Summary
Maintaining a public spammer list is legally complex and expensive, akin to running a credit agency. Defamation, antitrust, and data protection laws apply, necessitating accuracy and transparency. Spammers rapidly adapt, making list maintenance difficult. Data privacy concerns arise when tracking spammers using personal data. ESPs use tools like Spamhaus RBLs, SURBL, and bot management, and techniques like honeypots, data validation, and feedback loops. Domain reputation services, comprehensive reputation systems (e.g., Talos Intelligence), and tracking user consent also play a role. Dedicated IP addresses allow senders to build independent reputations. Collaborative efforts, internal vetting, and discussions, plus adhering to RFC 5782 for abuse reporting, are also important.
Key findings
- Legal Risks & Costs: Maintaining a public spammer list presents significant legal risks (defamation, antitrust) and is financially demanding.
- Dynamic Spammer Tactics: Spammers constantly evolve, making it challenging to keep spammer lists accurate and current.
- Data Privacy Concerns: Collecting and processing personal data to identify spammers raise substantial privacy issues.
- RBLs & SURBL: Spamhaus RBLs and SURBL are valuable resources for blocking known spam sources and malicious URLs.
- Reputation Systems: ESPs use domain reputation services and comprehensive systems like Talos Intelligence to evaluate senders.
- Honeypots & Data Validation: Honeypots and data validation are effective techniques for identifying spammers and removing invalid addresses.
- Feedback Loops & Consent: Feedback loops with email providers and tracking user consent are crucial for compliance and deliverability.
- Bot Management: Bot management tools are used to combat spamming bots.
- Standardized Reporting: RFC 5782 provides a standardized format for reporting email abuse, facilitating collaboration.
- Dedicated IPs: Dedicated IP addresses give senders control over their sending reputation.
Key considerations
- Legal Compliance: Thoroughly understand and comply with defamation, antitrust, and data protection laws.
- Accuracy & Updates: Invest in resources to ensure spammer lists are accurate and regularly updated.
- Privacy Safeguards: Implement robust privacy safeguards when handling personal data to identify spammers.
- Multi-Layered Approach: Employ a multi-layered approach, combining RBLs, reputation systems, honeypots, data validation, and feedback loops.
- Collaboration & Reporting: Foster collaboration among ESPs and adhere to standardized abuse reporting formats (RFC 5782).
- Consent Management: Prioritize obtaining and tracking explicit user consent for sending emails.
- Reputation Monitoring: Use tools like Google Postmaster Tools to proactively monitor and improve sending reputation.
- Bot Protection: Implement bot management solutions to protect against spamming bots.
- Dedicated IPs: Consider using dedicated IPs to establish and control sender reputation.
What email marketers say
9 marketer opinions
Maintaining a public spammer list presents several challenges and legal risks. Key challenges include keeping the list accurate and up-to-date due to spammers' evolving tactics. Legal risks involve potential lawsuits related to defamation and antitrust issues. ESPs employ various tools and methods to manage spammers, including domain reputation services, comprehensive reputation systems (like Talos Intelligence), honeypots, feedback loops, data validation techniques, and tracking user consent. Utilizing dedicated IP addresses also allows senders to build their own reputation and improve deliverability.
Key opinions
- Legal Risks: Operating a spammer blacklist can result in legal challenges, particularly defamation and antitrust lawsuits, necessitating accuracy and transparency.
- Accuracy Challenge: Maintaining an accurate and up-to-date spammer list is difficult due to spammers constantly changing their tactics.
- Reputation Services: ESPs use domain reputation services (e.g., Talos Intelligence) to assess senders' trustworthiness, impacting email deliverability.
- Honeypots: Honeypots (fake email addresses) help ESPs identify spammers by detecting unsolicited emails.
- Feedback Loops: Feedback loops with major email providers allow ESPs to receive spam complaints and take action against spammers.
- Consent Tracking: Tracking user consent is essential for legal compliance and maintaining a good sending reputation.
- Data Validation: Data validation techniques help ESPs remove invalid or risky email addresses, improving deliverability.
- Dedicated IPs: Dedicated IP addresses enable senders to build their own reputation, increasing control over deliverability.
Key considerations
- Legal Compliance: Ensure compliance with defamation, antitrust, and data protection laws when operating a spammer list.
- Data Accuracy: Invest in continuous monitoring and updating of spammer lists to maintain accuracy.
- Reputation Monitoring: Utilize reputation services and tools to monitor and improve sending reputation.
- Consent Management: Implement robust consent tracking mechanisms to ensure compliance with email marketing regulations.
- Proactive Measures: Employ proactive measures like honeypots and data validation to identify and mitigate spamming activity.
Marketer view
Email marketer from Talos Intelligence explains that they maintain a comprehensive reputation system that ESPs can use to evaluate senders. This system considers factors like email volume, spam complaints, and malware detection.
3 Mar 2023 - Talos Intelligence
Marketer view
Email marketer from Validity explains that ESPs employ data validation techniques to identify and remove invalid or risky email addresses from their lists. This reduces bounce rates and improves overall deliverability.
10 Dec 2021 - Validity
What the experts say
10 expert opinions
Maintaining a public spammer list involves legal complexities akin to running a credit agency, requiring significant investment, which most ESPs avoid. The risk of lawsuits remains high, even with technical anonymization efforts. Spammers' rapid adaptation makes list updates challenging. Tracking spammers requires sensitive data (bank accounts, addresses), raising privacy concerns. While specific laws targeting spammer lists are absent, defamation, antitrust, and data protection laws apply. Identifying spammers involves tracking patterns, analyzing content, using honeypots, and collaborating. Reputation systems, built on data points like user complaints and spam traps, also help determine sender trustworthiness, and tools like eHawk and ROKSO are used for spammer management.
Key opinions
- High Legal Risk: Maintaining a spammer list carries a high risk of lawsuits related to defamation, privacy, and antitrust.
- Costly Investment: The legal and technical requirements for maintaining a spammer list are expensive, deterring many ESPs.
- Data Privacy Concerns: Tracking spammers requires access to sensitive personal and financial data, raising privacy issues.
- Adaptation Challenges: Spammers can adapt and change their tactics quickly, making it difficult to keep spammer lists up-to-date.
- No Specific Laws: While no laws specifically regulate spammer lists, existing laws like defamation and antitrust apply.
- Identification Techniques: Identifying spammers involves pattern tracking, content analysis, honeypots, and collaboration among ESPs.
- Reputation Systems: Reputation systems relying on user complaints and spam traps help determine sender trustworthiness.
- eHawk & ROKSO: Tools like eHawk and ROKSO are used by ESPs for managing spammers through internal vetting and private discussions.
Key considerations
- Legal Due Diligence: Carefully consider legal frameworks (defamation, antitrust, data protection) before operating a spammer list.
- Privacy Safeguards: Implement strict privacy safeguards when collecting and processing data to identify spammers.
- List Accuracy: Focus on maintaining accurate and up-to-date spammer lists to avoid false accusations and legal challenges.
- Transparency: Be transparent about the criteria and methods used for identifying and listing spammers.
- Collaboration: Encourage collaboration and information sharing among ESPs to improve spammer identification and management.
- Alternative Tools: Consider using available anti-spam tools like eHawk and ROKSO instead of building and maintaining own spammer lists.
- Reputation Monitoring: Implement systems to monitor and evaluate sender reputation as a primary method for spam prevention.
Expert view
Expert from Email Geeks says eHawk does something similar to a spammer list, and Steve Atkins concurs that eHawk is the closest thing out there.
11 Dec 2023 - Email Geeks
Expert view
Expert from Email Geeks shares that even with technical solutions like blinding or hashed searches, the risk of lawsuits remains high when creating a public spammer list.
23 Jul 2023 - Email Geeks
What the documentation says
5 technical articles
ESPs leverage various documented tools and standards to combat spam. Spamhaus maintains real-time blocklists (RBLs) of spam sources. RFC 5782 provides a standard format for abuse reporting to facilitate information sharing. SURBL detects malicious websites within spam messages. Bot management tools block bots used for spam. Google Postmaster Tools allows senders to monitor their email reputation.
Key findings
- RBLs: Spamhaus maintains real-time blocklists (RBLs) that ESPs use to filter spam based on IP addresses and domains.
- Abuse Reporting Standard: RFC 5782 defines a standard format for reporting email abuse, aiding collaboration among ESPs.
- SURBL: SURBL (Spam URI Real-time Blocklist) detects and blocks spam based on malicious URLs.
- Bot Management: Bot management tools are employed to identify and block malicious bots used for spamming activities.
- Reputation Monitoring: Google Postmaster Tools allows senders to monitor their reputation metrics (spam rate, IP reputation).
Key considerations
- RBL Integration: Integrate RBLs into email filtering systems to block known spam sources.
- Abuse Reporting: Adopt and support standard abuse reporting formats like RFC 5782.
- URL Scanning: Use SURBL to detect and block spam based on malicious URLs.
- Bot Detection: Implement bot management tools to identify and block spamming bots.
- Reputation Analysis: Regularly monitor sender reputation metrics using tools like Google Postmaster Tools to improve email deliverability.
Technical article
Documentation from Surbl.org explains that SURBL (Spam URI Real-time Blocklist) detects websites appearing in spam messages. It is used by mail systems to filter spam based on malicious URLs.
17 Mar 2022 - Surbl.org
Technical article
Documentation from Google Postmaster Tools explains that Google provides tools for senders to monitor their reputation. This includes metrics like spam rate and IP reputation, which help senders identify and address issues affecting deliverability.
15 Aug 2022 - Google Postmaster Tools
Besides Spamhaus, what blocklists are important for email marketers to monitor?
How are spammers getting content for their spam emails?
How can ESPs identify and block spammers before they damage IP reputation?
How can you identify spammers?
What are the legal and deliverability implications of including promotional content in transactional emails?
What tools and methods can ESPs use to stress test their email systems and MTA servers?
