARC is crucial for authentication and preventing email spoofing, particularly for private mail servers. Consistently sending valuable content, avoiding spam triggers, actively monitoring blocklists, using dedicated IPs, and properly configuring DKIM keys are essential practices for maintaining a good sender reputation and enhancing email deliverability.
Key opinions
- FBL Purpose: Feedback loops enable senders to identify and remove subscribers who mark emails as spam, improving sender reputation.
- Data Privacy: Sender subscriber information is available to Mailbox Provider partners through a UI, but not via exported data functions, implying limited public access.
- Authentication Importance: SPF, DKIM, and DMARC are essential for preventing email spoofing and validating senders to mailbox providers.
- List Hygiene: Feedback loops help with list hygiene by identifying users who mark mail as spam.
- Reputation Factors: Sending valuable content, avoiding spam triggers, and removing unsubscribed recipients improve IP reputation.
- DKIM Key: A DKIM key of 2048 bits is recommended for secure email authentication.
Key considerations
- FBL Implementation: Understand the feedback loop mechanism to effectively manage spam complaints and improve list quality.
- Authentication Protocols: Implement and maintain SPF, DKIM, and DMARC records, especially for private email servers, to enhance security and sender reputation.
- Content Quality: Focus on sending valuable and engaging content to avoid spam complaints and maintain a positive sender reputation.
- List Management: Actively monitor and remove unsubscribed recipients to avoid being flagged as spam.
- IP Reputation: Regularly monitor blocklists and consider using a dedicated IP address for better control over sender reputation.
- DKIM Configuration: Ensure DKIM keys are of adequate length (2048 bits) to maintain email security standards.
Marketer view
Email marketer from EmailDeliverabilityBlog.com says actively monitoring blocklists, using a dedicated IP address, and segmenting your email list can lead to good sender reputation.
31 Aug 2024 - EmailDeliverabilityBlog.com
Marketer view
Email marketer from Reddit shares if you run your own private mail server. You need to ensure you have SPF, DKIM and DMARC setup.
28 Apr 2025 - Reddit
What the experts say
3 expert opinions
Experts consistently state that feedback loop information is not considered public domain. Feedback loops are agreements between senders and mailbox providers, where complaints are forwarded privately to the sender for reputation management. While the possibility of information leaks exists, the core data remains non-public.
Key opinions
- Non-Public: Feedback loop information is generally not public domain.
- Sender-Provider Agreement: Feedback loops are agreements between senders and mailbox providers.
- Reputation Management: Feedback loops help manage sender reputation by identifying spam complaints.
Key considerations
- Data Security: While not public, be mindful of potential data leaks and secure the information accordingly.
- Private Agreement: Understand that feedback loops are private agreements for improving deliverability.
- Reputation Monitoring: Use feedback loop data for proactive reputation management and list hygiene.
Expert view
Expert from SpamResource explains feedback loops are an agreement between a sender and mailbox provider where the mailbox provider forwards complaints to the sender, not public.
14 Aug 2021 - SpamResource
Expert view
Expert from Email Geeks responds that he doesn’t believe the feedback loop information becomes public domain, but whether and how much it leaks is another issue.
28 Jul 2022 - Email Geeks
What the documentation says
4 technical articles
Technical documentation outlines the structure and use of feedback reports, email authentication mechanisms, and data feed availability. Standardized formats for feedback reports facilitate automated processing. Data feeds can be either publicly available or private, and SPF records help prevent email spoofing. DMARC aggregate reports provide information on email sources and authentication results.
Key findings
- Standardized Format: Email feedback reports follow a standardized format for automated processing.
- Data Feed Variation: Data feeds exist in both public and private forms.
- Spoofing Prevention: SPF records prevent email spoofing.
- Aggregate Reporting: DMARC aggregate reports offer insights into email sources and authentication checks.
Key considerations
- Report Utilization: Use standardized feedback reports to address unsolicited email complaints efficiently.
- Data Feed Access: Determine whether public or private data feeds are appropriate for your needs.
- SPF Implementation: Implement SPF records to prevent email spoofing.
- DMARC Analysis: Analyze DMARC aggregate reports to identify and address authentication issues.
Technical article
Documentation from DMARC.org explains DMARC aggregate reports contain information about the sources sending email using your domain and the results of authentication checks.
26 Dec 2022 - DMARC.org
Technical article
Documentation from ietf.org specifies that SPF records should be setup to prevent email spoofing.
29 Dec 2023 - ietf.org
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