Deliverability through the Lens of Spam Filters: Insights from Deliverability Expert, Alison Gootee
Written by
Anusha Nambiar
Anusha Nambiar

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Deliverability through the Lens of Spam Filters: Insights from Deliverability Expert, Alison Gootee

Published : July 10, 2023

Welcome to the seventh blog in our ‘Ask the Expert’ interview series, where we bring you industry experts to talk about outstanding practices in email marketing.

Alison Gootee_Compliance and Deliverability Enablement Principal, Braze

Alison Gootee is a member of Braze’s team of deliverability experts. Based in Vancouver, WA, she is an expert in email deliverability and compliance. Alison’s personal motto is, “too much is never enough except when it comes to sending email.” She is highly experienced in anti-spam legislation and has a deep understanding of the regulatory environment for email like GDPR, CAN-SPAM, and CASL.  Alison helps clients deal with blacklists, spam traps, and ISP issues to improve inboxing and IP reputation.

In this Q&A blog, Alison Gootee talks about the key criteria that spam filters use to assess emails and the use of email deliverability monitoring tools.

1. Tell us about your marketing journey and what inspired you to specialize in email marketing. How did you begin your marketing career, and how did you develop expertise in email marketing along the way?

After a string of unrelated jobs in varying industries that didn’t appeal to me, including waitressing, freight forwarding, and order fulfillment (you could say I’m obsessed with delivering, whether it’s emails, pancakes, or packages), I got hired at MailChimp in 2014. I was already over 30, which is elderly in the tech industry, and I took a pay cut to join the tech support team because I knew it would eventually pay off. Luckily I was right and was rapidly promoted to the Compliance team (to be clear, I was promoted because the job opened up and I applied, not because of my tech support acumen, which was negligible!). On that team, I learned to monitor customers’ sending behaviors for signs of potential Acceptable Use Policy violations and educated wayward senders on best practices.

I moved to Washington State in 2016 and couldn’t take my job with me, so I found one at Emma (a CM Group company) and resumed my Compliance focus. When I saw Braze was hiring, I pestered them until they finally decided that hiring me was the easiest solution. When I started there, I wasn’t sure I’d be able to parlay my Compliance experience into a Deliverability role, but I’ve been at Braze for 4 years now (a personal record!) and have no plans to leave. I hesitate to call myself an expert (and just today referred to this job as the only one I’ve ever had where every day I know less and less), but I’ve worked for some great companies with outstanding people who have helped me get this far! I think that Compliance was the perfect intro to Deliverability, but I have to credit some of my success to my natural inclination towards being nosy, and lifelong insistence on being right.

2. What are the key criteria that spam filters typically use to assess incoming emails? Are there any specific factors that tend to trigger spam filtering more frequently?

Today’s spam filters tend to be super sophisticated, especially compared to their predecessors based primarily on specific keywords. Mailbox providers often clearly spell out their expectations on their website, and mail sent without following those specific rules is likely to be treated as spam. We don’t know every individual factor that mailbox providers are measuring or the intricacies of spam filtering algorithms, but the fundamentals of inbox placement are universal and include: getting permission, managing bounces, removing subscribers who lose interest, authenticating, and generating positive engagement organically. A sender is likely to land in the spam folder if their mail lacks authentication, racks up spam complaints, or languishes unread. Keywords and content are less influential these days because providers have so much more information to go on!

3. What challenges do marketers face to balance between avoiding the spam folder and ensuring that legitimate emails reach their intended recipients?

The major challenge for senders that I work with is balancing their marketing objectives with deliverability guidance. From a revenue standpoint, more emails = more money, but from a reputation perspective, the relationship is much more complicated. Revenue is a marketing goal, but not necessarily a deliverability one. Even for service messages like billing or policy updates, the desired business outcome may not be aligned with email best practices. To ensure that legitimate emails reach their intended recipients, brands still need to follow best practices that go beyond legal requirements, which is often a tough sell, especially for those that don’t utilize other channels like push or SMS and feel that email is their only option.

4. How does the reputation of an email domain and IP address impact email deliverability and spam filtering?

Domain and IP reputation are huge! Filters definitely take both into consideration when determining whether and where to deliver mail, though only they can say for sure what the weighted value is for each, and it certainly varies among providers. Domain reputation used to be considered less important than IP reputation, but these days we’re seeing that algorithms are better able to distinguish between senders on the same IP and make filtering decisions based at least partially on domain reputation. This has made it easier for senders in a shared IP pool to differentiate themselves from their potentially problematic neighbors, but it’s far from full immunity.

Mailbox providers and blocklisting organizations can implicate neighboring senders as a deterrent so that ESPs are more likely to take corrective action toward the problematic sender(s). Exceptionally bad behavior from one or multiple senders can still impact other senders on the same or adjacent IPs, especially if the mailbox provider doesn’t see evidence that the behavior is being curtailed. Senders should ensure their ESP has a strong Acceptable Use Policy or Anti-Spam Policy and a Compliance team to enforce it because an ESP is only as strong as its weakest sender.

5. What is the significance of using email deliverability monitoring tools to assess the likelihood of emails being flagged as spam? How can these tools aid in understanding and improving email deliverability rates?

This may be an unpopular opinion, but I think deliverability monitoring tools are superfluous in many cases, especially for spam testing. More information is always better unless the information is needlessly fear-mongering or unactionable. The drawback of spam tests that I’ve seen is that they generally don’t mimic your actual sending or subscriber behavior, so they can’t provide an accurate assessment and may even flag aspects that have no noticeable impact on your results. A better option would be to create your own testing accounts with various providers so that you can view the message and where it landed. There are some downsides to this approach, though. Since filters are so highly attuned to individual engagement, mail will be delivered based on your sending domain/IP reputation and your recipient engagement history, meaning that where the mail lands for you may not be the same as where it ends up for someone else.

Deliverability monitoring tools can help you discover trends, blocklistings and (some) spam trap hits, but a lot of the information should be considered additional data points as opposed to objective truths. In other words, if your monitoring tool says everything is great, but you’re seeing lower-than-expected engagement, something is probably going awry. First-party data should always be your first stop, but monitoring tools can help surface additional signs of success or failure.

6. What measures can be taken to ensure that a content filter does not mistakenly classify legitimate emails as spam, especially when structuring email content according to best practices?

Content filtering is far from my forte, but my understanding is that, like much of deliverability, honesty is the best policy. Attempting to evade filters won’t work for very long, if at all, so I don’t recommend any specific behaviors to try to avoid them. If you’re sending wanted and expected mail that adds value to your subscribers’ lives, then the problem will work itself out. If your mail is being blocked by a content filter, you may be able to reach out to the domain administrator or mailbox provider to request a review, but most often, the best thing to do is to be consistent so that, eventually, your mail is recognized as legitimate.*

*As always, legitimacy is in the eye of the receiver, not the sender, so ensure you have permission before sending an email every time.

7. What role does opt-in permission play in avoiding spam filters? How important is it for subscribers to be familiar with the brand?

Permission is the number one, all-time, most valuable player when it comes to reaching the inbox. Without permission, you’re a spammer, and spam is gross. Think of a brand you love. Now imagine they just email you out of the blue, and you definitely never gave them your address. It would be weird, right? Either they somehow got your address without your permission (A privacy violation way beyond the likes of Instagram ads for items you mentioned out loud once!), or their brand is being impersonated for nefarious purposes. Both are bad!!

Not only does mail perform better when senders have permission, but it helps keep the internet safe for vulnerable people. Hear me out! If we all just accept that brands send mail without permission, then how is my grandma supposed to know which emails are legitimate and which ones are dangerous!? When standards are ignored, it’s harder to tell an actual scam from an accidental poor practice. Without permission, everyone would just click every email that asks for an updated payment method, and we’d all be broke. I don’t want to live in that world! So, for the love of my grandma and to avoid spam filters, not only should recipients recognize a brand, but they should recall signing up and recognize the domain and branding so that they can instantly tell if something is sketchy.

8. What proactive measures can email service providers adopt to enhance and optimize their spam filtering capabilities, ensuring more accurate detection and prevention of spam emails?

With apologies to my customers and colleagues, I actually wish some mailbox providers were more aggressive with their spam filtering and blocking. I am a staunch supporter of best practices, including double opt-in and aggressive list management, but most senders are reluctant to implement them because there’s little incentive, especially if they have historically generated positive results. If senders were bulked earlier or more aggressively, DOI and sunset policies would become the more appealing alternatives to the constant loss of access to the email channel.

As an email user, I would love if mailbox providers offered more feedback options aside from the spam button, like a thumbs-up or down to indicate “Yeah, I like this,” or “I purchased from this brand, so I feel bad reporting this as spam, but I didn’t sign up,” or an “I like these emails but don’t need them every day” button. They could even attempt to collect direct feedback, like asking if users recognize the sender and expect the mail.  As an email geek, I would love to see that feedback so that I could help senders take action on it and build The Perfect Email Program. In general, I actually think the current system works pretty well, but I would never say no to more information!

9. What are the key indicators to look for in bounce and SMTP replies that may signal a potential issue with spam filters impacting deliverability?

First of all, read your bounce logs regularly! They are SO juicy and often explicitly describe the reason a mail was rejected, and may even provide a link to some help docs. Bounces of all kinds can impact your sending reputation because the data quality is another signal available to mailbox providers, so keep an eye on full mailboxes, non-existent addresses, and invalid recipients, just to name a few. If the logs indicate that mail is being rejected due to being classified as spam (If that’s what is happening, then they will. If your bounces don’t mention spam, then something else is wrong.), the first step is to verify whether you obtained permission prior to sending. This is actually the first step for every deliverability problem, to be honest!

Permission doesn’t mean a purchased list of opt-in addresses, a list a partner shared with you, or even all your registered app users. Permission means that the person who owns and manages the email address specifically and directly asked to be on your mailing list and ideally confirmed that request by clicking on a confirmation email (or provided a confirmation code from an email).

People who want your mail are inclined to give you an address that can accept it, so rejection can signal that something is amiss with the subscription process or that it’s time to sunset inactive addresses. If the address voluntarily opted in and confirmed signup recently, look at other addresses on the same domain. If the issue is limited to a single address, then that specific address may have reported your mail as spam in the past and is now bouncing. If it’s a domain-wide problem, then your mail likely generated too many spam complaints, culminating in being blocked, or the domain might reject all marketing mail as a matter of course. There are infinite bounce reasons, so if you don’t know what one means, Google it! If Google doesn’t know, then ask the Email Geeks Slack group. And if they don’t know? You should probably just stop emailing that address!

10. How do spam filters evolve, and what should senders be aware of regarding changes in filtering algorithms?

Spam filters are fairly opaque to senders by design, but it seems that they evolve over time based on sender behavior and several subscriber engagement factors, many (or most) of which senders don’t have access to. This is why deliverability folks constantly bang the ‘best practices’ drum; engagement can’t be faked sustainably, and long-term success relies on building a strong foundation. Senders should focus less on filtering algorithm changes and more on ensuring that the fundamentals of deliverability are integrated into their lifecycle marketing strategy. If you’re collecting explicit and optional permission to send emails, following the technical specs, and delivering value to subscribers, the filtering algorithm could change a million times and still barely impact your bottom line.

Understanding the intricate relationship between email spam, deliverability, and sender reputation is crucial for effective email marketing campaigns. By adopting best practices such as sending relevant and engaging content, utilizing authentication protocols, and monitoring feedback loops, businesses can improve their email deliverability and ensure that messages reach the intended recipients.

Netcore is constantly innovating to enhance sender reputation with mailbox service providers and increase email deliverability. We are monitoring a broad range of metrics and huge volumes of performance data to decipher every new spam filtering algorithm. Connect with us to understand how you can benefit from our expertise and experience. We send over 20 billion emails a month on behalf of 6500+ businesses across 40 countries.

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Written By: Anusha Nambiar
Anusha Nambiar
Executive Product Marketer