You're paying your ESP to destroy your sender reputation and lose your best customers. And I can prove it.
— Chuck Mullaney, 25-year email deliverability veteran
97% of our clients had this problem. Almost none knew.
Want to understand the problem before you diagnose it? Read the research behind this tool.
The Phantom Engaged ProblemHere's What Your ESP Won't Show You.
The Visible
What you can measure
The Invisible
The blind spot
1 blind spot that creates 2 problems.
You're treating bots as fans. And some of your biggest fans as dead weight.
Don't worry. We have answers.
Your Re-Engagement Snapshot
You're sending to subscribers. You've identified roughly of them, about % of your audience, as showing no meaningful engagement signals. That leaves that you're currently treating as engaged.
That second number deserves scrutiny. It's almost certainly too high, and the framework below will show you exactly why.
Since you said you haven't run a formal re-engagement campaign, those subscribers may have been accumulating silently. And without this new structured re-engagement process in place, you have no mechanism for determining how many of the remaining are actually engaged versus simply appearing that way. Every send that reaches an unresponsive inbox without a plan behind it is a data point ISPs use against you (especially Google, and we all know how important Gmail inboxing is).
You've recently attempted re-engagement, which means you already know this is a problem. The question is whether the approach accounted for the subscribers hiding between your “engaged” and “unengaged” segments. The ones your ESP shows as active but whose engagement can't actually be verified.
You ran a re-engagement effort within the last 90 days. If it didn't move the needle the way you expected, the framework below will show you a likely reason: most re-engagement campaigns treat the list as two groups, engaged and unengaged, when there are actually three. The invisible middle group is where campaigns quietly fail.
Your last re-engagement attempt was long enough ago that the landscape has changed underneath you. Privacy protections like Apple's Mail Privacy Protection have fundamentally altered what “engagement” even means. Subscribers your ESP reported as “engaged” the last time you ran this exercise may no longer be provably engaged today.
You've indicated that your deliverability is currently healthy, which is exactly why now is the time to address this. Sorting out your identified unengaged subscribers and determining the true engagement status of the remaining while your reputation is strong is dramatically easier than doing it after ISPs start throttling you.
You're already seeing inconsistencies in your deliverability. With % of your list identified as unengaged, and an unknown additional portion whose “engagement” may be phantom signals from privacy proxies, there's a direct line between that uncertainty and the inbox placement issues you're noticing.
Your deliverability has recently declined, and the problem may be bigger than the subscribers you've identified. ISPs interpret continued sending to unresponsive addresses as a lack of list hygiene, and if a portion of your remaining subscribers are phantom engaged rather than actually active, you're sending to more unresponsive addresses than you realize. That impacts inbox placement for everyone on your list, including the subscribers you can prove are reading.
You're not sure about your deliverability health, and that uncertainty is itself a risk factor. With % of your list identified as unengaged, and no way to know how many of the remaining are actually active versus phantom engaged, there's a meaningful chance your inbox placement is already being affected and you don't have visibility into it.
The framework below breaks your list into three categories, not the two you're used to, and gives you the exact protocol for handling each one without damaging your sender reputation in the process. It starts with a concept most email marketers have never encountered.
Engagement In The Modern Era
Engagement classification has fundamentally changed. Open rates are no longer a reliable proxy for human interest due to privacy protections like Apple's MPP. In this environment, aggressive re-engagement can damage domain reputation. We adhere to a conservative, signal-first approach to protect list health while attempting to recover value. This goal is long term stability, not short term volume.
Why this matters for your list: The instinct is to treat your list as 2 groups, engaged and unengaged. Both your ESP and your gut reinforce that view. But it's wrong.
You entered total and unengaged, which means you're treating the remaining as engaged. But a significant portion of that group is 100% Phantom Engaged: subscribers whose “opens” are generated by privacy proxies, not human behavior.
The actual number of confirmed engaged subscribers on your list is likely lower than , and you won't know by how much until you apply the observation window below.
This framework splits your list into 3 buckets, not 2. The middle bucket, Phantom Engaged, is the one most email marketers have never considered. It's also the one that determines whether your re-engagement effort helps or hurts. Here, let me show you what I mean:
The 3 Subscriber Buckets
Bucket A: Confirmed Engaged
Subscribers showing verified human intent such as clicks, replies, or purchases. Opens are optional, but Bucket A requires undeniable human interaction.
Bucket B: Phantom Engaged
Subscribers showing opens without other human intent. These signals may be human or automated. This bucket represents uncertainty, not behavior.
Bucket C: Unengaged
Subscribers showing no engagement signals whatsoever, not even opens, within a defined observation window. These subscribers require controlled, finite re-engagement.
Now that you can see all three categories, here's the good news: each one has a clear protocol. Bucket A takes care of itself. Bucket B and C are where this framework gives you the clarity you've never had before. Let's walk through exactly what to do.
This framework exists inside a done-for-you sprint. Your list gets classified for real, your best customers stop getting buried, and the subscribers you've been afraid to touch get handled safely. One person built this framework, and one person runs every sprint.
arrow_forward See How The Sprint WorksThis is the bucket that matters most for your situation. You're tracking opens but not clicks, replies, or purchases. That means right now, you have no reliable way to distinguish between a subscriber who actually opened your email and one whose device auto-loaded tracking pixels through Apple's Mail Privacy Protection or a corporate security filter.
Some portion of your “unengaged” subscribers may actually be opening. They just don't have a click or reply to prove it. And some portion of the you're treating as “engaged” may not be engaged at all. Their “opens” are machine-generated.
Without stronger signals, your -day observation window is the only mechanism for beginning to sort this out. It won't give you certainty, but it gives you a defensible classification.
But that doesn't eliminate Bucket B. Among the subscribers you're treating as engaged, there are still those who show opens but have never produced a verifiable signal. Those subscribers are phantom engaged until proven otherwise. The -day observation window below is how you make that determination.
Bucket A: Confirmed Engaged — Your Foundation
These are subscribers who have produced verifiable human signals: . They are your foundation. Continue sending to them normally. They protect your sender reputation and generate the engagement metrics that ISPs use to evaluate your domain.
No action required here beyond maintaining the quality of your content and monitoring for engagement decay over time.
Bucket B: Handling Phantom Engagement
Phantom Engaged subscribers (opens onlyopens without provable intent) require a specific observation window to determine safety. Classification relies on sending frequency.
Your Observation Window:
-- Days
Reference:
Daily sending: classify after 45 days.
Weekly sending: classify after 60 days.
Monthly/Sporadic sending: classify after 90 days.
Action: This is an active diagnostic protocol, not passive observation. During the ---day window:
- Reduce sending frequency for this group specifically. Do not continue your normal cadence.
- Change the content strategy. Every message sent to Bucket B during the observation window must require a human action to register engagement — a click, a reply, or a purchase. Opens alone cannot distinguish humans from bots, which is the entire reason these subscribers are in Bucket B.
- Observe for the full classification window. You are deliberately creating conditions where a real human would reveal themselves and a bot or proxy engagement would not.
- If they produce a verifiable human signal (click, reply, purchase) during the window, move them to Bucket A (Confirmed Engaged).
- If they produce no human signal after the window expires, move them to Bucket C (Unengaged).
The frequency reduction prevents further deliverability damage while the diagnostic runs. The content change — requiring clicks and replies, not just opens — is the core mechanism that separates real subscribers from phantom engagement.
This classification process is one of the three deliverables in the done-for-you sprint, built directly inside your ESP using your real subscriber data.
The observation window gives you a way to classify Phantom Engaged subscribers over time. But it doesn't address the subscribers who are clearly unengaged, the ones with no signals at all. That's Bucket C, and it's where the stakes are highest. The wrong approach here doesn't just fail to recover subscribers. It actively damages your ability to reach the ones who are still paying attention.
Everything you just read about handling Phantom Engaged subscribers is what the sprint does. 30 to 60 days of controlled re-engagement, monitored daily, using software built specifically for this. You don't run it. I do.
arrow_forward See How The Sprint WorksHere's where discipline protects your entire operation. With subscribers in your identified unengaged pool, the temptation is to re-engage them all at once and “get it over with.” But if you send to all simultaneously, that's a % spike in volume hitting addresses that haven't responded to you in months. ISPs don't just penalize that batch. They throttle delivery to your entire list, including your confirmed engaged subscribers, the ones you can actually prove are reading.
And remember: if your Phantom Engaged bucket is larger than you think, which, based on your inputs, it likely is, then you're already sending to more unresponsive addresses than your ESP is showing you. A mass re-engagement blast on top of that would compound the problem.
The controlled approach below keeps you under the radar.
Bucket C: Controlled Re-Engagement
We do not blast unengaged subscribers. We re-engage in controlled waves alongside normal campaigns. Note: This volume threshold is reduced from older practices to account for modern uncertainty.
This is exactly what the done-for-you sprint is built to manage. Every re-engagement send is individually monitored against live deliverability signals, with daily adjustments based on how ISPs are responding.
Maximum Daily Re-Engagement Volume:
-- Subscribers / Day
This cap represents 5% of the you've
identified as unengaged.
Start with the warmest unengaged subscribers first.
So you know the daily volume. You know to start with the warmest subscribers first. But there's one more rule that most re-engagement campaigns ignore, and ignoring it is how well-intentioned cleanup efforts turn into reputation-damaging loops.
The Two-Send Limit
Re-engagement is finite. It does not repeat logic loops.
- Each unengaged subscriber receives exactly two re-engagement specific emails.
- Exit Rule A (Success): Any click or reply immediately moves them to Bucket A (Confirmed Engaged).
- Exit Rule B (Failure): If no action is taken after email #2, the subscriber is permanently suppressed.
The sprint runs this entire Bucket C process for you, including volume pacing, warmest-first sequencing, exit rule enforcement, and permanent suppression of non-responders. It uses proprietary software that isn't publicly available to monitor every send in real time.
⚠️ CAUTION: Stabilization Recommended First
You indicated --.
Prioritize stabilization before expansion.
- Reduce re-engagement velocity or pause entirely.
- Focus sending ONLY to Bucket A (Confirmed Engaged) for 2-4 weeks.
- Wait for deliverability metrics to stabilize before attempting further re-engagement.
Right now, unengaged subscribers are hurting your sender reputation every time you hit send. Your biggest fans are getting buried because your ESP can't tell them apart from bots. And the subscribers you've been afraid to mail or delete are sitting there costing you money every month while you wait for a safe way to deal with them. The sprint resolves all three. Your list gets classified with real data. Your recoverable subscribers get re-engaged safely. And you stop guessing.
arrow_forward See How The Sprint WorksReEngage Pro is the software behind this sprint. It's the same system used to classify subscribers and run controlled re-engagement on client lists. It's not publicly available yet, but it will be. If you want to run this process on your own list when it launches, the waitlist is how you get early access.
Join the ReEngage Pro Waitlist