How does Invaluement compile its blocklists?

Invaluement compiles its blocklists by actively monitoring spam and malicious email patterns. It focuses on identifying elusive spam that bypasses traditional filters, using sophisticated analysis to detect abusive IP addresses and URIs (domains/URLs) found within spam messages. Their system aggregates data from various sources to pinpoint senders and content associated with unwanted bulk email.

Which domains or ISPs use Invaluement for email filtering?

While specific, comprehensive lists of domains that use Invaluement are not publicly available due to proprietary filtering configurations, historically, some large entities like Cox and Bigpond.com have incorporated them. Mailbox providers and corporate filtering systems that prioritize catching evasive spam are more likely to utilize Invaluement as an 'add-on' to their primary defenses.

What is the impact of being listed on an Invaluement blocklist?

The impact of being listed on Invaluement can vary. For email systems that use their lists, emails from your affected IPs or domains may be rejected, quarantined, or sent to the spam folder, leading to reduced deliverability. While its overall reach might not be as wide as major global blocklists, it still contributes to your sender reputation and can cause significant issues for a segment of your audience.

How do I get delisted from an Invaluement blocklist?

To get delisted from Invaluement, first identify and resolve the root cause of the listing (e.g., spam complaints, compromised accounts, abusive URLs). Then, visit the Invaluement website and follow their specific delisting procedures. They are generally known for prompt delisting once the issue has been remediated.

Is Invaluement as influential as other major blocklists like Spamhaus?

Invaluement focuses on detecting evasive spam and is a valuable complement to other filtering systems. However, it is generally not considered as universally impactful as some of the largest global blocklists, such as Spamhaus, which are used by a much broader range of major mailbox providers and ISPs worldwide. Each blocklist has its specific niche and level of influence.

Which domains use Invaluement lists for email filtering and what is their impact? - Sender reputation - Email deliverability - Knowledge base

When managing email deliverability, understanding the various blocklists and their impact is crucial. Among them, Invaluement stands out as a set of DNS-based blocklists (DNSBLs) specifically designed to identify and filter out elusive types of spam, making it a component in various email filtering systems.

A common question I hear is which major internet service providers (ISPs) or email service providers (ESPs) actively utilize Invaluement lists for their email filtering. Historically, some notable domains, like Cox and Bigpond.com, have been known to incorporate Invaluement into their spam prevention strategies. However, the exact current widespread adoption by the largest global providers is often less clear, as many keep their specific filtering configurations proprietary.

Despite this, even if Invaluement isn't universally adopted by every giant mailbox provider, being listed on its blocklists can still have a tangible impact on your email deliverability. For organizations and domains that do rely on Invaluement, a listing can lead to emails being rejected, quarantined, or routed directly to the spam folder, underscoring the importance of understanding and mitigating potential issues.

Understanding invaluement's lists and their purpose

Invaluement operates three primary DNS-based blocklists, each targeting different aspects of spam activity. Understanding these distinctions is key to comprehending their filtering logic and potential impact. The lists are designed to complement standard spam filters by catching more sophisticated or evasive spam patterns.

The ivmURI list focuses on Universal Resource Identifiers (URIs). This means it targets domains and URLs that appear in the body of spam emails, rather than just the sending IP address or domain. This is particularly effective against spam campaigns that use legitimate sending infrastructure but include malicious or spammy links. The ivmSIP and ivmSIP/24 lists, on the other hand, target IP addresses associated with spamming behavior.

Invaluement.com explains that these lists pinpoint the most elusive spams, where senders manage to escape traditional filtering.

These lists are generally intended to be used as an add-on to existing email and spam filtering systems, rather than serving as the sole filtering mechanism. This layered approach to filtering helps catch a broader range of unsolicited emails. To learn more about how different blocklists operate, you can consult a simple guide to how email blacklists actually work.

List Name	Focus
ivmURI	Domains and URLs found within spam messages.
ivmSIP	IP addresses sending spam; general IP-based spam activity.
ivmSIP/24	IP address ranges (specifically /24 subnets) with significant spam activity.

Impact of Invaluement listings on email deliverability

The direct consequence of being listed on any Invaluement blocklist is that emails originating from your affected IP address or containing your listed domain/URL are likely to be rejected or diverted to the spam folder by email systems that subscribe to these lists. This can lead to a noticeable drop in your email deliverability rates for specific recipients.

While Invaluement may not have the same sweeping impact as a major blocklist like Spamhaus, its influence should not be underestimated. According to some sources, Invaluement has been considered one of the more influential blocklists. For example, Act-On highlights it as a strong and widely impactful blocklist, particularly for corporate email filters such as

Mimecast. This means that for a subset of your audience, a listing could still lead to significant deliverability issues. We have an article that delves deeper into Invaluement's current relevance for email deliverability.

It's important to remember that sender reputation is a cumulative factor. While one blocklist listing alone might not cripple your entire email program, it contributes to an overall negative perception of your sending practices. This can make other filters more likely to flag your emails, even if those filters don't directly use Invaluement. This complex interplay highlights why understanding your email domain reputation broadly is so important.

The domino effect of listings

Even if a blocklist (or blacklist) like Invaluement is considered less impactful than a giant like Spamhaus, a listing still signals a negative sender reputation. This can cause other filtering systems to view your emails with increased suspicion, potentially leading to widespread deliverability issues across various mailbox providers. Each listing, no matter how small, contributes to your overall sender score.

Identifying domains that use Invaluement

Pinpointing which specific domains actively use Invaluement's lists for filtering can be challenging because many organizations do not publicly disclose their exact spam filtering configurations. However, the most reliable way to identify if Invaluement is affecting your emails is by closely monitoring your email logs and bounce messages. Specific bounce codes or diagnostic messages often indicate the blocklist responsible for the rejection.

Invaluement itself provides lookup tools on its website where you can manually check the status of specific IP addresses or URLs against their lists. This can be a proactive step to determine if your sending infrastructure or linked content is currently listed. Additionally, understanding the different types of email blocklists can help you interpret lookup results.

While you might not get a definitive list of all domains using Invaluement, focusing on maintaining a strong sender reputation across the board is paramount. Many large mail providers use a combination of various blocklists, internal filters, and proprietary algorithms to determine inbox placement. For a broader overview of important blocklists, consider reviewing other blocklists important for email marketers.

Example DNSBL Query (General)bash

dig +short A <IP_ADDRESS>.sbl.spamhaus.org
dig +short A <DOMAIN>.multi.uribl.com

Strategies for avoiding and resolving Invaluement listings

The best way to avoid a listing on Invaluement, or any other blocklist (also known as a blacklist), is to adhere to best practices for email sending. This includes maintaining a clean and engaged email list, avoiding sending unsolicited bulk email (spam), and ensuring your email authentication protocols like SPF, DKIM, and DMARC are correctly configured.

If you find that your domain or IP is listed on Invaluement, prompt action is essential. Invaluement is known for its relatively quick delisting process once the issue causing the listing has been resolved. You will typically need to visit the Invaluement website and follow their specific procedures for removal, which usually involve providing details about the remedial actions taken. For a general guide on getting removed from blacklists, Mailgun provides helpful steps.

Proactive monitoring of your sender reputation and consistent adherence to email best practices are your best defenses. Regularly using a blocklist checker and responding swiftly to any deliverability issues can help mitigate the impact of listings and maintain your email sending reputation. Understanding how to determine the severity and mitigate different blocklists is a crucial skill for email marketers.

It's also worth noting the critical role email authentication plays in avoiding blacklists. Implementing and properly configuring SPF, DKIM, and DMARC records helps recipient servers verify that your emails are legitimate and prevents spoofing, which is a common reason for blocklist inclusions.

Proactive measures

List hygiene: Regularly clean your email list by removing inactive subscribers and hard bounces. This minimizes spam trap hits and complaints.
Authentication: Ensure your SPF, DKIM, and DMARC records are correctly set up. These are foundational for proving email legitimacy.
Content quality: Avoid spammy keywords, excessive links, or misleading subject lines. Focus on valuable, relevant content.
Monitoring: Consistently monitor your sender reputation and check various blocklists to catch issues early.

Reactive measures

Identify cause: Determine the root cause of the listing (e.g., spam complaints, compromised account, unusual sending volume).
Stop abusive behavior: Immediately stop any sending practices that led to the blocklisting. This is crucial for successful delisting.
Delisting request: Visit the specific blocklist's website (e.g., Invaluement's) and follow their delisting instructions. Be prepared to explain your corrective actions.
Monitor and recover: After delisting, continue to monitor your deliverability closely and rebuild your sender reputation over time.

Views from the trenches

Invaluement plays a role in the broader ecosystem of email security, and the community has shared experiences regarding its impact and operation. From anecdotal evidence to insights from experienced professionals, these views offer practical perspectives on dealing with Invaluement listings and maintaining good email deliverability.

Best practices

Proactively monitor your IP and domain against Invaluement lists using their lookup tools.

Ensure rigorous email list hygiene to prevent spam trap hits, which are often picked up by URI lists.

Implement robust email authentication (SPF, DKIM, DMARC) to validate your sending legitimacy.

Respond swiftly to any bounce messages indicating an Invaluement block, then follow their delisting process.

Educate your team on email best practices to prevent accidental spam triggers.

Common pitfalls

Ignoring bounce messages that cite Invaluement, prolonging deliverability issues.

Failing to address the root cause of a listing, leading to re-listings.

Underestimating the cumulative impact of even 'lesser' blocklists on overall sender reputation.

Using URL shorteners without careful consideration, as they can lead to URI blocklist issues.

Neglecting to monitor shared IP spaces if you are using an ESP, as others' actions can affect you.

Expert tips

Maintain transparency with your ESP about your sending practices to ensure compliance.

Understand that some ISPs use Invaluement as a supplementary filter, so its impact can be localized.

Focus on engagement metrics; low engagement can signal spam-like behavior to blocklists.

Keep an eye on trends in spam techniques, as Invaluement specifically targets evasive spam.

Utilize DMARC reports to identify sources of unauthorized sending that could lead to listings.

Expert view

An expert from Email Geeks says that Cox used to utilize Invaluement, but data suggests its overall usage for blocking has become very light, accounting for a small percentage of total blocks observed in 2017.

2020-04-10 - Email Geeks

Marketer view

A marketer from Email Geeks noted that Bigpond.com actively uses Invaluement for its email filtering processes.

2020-04-10 - Email Geeks

Maintaining deliverability in a complex landscape

While Invaluement lists might not be as universally adopted by the largest mailbox providers as some other major blocklists (or blacklists), they still hold relevance within the broader email filtering landscape. Domains and email systems that utilize Invaluement can significantly impact your deliverability if your IPs or URLs are listed. Proactive monitoring, adherence to best practices, and swift action for delisting are essential to minimize any negative effects and maintain a healthy sender reputation. Staying informed about various blocklists and their unique focuses is a critical part of a robust email deliverability strategy.